JP2007232249A - Heat source machine, its control method, and heat source system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a turbo refrigerating machine capable of supplying cold water while keeping its constant temperature even when the turbo refrigerating machine is stopped by problems. <P>SOLUTION: In the turbo refrigerating machine 3 comprising an operating panel 4 for monitoring a state of the turbo refrigerating machine 3 cooling the cold water flowing in from an external load and controlling the turbo refrigerating machine 3, a start-up request signal requiring the start of the other turbo refrigerating machine is generated, when an operation stop prediction that the operation of the turbo refrigerating machine 3 is stopped after a prescribed time because of the abnormality in the state of the turbo refrigerating machine 3, is performed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat source machine, for example, a turbo refrigerator, a control method thereof, and a heat source system.

As a heat source device of a heat source system that supplies cold water (heat medium) used in a factory process at a constant temperature, a turbo refrigerator that is a large-capacity heat source device is frequently used. This turbo refrigerator uses a centrifugal turbo compressor as a compressor. Since the turbo compressor is a high-speed rotating machine, it is designed to stop safely so as not to be damaged in an abnormal state. Specifically, when a sensor connected to the microcomputer board that controls the turbo chiller is disconnected or indicates an abnormality such as an overrange, the turbo chiller is abnormally stopped (tripped).
However, if the centrifugal chiller trips, the temperature of the cold water supplied to the factory process fluctuates, which affects the quality (yield) of products produced in the factory.

On the other hand, in the field of air conditioning equipment, a technique is known in which when any outdoor unit of an air conditioning system having a plurality of outdoor units is stopped, backup is performed by another outdoor unit (see Patent Documents 1 and 2).
Moreover, the technique about failure prediction of the compressor etc. which comprise a refrigeration cycle apparatus is also known (refer patent document 3).

JP-A-7-332816 JP 2001-201199 A JP 2005-241089 A

However, in Patent Documents 1 and 2, although knowledge of how to perform backup by another outdoor unit when one of the outdoor units stops is shown, other smoothly when the outdoor unit stops There is no information about starting up outdoor units. Therefore, even if the known technology is applied to a heat source system including a plurality of turbo chillers, the subsequent machine cannot be started smoothly when the operating turbo chiller is abnormally stopped.
Moreover, even if failure prediction of a compressor or the like is applied as in Patent Document 3, there is no way to deal with an event that can hardly be predicted such as disconnection of a sensor.
Therefore, there is a demand for a technology that can smoothly start the turbo chiller that is the subsequent machine before the temperature of the chilled water to be supplied changes significantly due to the abnormal stop of the operating turbo chiller.

  The present invention has been made in view of such circumstances, and even when the heat source device is stopped due to a malfunction, the heat source device capable of continuously supplying a heat medium at a constant temperature and its control. It is an object to provide a method and a heat source system.

In order to solve the above problems, the heat source machine, the control method thereof, and the heat source system of the present invention employ the following means.
In other words, the control device for a heat source device according to the first aspect of the present invention controls the heat source device by monitoring the state of the heat source device that supplies the cooled or heated heat medium flowing from the external load to the external load. A control device for a heat source machine, when an operation stop prediction is made to predict that the operation of the heat source machine will be stopped after a predetermined time due to an abnormality in the state of the heat source machine. A late start signal for requesting start of the vehicle is issued.

When the state of the heat source unit becomes abnormal and the operation stop prediction is predicted to stop the operation after a lapse of a predetermined time, by issuing a late start signal to start another heat source unit, Other heat source machines can be activated before the heat source machine stops. Since the operating heat source machine issues a late starter signal and stops after a predetermined time has elapsed, the predetermined time can be used as the start time of the late engine. And even if the heat source machine stops after a predetermined time has elapsed, since the start of the subsequent machine has already started, the heat medium supplied to the external load does not show a significant temperature fluctuation.
Examples of the heat source device include a turbo refrigerator and a screw chiller.

  Furthermore, the control device for the heat source unit of the above aspect monitors each state variable indicating various states of the heat source unit, and issues an alarm signal and continues operation when the state variable exceeds the first threshold value. When the state variable exceeds the first threshold and further exceeds the second threshold, it is determined that the operation cannot be continued and the heat source unit is abnormally stopped. The operation stop prediction is performed when a third threshold value set between the first threshold value and the second threshold value is exceeded.

The third threshold value is provided between the first threshold value for issuing the alarm signal and the second threshold value for determining that the operation cannot be continued. By providing the third threshold value, the operation stop prediction is performed. Since no other heat source device is activated in response to an alarm signal that can be returned to a normal operation state, a useless activation command is not issued. Moreover, since the late starter start signal can be issued before abnormal stop, the start time of the late starter can be secured.
Here, the state variables include, for example, the pressure of the condenser or the evaporator, the temperature of the lubricating oil that lubricates the driving unit of the compressor, the current value of the motor that drives the compressor, and the like.

  Furthermore, the control device for the heat source device according to the first aspect performs the operation stop prediction when an abnormality occurs in a sensor that measures various states of the heat source device, and the replacement value using another sensor is used as the value. The operation of the heat source unit is continued for a predetermined time.

  When an abnormality occurs in a sensor that measures various states of the heat source machine and the sensor is an important sensor for continued operation, it is common to immediately stop the operation. If this alternative value is used, the operation can be continued for a certain time. Thereby, a driving | running can be continued only for the predetermined time, and the starting time of a succeeding machine (other heat-source equipment) can be ensured.

  Furthermore, in the control device for a heat source apparatus according to each of the above-described aspects, the predetermined time is a time for which the other heat source apparatus to which the subsequent generator start signal is given is substantially completed for start-up.

By setting the predetermined time to a time when the starter machine almost completes startup, the heat medium can be supplied to the external load with almost no change in the temperature of the heat medium.
Although it depends on the capacity of the heat source unit, the predetermined time is, for example, about 3 minutes in the case of a turbo refrigerator.

  Moreover, the heat source machine concerning this invention is equipped with the control apparatus of the heat source machine of any one of the above-mentioned aspects.

  The heat source system according to the present invention includes a plurality of heat source devices that cool or heat a heat medium flowing from an external load and supplies the heat medium to the external load, and a system control device that controls each of the heat source devices. A heat source system, wherein at least one of the heat source units includes the control device for the heat source unit according to any one of the above-described aspects, and the system control unit is a late generator generated from the control unit for the heat source unit. The other heat source machine is activated by an activation signal.

  Since the control device for the heat source device of each aspect is provided, even if the heat source device stops due to some abnormality, the heat source can supply the heat medium to the external load with almost no change in the temperature of the heat medium A system can be realized.

  The method of controlling a heat source apparatus according to the present invention includes: a heat source that controls a heat source apparatus by monitoring a state of the heat source apparatus that cools or heats a heat medium flowing from an external load and supplies the heat medium to the external load. When the operation of the heat source unit is predicted to be stopped after a predetermined time due to an abnormality in the state of the heat source unit, the other heat source unit is started. It is characterized by issuing a requested late start signal.

When the state of the heat source unit becomes abnormal and the operation stop prediction is predicted to stop the operation after a lapse of a predetermined time, by issuing a late start signal to start another heat source unit, Other heat source machines can be activated before the heat source machine stops. Since the operating heat source machine issues a late starter signal and stops after a predetermined time has elapsed, the predetermined time can be used as the start time of the late engine. And even if the heat source machine stops after a predetermined time has elapsed, since the start of the subsequent machine has already started, the heat medium supplied to the external load does not show a significant temperature fluctuation.
Examples of the heat source device include a turbo refrigerator and a screw chiller.

  Since it was decided to stop after a lapse of a predetermined time after giving a late start signal to request the start to other heat source machines, even if the heat source machine stopped due to a malfunction, a heat medium with a substantially constant temperature was externally loaded. Can be supplied to.

Embodiments according to the present invention will be described below with reference to the drawings.
FIG. 1 shows a heat source system 1 according to a first embodiment of the present invention.
The heat source system 1 according to the present embodiment includes two turbo chillers (heat source units) 3.

Each turbo refrigerator 3 has an equivalent refrigeration capacity. The first turbo chiller 3a and the second turbo chiller (other heat source machine) 3b are each connected to an external load.
Each turbo chiller 3 is provided with an operation panel (heat source machine control device) 4 for performing operation control. The operation panel 4 is electrically connected to a system control panel (system control apparatus) 2 that controls the entire heat source system 1 so that bidirectional communication is possible. Therefore, the operation panel 4 can be operated from the remote system control panel 2. The operation panel 4 can also be operated by an operator near the turbo refrigerator 3.
As will be described later with reference to FIG. 3, the operation panel 4 not only outputs an alarm signal and a trip signal, but also outputs a start-up request signal (later-engine start signal).

Each turbo refrigerator 3 is provided with an evaporator 7 connected to the external load side and a condenser 13 connected to the cooling tower side.
The evaporator 7 is connected to return and forward chilled water pipes (heat medium pipes) 8a and 8b so that the chilled water heat medium circulates and flows to and from an external load. The return cold water pipe 8a is provided with a heat medium pump 12 for supplying a heat medium. The chilled water pipes 8a and 8b are connected and switched to the chilled water headers 10a and 10b or the hot water header according to the request of the external load. FIG. 1 shows a state where the cold water headers 10a and 10b are connected to the factory process side as an external load.

  A cooling tower 15 is connected to the condenser 13 via return and forward cooling water pipes 17a and 17b through which cooling water flows. In the cooling tower 15, cooling water is sprinkled and heat exchange is performed with the outside air. A cooling water pump 19 for supplying cooling water is provided in the return cooling water pipe 17a.

The heat source system 1 is provided with a system control panel 2 that controls the entire system. The heat source system control panel 2 controls each turbo chiller 3, the cooling tower 15, the heat medium pump 12, and the like.
Further, the system control panel 2 receives a startup request signal from the operation panel 4 of each turbo refrigerator 3.

FIG. 2 shows the configuration of the turbo refrigerator 3. The configuration shown in the figure is for the cooling operation.
Both the first turbo chiller 3a and the second turbo chiller 3b have the configuration shown in FIG. The turbo refrigerator 3 constitutes a two-stage compression and two-stage expansion cycle.

  The turbo refrigerator 3 includes a turbo compressor 23 that compresses a refrigerant, a condenser 13 to which cooling water pipes 13a and 13b are connected, an evaporator 7 to which cold water pipes 8a and 8b are connected, a condenser 13 and an evaporator. 7 and an intermediate cooler 27 provided between the two. A first expansion valve 29 is provided in the refrigerant pipe between the intermediate cooler 27 and the condenser 13, and a second expansion valve 30 is provided in the refrigerant pipe between the intermediate cooler 27 and the evaporator 7. It has been.

The turbo compressor 23 is a centrifugal compressor capable of obtaining a high pressure ratio. Oil lubrication is performed on a drive unit such as a bearing of the turbo compressor 23, and the temperature Tp of the lubricant is measured by a lubricant temperature sensor 23a. The output of the lubricating oil temperature sensor 23a is transmitted to the operation panel 4 (see FIG. 1).
The turbo compressor 23 includes an electric motor 37 and an inlet vane 35.
The electric motor 37 has a constant rotational speed depending on the power supply frequency, or is an inverter type, and is variably controlled. The electric motor 37 is provided with an ammeter 37a for measuring the motor current Am. The output of the ammeter 37a is transmitted to the operation panel 4. In the case of the inverter type, a current value is transmitted as a signal from the inverter control board.
The inlet vane 35 is provided on the upstream side of the refrigerant flow, and adjusts the flow rate of the flowing refrigerant. The opening degree of the inlet vane 35 is controlled by the control unit. By adjusting the opening degree of the inlet vane 35, the cold water outlet temperature T1 is controlled.

The condenser 13 is a shell-and-tube heat exchanger. Cooling water pipes 13a and 13b are connected to the condenser 13, and the water flowing in the cooling water pipes 13a and 13b exchanges heat with the refrigerant in the shell. The cooling water pipes 13a and 13b are connected to a cooling tower.
The condenser 13 is provided with a pressure sensor 13s so that the condensation pressure is measured. The output of the pressure sensor 13s is transmitted to the operation panel 4.

The evaporator 7 is a shell-and-tube heat exchanger. Cold water pipes 8a and 8b are connected to the evaporator 7, and water flowing through the cold water pipes 8a and 8b exchanges heat with the refrigerant in the shell. The cold water pipes 8a and 8b are connected to an external load, and cold water flows. A chilled water inlet temperature sensor 31a that measures the chilled water inlet temperature T0 before heat exchange is located upstream of the outgoing chilled water pipe 8a, and a chilled water that measures the chilled water outlet temperature T1 after heat exchange is located downstream of the return chilled water pipe 8b. Each outlet temperature sensor 31b is provided. Generally, the cold water inlet temperature T0 during cooling is set to 12 ° C., and the cold water outlet temperature T1 is set to 7 ° C.
The evaporator 7 is provided with a pressure sensor 7s so that the evaporation pressure is measured. The output of the pressure sensor 7s is transmitted to the operation panel 4.

The intercooler 27 is provided between the condenser 13 and the evaporator 7 and is a container in which the liquid refrigerant condensed inside is stored.
An intermediate pressure refrigerant pipe 27 a is connected between the intermediate cooler 27 and the intermediate stage of the turbo compressor 23. The lower end of the intermediate pressure refrigerant pipe 27a (upstream end of the refrigerant flow) is located in the upper space in the intermediate cooler 27 and sucks the gas refrigerant in the intermediate cooler 27.
In the intermediate cooler 27, the high-pressure liquid refrigerant from the condenser 13 evaporates, and the liquid refrigerant guided to the evaporator via the intermediate-pressure refrigerant pipe 27a is cooled by this latent heat of vaporization. Then, the gas refrigerant that has evaporated to near the saturation temperature is mixed with the gas refrigerant compressed from the low pressure to the intermediate stage in the turbo compressor 23 to cool the gas refrigerant compressed from the intermediate stage.
The intermediate cooler 27 is provided with a pressure sensor 27s for measuring the intermediate pressure Pm. The output of the pressure sensor 27 s is transmitted to the operation panel 4.

The first expansion valve 29 is provided between the condenser 13 and the intercooler 27, and is expanded by equal enthalpy by constricting the liquid refrigerant.
The second expansion valve 30 is provided between the evaporator 7 and the intercooler 27, and is expanded by equal enthalpy by constricting the liquid refrigerant.
The opening degree of each of the first expansion valve 29 and the second expansion valve 30 is controlled by the operation panel 4 serving as a control unit.

Next, the operation of the turbo refrigerator 1 having the above configuration will be described.
The turbo compressor 23 is driven by an electric motor 37 and is rotated at a predetermined frequency by inverter control by the operation panel 4 serving as a control unit. The opening degree of the inlet vane 35 is adjusted by the control unit so as to achieve a set temperature (for example, a cold water inlet temperature of 12 ° C. and a cold water outlet temperature of 7 ° C.).

  The low-pressure gas refrigerant sucked from the evaporator 7 is compressed by the turbo compressor 23 and compressed to an intermediate pressure. The gas refrigerant compressed to the intermediate pressure is cooled by the intermediate pressure gas refrigerant flowing from the intermediate pressure refrigerant pipe 27a. The gas refrigerant cooled by the intermediate pressure gas refrigerant is further compressed by the turbo compressor 23 to become a high pressure gas refrigerant.

The high-pressure gas refrigerant discharged from the turbo compressor 23 is led to the condenser 13 through the refrigerant pipe 39a.
In the condenser 13, the high-temperature and high-pressure gas refrigerant is cooled to substantially equal pressure by the cooling water from the cooling tower, and becomes a high-pressure and low-temperature liquid refrigerant. The high-pressure and low-temperature liquid refrigerant is led to the high-pressure expansion valve (first expansion valve 29) through the refrigerant pipe 39b, and is expanded to the intermediate pressure in an enthalpy manner by this high-pressure expansion valve. The refrigerant expanded to the intermediate pressure is led to the intermediate cooler 27 through the refrigerant pipe 39c. In the intermediate cooler 27, a part of the refrigerant evaporates and is led to the intermediate stage of the turbo compressor 23 through the intermediate pressure refrigerant pipe 27a. The liquid refrigerant that has been condensed without being evaporated in the intermediate cooler 27 is stored in the intermediate cooler 27. The intermediate-pressure liquid refrigerant stored in the intermediate cooler 27 is guided to the low-pressure expansion valve (second expansion valve 30) via the refrigerant pipe 39d. The intermediate-pressure liquid refrigerant is expanded to a low pressure in an enthalpy manner by a low-pressure expansion valve.
The refrigerant expanded to a low pressure evaporates in the evaporator 7 and takes heat from the cold water pipes 8a and 8b. Thereby, the cold water which flowed in at 12 ° C. is returned to the load side at 7 ° C.
The low-pressure gas refrigerant evaporated in the evaporator 7 is led to the low-pressure stage of the turbo compressor 23 and is compressed again.

Next, the operation panel 4 provided in each turbo refrigerator 3 will be described with reference to FIG. This figure shows only the configuration related to the present invention, and shows a block diagram when outputting an alarm signal, a trip signal, and a startup request signal.
The operation panel 4 includes a cold water inlet temperature (state variable) T0 obtained by the cold water inlet temperature sensor 31a (see FIG. 2) and a cold water outlet temperature (state variable) T1 obtained by the cold water outlet temperature sensor 31b (see FIG. 2). The condensation pressure (state variable) Pc obtained by the condenser pressure sensor 13s (see FIG. 2), the evaporation pressure (state variable) Pe obtained by the evaporator pressure sensor 7s (see FIG. 2), and the intercooler pressure. Intermediate pressure (state variable) Pm obtained by sensor 27s (see FIG. 2), lubricant temperature (state variable) Tp obtained by lubricant temperature sensor 23a (see FIG. 2), and ammeter 37a (see FIG. 2) Is input to the motor current (state variable) Am.

  The alarm signal output from the operation panel 4 is transmitted to the system control panel (see FIG. 1). This alarm signal is issued when the value from each sensor input to the operation panel 4 exceeds the first threshold value. The state in which the alarm signal is issued means that it is possible to return to the normal state while continuing the operation of the turbo chiller 3, and this point is different from the startup request signal.

  The trip signal output from the operation panel 4 is issued when the value from each sensor input to the operation panel 4 exceeds the second threshold value. The second threshold value is set to a value indicating an abnormal state higher than the first threshold value at which an alarm signal is issued. For example, in the case of the condensation pressure Pc, the second threshold value is set to a value larger than the first threshold value. When the trip signal is issued, the operation is immediately stopped to protect each device of the turbo refrigerator 3.

  The startup request signal output from the operation panel 4 is issued when the value from each sensor input to the operation panel 4 exceeds the third threshold value. The third threshold value is set between the first threshold value of the alarm signal and the second threshold value of the trip signal. The start-up request signal means a state in which the turbo chiller 3 is always stopped after a predetermined time (for example, 3 minutes). Therefore, when the third threshold value is exceeded, the operation stop prediction is performed. When a startup request signal is issued, the system control panel 2 that has received this signal controls the other turbo chillers 3 that are stopped to start.

  Next, the relationship between the alarm signal, trip signal, and startup request signal will be specifically described for each sensor value. In addition, about the cold water inlet temperature T0 and the cold water outlet temperature T1, since the alarm setting is not carried out, the description is abbreviate | omitted.

  Regarding the condensation pressure Pc, when the condensation pressure Pc increases and exceeds the first threshold, an alarm signal is issued. In this case, the operation of each of the expansion valves 29 and 30 (see FIG. 2) and the inlet vane 35 is limited and controlled so as to lead to normal operation. In spite of this, when the condensation pressure Pc further increases and exceeds the third threshold value, a startup request signal is issued. As a result, the start-up of the turbo chiller 3 as a subsequent machine is started, and the operating turbo chiller 3 is controlled to stop after a predetermined time. Even when this stop control is performed, when the condensation pressure Pc further increases and exceeds the second threshold value, a trip signal is issued and the turbo refrigerator 3 is forcibly stopped. In this case, even the turbo chiller 3 under stop control can be forcibly stopped without waiting for a predetermined time.

  As for the evaporation pressure Pe, an alarm signal is issued when the evaporation pressure Pe becomes low and exceeds the first threshold value. In this case, the operation of each of the expansion valves 29 and 30 (see FIG. 2) and the inlet vane 35 is limited and controlled so as to lead to normal operation. Nevertheless, when the evaporation pressure Pe further decreases and exceeds the third threshold value, a startup request signal is issued. As a result, the start-up of the turbo chiller 3 as a subsequent machine is started, and the operating turbo chiller 3 is controlled to stop after a predetermined time. Even when the stop control is performed, when the evaporation pressure Pe is further reduced and exceeds the second threshold value, a trip signal is generated and the turbo refrigerator 3 is forcibly stopped. In this case, even the turbo chiller 3 under stop control can be forcibly stopped without waiting for a predetermined time.

Regarding the lubricating oil temperature Tp, when the lubricating oil temperature Tp becomes high and exceeds the first threshold value on the high temperature side, an alarm signal is issued. However, this alarm signal is often issued when the control is not stable. Further, when the lubricating oil temperature Tp increases and exceeds the third threshold value, a startup request signal is issued. As a result, the start-up of the turbo chiller 3 as a subsequent machine is started, and the operating turbo chiller 3 is controlled to stop after a predetermined time. Even when this stop control is performed, when the lubricating oil temperature Tp further increases and exceeds the second threshold value, a trip signal is issued and the turbo refrigerator 3 is forcibly stopped. In this case, even the turbo chiller 3 under stop control can be forcibly stopped without waiting for a predetermined time.
Further, when the lubricating oil temperature Tp becomes low and exceeds the first threshold value on the low temperature side, an alarm signal is issued. However, this alarm signal is often issued when the control is not stable. Furthermore, when the lubricating oil temperature Tp becomes low and exceeds the third threshold value, a start-up request signal is issued. As a result, the start-up of the turbo chiller 3 as a subsequent machine is started, and the operating turbo chiller 3 is controlled to stop after a predetermined time. Even when this stop control is performed, when the lubricating oil temperature Tp is further lowered and exceeds the second threshold value, a trip signal is issued and the turbo refrigerator 3 is forcibly stopped. In this case, even the turbo chiller 3 under stop control can be forcibly stopped without waiting for a predetermined time.

  Regarding the motor current Am, when the motor current Am increases and exceeds the first threshold, an alarm signal is issued. In this case, the operation of each of the expansion valves 29 and 30 (see FIG. 2) and the inlet vane 35 is limited and controlled so as to lead to normal operation. Despite this, when the motor current Am further increases and exceeds the third threshold value, a startup request signal is issued. As a result, the start-up of the turbo chiller 3 as a subsequent machine is started, and the operating turbo chiller 3 is controlled to stop after a predetermined time. Even when the stop control is performed, when the motor current Am further increases and exceeds the second threshold value, a trip signal is generated and the turbo refrigerator 3 is forcibly stopped. In this case, even the turbo chiller 3 under stop control can be forcibly stopped without waiting for a predetermined time.

Next, control when the sensor is disconnected will be described.
Even if the sensor is disconnected, in a predetermined case, a start-up request signal is issued, and after the operation is continued for a predetermined time, the turbo chiller 3 is stopped. In this case, the operation stop prediction is performed when the sensor is disconnected. Specifically, even if the sensor is disconnected, if another sensor can obtain an alternative value, the alternative value is used to continue the operation for a predetermined time. Thereby, the starting time of the turbo chiller 3 which is a subsequent machine is securable.
Hereinafter, the setting of the substitute value for each sensor will be described.
(1) Cold water outlet temperature T1
If the cold water outlet temperature T1 cannot be obtained, an alternative value is obtained using the following equation.
T1 = ET (Pe) + Tde (LOAD)
Here, ET (Pe) is a saturation temperature at the evaporation pressure Pe, and Tde (LOAD) is a terminal temperature in the current refrigeration capacity LOAD, which means a temperature difference between the refrigerant temperature and the cold water temperature. The terminal temperature is determined in advance for each refrigeration capacity LOAD. However, when the refrigerating capacity is 100% or more, the refrigerating capacity is calculated as 100%.
In addition, in the case of warm water, it calculates | requires similarly using the condensation pressure Pc.
(2) Cold water inlet temperature T0
As shown in the following formula, assuming the rated capacity is output, the temperature difference at the specified rating is adopted.
T0 = T1 + ΔT (specification value)
When the cold water flow rate G is variable, the following equation is used.
T0 = T1 + ΔT · G (specification value) / G (current value)
In the case of warm water, it is obtained in the same manner as the above formula.
(3) Evaporation pressure Pe
Using the cold water outlet temperature T1, it calculates as the following formula.
Pe = P (T1-Tde (LOAD))
Here, the right side means a saturation pressure at a temperature indicating T1-Tde (LOAD).
(4) Intermediate pressure Pm
The intermediate pressure Pm is theoretically obtained from the following equation.
Pm = Pe · (Pc / Pe) ^0.5

Next, the operation method of the heat source system 1 will be described with reference to FIG.
The first turbo chiller 3 a and the second turbo chiller 3 b are activated by a command from the system control panel 2. In actual operation, one of the turbo chillers 3a and 3b is activated, and the other turbo chillers 3b and 3a are on standby in a stopped state for backup. Hereinafter, an operation method in which the first turbo chiller 3a is activated and the second turbo chiller 3b is used for backup will be described.

When a start command is applied from the system control panel 2 to the first turbo chiller 3a, it is determined that there is a start input (S1), and it is determined whether the light load is stopped (S2). At the same time, the operation of the heat medium (cold water) pump 12 (see FIG. 1) is started (S4).
If it is determined in step S2 that the light load is not stopped, it is determined whether or not activation is prohibited (S3). If it is not prohibited to start, it is determined whether the flow rate of the cold water and the cooling water is a predetermined flow rate (S5). At the same time, the operation of the cooling water pump 19 (see FIG. 1) is started (S6). If it is determined in step S5 that the flow rates of the cold water and the cooling water have been established, it is determined whether the start interlock has been established (S7). At the same time, the operation of the lubricating oil pump is started (S8). If it is determined in step S7 that the start interlock has been established, the electric motor 37 (see FIG. 2), which is the main motor, is started (S10). When the electric motor 37 is activated, it is determined that the activation is completed (S11), and after a predetermined time has elapsed in the timer (S12), the temperature adjustment control of the cold water temperature is started (S13). The temperature adjustment control is continued unless a stop signal is input (S14). When a stop signal is input in step S14, a stop flow of the first turbo chiller 3a is performed (S15).

  On the other hand, when the electric motor 37 is started in step S10, alarm monitoring (S18), trip monitoring (S20), and startup request monitoring (S21) are performed.

  In the alarm monitoring (S18), when an alarm signal is issued, an alarm warning display (S19) is performed.

  In trip monitoring (S20), when a trip signal is issued, trip stop, that is, the first turbo chiller 3a is immediately stopped (S23). When the trip is stopped and the reset button is pressed down (S24), the first turbo chiller 3a stands by in a stopped state.

In the startup request monitoring (S21), when the output value from each sensor exceeds the third threshold or when a predetermined sensor is disconnected, a request signal (S25) is sent to the system control panel 2 when a startup request signal is issued. Based on this signal, the system control panel 2 sends an activation command to the stopped second turbo chiller 3b to activate the second turbo chiller 3b.
When a startup request signal is issued, a trip stop (S20) is performed after a predetermined time (for example, 3 minutes) has elapsed in the timer (S22).

According to this embodiment, the following effects can be obtained.
Based on the state of each sensor, when an operation stop prediction that is predicted to be stopped after a predetermined time elapses is performed, a start-up request signal for starting another turbo chiller 3b is issued, thereby operating The other centrifugal chiller 3b can be started before the other centrifugal chiller 3a stops. Accordingly, since the operating centrifugal chiller 3a issues a startup request signal and stops after a predetermined time has elapsed, this predetermined time can be used as the startup time of the other turbo chiller 3b that is the subsequent machine. . Even if the turbo chiller 3a is stopped after a predetermined time has elapsed, since the start of the turbo chiller 3b, which is a subsequent machine, has already started, the chilled water supplied to the external load exhibits a significant temperature fluctuation. There is no.
In addition, since the start-up request signal is used as a value between the alarm signal and the trip signal, it is possible to realize the operation that can be stopped for a predetermined time although it is stopped reliably. As compared with the case of starting the vehicle, it is possible to avoid unnecessary starting of the subsequent machine.
In addition, when an abnormality occurs in a sensor that measures various states of the centrifugal chiller 3 (for example, disconnection) and the sensor is an important sensor for continuing the operation, the operation is generally stopped immediately. However, since an alternative value is obtained by another sensor and the operation is continued for a predetermined time using the alternative value, it is possible to secure the start-up time of the turbo chiller 3b that is the subsequent machine.

In the present embodiment, the turbo chiller 3 has been described as an example of the heat source machine. However, other heat source machines may be used. For example, a screw chiller may be used instead of the turbo chiller 3.
Further, although the cooling operation has been described in the present embodiment, the present invention can be similarly applied to a heat pump heating operation.
Moreover, although the heat source system 1 having two turbo chillers 3 has been described as an example, the number of heat source units may be three or more.
The operation panel 4 that issues a startup request signal is preferably provided in all the turbo chillers 3a and 3b, but may be provided in either one.
Alternatively, a temperature sensor may be installed in the housing of the electric motor 37 to measure the motor temperature, and a startup request signal may be issued based on the motor temperature.

1 is a schematic configuration diagram showing a heat source system according to an embodiment of the present invention. It is the schematic block diagram which showed the turbo refrigerator of FIG. It is a block diagram showing a part function of the operation panel provided in the turbo refrigerator. It is the flowchart which showed operation | movement of the heat-source system.

Explanation of symbols

1 Heat source system 2 System control panel 3 Turbo refrigerator (heat source machine)
4 Operation panel (heat source machine control device)

Claims (7)

A control device for a heat source device that controls the heat source device by monitoring the state of the heat source device that cools or heats the heat medium flowing from the external load and supplies the heat medium to the external load,
When an operation stop prediction is made that the operation of the heat source unit is predicted to stop after a predetermined time due to an abnormality in the state of the heat source unit, a late start signal for requesting start of another heat source unit is issued. A control device for a heat source machine. Each state variable indicating various states of the heat source unit is monitored, and when the state variable exceeds a first threshold value, an alarm signal is issued and the operation is continued to return to a normal operation state. If it exceeds the first threshold and further exceeds the second threshold, it is determined that the operation cannot be continued and the heat source machine is abnormally stopped,
The heat source apparatus according to claim 1, wherein the operation stop prediction is performed when the state variable exceeds a third threshold value set between the first threshold value and the second threshold value. Control device. When an abnormality occurs in a sensor that measures various states of the heat source machine, the operation stop prediction is performed,
The control device for a heat source unit according to claim 1, wherein the operation of the heat source unit is continued for the predetermined time by an alternative value using another sensor.   4. The control device for a heat source unit according to claim 1, wherein the predetermined time is a time at which the other heat source unit to which the starter start signal is given is substantially completed in startup. 5. .   A heat source machine comprising the heat source machine control device according to claim 1. A plurality of heat source units that cool or heat the heat medium flowing from the external load and supply the heat medium to the external load;
A system controller for controlling each of the heat source units, and a heat source system comprising:
At least one of the heat source units includes the heat source unit control device according to any one of claims 1 to 4,
The said system control apparatus starts the said other heat source machine by the late generator starting signal emitted from the control apparatus of the said heat source machine, The heat source system characterized by the above-mentioned. A method for controlling a heat source device, wherein the state of a heat source device that cools or heats a heat medium flowing from an external load and supplies the heat medium to the external load is monitored, and the heat source device is controlled.
When an operation stop prediction is made that the operation of the heat source unit is predicted to stop after a predetermined time due to an abnormality in the state of the heat source unit, a late start signal for requesting start of another heat source unit is issued. A control method for a heat source machine.

Images