JP2010255861A - Method of controlling reheating of exhaust gas in cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of controlling the reheating of an exhaust gas in a cogeneration system capable of improving a boiler protecting function by promptly breaking away a boiler overload caused by an operation generating excess evaporation and the overheating of a boiler heat transfer pipe. <P>SOLUTION: A group of a "predicted reheating amount" generating boiler-specific set pressure is operated within a range that an exhaust gas from a motor does not exceed a "boiler operation allowable maximum temperature", and "achievable evaporation" at this time is also operated. A maximum value of the "predicted reheating amount" is applied until an "overload lower limit value" caused by the overload is detected, and a minimum value of the "predicted reheating amount" is applied as a reheating amount when the "overload upper limit value" is detected. An intermediate corresponding value between the maximum value and the minimum value is applied when exceeding the "overload lower limit value" of a factor in reheating, and adjusted by an opening of a fuel flow rate control valve of a reheating burner. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an exhaust gas tracking control method in a cogeneration system, and is applied to a cogeneration system in which a power generation facility and an exhaust heat boiler are combined and thermoelectrically supplied. More specifically, when pursuing exhaust gas supplied to a waste heat boiler from a gas turbine of a power generation device, when the exhaust heat boiler is overloaded, it can be quickly removed from the boiler to protect the boiler. At the same time, it is possible to secure an evaporation amount that does not rapidly modulate the operation of the facility that receives and consumes steam from the boiler (hereinafter referred to as “steam demand side”). Furthermore, when there is an excessive amount of steam demand exceeding the planned time from the steam demand side, heat is generated so that the amount of evaporation to the full capacity of the steam generation of the boiler (maximum allowable evaporation amount inherent in the boiler) can be obtained. The present invention relates to a boiler supply exhaust gas replenishment control method that enables additional supply of energy so that, even in this case, if an overload occurs, a quick escape from the overload can be achieved.

  While generating power using a prime mover such as a gas turbine, gas engine, diesel engine, etc., and operating a waste heat boiler using the exhaust gas, energy that satisfies both power demand and steam demand simultaneously while achieving energy-saving operation Can supply. Such a cogeneration system (combined heat and power) is known from Japanese Patent Laid-Open No. 5-86900 and is very useful in various plant facilities such as a chemical plant, and its introduction has become increasingly popular these days. Yes.

  Since this type of cogeneration system has been mainly based on electricity demand in the past, the amount of steam generated in the exhaust heat boiler is generated by heat energy that uses exhaust gas from the power generator and tracks it to some extent. It is kept to the extent possible. In other words, in a plant or ancillary equipment where the amount of steam consumption is not particularly problematic or the demand amount itself is not large, the amount of steam generated will be secondary to follow-up, and the operation of generating excess capacity evaporation and boiler heat transfer tubes In consideration of overheating (hereinafter referred to as “boiler overload operation”), the amount of remedy when the exhaust gas temperature at the boiler inlet reaches the maximum allowable operating temperature, for example, 850 ° C. is defined as the maximum combustion amount of the remedy burner, and the maximum combustion Until the amount is reached, the steam drum pressure is maintained at a set pressure (ordinary pressure, for example, 1.27 MPa) by PID control in the same manner as is normally employed in boilers.

  By the way, a cogeneration system equipped with a memorial burner has a concept for a long time. For example, as disclosed in Japanese Patent Application Laid-Open No. 8-159411, etc., various types of system configurations have been devised so far and these are publicly known. FIG. 31 shows an example. When such a cogeneration system is introduced, it is considered that the exhaust heat boiler 2 suitable for the amount of exhaust gas that can be supplied from the generator 8 is combined. However, the required evaporation amount on the steam demand side 24 is not necessarily the exhaust heat boiler. It is not always satisfied. Therefore, as the exhaust heat boiler, one having a sufficient steam generation capacity to satisfy the required evaporation amount on the steam demand side is employed.

  This means that even if the steam demand side requires more than the evaporation amount at the time of planning the cogeneration system, the exhaust heat boiler can respond to it. In this case, the amount of evaporation can be increased by increasing the amount of chasing, but the amount of chasing is not limited. This is because the upper limit of the evaporation amount is set for the reason that the boiler water circulation is not disturbed in the boiler, and restrictions are imposed on the exhaust gas temperature introduced in consideration of the heat resistance of the water tube group. .

  Unless the allowable maximum evaporation amount inherent in the boiler is required from the steam demand side, the pressure of the steam drum 11 and the like can be maintained at the above-described normal pressure and the boiler inlet exhaust gas temperature can be maintained lower than the maximum allowable operation temperature. There is no hindrance to the operation of the boiler due to the chasing, and it can always be operated safely. In other words, when the amount of remedy is suppressed so that the exhaust gas temperature at the boiler inlet does not exceed the allowable value, for example, 850 ° C., the operation is unavoidable even if the allowable maximum evaporation amount cannot be generated. become.

  In this case, it is necessary to monitor the exhaust gas temperature at the boiler inlet with the sensor 22 and to check the amount of evaporation each time with the flow sensor 25, but as a measure once it is overloaded, it is calculated by PID control. For example, the current exhaust amount is reduced by 10%, the boiler inlet exhaust gas temperature and the evaporation amount are checked, and if any overload still remains, it is further reduced by 10%. It becomes necessary to try to escape from overload, such as by controlling the amount.

  However, in this case, the measurement accuracy of the sensor for detecting the boiler inlet exhaust gas temperature and the evaporation amount must be highly reliable. Even if it is a sensor that can detect accurately, a decrease in temperature and evaporation reflected in a gradual reduction in the amount of remedy involves a time lag that is difficult to ignore, and it takes time to escape from overload. In addition, it is difficult to say that the sensor detection value of the boiler inlet exhaust gas temperature is always accurate under the influence of furnace wall radiation and the like. It is suspicious that the flow meter that detects the amount of evaporation is always accurately detected because it may be subject to changes in the operating environment. So, if you drop it down to the minimum amount of boiler operation, that is, the minimum combustion amount to increase the amount of reduction of the memorial amount, the escape will be faster, but the rapid decrease of the memorial amount will cause a large fluctuation in the evaporation amount, Due to the sudden shortage of steam, the operation on the steam demand side can be disrupted.

  By the way, when the consumption on the steam demand side becomes intense, the state in which the vapor pressure (drum pressure) suddenly decreases or falls below the normal pressure temporarily continues. Since the PID control attempts to return the vapor pressure to the normal pressure, the amount of renewal will be increased. This increase will cause the gas supplied to the exhaust heat boiler to exceed the maximum allowable operating temperature of 850 ° C, or the amount of evaporation Cause over-extension. In consideration of such a situation, the exhaust heat boiler should be structured to withstand overload operation, or a boiler with a capacity that is 2 ranks or 3 ranks higher than the demand on the steam demand side must be selected to enter overload operation. I have to make sure that nothing happens. Regardless of the rank of one rank or higher, the exhaust heat boiler of the higher rank is unavoidably excessive in capacity, and forces an unnecessary increase in equipment cost.

JP-A-5-86900 JP-A-8-159411

  The present invention has been made in view of the above-mentioned problems, and its purpose is to allow the maximum allowable evaporation amount inherent in the boiler when there is a request for an excessive evaporation amount exceeding the plan at the time of cogeneration system planning from the steam demand side or In this case, even if the boiler is overloaded, such as generation of excess capacity evaporation or overheating of the boiler heat transfer tube, the boiler protection function is enabled by enabling quick removal from it. At the same time, the amount of evaporation is not excessively reduced or fluctuated so that the operation on the steam demand side is not rapidly modulated. In addition, even if the operation is only to meet the evaporation requirement within the planned range from the steam demand side, if it falls into an overload operation, it will promptly escape from it and unintentionally decrease or fluctuate the evaporation amount It is to provide an exhaust gas renewal control method for a cogeneration system that can suppress the above.

The present invention relates to an exhaust heat boiler configured to determine the amount of exhaust gas to be added by calculation based on PID control based on the detected steam pressure in order to keep the steam pressure of the boiler at a set pressure (ordinary pressure), and its The present invention is applied to an exhaust gas tracking control method in a cogeneration system including a prime mover that generates exhaust gas to be supplied to an exhaust heat boiler when the generator is driven. The feature is (1) Exhaust gas 4 generated according to several typical prime mover intake air temperatures during operation of the prime mover 7 (see FIG. 1) and several typical loads at that time. However, within a range that does not exceed the pre-determined maximum allowable boiler operation temperature at the inlet of the exhaust heat boiler, a group of "predictive tracking amounts" that generate the set pressure unique to the exhaust heat boiler is calculated. And calculating the “achievable evaporation” at this time,
(2) In case the detected value of the boiler overload factor corresponds to overload operation, the “maximum value in the expected amount of tracking” is set as the amount of tracking until the “overload lower limit value” of the factor is detected. When the intermediate value between the overload lower limit value and the overload upper limit value is detected by applying the “minimum value in the expected tracking amount” as the amount of tracking when detecting the “overload upper limit value” of the cause As a memorial amount, a process of applying the “intermediate corresponding value” in a series of values maintaining a continuously decreasing relationship from the maximum value to the minimum value,
(3) If the detected value of the overload factor exceeds the “overload lower limit value” while pursuing the exhaust gas 4 supplied from the prime mover 7, “the prime mover at that time out of the expected amount of tracking” Of the intake air temperature and the detected value of the load ”and“ the memorized amount corresponding to the detected value of the overload factor among a series of values from the maximum value to the minimum value in the expected amount of tracking ” Of the fuel flow rate control valve 16 of the reheating burner 15 that raises the temperature of the exhaust gas 4 from the prime mover 7 so that it becomes the smallest remnant amount of “the amount” and “PID replenishment amount obtained by PID control”. While the opening degree is adjusted, the upstream side of the memorial burner 15 is adjusted so that the fresh air supply amount corresponding to the detected intake temperature and load value of the prime mover 7 at that time in the “new air supply expected amount”. A step of adjusting the discharge amount of the blower 19 for sending fresh air;
(4) When pursuing exhaust gas 4 by determining the amount of PID replenishment so as to keep the steam pressure of the boiler at the set pressure without mixing fresh air when exhaust gas 4 supplied from the prime mover 7 is exhausted In addition, when the “evaporation amount expansion requirement” based on the increase in steam consumption on the steam demand side is satisfied, fresh air is supplied to the exhaust gas 4 supplied from the prime mover 7 from that time, and based on the subsequent steam pressure Subsequently, “PID calculation” is performed to determine the amount of remembrance. When the “evaporation amount expansion requirement” is not satisfied, mixing of fresh air with the exhaust gas 4 supplied from the prime mover 7 is stopped, and thereafter And a process of determining the amount of remembrance by “PID calculation” on the basis of the vapor pressure.

In the above step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is the “expected amount of tracking when there is fresh air supply”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The process of (2) is performed when the overload factor is detected when a fresh air is supplied to perform the additional operation. The overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”. The lower limit is the “maximum allowable boiler operation temperature” and the “evaporation amount achievable with fresh air supply calculated according to the prime mover intake air temperature and load”, and the overload upper limit is determined in advance as the maximum allowable boiler operation temperature. "Exceeding maximum temperature" when the excess allowable temperature is added, and "Excessive maximum evaporation when there is fresh air supply" added to the predetermined allowable excess evaporation amount when the fresh air supply is present And
In the process (3), the reheating is performed by supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit value is “the maximum allowable boiler operation temperature” and “Evaporation amount achievable when fresh air is supplied” and the amount of memory that corresponds to the detected value of the engine intake air temperature and load at that time is The amount of memory corresponding to the detected value of the intake air temperature and load of the prime mover at that time.

In the above step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is the “expected amount of tracking when there is fresh air supply”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The process of (2) is performed when the overload factor is detected when a fresh air is supplied to perform a follow-up operation. The overload factor is “boiler inlet exhaust gas temperature” and the overload lower limit value is “boiler operation”. The maximum allowable temperature is the "maximum excess temperature", which is the maximum allowable temperature for boiler operation plus a predetermined excess allowable temperature.
The process (3) is performed by supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, the overload lower limit value is “the maximum allowable boiler operation temperature”, and The amount of tracking that corresponds to the detected value of the prime mover's intake air temperature and load at that time is “corresponding to the detected value of the prime mover's intake temperature and load at that time in the expected amount of tracking when fresh air is supplied” The amount of remembrance.

In the above step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is the “expected amount of tracking when there is fresh air supply”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The process of (2) is performed when the overload factor is detected when a fresh air is supplied to perform a follow-up operation. The overload factor is “boiler evaporation amount”, and the overload lower limit value is “at that time” `` Evaporation amount achievable with fresh air supply calculated according to prime mover intake air temperature and load '', and the overload upper limit value is set by adding a predetermined excess allowable evaporation amount to the achievable evaporation amount with fresh air supply Is the `` maximum evaporation amount when there is fresh air supply ''
The process (3) is carried out by supplying fresh air, the overload factor is “boiler evaporation”, and the overload lower limit value is “evaporation achievable when fresh air is supplied” Of the expected amount of remedy, the amount of remedy corresponding to the detected value of the intake air temperature and load of the prime mover at that time is `` the detected value of the prime mover intake temperature and load at that time of the expected amount of remedy when fresh air is supplied The amount of remembrance corresponding to "."

  “Evaporation amount expansion requirement is satisfied” in the step (4) is that the detected value of the boiler inlet exhaust gas temperature is equal to or higher than the “new air supply start temperature” that exceeds the maximum allowable boiler operation temperature by a predetermined amount. That is, “the requirement for expanding the amount of evaporation is no longer satisfied” means that the detected value of the boiler inlet exhaust gas temperature is determined in advance from the boiler inlet exhaust gas temperature corresponding to the detected prime temperature of the motor and the detected value of the load at that time. It will be below the “fresh air supply stop temperature”, which is less than that.

  “Evaporation amount expansion requirement is satisfied” in the step (4) is achieved when the detected value of the boiler evaporation amount is calculated in accordance with the intake air temperature and the load of the motor 7 at that time and when there is no fresh air supply This means that it exceeds the “fresh air supply start evaporation amount” that exceeds the possible evaporation amount by a predetermined amount. “The requirement for expansion of evaporation amount is no longer met” means that the detected value of the boiler evaporation amount is the supply of fresh air. It is below the “fresh air supply stop evaporation amount” which is higher than the achievable evaporation amount by the predetermined amount but is less than the fresh air supply start evaporation amount but less than the fresh air supply start evaporation amount.

  “Evaporation amount expansion requirement is satisfied” in the step (4) means that the detected value of the boiler vapor pressure is lower than the “new air supply start vapor pressure” which is lower than the set pressure by a predetermined amount. “Evaporation amount expansion requirement is not satisfied” means that the detected value of the boiler steam pressure is equal to or higher than the “new air supply stop steam pressure” which is higher than the set pressure by a predetermined amount.

  “Evaporation amount expansion requirement is satisfied” in the step (4) corresponds to the detected value of the intake air temperature and the load of the motor at that time in the estimated amount of PID tracking when no fresh air is supplied It means that it is equal to or more than the “fresh air supply start memorial amount” that is lower than the memorized amount by a predetermined amount. Of the expected time tracking amount, it is less than the amount of tracking that corresponds to the detected value of the engine intake air temperature and load at that time by a predetermined amount, but is smaller than the amount of fresh air supply starting tracking. It is to be less than the “volume”.

(1) Exhaust gas 4 generated according to several typical prime mover intake air temperatures during operation of the prime mover 7 and several typical loads at that time is determined in advance at the exhaust heat boiler inlet in calculation. In addition to calculating a group of “estimated tracking amounts” that do not exceed the “maximum allowable boiler operation temperature” and that generate a set pressure specific to the exhaust heat boiler, the “achievable evaporation amount” at this time is also calculated. The process of calculating,
(2) In case the detected value of the boiler overload factor corresponds to overload operation, the “maximum value in the expected amount of tracking” is set as the amount of tracking until the “overload lower limit value” of the factor is detected. When the intermediate value between the overload lower limit value and the overload upper limit value is detected by applying the “minimum value in the expected tracking amount” as the amount of tracking when detecting the “overload upper limit value” of the cause As a memorial amount, a process of applying the “intermediate corresponding value” in a series of values maintaining a continuously decreasing relationship from the maximum value to the minimum value,
(3) When the exhaust gas 4 supplied from the prime mover 7 is being pursued and the “overload lower limit value” is exceeded, “the detection of the intake air temperature and load of the prime mover at that time in the expected amount of follow-up” “A memorizing amount corresponding to the value”, “a memorizing amount given corresponding to the detected value of the overload factor among a series of values from the maximum value to the minimum value in the expected memorizing amount”, and “PID control” The opening degree of the fuel flow rate control valve 16 of the tracking burner 15 that raises the temperature of the exhaust gas 4 from the prime mover 7 is adjusted so that the amount of tracking is the smallest among the “PID tracking amount determined by the above”. It was made to comprise.

In step (1) above, the expected amount of remedy is “the expected amount of remedy when no fresh air is supplied” without mixing fresh air with the exhaust gas. Amount ",
The process of (2) is performed when the overload factor is detected during the refueling operation without supplying fresh air. The overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”. The lower limit values are the “maximum allowable boiler operation temperature” and the “evaporation amount achievable without fresh air supply calculated according to the prime mover intake air temperature and load”, and the overload upper limit value is determined in advance as the maximum allowable boiler operation temperature. In addition to the “exceeding maximum temperature” that is added to the specified excess allowable temperature, the “maximum maximum evaporation amount when there is no fresh air supply” is added to the achievable evaporation amount when no fresh air supply is added. Yes,
In the step (3), the reheating is performed without supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit value is “the maximum allowable boiler operation temperature” and The amount of evaporation that is achievable when there is no fresh air supply, and the amount of memory that corresponds to the detected intake temperature and load of the motor at that time is The amount of memory corresponding to the detected value of the intake air temperature and load of the prime mover at that time.

In step (1) above, the expected amount of remedy is “the expected amount of remedy when no fresh air is supplied” without mixing fresh air with the exhaust gas. Amount ",
The process of (2) is performed when the overload factor is detected during the refueling operation without supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “boiler operation” The maximum allowable temperature is the "maximum excess temperature", which is the maximum allowable temperature for boiler operation plus a predetermined excess allowable temperature.
In the process (3), the reheating is performed without supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, the overload lower limit value is “the maximum allowable boiler operation temperature”, and the expected amount of renewal The amount of tracking corresponding to the detected value of the engine intake air temperature and load at that time is `` the amount of tracking corresponding to the detected value of the engine intake air temperature and load at that time out of the estimated amount of tracking without fresh air supply ''. That is, “Small amount”.

In step (1) above, with the fresh air not mixed with the exhaust gas, the expected amount of remedy is "the expected amount of remedy when no fresh air is supplied", and the achievable evaporation amount is "achievable when no fresh air is supplied" The process of (2) is performed when the overload factor is detected in the memory operation without supplying fresh air, and the overload factor is the “boiler evaporation amount”. The value is “achievable evaporation amount without fresh air supply calculated according to the prime mover intake air temperature and load at that time”, and the overload upper limit value is predetermined as the achievable evaporation amount without fresh air supply. It is the “maximum excess evaporation amount when there is no fresh air supply”, with the excess allowable evaporation amount added.
In the process (3), reheating is performed without supplying fresh air, the overload factor is “boiler evaporation”, and the lower limit of overload is “evaporation that can be achieved without supply of fresh air”. The amount of remedy that corresponds to the detected value of the intake air temperature and load of the motor at that time is `` the expected amount of remedy when no fresh air is supplied is the detected value of the intake air temperature and load of the motor at that time. '' The amount of remembrance corresponding.

  In the exhaust heat boiler, in order to keep the hot water / hot oil at a set temperature instead of the steam generating boiler, the amount of exhaust gas 4 to be added is determined by PID control based on the detected hot water / hot oil temperature. In any of the above configurations, for hot water and hot oil formed by replacing the amount of evaporation with hot water and hot oil, replacing steam with hot water and hot oil, and pressure with the temperature of hot water and hot oil. This is a waste heat boiler.

  According to the first aspect of the present invention, when a cogeneration system is planned, an exhaust heat boiler having an ability to exceed the amount of evaporation that can be generated by tracking exhaust gas is selected. In addition, it is possible to meet the demand for an excessive amount of evaporation exceeding the plan at the time of planning from the steam demand side. In other words, if the blower is not operated, it will be operated only by purging the exhaust gas from the power generation device, and if the blower is operated, fresh air is mixed with the exhaust gas and the amount of renewal is increased. An allowable maximum evaporation amount that can be exerted or an amount close thereto can be generated. Even if an overload factor of the boiler occurs during the operation to expand the evaporation amount, the suppression memorizing amount is selected in consideration of the prime mover intake air temperature and the load of the power generator, and the boiler is designed to escape from the overload. Is protected. At this time, since it does not drop to the minimum amount of boiler operation, the amount of evaporation does not decrease or fluctuate, so that there is no sudden modulation or confusion in the operation on the steam demand side. I can leave. As a general rule, the operation for suppressing the amount of remedy should be performed once after overload, the control itself is simplified, and malfunctions are reduced as much as possible.

  According to Claims 2 to 4, it is possible to escape from overheating of the boiler heat transfer tube, which is an overload factor, and excessive evaporation, by calculating the amount of restraint pursuit based on the factor, and to escape by extremely simple control. Can do. In particular, in the case of claim 2, even if there is an unreliable situation in the exhaust gas temperature sensor or the steam flow meter, the monitoring is performed by two different overload factors, and the reliability of the control can be improved. it can.

  According to claims 5 to 8, in order to respond to the increase in consumption on the steam demand side, the presence or absence of the requirement is grasped in order to expand the evaporation amount, and the energy saving operation when the evaporation demand is not required and the evaporation amount need not be increased. Transition is made smoothly without chattering.

  According to the ninth aspect of the present invention, there is no evaporation amount expansion operation because the blower is not operated. However, even if an overload factor of the boiler occurs, the suppression memorization amount is set so as to escape from the overload. In consideration of the prime mover intake air temperature and load of the power generator, it can be determined within the scope of boiler protection operation. In this case as well, it is possible to prevent the operation on the steam demand side from being confused due to rapid fluctuations without dropping to the minimum amount of boiler operation. As a general rule, the memory amount suppression operation is executed once after overloading, and it is not necessary to repeat the control.

  According to the tenth to twelfth aspects, overheating of the boiler heat transfer tube, which is an overload factor, and escape from excessive evaporation are dealt with with a minimum amount of remediation based on the factor, and are executed with a simple control system. can do. In particular, in the case of claim 10, even if the exhaust gas temperature sensor and the steam flow meter have unreliable circumstances, they are watched by two overload factors, and improvement in control reliability is expected.

  The invention of claim 13 points out that in any of the above-mentioned inventions, it can be applied to a hot water / hot oil generating boiler instead of a steam generating exhaust heat boiler. ing.

1 is an overall conceptual diagram of a cogeneration system to which an exhaust gas tracking control method according to the present invention is applied. The block diagram showing exhaust gas tracking control. Data prepared in the first step (1) applied to the blower always stop mode or the blower non-equipment system (Table 1). Data prepared in the first step (1) applied to the blower continuous operation mode and the blower operation stop automatic switching mode (Table 2). Operation modes, forms constituting them, and derivation modes for each amount of memory (Table 3). Operation mode and its inclusion process (Table 4). The fan non-equipment system figure which enabled only the fan always stop mode. The control block diagram of the form A in the fan non-equipment system which enabled execution only of the fan always stop mode. The control block diagram of the form B in a fan non-equipment system. (A) is a graph showing the expected value of the intake amount depending on the prime mover intake temperature and load in Table 1, and (b) is the expected value of the follow up amount dependent on the prime mover intake temperature and load in Table 2. Graph. (A) is a graph as a suppression tracking amount calculation chart caused by the boiler inlet exhaust gas temperature in the blower always stopped mode, and (b) is a graph as a suppression tracking amount calculation chart caused by the boiler evaporation amount. Flow for selecting the amount of remedy for boiler overload escape in the blower always-stop mode or the system without a blower. Combination of inclusion processes of form A & B in blower always stop mode (Table 5). (A) is a graph as a chart for calculating the amount of restraint tracking due to the boiler inlet exhaust gas temperature in the fan normal operation mode and the fan operation stop automatic switching mode, and (b) is for calculating the amount of suppression tracking due to the amount of boiler evaporation. Graph as a chart. Flow of selecting the amount of remedy for boiler overload in the fan normal operation mode and the fan operation stop automatic switching mode. The control block diagram of the form F which performs an air blower regular operation mode. Combinations of inclusion processes of form F & G in the blower continuous operation mode (Table 6). Combination of inclusion processes of forms C and D & E in blower operation stop automatic switching mode (Table 7). The control block diagram of the form G which performs an air blower regular operation mode. The control block diagram of the form C which performs blower operation stop automatic switching mode. The control block diagram of the form D which performs blower operation stop automatic switching mode. The control block diagram of the form E which performs the overload suppression of an air blower operation stop automatic switching mode. The flowchart of the whole tracking amount control. Structure example of mode selection switch. Flow for determining whether or not the requirements for boiler overload escape operation application are satisfied. The control block diagram of form A which performs blower always stop mode. The control block diagram of form B which performs blower always stop mode. A flow for determining whether or not the requirements for operation with fresh air supply are satisfied (switching to expansion of evaporation). A flow for determining whether or not the requirement for canceling operation application with fresh air supply is satisfied (reverse from expansion of evaporation). The control block diagram of the waste-heat boiler independent operation (form H) performed in the air blower operation mode in a power generation device stop. A ready-made example of a cogeneration system.

  Hereinafter, an exhaust gas tracking control method in a cogeneration system according to the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 shows a cogeneration system in which a power generator 1 and a waste heat boiler 2 are combined, and FIG. 2 is a detailed explanation of the configuration of the control unit. As shown in FIG. 1, an exhaust gas circulation duct 3 is provided between the power generation device and the exhaust heat boiler. A fresh air supply device 6 that mixes fresh air (fresh air) 5 taken from the atmosphere into the exhaust gas 4 is provided in this duct. Is also attached.

The power generation apparatus 1 described above includes a prime mover 7 such as a gas turbine, a gas engine, or a diesel engine, and a generator (generator) 8 driven thereby. The exhaust gas discharged from the prime mover has high thermal energy, which is supplied to the exhaust heat boiler 2 to generate high-temperature and high-pressure steam 9. It is inevitable that the stored energy of the exhaust gas depends on the intake air temperature of the prime mover 7, the prime mover load, or the generator load. Therefore, for example, the 13A natural gas 10 is combusted to exhaust the exhaust gas 4 to compensate the amount of supplied heat energy. In the boiler, the steam pressure in the steam drum 11 or a header that performs the same function is detected, and PID calculation is performed based on the detected steam pressure, and the steam pressure is kept at a set pressure (ordinary pressure), for example, 1.27 MPa. As described above, the amount of remedy in the introduced exhaust gas (hereinafter referred to as “PID remedy amount (unit: Nm ³ / h)”) is determined.

  Incidentally, the power generator 1 is provided with an intake air temperature sensor 12 for detecting the intake air temperature of the prime mover and a load sensor 13 for detecting the load of the prime mover or the generator. Both are well known and will not be described in detail. The remedy device 14 comprises a remedy burner 15 and a fuel flow control valve 16, and the flow rate is detected by a fuel flow meter 17 and fed back, and the control valve opening is adjusted so that a desired remedy amount is achieved. The The fresh air supply device 6 includes a fresh air mixing box 18, a blower 19 that takes in and supplies outside air, and an electric motor 20 that drives the blower 19. The air flow rate adjustment is performed by adjusting the opening degree of the fresh air supply amount control valve 21 or by controlling the motor rotation speed by inverter control (frequency variable adjustment). The exhaust heat boiler has a temperature sensor 22 that detects the temperature of the exhaust gas at the inlet, a sensor 23 that detects the pressure in the drum 11 that temporarily stores the generated steam, and a steam consuming facility (hereinafter referred to as “steam demand side”) 24. A steam flow meter 25 for detecting the outflow amount is provided.

  In such a cogeneration system, an exhaust heat boiler that has sufficient steam generation capacity to satisfy the required evaporation amount on the steam demand side is adopted. An example is given when the motor intake air temperature is 15 ° C. and the motor load is 75%. At this time, if the evaporation amount requirement at the time of planning on the steam demand side is 26.0 t / h, this can be generated without supplying fresh air to the exhaust gas, “Achievable evaporation amount without supply of fresh air” An exhaust heat boiler that makes this possible and is one rank higher is selected. If fresh air is mixed with the exhaust gas from such an exhaust heat boiler and the amount of renewal is increased, the “evaporation amount achievable when fresh air is supplied” is 30.3 t / h. This is the maximum allowable evaporation amount. The prime mover intake air temperature and load as operating conditions, and the amount of tracking and the amount of evaporation at that time will be described in detail later in Tables 1 and 2 shown in FIGS.

  In such a waste heat boiler 2, eight operation modes from A to H are possible as classified in Table 3 of FIG. Among them, the form A and the form B belong to a “blower always stopped” mode in which fresh air is not mixed with exhaust gas. Form C, Form D, and Form E constitute a “blower operation stop automatic switching” mode in which fresh air is not mixed or mixed with exhaust gas. Forms F and G form a “blower continuous operation” mode in which fresh air is mixed with exhaust gas. Both are operations in a state where the power generation device is operated, and the operation is linked with the power generation device and the exhaust heat boiler. Form H is a “boiler independent operation” mode in which hot air is generated by supplying fresh air in a state where the power generator is not operated, that is, in a state where there is no exhaust gas, to obtain steam.

  Hereinafter, specific description will be given in detail using numerical values at a prime mover intake air temperature of 15 ° C. and a prime mover load of 75%. Form A (see FIG. 26 to be described later) is an operation in a state where exhaust gas is being chased and in a state that does not reach the overload protection of the boiler. Form B (see FIG. 27 to be described later) provides boiler protection as a result of overloading such as overheating of the heat transfer tubes and excess evaporation caused by excessive replenishment in response to an increase in steam consumption during operation of form A. It is a driving that aims to break away from it.

  In form A, the amount of tracking is determined by PID control based on the vapor pressure of the drum or the like, but in form B, the amount of tracking is determined (selection of the minimum amount of tracking) described in detail later according to the present proposal. . In any form, since the blower is stopped, the maximum evaporation amount (evaporation amount achievable when no fresh air is supplied) achieved by simply pursuing the exhaust gas supplied from the power generator is 26.0 t at the time of planning. / H. Therefore, even if the exhaust heat boiler has sufficient steam generation capacity, the evaporation amount is limited to 27.5 t / h at the maximum, and the allowable maximum evaporation amount inherent in the exhaust heat boiler (evaporation amount achievable with fresh air supply) ) Of 30.3 t / h)).

  In the “Blower operation stop automatic switching” mode of modes C, D and E, the operation and stop of the blower are automatically switched, and before switching, the “evaporation amount achievable without fresh air supply” of 26.0 t / h is set. After switching, it is possible to realize 30.3 t / h of the “evaporation amount achievable when fresh air is supplied”, and it is possible to escape from overload after switching. . Stated individually, Form C (see FIG. 20 described later) is an operation when the exhaust gas is not mixed with the exhaust gas and is in a state where it is not possible to protect the boiler without overloading. This is substantially the same as Form A.

  In form D (see FIG. 21 described later), the boiler is overloaded during operation of form C, or in response to a request for increasing the amount of evaporation from the steam demand side, the blower is turned after that point to fresh air to the exhaust gas. In this operation, mixing is performed and the amount of evaporation is increased. Therefore, direct boiler protection as in form B is not performed. It goes without saying that overheating of the heat transfer tube is substantially eliminated because the exhaust gas temperature at the boiler inlet is lowered by the supply of fresh air. In the operation of the form D, the PID control is performed so that the pressure of the steam drum recovers and maintains the normal pressure, and the fuel gas is combusted so that the amount of renewal calculated based on the PID control.

  The exhaust gas temperature rises due to the amount of replenishment that increases during such operation, and an evaporation amount exceeding 30.3 t / h of the “evaporation amount achievable when fresh air is supplied” is generated or the boiler heat transfer tube is May exceed 850 ° C. At this time, it is necessary to enter the boiler protection operation, which is the operation of the form E (see FIG. 22 described later). Form E has the same purpose as Form B described above, and is an escape operation from overload. Therefore, the memorial amount follows the memorial amount determination process according to this proposal. In these forms D and E, the blower is driven, and the air flow is adjusted so as to correspond to the prime mover intake air temperature and the load at that time. By the way, “automatic switching” in the “automatic blower operation stop switching” mode means that the blower is turned to automatically shift to the form D, and the blowing is stopped during the operation of the form D and automatically returned to the form C. The transition to the control mode E for boiler protection is not included in the concept of “switching” here. Note that switching is performed when an “evaporation amount expansion requirement” described later is satisfied or not satisfied.

  Form F (see FIG. 16 to be described later) is the same as form D, and the supply of fresh air and the increase in the amount of remembrance are achieved. In the operation during this period, the amount of memory is calculated so that the drum pressure maintains the normal pressure by PID control. Form G (see FIG. 19 to be described later), like Form E, generates an evaporation amount exceeding the allowable maximum evaporation amount of 30.3 t / h, or the boiler heat transfer tube exceeds 850 ° C. It is placed in a state that must be protected, and the amount of remembrance follows the remedy amount determination process according to this proposal. In either case, the air blower is driven, and the air flow is adjusted according to the prime mover intake air temperature and the load at that time.

  Form H (see FIG. 30 described later) is a case in which outside air is introduced in a state where the power generation device is stopped, that is, in a state where exhaust gas is not supplied, and fuel is burned with this air. It is an operation in the case of “I do not need power generation, but I want only steam”. Needless to say, the operation is based on PID control. In this case, the heat transfer tube does not overheat or exceed the capacity in principle, but in the unlikely event that it occurs, measures such as immediately stopping the operation of the boiler are taken. The blower is operated at a uniform number of rotations, so that the amount of blown air is constant, but may be adjusted.

Returning to FIG. 1, in the upper half, the control means that enables not only a series of operations of forms C, D, and E but also operation of the remaining five forms is an aggregate of blocks. It is represented. Needless to say, it is formed by a microcomputer or the like, and executes exhaust gas tracking control according to the present invention. The details of this control system are shown in FIG. 2, which has already been mentioned, but the elements in both figures do not necessarily appear as devices, but are conceptually shown to facilitate understanding of control development. In order to realize the control operation, it is at least potentially present. This memorizing amount calculation control means 26 calculates the memorizing amount required at that time based on the detection signals from the exhaust gas temperature sensor 22, the drum pressure sensor 23, and the steam flow meter 25 described above. A signal that defines the amount of combustion (Nm ³ / h) necessary for pursuing gaseous fuel such as 13A natural gas is output. In addition, when the blower 19 is operated, an opening degree signal of the fresh air supply amount control valve 21 or a speed control signal of the blower drive motor 20 is output so as to define the amount of fresh air 5 mixed with the exhaust gas 4. (The fresh air supply control valve is not shown in FIG. 2). The sensors 22, 23, 25, the intake air temperature sensor 12, and the load sensor 13 are collectively shown in the “driving current detection unit” shown on the left side in FIG. 2.

  A control panel (not shown) for operating the tracking amount calculation control means 26 is provided with an input unit 27 for inputting data necessary for tracking control in advance, and a data storage in which the input values are stored. The data to be used or referred to is extracted from the unit 28, and the amount of remedy is calculated while comparing with the above detection signal. First, a PID control unit 29 and a fuel amount adjustment command unit 30 are provided in order to control the amount of tracking based on the pressure signal from the drum pressure sensor 23 when in the form C and the form D. In addition to this, in order to perform the control of the present invention, a form change determination unit 31, an output value determination unit 32, and an output value command unit 33 are prepared, which are also shown in FIG. 1 and FIG.

  The form change determination unit 31 is provided with a fresh air supply necessity determination unit 34 and a boiler overload escape operation application necessity determination unit 35, and an information transmission change unit 36 is added to the latter. The output value determination unit 32 is provided with an overload tracking amount selection unit 37 and a fresh air supply amount reading unit 38, and the former includes an overload tracking amount calculation unit 39 and any additional tracking amount for each factor of boiler protection. A minimum amount-of-track selection unit 40 that determines whether to use the amount of dredging is included. The output value command unit 33 is provided with a fresh air supply command unit 41 in addition to the fuel amount adjustment command unit 30 described above. Incidentally, the fuel amount adjustment command unit 30 is also instructed to transmit not only the PID control unit 29 but also the tracking amount from the minimum tracking amount selecting unit 40 required for the boiler protection operation.

Here, the outline of the steps adopted to cover the “blower always stop” mode, the “blower operation stop automatic switching” mode, and the “blower always operate” mode except for the form H will be described. Each mode will selectively employ some of the processes. Overall, there are four main processes. that is,
(1) Exhaust gas generated according to some typical prime mover intake air temperatures during operation of the prime mover and several typical loads at that time is calculated in advance at the exhaust heat boiler inlet. Calculate a group of “expected memorization amount” that generates a set pressure (ordinary pressure) of 1.27 MPa that is within a range that does not exceed the “operating maximum allowable temperature”, for example, 850 ° C., and that is unique to the exhaust heat boiler. A process to calculate the "achievable evaporation"
(2) In case the detected value of the boiler overload factor corresponds to overload operation, the “maximum value in the expected amount of tracking” is set as the amount of tracking until the “overload lower limit value” of the factor is detected. When the intermediate value between the overload lower limit value and the overload upper limit value is detected by applying the “minimum value in the expected tracking amount” as the amount of tracking when detecting the “overload upper limit value” of the factor As a memorial amount, a process of satisfying the “intermediate corresponding value” in a series of values maintaining a continuously decreasing relationship from the maximum value to the minimum value,
(3) When the exhaust gas supplied from the prime mover is being pursued, if the detected value of the overload factor exceeds the “overload lower limit value”, “the intake air of the prime mover at that time out of the expected amount of follow-up “Amount of memory corresponding to the detected value of temperature and load” and “Amount of memory given corresponding to the detected value of the overload factor among a series of values from the maximum value to the minimum value in the expected amount of tracking” And the opening degree of the fuel flow rate control valve of the tracking burner that raises the temperature of the exhaust gas from the prime mover is adjusted so as to be the smallest amount of the “PID tracking amount determined by PID control”. Process,
(4) When the exhaust gas supplied from the prime mover is not being mixed with fresh air and the steam pressure of the PID is determined in order to keep the steam pressure of the boiler at the set pressure, Based on the increase in steam consumption on the demand side, when the “evaporation amount expansion requirement is met”, fresh air is supplied to the exhaust gas supplied from the prime mover from that point, and “PID calculation” continues based on the subsequent steam pressure. After that, when the amount of remedy is determined and “the requirement for expansion of evaporation is no longer met”, the mixing of fresh air with the exhaust gas supplied from the prime mover is stopped and the subsequent steam pressure is used. A step of determining the amount of remembrance by PID calculation;
It is.

Each of the main processes described above includes several sub processes. For example, the sub process in the main process (1) is represented by (1-i). Note that i = 1, 2,. The following shows the sub-step, which is also simply referred to as a step in the present invention. By the way, each process is expressed in a very simplified manner, but the substance of each process is in each of the corresponding processes in the “Blower always stop” mode, “Blower always run” mode, and “Blower stop automatic switching” mode, which will be described later. I will list them.
(1-1) In a state where fresh air is not mixed with the exhaust gas, the expected amount of remedy is “the expected amount of remedy when no fresh air is supplied”, and the achievable amount of evaporation is “the amount of evaporation achievable when no fresh air is supplied” And
(1-2) In a state where fresh air is mixed with exhaust gas, the expected amount of tracking is the “estimated amount of tracking when there is fresh air supply”, and the achievable evaporation amount is “achievable evaporation when there is fresh air supply” In addition, the “expected amount of fresh air supply” that is necessary for the “forecast amount for when fresh air is supplied” is also calculated.
(2-1) The overload factor is detected when the regenerative operation is performed without supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “the maximum allowable boiler operation”. The temperature is 850 ° C., and the overload upper limit value is “excess maximum temperature” 900 ° C. obtained by adding, for example, 50 ° C. of the predetermined “excess allowable temperature” to the boiler operation allowable maximum temperature.
(2-2) The overload factor is detected when fresh air is supplied to perform a follow-up operation. The overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “the maximum allowable boiler operation”. The temperature is 850 ° C., and the overload upper limit value is “excess maximum temperature” 900 ° C. obtained by adding, for example, 50 ° C. of the predetermined “excess allowable temperature” to the boiler operation allowable maximum temperature.
(2-3) The overload factor is detected when the vehicle is operated without supplying fresh air, the overload factor is “boiler evaporation”, and the overload lower limit value is “the prime mover intake at that time” "Evaporation amount achievable without fresh air supply" calculated according to the temperature, for example, 15 ° C and the prime mover load, for example, 75%, and the overload upper limit value is determined in advance as an achievable evaporation amount without the fresh air supply. “Excessive maximum evaporation amount when no fresh air is supplied” is 27.5 t / h, for example, 1.5 t / h added to “excess allowable evaporation amount”.
(2-4) The overload factor is detected when a fresh air is supplied to perform a follow-up operation. The overload factor is “boiler evaporation amount”, and the overload lower limit value is “the prime mover at that time” "Evaporation amount achievable with fresh air supply" calculated according to the intake air temperature, eg, 15 ° C and load, eg, 75% ", and the overload upper limit value is determined in advance as the achievable evaporation amount with fresh air supply. “Excessive maximum evaporation amount when fresh air is supplied” is 27.5 t / h, for example, 1.5 t / h added to “excess allowable evaporation amount”. (3-1) Reheating is performed without supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, the overload lower limit value is “maximum allowable boiler operation temperature”, The amount of tracking that corresponds to the detected value of the intake air temperature and load of the prime mover at that time is “the amount of tracking that corresponds to the detected value of the intake air temperature and load of the prime mover of the estimated amount of tracking when no fresh air is supplied” Amount ".
(3-2) Reheating is performed without supplying fresh air, the overload factor is “boiler evaporation”, and the lower limit of overload is “evaporation amount achievable without supplying fresh air”. The amount of tracking that corresponds to the detected value of the prime mover's intake air temperature and load at that time is `` corresponding to the detected value of the prime mover's intake temperature and load at that time among the expected amount of tracking without fresh air supply The amount of remembrance performed.
(3-3) Reheating is performed without supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit values are “maximum allowable boiler operation temperature” and “new boiler operation temperature”. Evaporation amount achievable when there is no air supply ”, and the amount of memory that corresponds to the detected value of the engine intake air temperature and load at that time is the value of Of these, the amount of memory corresponding to the detected value of the intake air temperature and load of the prime mover at that time.
(3-4) Reheating is performed by supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “maximum allowable boiler operation temperature”. The amount of tracking that corresponds to the detected value of the intake air temperature and load of the prime mover at that time is “the amount of tracking that corresponds to the detected value of the intake air temperature and load of the prime mover of the estimated amount of tracking when fresh air is supplied” In addition, the amount of fresh air to the upstream side of the combustor burner is adjusted so that it becomes “the amount of fresh air supply corresponding to the detected intake air temperature and load of the prime mover at that time”. The discharge amount of the blower that feeds the air is adjusted by the opening degree of the fresh air supply amount control valve, or the air amount is adjusted by inverter control of the blower motor.
(3-5) Reheating is performed by supplying fresh air, the overload factor is “boiler evaporation”, and the lower limit of overload is “evaporation amount achievable when fresh air is supplied”. The amount of tracking that corresponds to the detected value of the prime mover's intake air temperature and load at that time is `` corresponding to the detected value of the prime mover's intake temperature and load at that time in the estimated amount of tracking when fresh air is supplied In addition, the upstream side of the memorial burner so that it becomes the “fresh air supply amount corresponding to the detected intake air temperature and load of the prime mover at that time among the expected fresh air supply amount”. The discharge amount of the blower that sends fresh air into the air is adjusted by the opening degree of the fresh air supply amount control valve, or the air amount is adjusted by inverter control of the blower motor.
(3-6) Reheating is performed by supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit values are “maximum allowable boiler operation temperature” and “new boiler operation temperature”. Evaporation amount achievable with air supply ”, and the amount of memory that corresponds to the detected value of the engine intake air temperature and the load at that time is the value of In addition, the amount of compensation corresponding to the detected value of the intake air temperature and load of the prime mover at that time, in addition to the new amount corresponding to the detected value of the intake air temperature and load of the prime mover at that time of the expected amount of fresh air supply The discharge amount of the blower that sends fresh air to the upstream side of the combustor burner is adjusted by the opening degree of the fresh air supply amount control valve, or the air amount is adjusted by inverter control of the blower motor so as to be “air supply amount”.
(4-1) “Evaporation amount expansion requirement is satisfied” means that the detected value of the boiler inlet exhaust gas temperature exceeds the maximum allowable boiler operation temperature of 850 ° C. by a predetermined 20 ° C. It is to be 870 ° C. or higher. “Evaporation amount expansion requirement is not satisfied” means that the detected value of the boiler inlet exhaust gas temperature corresponds to the detected value of the motor intake air temperature 15 ° C. and the load 75% at that time, the boiler inlet exhaust gas temperature 806 ° C. (Table 2). The new air supply stop temperature is 781 ° C. or lower, which is lower by a predetermined 25 ° C. than the reference number 8). As a result, the “changed evaporation amount requirement” is canceled, and the changed form is released.
(4-2) “Evaporation amount expansion requirement is satisfied” means that the detected value of the boiler evaporation amount (steam outflow amount) is calculated according to the motor intake air temperature at that time, for example, 15 ° C. and the load 75%. Evaporation amount achievable without fresh air supply, for example, “new air supply start evaporation amount” 26.3 t / h, which exceeds a predetermined amount of 0.3 t / h from 26.0 t / h (see number 8 in Table 1) “The evaporation amount expansion requirement is no longer satisfied” means that the detected value of the boiler evaporation amount (steam outflow amount) is from the evaporation amount achievable when no fresh air is supplied, for example, 26.0 t / h. This is a “fresh air supply stop evaporation amount” of 26.1 t / h or less, which is less than the 26.3 t / h of the “fresh air supply start evaporation amount”, but exceeds a predetermined amount.
(4-3) “Evaporation amount expansion requirement is satisfied” means that the detected value of the boiler vapor pressure is lower than the set pressure of 1.27 MPa by a predetermined amount of 0.1 MPa, “fresh air supply start vapor pressure” 1 .17 MPa or less, and “the requirement for increasing the amount of evaporation cannot be satisfied” means that the detected value of the boiler steam pressure exceeds the set pressure by a predetermined amount of 0.1 MPa. The pressure is 1.37 MPa or more.
(4-4) “Evaporation amount expansion requirement is satisfied” means that the PID tracking amount is the detected value of the motor intake air temperature 15 ° C. and the load 75% of the expected tracking amount when there is no fresh air supply. The amount of remedy is 910 Nm ³ / h or more, which is lower than the corresponding amount of remedy 920 Nm ³ / h (see number 8 in Table 1) by a predetermined amount 10 Nm ³ / h, “Evaporation amount expansion requirement is not satisfied” means that the PID tracking amount is the amount of tracking 920 Nm ³ corresponding to the detected value of the intake air temperature and load of the prime mover among the expected tracking amount when there is no fresh air supply Is less than a predetermined amount, but is less than the “fresh air supply start tracking amount” 900 Nm ³ / h or less.

  Of these processes, those related to form A & B will be described first in the "Blower Continuous Stop" mode, followed by "Blower Continuous Operation" mode consisting of Form F & G, and "Blower Stop Automatic" consisting of Form C, D & E. The “switch” mode is described after that. First, in explaining the forms A & B, the steps appearing there are shown. B of the forms A & B is an overload escape operation when there is no fresh air supply, and this is the first (1-1) step, the (2-1) step, and / or as shown in Table 4 of FIG. The (2-3) step is required, and the (3-1) step, the (3-2) step, and the (3-3) step require at least one of them. Note that Form A is a non-overload operation when no fresh air is supplied and does not require the (3-1) step, (3-2) step, and (3-3) step. -1) The process, the (2-1) process, and the (2-4) process are not necessary, but needless to say, they are indispensable for preparing for the form B.

  In the power generation device, the amount of tracking and the amount of boiler evaporation achieved thereby differ depending on which is the prime mover intake air temperature or the load. The first (1-1) process includes “the expected exhaust amount of exhaust gas when no fresh air is supplied for each engine intake air temperature and load”, and “no fresh air supply” that is the amount of boiler evaporation. Is calculated. More specifically, the exhaust gas generated in response to several typical prime mover intake temperatures during operation of the prime mover and several typical loads (which may be generator loads) at that time, In the range in which the maximum allowable boiler operation temperature at the inlet of the exhaust heat boiler, for example, does not exceed 850 ° C., and the set pressure unique to the exhaust heat boiler, for example, 1.27 MPa, is calculated. A group of “expected pursuit amount when there is no fresh air supply” and “achievable evaporation amount when there is no fresh air supply” are calculated.

  The data is shown in Table 1 of FIG. This is obtained by heat calculation such as heat transfer and heat loss, and the accuracy is enhanced by correcting and supplementing with data collected during trial operation. The following description will be made with reference to FIGS. 7, 8 and 9 which are made easy to understand by removing elements not corresponding to the forms A & B in FIGS. Data as shown in Table 1 is accumulated in the data storage unit 28 of the tracking amount calculation control means 26 from the system data input unit 27 in the figure. Among these data, what should be input by all means are the intake air temperature, the load factor, the calculated expected amount of tracking, the boiler inlet exhaust gas temperature, and the achievable evaporation amount. The motor exhaust gas amount and the motor exhaust gas temperature are provided by the design group of the power generator, and the exhaust gas that has been tracked after considering these and heat loss in the gas distribution system is the maximum allowable temperature for boiler operation. There is a need for an expected amount of remedy that is within 850 ° C. and that can maintain the normal pressure of the exhaust heat boiler 1.27 MPa. The amount of evaporation generated according to this is calculated as “amount of evaporation achievable without fresh air supply”. Incidentally, for example, the amount of compensation for the intake air temperature obtained using the load as a parameter is stored in the form shown in FIG. 10A, and the amount of compensation for any intake air temperature or power generation load is interpolated on each line. It will be given in points or extrapolated points.

In the (2-1) step, the “excess temperature range restraint memorizing amount” calculation chart as the restraint memorizing amount in the zone exceeding the “boiler operation allowable maximum temperature 850 ° C.” when there is no fresh air supply, -1) Automatically generated based on data obtained in the process. More specifically, when the regenerative operation is performed without supplying fresh air, the detected value of the exhaust gas temperature at the boiler inlet is, for example, 50 of the “excess allowable temperature” that is predetermined from the maximum allowable boiler operation temperature of 850 ° C. “Excessive maximum temperature” with an additional ℃. In the case of any temperature in the zone up to 900 ℃, as the amount of remedy until the maximum allowable boiler operation temperature is detected. As the maximum value, the remedy amount of 1,287 Nm ³ / h in No. 5 in Table 1 of FIG. 3 is used, and as the amount of remedy when the excess maximum temperature is detected, the amount of remedy when no fresh air is supplied As the minimum amount, the amount of remedy 571 Nm ³ / h in number 16 in the same table is satisfied, and the amount of remedy when the intermediate temperature is detected is continuously reduced from the maximum value to the minimum value. To a series of values To create a chart that was set to the devote an intermediate corresponding value. This is stored in the form shown in FIG. 11A, and is arbitrarily given by an interpolation point on each line. The series of values may be on a straight line, but may be applied on a gradually decreasing line other than the straight line. Incidentally, among the data obtained in the (1-1) step, the above-mentioned maximum and minimum values and the values between them are used to determine the amount of suppression and tracking within the operating conditions conceivable for the power generator. This is because the exhaust heat boiler is operated within the range, and the heat balance between the power generation device and the exhaust heat boiler is easily maintained, and it is possible to keep the generated evaporation from drastically decreasing. Based on knowledge.

In the second (2-3) step, a chart for calculating the “excess evaporation amount region suppression tracking amount” calculation chart as the suppression tracking amount in the band exceeding the “evaporation amount achievable without fresh air supply 26.0 t / h” (1-1) Automatically generated based on the data obtained in the process. More specifically, when the refueling operation is performed without supplying fresh air, the detected value of the boiler evaporation amount (steam outflow amount) depends on the prime mover intake air temperature, for example, 15 ° C. and the load, for example, 75%. “Maximum excess when no fresh air is supplied”, for example, 1.5 t / h of the “excess permissible evaporation” determined in advance from the calculated evaporation amount 26.0 t / h when no fresh air is supplied Supplying fresh air as a commemoration amount until it detects an evaporation amount of 26.0 t / h that is achievable when there is no fresh air supply, in preparation for when the evaporation amount is in any of the zones up to 27.5 t / h In addition to satisfying the above-mentioned 1,287 Nm ³ / h, which is the maximum value in the expected amount of remedy when there is none, the minimum value in the expected amount of remedy when there is no fresh air supply as the amount of remedy when the excess maximum evaporation amount is detected devotes 571 nm ³ / h as described above, it detects the intermediate evaporation The add 焚量 time was to create a chart so devote corresponding values of the intermediate in a series of values maintaining the relationship that decreases continuously to the minimum value from the maximum value. This is stored in the form shown in (b) of FIG. 11, and is arbitrarily given by an interpolation point on each line. In this case as well, the series of values is not limited to those on a straight line, but may be those on a gradually decreasing line other than the straight line.

The (3-1) step and the (3-2) step will be described later, and the (3-3) step will be described later. In this process, of the overload suppression memorial amount when there is no fresh air supply,
"Estimated amount of remembrance when no fresh air is supplied" determined in step (1-1)
“Excessive temperature range restraint memorial amount” obtained in step (2-1)
“Excess evaporation amount area suppression memorial amount” obtained in the second (2-3) step
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. More specifically, when the exhaust gas supplied from the prime mover is operated without being mixed with fresh air, the detected value of the boiler inlet exhaust gas temperature exceeds the maximum allowable boiler operation temperature of 850 ° C. and the boiler evaporation amount When the detected value exceeds the achievable evaporation amount of 26.0 t / h when there is no fresh air supply, the memorization corresponding to the detected value of the intake air temperature and the load of the prime mover at that time out of the expected memorized amount when there is no fresh air supply Corresponds to the detected value of the boiler inlet exhaust gas temperature among a series of values from the maximum value of 1,287 Nm ³ / h mentioned above to the minimum value of 571 Nm ³ / h mentioned above in the expected amount of commemoration when no fresh air is supplied The detection value of the boiler evaporation amount among a series of values from the maximum value of 1,287 Nm ³ / h to the minimum value of 571 Nm ³ / h in the expected amount of tracking when no fresh air is supplied The amount of remembrance and vapor pressure given correspondingly Since the opening degree of the fuel flow control valve of the tracking burner that raises the temperature of the exhaust gas from the prime mover is adjusted so as to be the smallest amount of PID tracking by the PID control that is always performed. is there.

Next, it will be specifically described. Assume that the motor intake air temperature is 15 ° C. and the load is 75%. At this time, “the amount of remedy corresponding to the detected value of the intake air temperature and the load of the prime mover among the expected amount of remedy when there is no fresh air supply” is 920 Nm ³ / h in number 8 of Table 1. This can also be read from FIG. Assuming that the detected value of the boiler inlet exhaust gas temperature is 870 ° C., which exceeds the maximum allowable boiler operation temperature of 850 ° C., “from the maximum value 1,287 Nm ³ / h in the expected amount of tracking without fresh air supply to the minimum value 571 Nm ³ Of the series of values up to / h, corresponding to the detected value of the exhaust gas temperature at the boiler inlet ”is 1,001 Nm ³ / h when the gradual decrease line in FIG. . Next, assuming that the detected value of the boiler evaporation amount is 26.9 t / h exceeding the achievable evaporation amount 26.0 t / h when there is no fresh air supply, In the series of values from the maximum value of 1,287 Nm ³ / h to the minimum value of 571 Nm ³ / h, the memorial amount given corresponding to the detected value of the boiler evaporation amount indicates the gradual decrease line of (b) in FIG. It is 857 Nm ³ / h when it is a straight line. If the “PID tracking amount for maintaining the normal pressure of 1.27 MPa” is 940 Nm ³ / h, the smallest value is 857, so the fuel flow rate is such that the tracking amount is 857 Nm ³ / h. The opening degree of the control valve is adjusted. This selection of the minimum value can be easily grasped from FIG.

Such inhibition add焚量selection, because is reduced from the state where it has been reheating at 940 nm ³ / h to 857 nm ³ / h, the boiler inlet exhaust gas temperature is lowered from 870 ° C., boiler evaporation amount 26.9T / There is no doubt that it will drop from h. Because 857 nm ³ / h is less than 920 nm ³ / h of number 8, a calculated boiler inlet exhaust gas temperature is lowered from 850 ° C., should the boiler evaporation amount drops below 26.0t / h. Therefore, the boiler can escape from the overload by the suppressed amount of chasing. Assuming that the minimum value is 920 Nm ³ / h obtained in the (1-1) step, the boiler inlet exhaust gas temperature should be 850 ° C. and the boiler evaporation amount should be 26.0 t / h. It can be understood from the fact. Therefore, in principle, the amount of restraint must be controlled once after overload, and it is not necessary to repeat until it settles down. It turns out that it becomes very simple control.

Since the amount of restraint tracking given by (a) and (b) of FIG. 11 is kept from the maximum to the minimum value of the group of tracking amounts obtained in the (1-1) step, The minimum combustion amount, which is the minimum amount of fuel that can be operated by the boiler as described in, is not reduced at once. By the way, if the minimum combustion amount is 450 Nm ³ / h in this example, 857 Nm ³ / h is much larger than that, and the amount of remedy does not drop sharply, even if the amount of evaporation varies. Since the amount of evaporation is not so short that the demand on the steam demand side cannot be met, the operation on the steam demand side is not disrupted.

  As mentioned above, FIG. 8 shows the case of Form A, and FIG. In FIG. 8, since it is not in an overload state, even if the temperature signal from the sensor 22 or the evaporation amount signal from the sensor 25 enters the boiler overload take-off operation application necessity determination unit 35, it is applied as a signal that does not correspond to an overload. The necessity determination unit 35 does not issue a transition trigger, and each contact point of the information transmission change unit 36 does not allow signal transmission to the output value determination unit 32. A vapor pressure signal is supplied from the sensor 23 to the PID control unit 29, and a PID tracking amount based on this signal is calculated, and this is the fuel amount adjustment command unit via the fifth conduction contact from the top. 30, the opening degree of the fuel flow control valve 16 is determined, and the exhaust gas is heated by the remedy burner 15. Needless to say, the actual tracking amount is detected by the fuel flow meter 17 and the like, and feedback is applied based on the detected amount to separately control the tracking accuracy. Incidentally, transmission is performed where the transmission line in FIG. 8 is represented by a solid line, and there is no transmission where the transmission line is represented by a broken line. Therefore, it can be seen that the output value determination unit 32 is not functioning.

  FIG. 9 shows a break-away operation from an overloaded state. The overtemperature signal 870 ° C. from the sensor 22 and the excessive evaporation signal 26.9 t / h from the sensor 25 are applied to the boiler overload breakaway operation. Upon entering the necessity determination unit 35, the application necessity determination unit 35 issues a transition trigger on the assumption that they are signals corresponding to an overload, and conducts the four contacts on the information transmission change unit 36, thereby causing an excessive signal. Is allowed to be transmitted to the output value determination unit 32. The PID tracking amount calculated based on the vapor pressure signal supplied from the sensor 23 to the PID control unit 29 is based on the following three tracking amounts, that is, detection signals from the sensors 12 and 13. The “predicted tracking amount when no fresh air is supplied” obtained in the step (1-1) read from the “tracking amount reading unit corresponding to intake air temperature / load” 43, and the detection signal from the sensor 22 are also included. In addition, the “over-temperature range suppression tracking amount” obtained in the (2-1) process from the “temperature vs. tracking amount chart generation unit during overload” 44 to the “temperature overload escape tracking calculation unit” 45 Based on the detection signal from the sensor 25, the “evaporation amount vs tracking amount chart generation unit at overload” 46 is followed by the “evaporation amount overload escape tracking amount calculation unit” 47 (2-3). Along with the “excessive evaporation amount area suppression tracking amount” required in the process, the minimum tracking amount selection unit 4 It is delivered to. Therefore, the tracking amount selected as the minimum is supplied to the fuel amount adjustment command unit 30, but the route through which the PID tracking amount is directly supplied is blocked by the open contact at the bottom of the information transmission changing unit 36. Therefore, the amount of remembrances entering the command unit 30 does not overlap. Note that the transmission line in FIG. 9 is represented by a solid line when information is transmitted, and the broken line is represented by no transmission. Therefore, it can be seen that the output value determination unit 32 is in an active state. Incidentally, if the boiler inlet exhaust gas temperature falls below 850 ° C. and the boiler evaporation amount falls below 26.0 t / h, the transition trigger that has been issued from the boiler overload escape operation necessity determination unit 35 to the information transmission change unit 36 disappears. Then, the contact state is automatically returned as shown in FIG. 9 (form B) to FIG. 8 (form A), and only the PID tracking amount based on the steam drum pressure is calculated, and control is performed so as to maintain the normal pressure. Is done.

When this step (3-3) is adopted, for example, the detected value of the boiler inlet exhaust gas temperature exceeds the maximum allowable boiler operation temperature of 850 ° C., but the detected value of the boiler evaporation amount is not supplied with fresh air. When the amount of evaporation that can be achieved at the time does not exceed 26.0 t / h, the amount of remedy corresponding to the “excess amount of evaporation suppression suppression amount” obtained in the step (2-3) is shown in FIG. 1,287 Nm ³ / h before getting on the gradual decrease line. Therefore, as can be seen from the above explanation, this 1,287 Nm ³ / h cannot be selected as a minimum value larger than the others. On the other hand, the detected value of the boiler inlet exhaust gas temperature does not exceed the maximum allowable boiler operation temperature of 850 ° C., but the detected value of the boiler evaporation amount exceeds the achievable evaporation amount of 26.0 t / h without fresh air supply. The memorization amount corresponding to the “excessive temperature range restraining memorial amount” obtained in the (2-1) step is assigned 1,287 Nm ³ / h before getting on the gradual decrease line from (a) of FIG. Therefore, as can be seen from the above description, this 1,287 Nm ³ / h cannot be selected as the minimum value.

In the above, the case where the motor intake air temperature is 15 ° C. and the load is 75% has been described as an example, but when the motor intake air temperature is 30 ° C. and the load is 96%, for example, the number is replaced with the number 8 in Table 1 of FIG. 12 and 920 Nm ³ / h determined in the (1-1) step is replaced with 676 Nm ³ / h. However, the maximum value of 1,287 Nm ³ / h and the minimum value of 571 Nm ³ / h in the “estimated tracking amount when no fresh air is supplied” are used as they are, and the suppression and tracking of (a) and (b) of FIG. No change is made to the calculation of the weight.

By the way, although the (3-3) process has been described as an example in the third process, a case where the (3-1) process is adopted will be briefly introduced.
The step (3-1) has been described above.
"Estimated amount of remembrance when no fresh air is supplied" determined in step (1-1)
“Excessive temperature range restraint memorial amount” obtained in step (2-1)
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. This means that the “excessive evaporation range suppression memorial amount” obtained in step (2-3) of the steps described in step (3-3).
Is not considered. In this case, it is understood that the (2-3) step is not necessary.

The case where the step (3-2) is adopted is as follows. The step (3-2) is as described above.
"Estimated amount of remembrance when no fresh air is supplied" determined in step (1-1)
“Excess evaporation amount area suppression memorial amount” obtained in the second (2-3) step
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. This means that the “excessive temperature range restraint memorial amount” obtained in step (2-1) of the steps described in step (3-3).
Is not considered. In this case, it is understood that the (2-1) step is not necessary.

  The above three steps are listed in Case 3, Case 1, and Case 2 of Table 5 “Combination of inclusion steps in Form A & B” in FIG. In this way, in the control system, which one of the (3-1) process to the (3-3) process should be adopted can be determined individually in the cogeneration facility. It can be seen that the process is not always prepared. Even if the exhaust gas temperature sensor 22 (see FIG. 7) and the steam flow meter 25 are accurate, they are placed in a measurement environment with special phenomena such as furnace wall radiation. It can be unreliable. In the case of the (3-3) process, the reliability of the system can be secured more easily than the (3-1) process and the (3-2) process in that it is monitored by two different overload factors. Needless to say.

  In this “Blower Continuous Stop” mode, the operation of expanding the evaporation cannot be performed because the blower is not operated. However, even if an overload factor of the boiler occurs, the suppression memorization is intended to escape from the overload. The amount is limited to the range of boiler protection operation in consideration of the prime mover intake air temperature and load of the power generator. In other words, overheating factors such as overheating of boiler heat transfer tubes and excessive evaporation are dealt with with the minimum amount of remedy based on those factors, and the boiler operation minimum remedy amount is not dropped at once. In addition, the operation on the steam demand side will not cause confusion due to rapid fluctuations.

  This is the end of the description of the forms A & B. Next, the forms F & G in the “blower continuous operation” mode will be described. Form G, which is an overload operation when there is fresh air supply, includes steps (1-2), (2-2) and / or (2-4) as shown in Table 4 of FIG. Necessary, and at least one of the (3-4) step, the (3-5) step, and the (3-6) step is required. Form F is a non-overload operation when fresh air is supplied, and the (3-4) step, (3-5) step, and (3-6) step are not required. ) Step, (2-2) step, and (2-4) step are not required, but in the sense to prepare for the operation of form G, that is, any step that is indispensable for the “always blower operation” mode. It has become. By the way, the form F & G in Table 4 is the same as the latter half of the latter, as can be seen from comparison with forms C, D, and E described later. It can be seen that the “blower continuous operation” mode is inevitably possible if the “blower operation stop automatic switching” mode is prepared.

  In the power generation device, the amount of tracking and the amount of boiler evaporation achieved thereby differ depending on which is the prime mover intake air temperature or the load. The step (1-2) includes “estimated amount of exhaust when there is fresh air supply” and “estimated amount of fresh air supply”, which are the estimated exhaust amount of exhaust when there is fresh air supply for each engine intake air temperature and power generation load, The boiler evaporation amount at this time is calculated as “amount of evaporation achievable when fresh air is supplied”. More specifically, the mixed gas in a state where fresh air is mixed with exhaust gas generated according to several typical prime mover intake air temperatures during operation of the prime mover and several typical loads at that time. Is a range that does not exceed the maximum allowable boiler operation temperature at the inlet of the exhaust heat boiler, for example, 850 ° C., and the set pressure unique to the exhaust heat boiler, for example, 1.27 MPa. The “estimated follow-up amount when there is a supply” and the “estimated amount of fresh air supply” and the “evaporation amount achievable when there is fresh air supply” achieved at this time are calculated.

  An example is shown in Table 2 of FIG. Similar to the case of Table 1, this is obtained by heat calculation such as heat exchange and heat loss, and is considered to be plausible by being corrected and supplemented by data collected during trial operation. The data calculated in this way is stored in the data storage unit 28 of the tracking amount calculation control means 26 from the system data input unit 27 of FIG. The data that should be input in this data are the intake air temperature, the load factor, the calculated expected amount of tracking, the estimated amount of fresh air supply, the boiler inlet exhaust gas temperature, and the achievable evaporation amount. The motor exhaust gas amount and the motor exhaust gas temperature are provided by the design group of the power generator, and the exhaust gas that has been traced in consideration of these and heat loss in the gas distribution system is the maximum allowable boiler operation temperature 850 There is a need for an expected amount of tracking that can be kept up to 0 ° C. and can maintain the normal pressure of the exhaust heat boiler 1.27 MPa. The amount of dilution air required based on this is the “estimated amount of fresh air supply”, and the amount of evaporation generated according to these is calculated as “amount of evaporation achievable when fresh air is supplied”. Note that, for example, the amount of compensation for the intake air temperature obtained using the power generation load as a parameter is also stored in the form shown in FIG. 10B, and the amount of compensation for any intake air temperature or power generation load is included in each line. It is given as an insertion point or extrapolation point.

In the (2-2) step, a chart for calculating the “excessive temperature range restraint memorizing amount” as the restraint memorizing amount in the zone exceeding the “maximum allowable boiler operation temperature of 850 ° C.” when there is fresh air supply, -2) Generate automatically based on the data obtained in the process. More specifically, when a fresh air is supplied and a regenerative operation is performed, the detected value of the exhaust gas temperature at the boiler inlet is, for example, 50 “excess allowable temperature” that is predetermined from the maximum allowable boiler operation temperature of 850 ° C. “Excessive maximum temperature” with an additional ℃. In case of any temperature in the zone up to 900 ℃, as the amount of remedy until the boiler operation allowable maximum temperature is detected. As the maximum value of 1,587 Nm ³ / h of the number 19 in Table 2 of FIG. 4 as the maximum value, and as the amount of remedy when the excess maximum temperature is detected, the amount of remedy when there is fresh air supply As the minimum value, the memory amount of 1,197 Nm ³ / h of No. 11 in the table is satisfied, and the amount of memory when the intermediate temperature is detected continuously decreases from the maximum value to the minimum value. To a series of values that maintain the relationship Takes to create a chart so devote corresponding values of the intermediate. This is stored in the form shown in FIG. 14 (a), and is arbitrarily given by an interpolation point on each line. The series of values may be on a straight line, but may be applied on a gradually decreasing line other than the straight line. Incidentally, among the data obtained in the (1-2) step, the above-mentioned maximum and minimum values and the values between them are used to determine the amount of suppression and tracking within the operating conditions conceivable for the power generator. This is because the exhaust heat boiler is operated within the range, and the heat balance between the power generation device and the exhaust heat boiler is easily maintained, and it is possible to keep the generated evaporation from drastically decreasing. This is based on knowledge and is the same as in the case of the (2-1) step.

In the second (2-4) step, a chart for calculating the “excess evaporation amount region suppression tracking amount” calculation chart as the suppression tracking amount in the band exceeding the “evaporation amount 30.3 t / h achievable when fresh air is supplied” (1-2) Automatically generated based on the data obtained in the process. More specifically, when the fresh air is supplied and the regenerative operation is performed, the detected value of the boiler evaporation amount is calculated according to the prime mover intake air temperature, for example, 15 ° C. and the load 75%. “Excessive maximum evaporation amount with fresh air supply” obtained by adding, for example, 1.5 t / h of a predetermined “excess allowable evaporation amount” to the evaporation amount, for example, from 30.3 t / h that can be achieved at any time In preparation for when the amount of evaporation in any of the bands up to 8 t / h, the expected amount of tracking when there is a fresh air supply as a tracking amount until the amount of evaporation that can be achieved with the supply of fresh air 30.3 t / h is detected The maximum value of 1,587 Nm ³ / h is applied in the amount, and the minimum value of 1,197 Nm ³ / h in the expected amount of fresh air supply when the excess maximum evaporation amount is detected As a memorial amount when an intermediate evaporation amount is detected, To create a chart so devote corresponding values of the intermediate in a series of values maintaining the relationship that continuously decreases from a large value to a minimum value. This is stored in the form shown in (b) of FIG. 14, and is arbitrarily given by an interpolation point on each line. In this case as well, the series of values is not limited to those on a straight line, but may be those on a gradually decreasing line other than a straight line.

The (3-4) step and the (3-5) step will be described later and the (3-6) step will be described later. In this process, of the overload suppression memorial amount when there is fresh air supply,
"Estimated amount of remedy when fresh air is supplied" calculated in step (1-2)
“Excessive temperature range restraint memorial amount” obtained in step (2-2)
“Excess evaporation amount area suppression memorial amount” obtained in the second (2-4) step
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. Specifically, when the exhaust gas supplied from the prime mover is being operated to mix fresh air and increase the amount of exhaust, that is, when the exhaust gas is being exhausted, the fresh air is mixed to detect boiler steam. Achievable when the detected value of the boiler exhaust gas temperature exceeds the maximum allowable boiler operating temperature of 850 ° C and the detected value of the boiler evaporation amount is supplied with fresh air when operating with the PID tracking amount based on pressure When the amount of evaporation exceeds 30.3 t / h, among the expected amount of tracking with fresh air supplied, the amount of tracking corresponding to the detected intake air temperature and load at that time, and the expected amount of tracking with fresh air supplied When there is a renewal amount and a fresh air supply given in accordance with the detected value of the boiler inlet exhaust gas temperature among a series of values from the maximum value of 1,587 Nm ³ / h to the minimum value of 1,197 Nm ³ / h 1,587Nm ³ described above the maximum value in the predicted add焚量A series of add焚量provided in correspondence with the detected value of the boiler evaporation amount of the values, PID control are always performed by the vapor pressure based on from h to 1,197Nm ³ / h was above the minimum value While the opening of the fuel flow control valve of the tracking burner that raises the temperature of the exhaust gas from the prime mover is adjusted so as to be the smallest amount of PID tracking by The amount of discharge from the blower that sends fresh air to the upstream side of the combustor burner is adjusted to adjust the opening of the fresh air supply control valve so that the fresh air supply amount corresponds to the detected intake air temperature and load value of the prime mover. It is adjusted by changing the air volume by inverter control of the blower motor.

Next, it will be specifically described. Assume that the motor intake air temperature is 15 ° C. and the load is 75%. At this time, “the amount of remedy corresponding to the detected value of the intake air temperature and load of the prime mover at that time among the expected amount of remedy when fresh air is supplied” is 1,289 Nm ³ / h shown in number 8 of Table 2. . This can also be read from FIG. 10 (b). Assuming that the detected value of the boiler inlet exhaust gas temperature is 880 ° C., which exceeds the maximum allowable boiler operation temperature of 850 ° C., “the minimum value 1 from the maximum value 1,587 Nm ³ / h in the expected amount of tracking with fresh air supply” , 197 Nm ³ / h among the series of values up to 197 Nm ³ / h, the amount of compensation given corresponding to the detected value of the boiler inlet exhaust gas temperature is 1,353 Nm ³ / h. Next, assuming that the detected value of the boiler evaporation amount is 31.5 t / h, which exceeds the achievable evaporation amount of 30.3 t / h when fresh air is supplied, “the maximum of the expected amount of tracking when fresh air is supplied” The memorial amount given corresponding to the detected value of the boiler evaporation amount among a series of values from the value 1,587 Nm ³ / h to the minimum value 1,197 Nm ³ / h ”is a gradual decrease line in FIG. Is a straight line of 1,275 Nm ³ / h. If the “PID tracking amount for maintaining the normal pressure 1.27 MPa” is 1,306 Nm ³ / h, the smallest value is 1,275, so the tracking amount is 1,275 Nm ³ / h. The opening of the fuel flow control valve is adjusted so that In addition, the expected fresh air supply amount corresponding to the detected value of the intake air temperature of 15 ° C. and the load of 75% is read as 16,300 Nm ³ / h in No. 8 of Table 2, and fresh air is sent upstream of the memorial burner. Is adjusted at a frequency of 35 Hz by adjusting the opening of the fresh air supply amount control valve or by controlling the inverter of the blower motor. The state of selection of the minimum value can be easily grasped from FIG.

By the way, the inverter control changes the frequency of the electric power supplied to the motor and changes the air volume by setting the rotational speed of the blower to a desired value, but in the case of numbers 1 to 5 as listed in Table 2 For example, 25 Hz. The fresh air supply amount at this frequency is 13,600 Nm ³ / h. In the case of No. 6 to No. 10, the frequency is 35 Hz, and the fresh air supply amount in this frequency is 16,300 Nm ³ / h, and in the case of No. 11 to No. 15, it is 45 Hz. The amount is 21,400 Nm ³ / h, the number 16 to the number 19 is 60 Hz, and the fresh air supply amount at this frequency is 25,200 Nm ³ / h. In this example, the commercial power supply frequency is given on the basis of 60 Hz. Needless to say, the last 25,200 Nm ³ / h is the amount of air blown when the frequency is 100%. In addition, although it is displayed as 60 Hz at the time of the boiler independent operation | movement next to the number 19, this is a motor drive frequency employ | adopted by the driving | operation of the form H mentioned later. By the way, 60 Hz in the Kansai area has been described as a reference. However, in the area where the commercial power supply frequency is 50 Hz, the air volume achieved at 20, 30, 40 Hz, etc. may be assigned.

The selection of the inhibition add焚量of as described above, since it is not reduced to 1,275Nm ³ / h from the reheating condition of 13A natural gas 1,306Nm ³ / h, the boiler inlet exhaust gas temperature is lowered from 880 ° C. There is no doubt that the amount of boiler evaporation decreases from 31.5 t / h. Since 1,275Nm ³ / h is less than 1,289Nm ³ / h of number 8, a calculated boiler inlet exhaust gas temperature is lowered from 850 ° C., should the boiler evaporation amount drops below 30.3t / h. Therefore, the boiler can escape from the overload by the suppressed amount of chasing. Assuming that the minimum value is 1,289 Nm ³ / h obtained in the (1-2) step, the boiler inlet exhaust gas temperature should be 850 ° C. and the boiler evaporation amount should be 30.3 t / h. That's why it can be understood. In principle, the control of the amount of remedy does not need to be repeated once after overload until it settles down, so the control itself is simplified. That is, malfunctions and time lags are reduced as much as possible compared to operations such as a step-by-step tracking amount reduction operation and feedback control.

As can be seen from this, the amount of restraint tracking given by (a) and (b) of FIG. 14 can be kept from the maximum to the minimum of the group of tracking amounts obtained in the (1-2) step. The minimum combustion amount, which is the minimum amount of boiler operation as described in the background art section, is not dropped at a stretch. By the way, if the minimum combustion amount is 850 Nm ³ / h in this example, 1,275 Nm ³ / h is very large, the tracking amount does not drop rapidly, and even if the evaporation amount fluctuates, the steam demand side Therefore, the amount of evaporation that cannot be fulfilled rapidly cannot be reduced, and the operation on the steam demand side is not confused.

Details of the upper half of FIG. 1 for executing this form F & G are shown in FIGS. FIG. 16 shows form F, and FIG. In FIG. 16, since it is not in an overload state, even if the temperature signal from the sensor 22 or the evaporation amount signal from the sensor 25 enters the boiler overload take-off operation application necessity determination unit 35, it is applied as a signal that does not correspond to an overload. The necessity determination unit 35 does not issue a transition trigger, and each contact point of the information transmission change unit 36 does not allow signal transmission to the output value determination unit 32. A vapor pressure signal is supplied from the sensor 23 to the PID control unit 29, and a PID tracking amount based on this signal is calculated, and this is the fuel amount adjustment command unit via the fifth conduction contact from the top. 30, the opening degree of the fuel flow control valve 16 is determined, and the exhaust gas is heated by the remedy burner 15. It should be noted that transmission is performed where the transmission line is represented by a solid line, transmission is not performed where the transmission line is represented by a broken line, and it can be seen that the output value determining unit 32 is not functioning except for the fresh air supply amount reading unit 38. . At this time, a read trigger from a limit switch L / S of a mode selection switch 51 (to be described later) is set so that the supplied fresh air has an expected fresh air supply amount corresponding to the detected intake temperature and load value of the prime mover at that time. In response, the fresh air supply amount reading unit 38 reads the fresh air supply amount from the data storage unit 28. If this is input to the fresh air supply command unit 41, the discharge amount of the blower that sends fresh air to the upstream side of the combustor burner is used to adjust the opening of the fresh air supply control valve (not shown in FIG. 16), or It is adjusted by inverter control of the blower motor 20. For example, as described above, since the operation is performed at the motor intake air temperature of 15 ° C. and the load of 75%, in the case of inverter control, the motor is driven and supplied at the above-described 35 Hz described in number 8 in Table 2. The amount of energy is 16,300 Nm ³ / h.

  FIG. 19 shows an operation mode in an overload state. The overtemperature signal from the sensor 22 is 880 ° C. and the overevaporation signal from the sensor 25 is 31.5 t / h. Upon entering the determination unit 35, the application necessity determination unit 35 issues a transition trigger to make the four contacts on the information transmission change unit 36 conductive by assuming that the signal corresponds to an overload, and an output value determination unit for an excessive signal 32 is allowed to be transmitted. The PID tracking amount calculated based on the vapor pressure signal supplied from the sensor 23 to the PID control unit 29 is based on the following three tracking amounts, that is, based on detection signals from the sensors 12 and 13. Based on the detection signal from the sensor 22 and the “estimated tracking amount when fresh air is supplied” obtained in the step (1-2) read from the tracking amount reading unit 43 corresponding to the intake air temperature / load. “Excessive temperature range suppression tracking amount” obtained in step (2-2) from “temperature overload tracking amount chart generation unit” 44 to “temperature overload escape tracking amount calculation unit” 45 The (2-4) step of following the “evaporation amount overload escape tracking amount calculation unit” 47 from the “evaporation amount vs tracking amount chart generation unit during overload” 46 based on the detection signal from the sensor 25 Together with the “excessive evaporation range suppression tracking amount” obtained in step 4, to the minimum tracking amount selection unit 40 It is. Incidentally, in order to extract the achievable evaporation amount according to the prime mover intake air temperature and the load, the prime mover intake air temperature and the load at that time from the sensors 12 and 13 are transferred to the “evaporation amount vs overload amount chart generation unit at overload” 46. Has been introduced. The tracking amount selected as the minimum in the minimum tracking amount selection unit 40 is supplied to the fuel amount adjustment command unit 30, but the route through which the PID tracking amount is directly supplied is the lowermost part of the information transmission change unit 36. Therefore, the amount of remedies entering the command unit 30 does not overlap. In FIG. 19, transmission is performed where the transmission line is represented by a solid line, and transmission is performed where the transmission line is represented by a broken line, which is the same as in FIG. Therefore, it can be seen that the output value determination unit 32 is in an active state. Incidentally, when the boiler inlet exhaust gas temperature falls below 850 ° C. and the boiler evaporation amount falls below 30.3 t / h, the transition trigger that has been issued from the boiler overload escape operation necessity determination unit 35 to the information transmission change unit 36 disappears. Then, the contact conduction state is automatically returned as shown in FIG. 19 (form G) to FIG. 16 (form F), and only the PID tracking amount based on the steam drum pressure is calculated, and control is performed so as to maintain the normal pressure. Is done.

When the step (3-6) is adopted, for example, the detected value of the boiler inlet exhaust gas temperature exceeds the maximum allowable boiler operation temperature of 850 ° C., but the detected value of the boiler evaporation amount is when fresh air is supplied. When the achievable evaporation amount does not exceed 30.3 t / h, the amount of remedy corresponding to the “excess evaporation amount region suppression remedy amount” obtained in the step (2-4) is shown in FIG. 1,587 Nm ³ / h before getting on the gradual decrease line. Therefore, as can be seen from the above description, this 1,587 Nm ³ / h cannot be selected as the minimum value. On the other hand, the detected value of the boiler inlet exhaust gas temperature does not exceed the maximum allowable boiler operation temperature of 850 ° C., but the detected value of the boiler evaporation amount exceeds the achievable evaporation amount of 30.3 t / h when no fresh air is supplied. In this case, the amount of memorization corresponding to the “excessive temperature range restraint memorizing amount” obtained in the step (2-2) is 1,587 Nm ³ / h before getting on the gradual decrease line from (a) of FIG. It is done. Therefore, as can be seen from the above description, this 1,587 Nm ³ / h cannot be selected as the minimum value.

In the above, the case where the motor intake air temperature is 15 ° C. and the load is 75% has been described as an example. However, when the motor intake air temperature is, for example, 0 ° C. and the load is 50%, it corresponds to the number 4 instead of the number 8 in Table 2. Then, 1,289 Nm ³ / h obtained in the (1-2) step is replaced with 1,438 Nm ³ / h. However, the maximum value of 1,587 Nm ³ / h and the minimum value of 1,197 Nm ³ / h in the “estimated tracking amount when fresh air is supplied” are used as they are, and are shown in FIGS. 14 (a) and 14 (b). No change is made in the calculation of the suppression memorial amount.

By the way, although the (3-6) step has been described as an example in the third step, the case where the (3-4) step is adopted will be briefly introduced.
The step (3-4) has been described above.
"Estimated amount of remedy when fresh air is supplied" calculated in step (1-2)
“Excessive temperature range restraint memorial amount” obtained in step (2-2)
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. In addition, the discharge rate of the blower that sends fresh air to the upstream side of the combustor burner is set so that the fresh air supply amount corresponding to the detected intake air temperature and load of the prime mover at that time is among the expected fresh air supply amount. Also adjust. This means that “excessive evaporation range suppression memorization amount” obtained in step (2-4) of step (3-6).
Is not considered. In this case, it is understood that the (2-4) step is not necessary.

The case of adopting the (3-5) step is as follows. The step (3-5) has been described above.
"Estimated amount of remedy when fresh air is supplied" calculated in step (1-2)
“Excess evaporation amount area suppression memorial amount” obtained in the second (2-4) step
“PID memory amount” calculated by PID control based on vapor pressure
The minimum value is selected and the valve opening adjustment command for the corresponding fuel flow rate control valve is issued. In addition, the discharge rate of the blower that sends fresh air to the upstream side of the combustor burner is set so that the fresh air supply amount corresponding to the detected intake air temperature and load of the prime mover at that time is among the expected fresh air supply amount. Also adjust. This means that the “excessive temperature range restraint memorial amount” obtained in step (2-2) in step (3-6).
Is not considered. In this case, it is understood that the (2-2) step is not necessary.

  The above three steps are listed in Case 6, Case 4, and Case 5 of Table 6 “Combination of inclusion steps in form F & G” in FIG. From this point of view, it is only necessary to individually determine which of the (3-4) to (3-6) steps is adopted in the control system in the cogeneration facility. It can be seen that the process is not always prepared. Even if the exhaust gas temperature sensor 22 (see FIGS. 16 and 19) and the steam flow meter 25 have high accuracy, the measurement is performed as a result of being placed in a measurement environment having a special phenomenon such as furnace wall radiation. It can be unreliable. Therefore, in the case of the (3-6) step, the reliability and certainty of the system are improved compared to the (3-4) step and the (3-5) step in that monitoring is performed by two different overload factors. It can be said that it becomes easy.

  Next, a process when the “power generation device is in operation” and the “blower operation stop automatic switching” mode is set will be described. Although it touched for a while also in Table 4, it corresponds with the "blower always operation" mode in the first half process, but the process of (4) is added. Since (4) has already been described, the reprint here is omitted. By the way, when there is a request for an excessive amount of evaporation that exceeds the schedule on the steam demand side at the time of cogeneration system planning, the fan is operated in the same manner as in the above-mentioned “blower continuous operation” mode, and the input energy is reduced. Increasing the number can meet that demand. When obtaining the amount of evaporation at or near the time of planning in the form A described above, when trying to shift from the form A to the overload release operation of the form B, the form B is not taken but the form F is taken. It can be understood from the explanations so far that it is possible to meet the demand for an excessive amount of evaporation exceeding the schedule by switching. It can be met by switching from form C to form D.

  Since the switching to the form D is triggered by the occurrence of overload, the switching conditions satisfying the generation operation of the excess capacity evaporation amount and the overheating of the boiler heat transfer tube described above, that is, the “evaporation amount expansion requirement” It corresponds to. In addition to these, reduction of vapor pressure and occurrence of abnormal values of the PID tracking amount can also be used to determine whether switching is necessary. Therefore, when all or one of the four “evaporation amount expansion requirements” is satisfied, the mode is switched to the form D as “switching condition”, so that the excessive demand on the steam demand side can be met. . The fan is operated in the form D and the form E in the same manner as described in the form F & G, but only after the “evaporation amount expansion requirement” is satisfied. On the other hand, “when the switching condition is no longer met”, that is, “when the evaporation amount expansion requirement is no longer met” means that all or any of the four “evaporation amount expansion requirements” described above is canceled. The air blower is stopped because there is no excessive demand on the demand side, and an attempt is made to return to form C. It is the “blower operation automatic switching” mode that attempts to perform this switching or reverse switching (switching cancellation).

  The details of the four types of “evaporation amount expansion requirements” will be described individually below. However, since the control system can be fully or partially controlled, it is possible to perform automatic operation stop switching. It is sufficient to have one process. As shown in Table 7 of FIG. 18, they are the (4-1) step, the (4-2) step, the (4-3) step, and the (4-4) step. However, since the exhaust gas temperature sensor, the steam flow meter, and the drum pressure sensor are also placed in an environment where special phenomena can occur, two or more “evaporation expansion requirements” are monitored. It is preferable to do so. In the following, the examples are based on the assumption that the motor intake air temperature is 15 ° C. and the load is 75%.

  In the (4-1) step, when the exhaust gas replenishment amount is determined by PID calculation without mixing fresh air when exhaust gas supplied from the prime mover is mixed, that is, during exhaust gas exhaustion. When the PID calculation is performed based on the steam pressure of the boiler without mixing fresh air and the amount of remedy is determined to keep the steam pressure at the set pressure, the detected value of the boiler inlet exhaust gas temperature is When the maximum allowable boiler operation temperature is 850 ° C. or higher, fresh air is mixed with the exhaust gas supplied from the prime mover from that point, and the PID calculation is continuously performed to determine the amount of remedy. That is, PID calculation is performed based on the subsequent steam pressure of the boiler, and the PID tracking amount is increased in order to keep the steam pressure at the set pressure. On the other hand, when the detected value of the boiler inlet exhaust gas temperature becomes equal to or lower than the boiler inlet exhaust gas temperature of 806 ° C. corresponding to the detected value of the prime mover intake air temperature of 15 ° C. and the load of 75%, fresh air is introduced into the exhaust gas from that point. While mixing is stopped, the amount of exhaust gas is continuously determined by PID calculation. That is, PID calculation is performed based on the subsequent steam pressure of the boiler to reduce the amount of remembrance.

  In the (4-2) step, when the exhaust gas replenishment amount is PID-calculated without mixing fresh air when exhaust gas supplied from the prime mover is detected, the detected value of the boiler evaporation amount is When the amount of evaporation that can be achieved without supply of fresh air, for example, 26.0 t / h, calculated according to the engine intake air temperature of 15 ° C. and 75% of the load is supplied, fresh air is supplied from that point. Based on the steam pressure, the PID calculation is continued to determine the amount of remembrance. On the other hand, when the detected value of the boiler evaporation amount becomes 26.0 t / h or less, which is achievable when no fresh air is supplied, the mixing of fresh air with the exhaust gas is stopped and the subsequent vapor pressure is reduced. Based on the PID calculation, the memorial amount is determined.

  In the step (4-3), the detected value of the boiler steam pressure is equal to or lower than the set pressure when the exhaust gas replenishment amount is PID-calculated without mixing fresh air when the exhaust gas supplied from the prime mover is replenished. At that time, fresh air is supplied to the exhaust gas from that point, and the PID calculation is continuously performed based on the subsequent vapor pressure to determine the amount of remedy. On the other hand, when the detected value of the boiler vapor pressure becomes equal to or higher than the set pressure, mixing of fresh air with the exhaust gas is stopped from that point, and the amount of renewal is determined by PID calculation based on the subsequent vapor pressure.

In the step (4-4), when the exhaust gas replenishment amount is PID-calculated without mixing fresh air when the exhaust gas supplied from the prime mover is mixed, the PID replenishment amount is not supplied with fresh air. When the remedy amount 920 Nm ³ / h or more corresponding to the detected value of the intake air temperature 15 ° C. and the load 75% of the prime mover at that time in the expected amount of remedy at that time, the exhaust gas supplied from the prime mover is newly While supplying air, PID calculation is continued based on the subsequent vapor pressure to determine the amount of remembrance. On the other hand, when the PID tracking amount falls below 920 Nm ³ / h corresponding to the detected value of the motor intake air temperature 15 ° C. and the load 75% of the expected tracking amount when there is no fresh air supply Then, the mixing of fresh air with the exhaust gas is stopped from that time, and the amount of remedy is determined by PID calculation based on the subsequent vapor pressure.

  Nevertheless, it is preferable to prevent chattering in order to prepare for fluctuations in the “evaporation amount expansion requirement” near the operation mode switching condition and to ensure stable control at that time. In the (4-1) step, from the form C to the form D, the detected value of the boiler inlet exhaust gas temperature becomes equal to or higher than the “new air supply start temperature” which is higher than the boiler operation allowable maximum temperature by a predetermined amount. As the switching condition, the detected value of the exhaust gas temperature at the boiler inlet is from the intake air temperature of the prime mover at that time, for example, 15 ° C. and the detected value of the load, for example, 75%, from the boiler inlet exhaust gas temperature 806 ° C. (see number 8 in Table 2). It is set as a reverse condition from form D to form C that the temperature is equal to or lower than the “fresh air supply stop temperature” that is lower than a predetermined amount.

  In the (4-2) step, the detected value of the boiler evaporation amount is an achievable evaporation amount when no fresh air is supplied, which is calculated according to the prime mover intake air temperature of 15 ° C. and the load of 75%, for example, 26.0 t. It is possible to achieve the boiler evaporation detection value when there is no fresh air supply, with the condition for switching from form C to form D being equal to or greater than the “fresh air supply start evaporation amount” that exceeds a predetermined amount from / h The condition for reversing from form D to form C is that the amount of evaporation exceeds 26.0 t / h by a predetermined amount, but is less than or equal to the “fresh air supply stop evaporation amount” smaller than the fresh air supply start evaporation amount described above. Set as.

  In the (4-3) step, the switching condition from the form C to the form D is that the detected value of the boiler steam pressure is equal to or lower than the “fresh air supply start steam pressure” which is lower than the set pressure by a predetermined amount. To do. On the other hand, it is set as a reverse condition from form D to form C that the detected value of the boiler steam pressure is equal to or higher than the “fresh air supply stop steam pressure” that exceeds the set pressure by a predetermined amount.

In the step (4-4), the amount of tracking 920 Nm corresponding to the detected value of the motor intake air temperature 15 ° C. and the load 75% of the estimated amount of tracking when the fresh air supply is not present in the (4-4) step. The switching condition from form C to form D is equal to or greater than the “fresh air supply start tracking amount” that is lower than ³ / h by a predetermined amount, and the PID tracking amount is the expected additional tracking when there is no fresh air supply. Of the dredging amount, it is lower than the amount of remedy 920 Nm ³ / h corresponding to the detected value of the intake air temperature 15 ° C. and the load 75% of the prime mover at that time, but it is less than the amount of fresh air supply starting remedy described above. Is set as a reverse condition from the form D to the form C to be less than the “fresh air supply stop tracking amount”.

  FIG. 20 shows form C, which is a case where fresh air is not supplied and overload operation is not being performed, but any of the operation form switching conditions prompts switching from form C to form D described below. Not. Therefore, it is substantially the same as Form A. However, in the system data input unit 27, “expected evaporation amount / replacement amount data during operation of the power generator” corresponds only to the form A & B in that not only the data in Table 1 in FIG. 3 but also the data in Table 2 in FIG. 4 are added. This is different from FIG.

FIG. 21 shows a form D, which is switched from the form C of FIG. 20 and turns on the blower and enters the “evaporation expansion operation”. FIG. 22 is a form E in the case of entering a break-away operation due to an overload operation in the state of the form D. In order to be able to switch from form C to form D, the fresh air supply necessity judgment unit 34 shown in FIG. 20 receives data from the data storage unit 28, and when it is judged “necessary”, a read trigger (FIG. 21) is sent to the fresh air supply amount reading unit 38 to enable the air flow rate of 16,300 Nm ³ / h described in the “blower continuous operation” mode. The prime mover intake air temperature and the load required for selecting the fresh air supply amount are introduced from the sensors 12 and 13 to the fresh air supply amount reading unit 38, thereby enabling the supply amount to be read. As a result of determining “No” in FIG. 20, the read trigger is not sent to the fresh air supply amount reading unit 38 and the prime mover intake air temperature and the load are input, but the supply amount is not read out. It is in.

  The above series of flows will be described with reference to a flowchart. The description includes not only the “automatic blower operation stop switching” mode but also the “continuous blower operation” and “continuous fan operation” modes. FIG. 1 shows a configuration that can handle either mode, and its control is shown in FIG. Incidentally, FIG. 8 and FIG. 9 described that the elements that only contribute to the other modes are removed and displayed in order to facilitate understanding of the “always blower stop” mode. Needless to say, it can be considered as one of the cogeneration systems if it is regarded as a “blower-less system” that does not perform the mode or “automatic blower operation stop switching” mode. However, with reference to FIG. 2 which can be adapted to any mode as described above, “blower continuous stop”, “fan normal operation”, and “blower stop automatic switching” will be described in order.

  First, the overall development of exhaust gas tracking control will be described with reference to FIG. This is how to transition from form A to form B, how to switch from form C (= form A) to form D, how to transition from form D to form E, It shows how to move from Form F to Form G. Of course, the reverse operation mode will also be described. Before explaining these operations, the basic switch concept introduced in the system will be explained. The switch is used to select a “blower continuous operation” mode, a “blower continuous stop” mode, and a “blower operation stop automatic switching” mode. There are various types of switches, but FIG. 24 shows them in an easy-to-understand manner with a relay circuit. This mode selection switch 51 is interposed in the control power supply circuit, and controls the driving of the electric motor 20 placed in the power supply circuit together with the operation of the fresh air supply necessity determination unit 34.

The mode selection switch 51 is installed in a control panel (not shown), and has a contact for continuous operation for selecting the “blower continuous operation” mode and an automatic switching contact for selecting the “blower operation stop automatic switching” mode. And when the contactor does not touch any of the contact points, the “blower always stop” mode is set. 24 includes a selection mechanism that takes one of the solid line, the alternate long and short dash line, and the broken line in the upper left part of FIG. 24 and relay coils R ₁ , R ₂ , R ₃ interposed in the control circuit. In FIG. 2, the coil group is abbreviated as 51. When the relay coil R ₄ is finally excited by the mode selection switch 51, the normally open contact r ₄ on the power supply circuit is turned on, and the electric motor 20 is driven. The fresh air supply necessity determination unit 34 has four contacts for determining “necessity of fresh air supply” as to whether or not the “evaporation amount expansion requirement” is satisfied, and the exhaust gas temperature, the evaporation amount, and the steam When the contacts r _T , r _Q , r _PE , r _PI and the relay coils R ₁ , R ₂ , R ₃ are energized when the pressure and the amount of PID tracking exceed the thresholds described later, and the relay coils R ₁ , R ₂ , R ₃ are excited. It includes normally open contacts r ₁ , r ₂ , r ₃ that are conducting.

The operation of the switch will be briefly described. When the contact selects the “continuous operation” contact, the relay coil R ₁ is energized, and the normally open contact r ₁ becomes conductive to energize the relay coil R ₄ . As a result, the normally open contact r ₄ is conducted and the electric motor 20 is rotated, so that the blower 19 is always in an operating state. When the contactor selects the “automatic switching” contact, the relay coil R ₁ is placed in a demagnetized state and the normally open contact r ₁ is opened, while R ₃ is excited to open the normally open contact r ₃ . Conduct. If none of the _normally open contacts r _T , r _Q , r _PE , r _PI is conducted, that is, if the determination of “required fresh air supply” has not been made, the relay coil R ₂ is placed in a demagnetized state. Since the normally open contact r ₂ is not conductive, the relay coil R ₄ is not excited, and the normally open contact r ₄ interrupts the power circuit and does not drive the motor 20. In this state, if any one of the _normally open contacts r _T , r _Q , r _PE , r _PI is conducted, that is, the “evaporation requirement” for switching from form C to form D is satisfied. if the relay coil R ₂ is energized, normally open contacts r ₄ by the excitation of the relay coil R ₄ due to the normally open contact r ₂ is conducting to conduct power circuit, the electric motor 20 is driven. Since the relay coils R ₁ and R ₃ are not excited unless the contact of the “continuous operation” contact or the “automatic switching” contact is selected, the normally open contacts r _T , r _Q , r _{Even if one of PE} and _rPI becomes conductive, the relay coils R ₂ and R ₄ are not excited and the electric motor 20 is not driven.

  Return explanation from switch to control. The overall development of exhaust gas tracking control will be described with reference to the flowchart of FIG. First, it is assumed that the motor intake air temperature is 15 ° C. and the load is 75%. If “always stop” is selected with the mode selection switch 51 in FIG. 1, the mode is “always blower stop” mode, so that the requirements for applying the boiler overload exit operation in S2 are satisfied through step 1 (hereinafter referred to as S1). You can see what they are doing. This is done in S2A and S2B in the left column of FIG. 25, the boiler inlet exhaust gas temperature by the temperature sensor 22 is lower than 850 ° C., and the amount of evaporation of the boiler detected by the steam flow meter 25 is fresh in the exhaust heat boiler. If the evaporation amount is less than 26.0 t / h, which is achievable without supply, it is not necessary to apply the boiler overload escape operation (S2D), and the state of FIG. That is, the PID tracking amount is calculated in S3 of FIG. 23, and the opening degree of the fuel flow control valve 16 is adjusted so as to be the tracking amount (S4).

  In S2, that is, in S2A and S2B in FIG. 25, if at least the boiler inlet exhaust gas temperature is 850 ° C. or higher, or the boiler generated evaporation is 26.0 t / h or higher, boiler overload escape operation must be applied (S2C ), A transition trigger is issued from the boiler overload escape operation application necessity determining unit 35 in FIG. 26 as shown in FIG. 27 to change the conduction state of the information transmission changing unit 36, and the state is changed from the form A to the form B. Then, the process proceeds to S5 and the above-described step (3-3) is taken to select the minimum amount of renewal (S6), and the opening of the fuel flow control valve 16 is adjusted so as to be the amount of remnant ( S4 in FIG. Returning to S1, S2 is reached, and the boiler overload escape operation which has been applied if the exhaust gas temperature is lower than 850 ° C. and the evaporation amount is lower than 26.0 t / h in S2A and S2B in the left column of FIG. Becomes unnecessary (S2D). Accordingly, the transition trigger that has been output from the boiler overload take-off operation application necessity determination unit 35 in FIG. 27 disappears, and the information transmission change unit 36 is returned to the form A in FIG. become.

  Next, as illustrated on the left side of FIG. 16, if “continuous operation” is selected by the mode selection switch 51, the “blower continuous operation” mode is set, and after step 1 of FIG. It is checked whether the boiler overload escape operation application requirements of S8 are satisfied. This is done in S8A and S8B in the right column of FIG. 25, the boiler inlet exhaust gas temperature by the temperature sensor 22 is lower than 850 ° C., and the boiler generated evaporation amount by the steam flow meter 25 is achievable when the fresh air supply is present. If it is less than 30.3 t / h, it is not necessary to apply the boiler overload escape operation (S8D), and the state shown in FIG. That is, the PID tracking amount is calculated in S3 of FIG. 23, and the opening of the fuel flow control valve 16 is adjusted so as to be the tracking amount (S4 of FIG. 23). In S8, that is, in S8A and S8B of FIG. 25, if at least the boiler inlet exhaust gas temperature is 850 ° C. or higher or the boiler generated evaporation amount is 30.3 t / h or higher, boiler overload escape operation must be applied (S8C ), A transition trigger is issued from the boiler overload escape operation application necessity determining unit 35 in FIG. 16 as shown in FIG. 19 to change the conduction state of the information transmission changing unit 36, and the state is changed from the form F to the form G. Then, the process proceeds to S9 and the above-described step (3-6) is taken to select the minimum amount of renewal (S6), and the opening of the fuel flow control valve 16 is adjusted so as to be the amount of remnant ( S4).

  Returning to S1 and reaching S7, if the exhaust gas temperature is lower than 850 ° C. and the evaporation amount is lower than 30.3 t / h in S8A and S8B in the right column of FIG. Becomes unnecessary (S8D). The transition trigger output from the boiler overload break-off operation application necessity determination unit 35 in FIG. 19 disappears, and the information transmission changing unit 36 is brought back to the original state and returned to form F (FIG. 16). In the “blower continuous operation” mode, the fresh air supply amount reading unit needs to be activated. For this reason, when the touch of the mode selection switch 51 becomes the “continuous operation” contact, for example, the limit switch L / A read trigger indicated by a thick dashed line in FIGS. 16 and 19 is generated by operating S or the like. Incidentally, the activation trigger may also be entered from the fresh air supply necessity determination unit 34 in the “blower operation stop automatic switching” mode to be described later. The supply amount reading unit 38 is connected.

Next, as shown in FIG. 20, if “automatic switching” is selected by the mode selection switch 51, the “blower operation stop automatic switching” mode is set, and the process reaches step S <b> 10 through steps 1 and S <b> 7 of FIG. You can see if the blower is in operation. This can be known depending on whether the normally open contact r ₄ of the power supply circuit in terms of the FIG. 24 is conductive. Although its detection is also omitted from FIG. 24 because it is known, the blower unless rendered conductive contact r ₄ is confirmed to be stopped, the process proceeds to S12. If none of S12A to S12D in FIG. 28 is satisfied, the fan is not driven and the stop is maintained (S13). Form C is maintained and the state of FIG. 20 is maintained. That is, the PID tracking amount is calculated in S3 of FIG. 23, and the opening degree of the fuel flow control valve 16 is adjusted so as to be the tracking amount (S4).

  If any of S12A to S12D in FIG. 28 is satisfied, the blower must be operated (S14). As shown in FIG. 21, a read trigger is issued from the fresh air supply necessity determining unit 34 in FIG. 20 to activate the fresh air supply amount reading unit 38, and thereafter, a necessary fresh air supply amount is obtained to obtain a fresh air supply amount adjustment command. Is output to the unit 41. In the case of inverter control, the electric motor 20 is driven at the read frequency. When switching to the form D, the state shown in FIG. 20 is obtained. Thereafter, it is checked whether the boiler overload escape operation application requirement of S8 in FIG. 23 is satisfied. This is done in S8A and S8B in the right column of FIG. 25. If the exhaust gas temperature is lower than 850 ° C. and the evaporation amount is lower than 30.3 t / h, it is not necessary to apply the boiler overload release operation (S8D). 21 is placed in the state of FIG. The PID tracking amount is calculated and the opening of the fuel flow control valve 16 is adjusted (S4 in FIG. 23). On the other hand, if at least one of S8, that is, S8A and S8B in FIG. 25, corresponds to the boiler overload take-off operation (S8C). A transition trigger as shown in FIG. 22 is issued from the boiler overload take-off operation application necessity determining unit 35 in FIG. 21 to change the conduction state of the information transmission changing unit 36, and the state D is changed to the state of FIG. . Then, the process proceeds to S9 in FIG. 23, and the above-described (3-6) step is taken to select the minimum amount of renewal, and the opening of the fuel flow control valve 16 is adjusted so as to be the amount of remnant ( S4). Of course, the blower continues to operate at the previously specified frequency.

  Returning to S1 and reaching S7, if the exhaust gas temperature is lower than 850 ° C. and the evaporation amount is lower than 30.3 t / h in S8A and S8B in the right column of FIG. Becomes unnecessary (S8D). The transition trigger output from the boiler overload break-off operation application necessity determination unit 35 in FIG. 22 disappears, and the information transmission change unit 36 is turned on to return to the form D in FIG. Returning to S1, via S7 to S10, if any of S15A to S15D in FIG. 29 is not satisfied, the operation of the blower is maintained (S14). Form D is maintained and the state of FIG. 21 is continued. That is, the PID tracking amount is calculated in S3 of FIG. 23, and the opening degree of the fuel flow control valve 16 is adjusted so as to be the tracking amount (S4).

  If any of S15A to S15D in FIG. 29 is satisfied, the blower is stopped (S13). That is, the “evaporation amount expansion” operation is canceled. The reading trigger that has been output from the fresh air supply necessity determination unit 34 in FIG. 21 disappears as shown in FIG. 20, the function of the fresh air supply amount reading unit 38 stops, and the mode D is reversed to the mode C. Thereafter, the PID tracking amount is calculated in S3 of FIG. 23, and the opening 16 of the fuel flow control valve is adjusted so as to be the tracking amount (S4). Note that measures for preventing chattering are taken in S12A to S12D in FIG. 28 and S15A to S15D in FIG. The “predetermined amount exceeding the maximum allowable boiler operation temperature” described in the (4-1) step is 20 ° C., which is described in S12A. Therefore, the “temperature exceeding the maximum allowable boiler operation temperature by a predetermined amount”, that is, the “new air supply start temperature” is 870 ° C. The “predetermined amount lower than the boiler inlet exhaust gas temperature 806 ° C. corresponding to the engine intake air temperature 15 ° C. and the load detection value 75%, etc.” described in the same process is 25 ° C., which is described in S15A. ing. Accordingly, the “temperature lower by a predetermined amount from the boiler inlet exhaust gas temperature 806 ° C. corresponding to the intake air temperature of the prime mover 15 ° C. and the detected value of load, eg 75%” is 781 ° C.

  As described in the step (4-2), “a predetermined amount exceeding an achievable evaporation amount when there is no fresh air supply calculated according to a prime mover intake air temperature of 15 ° C. and a load of 75%, for example, 26.0 t / h "Is 0.3 t / h, which is described in S12B. Therefore, “evaporation amount exceeding a predetermined amount from the achievable evaporation amount 26.0 t / h when no fresh air supply is calculated according to the engine intake air temperature 15 ° C. and the load 75%”, that is, “new air supply start” The “evaporation amount” is 26.3 t / h. The “predetermined amount exceeding the achievable evaporation amount 26.0 t / h when no fresh air is supplied” described in the same process is 0.1 t / h, which is described in S15B. Therefore, the “evaporation amount that exceeds the achievable evaporation amount 26.0 t / h without fresh air supply by a predetermined amount but less than the fresh air supply start evaporation amount”, that is, the “new air supply stop evaporation amount” is 26. 1 t / h.

  The “predetermined amount lower than the set pressure” described in the step (4-3) is 0.1 MPa, which is described in S12C. Therefore, the “steam pressure lower than the set pressure by a predetermined amount”, that is, the “new air supply start steam pressure” is 1.17 MPa. The “predetermined amount exceeding the set pressure” described in the step is 0.1 MPa, which is described in S15C. Therefore, the “steam pressure exceeding the set pressure by a predetermined amount”, that is, “new air supply start steam pressure” is set to 1.37 MPa.

The (4-4) "predetermined amount below the add焚量920 nm ³ / h corresponding to the detected value of the intake air temperature 15 ℃ with 75% load of the prime mover," as mentioned in step is a 10 Nm ³ / h, This is described in S12D. Therefore, the “mechanism amount that falls below a predetermined amount from the 920 Nm ³ / h corresponding to the detected value of the intake air temperature of 15 ° C. and the load of 75%”, that is, the “new air supply start memorial amount” is 910 Nm. ³ / h. The “predetermined amount lower than the amount 920 Nm ³ / h corresponding to the detected value of the intake air temperature and load of the motor” described in the same process is 20 Nm ³ / h, which is described in S15D. Therefore, “the amount of tracking that is lower than the amount of tracking 920 Nm ³ / h corresponding to the detected value of the intake air temperature and the load of the prime mover by a predetermined amount but less than the amount of starting fresh air supply”, that is, “fresh air supply” The “stop tracking amount” is set to 900 Nm ³ / h.

Any of the numbers described above corresponds to the above-described threshold value, and with this as a boundary, the contacts r _T , r _Q , r _PE , r _PI (see FIG. 24) of the fresh air supply necessity determination unit 34 operate as switches. It will be. Needless to say, the chattering prevention margin is merely an example. These may be fixed values, but different values may be given depending on the difference between the engine intake air temperature and the load.

  According to this example, it can be seen that the control can be escaped by a very simple control by calculating the amount of suppression and tracking based on the factor from overheating of the boiler heat transfer tube, which is an overload factor, and excessive evaporation. In order to respond to the increase in consumption on the steam demand side, the presence or absence of the requirement is grasped in order to expand the evaporation amount, and the transition to energy saving operation when there is no need for expansion of the steam demand side is made smoothly without causing chattering. It will be.

  In the cogeneration system described above, the blower can be always operated with the power generation device stopped as in the form H mentioned in Table 3 of FIG. This is the operation shown by the solid line in FIG. Thus, steam can be obtained even when the power generation device is not operating. The blowing amount at this time is output from the activated fresh air supply amount reading unit 38, the driving frequency thereof is 60 Hz, and the amount of remedy is obtained by PID calculation based on the vapor pressure.

  By the way, it has been described that the exhaust heat boiler is a boiler that generates steam. However, it may be replaced with a boiler that generates hot water or hot oil. In order to keep hot water and hot oil at the set temperature, the amount of exhaust gas added is determined by PID control based on the temperature of the detected hot water and hot oil, the evaporation amount is replaced with the hot water and hot oil amount, and the steam is hot water・ If the pressure is replaced with warm oil / hot oil temperature, it will not change with a steam generating boiler.

  More specifically, a PID calculation is performed based on the detected hot water temperature / hot oil temperature, and the amount of replenishment in the introduced exhaust gas is determined in order to maintain the set hot water temperature / hot oil temperature. The expected amount of fresh air supply during the process of (1) and the expected amount of fresh air supply are the group of expected follow-up amounts that generate the set hot water temperature and hot oil temperature specific to the exhaust heat boiler. The expected amount of fresh air supply should be used, and the amount of hot water and hot oil achieved can be substituted for the amount of evaporation that can be achieved. In addition, in the case of the “fanless system” as shown in FIG. 8 and FIG. 9, the expected amount of renewal without supply of fresh air during the process (1) causes the set pressure specific to the exhaust heat boiler to be calculated. Instead of a group of predicted tracking amounts, a group of predicted tracking amounts that generate the set hot water temperature and hot oil temperature specific to the exhaust heat boiler are calculated, and instead of the achievable evaporation amount, the achieved hot water and hot oil amounts are That's fine. Thus, the versatility of the present invention is asked in that it can be applied to hot water / hot oil boilers.

  By the way, in the case of form C and D & E, the waste heat boiler of the capability exceeding the evaporation amount which can be generated by chasing exhaust gas is selected at the time of cogeneration system planning. However, since fresh air is supplied to the exhaust gas and the amount of replenishment can be increased, even if there is a demand for an excessive amount of evaporation exceeding the planned time from the steam demand side, it can be met It becomes like this. In other words, if the blower is not operated, it will be operated only by purging the exhaust gas from the power generation device, and if the blower is operated, fresh air is mixed with the exhaust gas and the amount of renewal is increased. An allowable maximum evaporation amount that can be exerted or an amount close thereto can be generated. Even if an overload factor of the boiler occurs during the operation to expand the evaporation amount, the suppression memorizing amount is selected in consideration of the prime mover intake air temperature and the load of the power generator, and the boiler is designed to escape from the overload. Is protected. At this time, since it does not drop at a stroke to the minimum amount of boiler operation, the amount of evaporation does not decrease or fluctuate, and the operation on the steam demand side is not rapidly modulated or disrupted.

  DESCRIPTION OF SYMBOLS 1 ... Power generation device, 2 ... Exhaust heat boiler, 3 ... Distribution duct, 4 ... Exhaust gas, 5 ... Fresh air, 6 ... Fresh air supply device, 7 ... Motor | power_engine, 8 ... Generator (generator), 9 ... Steam, 10 ... 13A natural gas, 11 ... Steam drum, 12 ... Intake temperature sensor, 13 ... Load sensor, 14 ... Remembrance device, 15 ... Remembrance burner, 16 ... Fuel flow control valve, 17 ... Fuel flow meter, 18 DESCRIPTION OF SYMBOLS ... Fresh air mixing box, 19 ... Blower, 20 ... Electric motor, 21 ... Fresh air supply control valve, 22 ... Exhaust gas temperature sensor, 23 ... Drum pressure sensor, 24 ... Steam demand side, 25 ... Steam flow meter, 26 ... Additional Soot amount calculation control means, 29 ... PID control unit, 30 ... fuel amount adjustment command unit, 31 ... form change determination unit, 34 ... new air supply necessity determination unit, 35 ... boiler overload escape operation application necessity determination unit, 38 ... Fresh air supply amount reading unit, 39 ... Necessary Overload tracking amount calculation unit, 40 ... minimum tracking amount selection unit, 41 ... fresh air supply command unit, 43 ... medium amount reading unit corresponding to intake air temperature / load, 44 ... temperature during overload vs. tracking amount chart generation unit, 45... temperature overload escape tracking amount calculation unit, 46... evaporation amount during overload vs. tracking amount chart generation unit, 47... evaporation amount overload escape tracking amount calculation unit, 51 ... mode selection switch.

Claims (13)

An exhaust heat boiler in which the amount of exhaust gas to be introduced is determined by calculation based on detected steam pressure to maintain the steam pressure of the boiler at a set pressure, and exhaust gas to be supplied to the exhaust heat boiler In the exhaust gas tracking control method in a cogeneration system equipped with a prime mover generated when the generator is driven,
(1) Exhaust gas generated according to several typical prime mover intake air temperatures during operation of the prime mover and several typical loads at that time is calculated in advance at the exhaust heat boiler inlet in calculation. Calculates a group of “predicted tracking amounts” that do not exceed the “maximum allowable temperature for boiler operation” and generates the set pressure specific to the exhaust heat boiler, and also calculates the “attainable evaporation” at this time. Process to keep,
(2) In preparation for when the detected value of the boiler overload factor corresponds to overload operation, “the maximum value in the expected amount of tracking” as the amount of memory until the “overload lower limit value” of the factor is detected And the `` minimum value in the expected tracking amount '' is used as the tracking amount when detecting the `` overload upper limit value '' of the factor, and an intermediate value between the overload lower limit value and the overload upper limit value is detected. As a memorial amount, a process of applying the “intermediate corresponding value” in a series of values maintaining a continuously decreasing relationship from the maximum value to the minimum value,
(3) When the exhaust gas supplied from the prime mover is being chased, if the detected value of the overload factor exceeds the “overload lower limit value”, “the prime mover at that time out of the expected follow-up amount” "Additional amount corresponding to detected value of intake air temperature and load" and "Additional amount given corresponding to detected value of overload factor among a series of values from the maximum value to the minimum value in the estimated additional amount" Opening of the fuel flow control valve of the reheating burner that raises the temperature of the exhaust gas from the prime mover so that the remnant amount is the smallest of the “reed amount” and the “PID renewal amount obtained by the PID control”. On the other hand, a new air supply amount corresponding to a detected value of the intake air temperature and load of the prime mover in the “predicted fresh air supply amount” of the “new air supply expected amount” is added to the upstream side of the follow-up burner. A step of adjusting the discharge amount of the blower that feeds air; (4) supplied from the prime mover; Increased steam consumption on the steam demand side when determining the PID tracking amount to keep the steam pressure of the boiler at the set pressure without mixing fresh air when tracking exhaust gas When the "evaporation amount expansion requirement" based on the above is satisfied, fresh air is supplied to the exhaust gas supplied from the prime mover from that point, and the amount of remedy is determined by subsequent "PID calculation" based on the subsequent vapor pressure If the “evaporation amount expansion requirement” is not satisfied, the mixing of fresh air with the exhaust gas supplied from the prime mover is stopped and the additional amount is calculated based on the subsequent vapor pressure. The process defined by
An exhaust gas tracking control method in a cogeneration system characterized by comprising: In the step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when fresh air is supplied”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The step (2) is performed when the overload factor is detected when fresh air is supplied to perform a follow-up operation, and the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, The overload lower limit is the “maximum allowable boiler operation temperature” and the “evaporation amount achievable with fresh air supply calculated according to the prime mover intake air temperature and load”, and the overload upper limit is the maximum allowable boiler operation It is the “exceeding maximum temperature” that is obtained by adding a predetermined excess permissible temperature to the temperature, and the achievable evaporation amount with a fresh air supply is added to the predetermined excess permissible evaporation amount. Maximum evaporation "
In the step (3), the reheating is performed by supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit value is “boiler operation permissible value”. `` Maximum temperature '' and `` Evaporation amount achievable with fresh air supply '', and the amount of memory that corresponds to the detected value of the engine intake air temperature and load at that time is 2. The exhaust gas tracking control method for a cogeneration system according to claim 1, characterized in that it is a “tracking amount corresponding to the detected intake temperature and load value of the prime mover at that time of the expected tracking amount”. In the step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when fresh air is supplied”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The step (2) is performed when the overload factor is detected when fresh air is supplied to perform a follow-up operation, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is "Boiler operation allowable maximum temperature", the overload upper limit value is "excess maximum temperature" obtained by adding a predetermined excess allowable temperature to the boiler operation allowable maximum temperature,
In the step (3), the reheating is performed by supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “boiler operation allowable maximum temperature”, Of the expected amount of remedy, the amount of remedy corresponding to the detected value of the intake air temperature and load of the prime mover at that time is `` the detected value of the prime mover intake temperature and load at that time of the expected amount of remedy when fresh air is supplied 2. The exhaust gas tracking control method in the cogeneration system according to claim 1, wherein the amount is a tracking amount corresponding to “1. In the step (1), with the assumption that fresh air is mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when fresh air is supplied”, and the achievable evaporation amount is “fresh air supply” "Evaporation amount that can be achieved at any time", in addition, "Estimated amount of fresh air supply" required for "Estimated amount of fresh air supply" is calculated,
The step (2) is performed when the overload factor is detected when fresh air is supplied to perform a follow-up operation. The overload factor is “boiler evaporation”, and the overload lower limit value is “ The evaporation amount achievable with fresh air supply calculated according to the prime mover intake air temperature and the load at that time ”, and the overload upper limit value is an allowable excess determined in advance for the achievable evaporation amount with fresh air supply. It is the `` maximum excess evaporation amount when there is fresh air supply '' with the evaporation amount added,
In the step (3), the replenishment is performed by supplying fresh air, the overload factor is “boiler evaporation”, and the lower limit of the overload is “achievable evaporation when fresh air is supplied”. Of the expected amount of tracking, the amount of tracking corresponding to the detected value of the intake air temperature and load of the motor at that time is `` the estimated intake amount and load of the motor at that time of the estimated amount of tracking with fresh air supply '' The exhaust gas tracking control method in the cogeneration system according to claim 1, wherein the amount is a tracking amount corresponding to the detected value.   The “evaporation amount expansion requirement is satisfied” in the step (4) means that the detected value of the boiler inlet exhaust gas temperature is equal to or higher than the “new air supply start temperature” that exceeds the maximum allowable boiler operation temperature by a predetermined amount. The “evaporation amount expansion requirement cannot be satisfied” means that the detected value of the boiler inlet exhaust gas temperature is determined in advance from the boiler inlet exhaust gas temperature corresponding to the prime mover intake air temperature and the load detected value at that time. 5. The exhaust gas renewal control method in a cogeneration system according to claim 2, wherein the exhaust gas renewal control method is equal to or lower than a “fresh air supply stop temperature” that is lower by a specified amount.   The “evaporation amount expansion requirement is satisfied” in the step (4) can be achieved when the detected value of the boiler evaporation amount is not supplied with fresh air calculated according to the prime mover intake air temperature and the load at that time. It means that it exceeds the “fresh air supply start evaporation amount” that exceeds the evaporation amount by a predetermined amount. The “evaporation amount expansion requirement is not satisfied” means that the detected value of the boiler evaporation amount is the fresh air supply. 5. The fuel cell according to claim 2, wherein the evaporation amount exceeds a predetermined amount by a predetermined amount but is less than the “fresh air supply stop evaporation amount” smaller than the fresh air supply start evaporation amount. An exhaust gas tracking control method for a cogeneration system according to claim 1.   The “evaporation amount expansion requirement is satisfied” in the step (4) means that the detected value of the boiler vapor pressure is equal to or lower than the “new air supply start vapor pressure” that is lower than the set pressure by a predetermined amount. Yes, the “evaporation amount expansion requirement is not satisfied” is characterized in that the detected value of the boiler steam pressure is equal to or higher than the “new air supply stop steam pressure” which is higher than the set pressure by a predetermined amount. The exhaust gas renewal control method in the cogeneration system as described in any one of Claims 2 thru | or 4.   The “evaporation amount expansion requirement is satisfied” in the step (4) means that the PID tracking amount corresponds to the detected value of the intake air temperature and the load of the prime mover among the predicted tracking amount when there is no fresh air supply The “fresh air supply start memorial amount” which is lower than the predetermined memorized amount by a predetermined amount or more, and the “evaporation amount expansion requirement is not satisfied” means that the PID memorized amount is the fresh air amount. Of the expected follow-up amount at the time of no supply, it falls below a predetermined amount from the follow-up amount corresponding to the detected intake air temperature and load of the motor at that time, but is smaller than the fresh air supply start follow-up amount 5. The exhaust gas tracking control method in a cogeneration system according to claim 2, wherein the exhaust gas tracking control method is equal to or less than a “supply stop tracking amount”. An exhaust heat boiler in which the amount of exhaust gas to be introduced is determined by calculation based on detected steam pressure to maintain the steam pressure of the boiler at a set pressure, and exhaust gas to be supplied to the exhaust heat boiler In the exhaust gas tracking control method in a cogeneration system equipped with a prime mover generated when the generator is driven,
(1) Exhaust gas generated according to several typical prime mover intake air temperatures during operation of the prime mover and several typical loads at that time is calculated in advance at the exhaust heat boiler inlet in calculation. Calculates a group of “predicted tracking amounts” that do not exceed the “maximum allowable temperature for boiler operation” and generates the set pressure specific to the exhaust heat boiler, and also calculates the “attainable evaporation” at this time. Process to keep,
(2) In preparation for when the detected value of the boiler overload factor corresponds to overload operation, “the maximum value in the expected amount of tracking” as the amount of memory until the “overload lower limit value” of the factor is detected And the `` minimum value in the expected tracking amount '' is used as the tracking amount when detecting the `` overload upper limit value '' of the factor, and an intermediate value between the overload lower limit value and the overload upper limit value is detected. As a memorial amount, a process of applying the “intermediate corresponding value” in a series of values maintaining a continuously decreasing relationship from the maximum value to the minimum value,
(3) When the exhaust gas supplied from the prime mover is being pursued and the “overload lower limit value” is exceeded, “the detection of the intake air temperature and the load of the prime mover at that time out of the estimated follow-up amount” “A memorizing amount corresponding to a value”, “a memorizing amount given corresponding to a detected value of an overload factor among a series of values from a maximum value to a minimum value in the expected memorizing amount”, “ A step of adjusting the opening of the fuel flow control valve of the tracking burner that raises the temperature of the exhaust gas from the prime mover so as to be the smallest tracking amount among the “PID tracking amount determined by PID control”;
An exhaust gas tracking control method in a cogeneration system characterized by comprising: In the step (1), in the state where fresh air is not mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when no fresh air is supplied”, and the achievable amount of evaporation is “when no fresh air is supplied” Achievable evaporation "
The step (2) is performed when the overload factor is detected when a refueling operation is performed without supplying fresh air, and the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”. The overload lower limit is the “maximum allowable boiler operation temperature” and the “evaporation amount achievable without fresh air supply calculated according to the prime mover intake air temperature and load”, and the overload upper limit is the maximum allowable boiler operation temperature. Is the “exceeding maximum temperature” with a pre-determined allowable permissible temperature added, and the achievable maximum evaporation when there is no fresh air supply plus the pre-determined allowable permissible evaporation amount. Amount ",
In the step (3), the reheating is performed without supplying fresh air, the overload factors are “boiler inlet exhaust gas temperature” and “boiler evaporation amount”, and the overload lower limit value is “boiler operation allowable The maximum temperature ”and the“ evaporation amount achievable without fresh air supply ”, and the amount of memory that corresponds to the detected intake temperature and load of the prime mover at that time is 10. The exhaust gas tracking control method for a cogeneration system according to claim 9, wherein the exhaust gas tracking control method corresponds to a detected value of the intake air temperature and load of the motor at that time in the expected tracking amount. In the step (1), in the state where fresh air is not mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when no fresh air is supplied”, and the achievable amount of evaporation is “when no fresh air is supplied” Achievable evaporation "
The step (2) is performed when the overload factor is detected in a chasing operation without supplying fresh air. The overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is set. Is the “maximum allowable boiler operation temperature”, and the overload upper limit value is the “excess maximum temperature” obtained by adding a predetermined excess allowable temperature to the maximum allowable boiler operation temperature,
In the step (3), the reheating is performed without supplying fresh air, the overload factor is “boiler inlet exhaust gas temperature”, and the overload lower limit value is “boiler operation allowable maximum temperature”, Of the expected amount of remedy, the amount of remedy corresponding to the detected value of the intake air temperature and load of the prime mover at that time is `` the detected value of the intake temperature and load of the prime mover at that time of the expected amount of remedy when no fresh air is supplied The exhaust gas tracking control method in the cogeneration system according to claim 9, wherein the amount is a tracking amount corresponding to. In the step (1), in the state where fresh air is not mixed with the exhaust gas, the expected amount of tracking is “the amount of expected tracking when no fresh air is supplied”, and the achievable amount of evaporation is “when no fresh air is supplied” Achievable evaporation "
The step (2) is performed when the overload factor is detected in a chasing operation without supplying fresh air, the overload factor is “boiler evaporation”, and the overload lower limit value is “ `` Achievable evaporation amount without fresh air supply calculated according to prime mover intake air temperature and load '' at that time, and the overload upper limit value is the allowable excess evaporation that is predetermined for the achievable evaporation amount without fresh air supply It is the "maximum evaporation amount when there is no fresh air supply"
In the step (3), the reheating is performed without supplying fresh air, the overload factor is “boiler evaporation amount”, and the lower limit of the overload is “evaporation amount achievable without supply of fresh air”. Yes, the amount of memory that corresponds to the detected value of the engine intake air temperature and load at that time in the expected amount of tracking is `` the amount of engine intake air temperature and load at that time out of the estimated amount of tracking when no fresh air is supplied The exhaust gas tracking control method in the cogeneration system according to claim 9, wherein the amount is a tracking amount corresponding to a detected value.   In the exhaust heat boiler, instead of a steam generating boiler, the amount of exhaust gas to be added is determined by PID control based on the temperature of the detected hot water / hot oil in order to keep the hot water / hot oil at a set temperature. 13. The evaporation amount is replaced with hot water / hot oil amount, the steam is replaced with hot water / hot oil, and the pressure is replaced with hot water / hot oil temperature. An exhaust gas tracking control method in the cogeneration system described in any one of the above.