JP5907851B2 - Emergency power generation system - Google Patents

Description

The present invention includes a plurality of power generators capable of supplying power generated at a reference voltage and a reference frequency to a power load;
A power failure detection means for detecting a power failure that stops receiving power from the commercial power system;
At the time of a power failure in which a power failure is detected by the power failure detection means, a general power load excluding the specific power load among the power loads is disconnected from the plurality of power generation devices, and the generated power of the plurality of power generation devices is the specific power. Power disconnection means to supply only to the load,
In the event of a power failure in which a power failure is detected by the power failure detection means, a power failure power generation output control is performed to control the power generation output of the plurality of power generation devices after executing a power failure start process for starting the plurality of power generation devices. Then, the present invention relates to an emergency power generation system provided with power generation output control means for supplying power generated by the plurality of power generation devices to the specific power load.

  In a facility provided with a power load such as an electric device, received power of a reference voltage (for example, 200 V) and a reference frequency (for example, 60 Hz) received from a normal commercial power system is supplied to the power load. In addition, such a facility may be provided with a power generation device capable of generating power in connection with, for example, a commercial power system and supplying generated power of a reference voltage and a reference frequency to an electric load.

In a facility equipped with such a power generation device, even when a power failure occurs when receiving power from the commercial power system is stopped, the power generated by the power generation device is supplied to only a specific power load to supply power to the specific power load. In order to continue the operation, there is a case where an emergency power generation system configured to execute power generation output control at the time of power failure for controlling the power generation output of the power generation device is provided (see, for example, Patent Document 1).
In an emergency power generation system, in order to stably supply power to a specific power load even in the event of a power failure, the power generation capacity of the power generation device installed in the facility can Will be decided accordingly. In particular, in business establishments where the power consumption of a specific power load is large, a relatively large power generation capability is required, and thus a plurality of power generation devices may be installed.

  The emergency power generation system as described above usually employs a storage battery or the like that can be activated independently even during a power failure without power supply from an external power source such as a commercial power system.

JP 2001-212570 A

Since the power generator capable of self-starting is equipped with a storage battery, it is relatively expensive. Therefore, in the emergency power generation system as described above, when a plurality of power generation devices are installed in order to cover the power consumption of a relatively large specific power load, there is a problem that the equipment cost increases.
Therefore, it is conceivable to start up all the power generation devices with the stored power of the storage battery by providing a storage battery separately from the power generation device, but relatively large power is required to start all the power generation devices in the event of a power failure Therefore, even in this case, it is necessary to provide an expensive storage battery having a relatively large capacity.
In addition, when a plurality of power generators are installed and operated simultaneously, in order to appropriately follow the power generation output of the plurality of power generators against fluctuations in the power consumption of the specific power load, Appropriate control is required.

  The present invention has been made paying attention to such a point, and its purpose is to supply power to the specific power load by supplying the power generated by a plurality of power generators only to some specific power loads at the time of a power failure. In an emergency power generation system to be continued, the power generation output of each power generation device is controlled so that the power generation output of a plurality of power generation devices can appropriately follow fluctuations in power consumption of a specific power load while suppressing the equipment cost as much as possible. It is to provide the technology to obtain.

To achieve this object, an emergency power generation system according to the present invention includes:
A plurality of power generators capable of supplying a power load with power generated at a reference voltage and a reference frequency;
A power failure detection means for detecting a power failure that stops receiving power from the commercial power system;
At the time of a power failure in which a power failure is detected by the power failure detection means, a general power load excluding the specific power load among the power loads is disconnected from the plurality of power generation devices, and the generated power of the plurality of power generation devices is the specific power. Power disconnection means to supply only to the load,
In the event of a power failure in which a power failure is detected by the power failure detection means, a power failure power generation output control is performed to control the power generation output of the plurality of power generation devices after executing a power failure start process for starting the plurality of power generation devices. An emergency power generation system including a power generation output control means for supplying the generated power of the plurality of power generation devices to the specific power load,
The first characteristic configuration is
As the plurality of power generation devices, a first power generation device that can be activated independently, and a second power generation device that can be activated using electric power supplied from the outside,
The power generation output control means activates the second power generation device using the generated power of the first power generation device after the first power generation device is activated independently in the power failure start processing, and starts the power generation In the power generation output control at the time of power failure, the power generation output of the second power generation device is controlled so that the actual power generation output of the first power generation device becomes a predetermined set power generation output after executing the processing.

According to the first characteristic configuration, a part of the first power generation devices among the plurality of power generation devices employs a relatively expensive first power generation device that is mounted with a storage battery or the like and is configured to be able to start independently. However, the other second power generation device employs a relatively inexpensive second power generation device that is configured to be able to start using the generated power of the first power generation device without the need to mount a storage battery or the like. Compared with the case where all of the power generators are power generators that can be activated independently, the equipment cost can be suppressed as much as possible.
Further, even when such a first power generation device and a second power generation device are employed, after the first power generation device is independently activated in the power failure output control means by the power generation output control means, the first power generation is performed. By starting the second power generation device using the power generated by the device, all of the plurality of power generation devices can be appropriately started.
Then, the power generation output control means executes the power failure start-up process, and then performs the power failure power generation output control to link the second power generation device to the first power generation device. The actual power output of the first power generator is maintained at the predetermined set power output, and the power output of the second power generator compensates for the amount of power consumption of the specific power load minus the set power output of the first power generator. Controlled in form. Therefore, the power generation outputs of the plurality of power generation devices appropriately follow the fluctuations in the power consumption of the specific power load.
Therefore, according to the present invention, it is possible to control the power generation output of each power generation device so that the power generation output of a plurality of power generation devices can appropriately follow fluctuations in power consumption of a specific power load while suppressing the equipment cost as much as possible. Power generation system can be realized.

In addition to the first feature configuration, the second feature configuration of the emergency power generation system according to the present invention includes:
A plurality of the second power generation devices are provided,
The power generation output control means is that the plurality of second power generation devices are sequentially activated after the first power generation device is independently activated in the power failure start-up process.

  According to the second characteristic configuration, in the case where a plurality of second power generation devices that are activated by the generated power of the first power generation device are provided, the first power generation device is activated independently in the power failure output control process by the power generation output control means. By sequentially starting the plurality of second power generation devices after that, it is possible to avoid an instantaneously excessive power load for starting the second power generation device that is input to the first power generation device. For example, it is possible to prevent a stall or the like due to an overload of the driving engine of the first power generator.

The third characteristic configuration of the emergency power generation system according to the present invention is in addition to any of the first to second characteristic configurations,
The first power generator is configured to perform power generation voltage control for adjusting a power generation output so as to maintain an output voltage at the reference voltage;
In the power generation output control at the time of power failure, the power generation output control means sets the set power generation output of the first power generation device to a predetermined set partial power generation output smaller than the rated power generation output of the first power generation device.

According to the third characteristic configuration, the first power generation device is configured to execute the power generation voltage control for adjusting the power generation output so as to maintain the output voltage at the reference voltage. In executing power generation output control at the time of a power failure, if the power consumption of the specific power load fluctuates suddenly due to the interruption of the specific power load, the first power generation output of the second power generator is changed prior to the first power output. The power generation device changes the power generation output in accordance with fluctuations in power consumption so as to maintain the reference voltage.
On the other hand, when the power consumption of the specific power load changes slowly, the first power generator attempts to change the power generation output to maintain the reference voltage, and at the same time, the second power generator The actual power generation output is maintained at a predetermined set power generation output, and as a result, the second power generation device changes the power generation output in accordance with the fluctuation of the power consumption. That is, by performing such power generation output control during a power failure, the power generation outputs of the first power generation device and the second power generation device appropriately follow fluctuations in power consumption.

  In the power generation output control at the time of power outage, the set power generation output of the first power generator is not set to the rated power generation output, but is set to a partial power generation output of about 50%. It is possible to appropriately suppress an increase in the actual power generation output of one power generation device and maintain the power generation output of the grid power generation device within an appropriate range. Furthermore, the actual power generation output of the first power generation device is always maintained to be equal to or greater than the partial power generation output, and the adjustment range on the lower side is always secured in the actual power generation output of the first power generation device. As a result, even when a sudden and significant reduction in power consumption occurs due to the interruption of the specific power load, the actual power generation output of the first power generation device can be drastically and greatly reduced, resulting in a plurality of power generation devices. This power generation output can be made to follow the fluctuation of the power consumption of the specific power load appropriately.

Furthermore, the period when the power consumption of the specific power load reaches a partial power generation output of the first power generation device is relatively low, and the power generation output of the second power generation device reaches the rated power generation output of the second power generation device. During the period when the power consumption is relatively large, the power generation output of the second power generation device is fixed at 0 or the rated power generation output, and therefore the power generation output of the first power generation device is adjusted by power generation voltage control. Become.
Note that even during the period when the power generation output of the second power generation device is 0, the start-up of the second power generation device is completed, and the idling state in which power generation is stopped due to the disconnection state from the specific power load.

The fourth characteristic configuration of the emergency power generation system according to the present invention is in addition to any of the first to third characteristic configurations described above,
A difference signal output means for outputting a power generation output difference signal corresponding to a difference between an actual power generation output and the set power generation output of the first power generation device;
The power generation output control means controls the power generation output of the second power generation device so that the power generation output difference signal output from the difference signal output means is constant in the power generation output control during the power failure.

  According to the fourth characteristic configuration, the power generation output difference signal is a signal corresponding to a difference between the actual power generation output and the set power generation output of the first power generation device. In the output control, the power generation output of the second power generator is determined and controlled so that the power generation output difference signal recognizes the excess or deficiency of the actual power generation output with respect to the set power output of the first power generator and eliminates the excess or deficiency. can do.

The fifth characteristic configuration of the emergency power generation system according to the present invention is in addition to the fourth characteristic configuration described above,
There is a limiter for limiting the power generation output difference signal to a set lower limit value or more.

  According to the fifth characteristic configuration, the power generation output difference signal input to the power generation output control means is, for example, an actual power generation output of the first power generation device due to a load interruption that occurs suddenly and drastically reduces power consumption. Even when the power generation output difference signal is drastically reduced due to a sudden and drastic decrease, the power generation output difference signal is always limited to the set lower limit value or more by the limiter. Therefore, in the power generation output control at the time of power failure by the power generation output control means, it is avoided that the input power generation output difference signal deviates below the controllable range of the power generation output of the second power generation device. Stoppage of power generation can be prevented.

Configuration diagram of emergency power generation system The graph which shows transition of the power generation output of each power generator with respect to power consumption

An embodiment of an emergency power generation system according to the present invention will be described with reference to the drawings.
The emergency power generation system shown in FIG. 1 is provided in a facility such as a business establishment having a power load A that consumes the received power received from the commercial power system 1, and a power failure that stops receiving power from the commercial power system 1 occurs. When generated, the system is configured as a system that supplies the generated power generated by the power generator B to the specific power load 8 of the power load A.
The received power received from the commercial power system 1 is supplied to the power line 2 and supplied to the general power load 4 excluding the specific power load 8 connected to the power line 2. Also, the received power supplied to the power line 2 is supplied to the power line 6 via the switch 5 described later, and is supplied to the specific power load 8 connected to the power line 6.

Such an emergency power generation system is provided with a plurality of power generation devices B described below.
The plurality of power generators B are configured to be able to supply the power load A with generated power having the same reference voltage (for example, 200 V) and reference frequency (for example, 60 Hz) as the received power of the commercial power system 1. Furthermore, in the emergency power generation system of the present embodiment, as the plurality of power generation devices B, the self-sustained power generation device 20 as the first power generation device capable of self-sustained activation and the first power generation device that can be activated using the power supplied from the outside. A grid-connected power generation device 30 as two power generation devices is provided.

In the emergency power generation system of the present embodiment, the number of power generation devices B is determined in accordance with the maximum power consumption of the specific power load 8 or the like.
Specifically, two independent power generation devices 20 and four interconnection power generation devices 30 as a plurality of interconnection power generation devices 30 are arranged in parallel.
In addition, the number of each electric power generating apparatus B can be changed suitably.

The power generator B is configured as a general power generator that generates power in such a manner that the synchronous generators 21 and 31 are driven by the engines 22 and 32, and the generated power of the synchronous generators 21 and 31 is used as a reference voltage and a reference. There are provided power conversion units 25 and 35 for converting the frequency, and control units 26 and 36 for controlling the outputs of the engines 22 and 32 in such a manner that the number of rotations of the engines 22 and 32 is set to a desired set number of rotations. .
The power converters 25 and 35 convert the AC voltage at the output end of the synchronous generators 21 and 31 into a DC voltage, and convert the DC voltage output from the converters 25b and 35b into an AC voltage. And output inverters 25a and 35a. The converters 25b and 35b and the inverters 25a and 35a are both configured to be capable of bidirectional voltage conversion.
Further, the control unit 26 of the self-sustained power generation apparatus 20 is configured to execute power generation voltage control for adjusting the power generation output so that the output voltage output from the power conversion unit 25 is maintained at the reference voltage.

The motors 22 and 32 are provided with cell motors 23 and 33 for starting the engines 22 and 32 in response to commands from the control units 26 and 36, respectively.
The self-sustained power generation apparatus 20 is configured to be capable of self-sustained activation in a form in which the cell motor 23 is operated by supplying the power stored in the battery 28 built in the cell motor 23 even when there is no external power supply. . Although not shown, the battery 28 is configured to store in advance the power taken from the power output side.
On the other hand, the interconnection power generation apparatus 30 is provided with a power supply circuit 34 that takes in DC power from the DC line of the power conversion unit 35, and supplies the power taken in by the power supply circuit 34 to the cell motor 33 to operate the cell motor 33. It is comprised so that starting is possible.

The emergency power generation system further detects a power outage that stops receiving power from the commercial power system 1 by referring to the measurement result of the power measuring instrument 12 that measures the received power received by the power line 2 from the commercial power system 1. In addition to the power failure detection means E, the general power load 4 is disconnected from the plurality of power generation devices B at the time of the power failure detected by the power failure detection means E, and the generated power of the plurality of power generation devices B is specified power load. 8 is provided in order to supply only to 8 when power is interrupted.
Furthermore, after executing a power failure start process for starting a plurality of power generators B when a power failure is detected by the power failure detection means E, the power generation outputs of the plurality of power generators B are controlled, A power generation output control means C that supplies the generated power of the power generation apparatus B to the specific power load 8 is provided. The power failure detection means E, power failure disconnection means D, and power generation output control means C are configured so that the control device 50 including a computer or the like functions when a predetermined program is executed.

This power disconnection means D disconnects the general power load 4 from the plurality of power generators B by switching the state of the switch 5 described below.
The switch 5 is provided between the power line 2 to which the commercial power system 1 and the general power load 4 are connected and the power line 6 to which the specific power load 8 is connected. Specifically, the switch 5 is configured by a transfer contact type switch (switched by voltage ON / OFF), and the commercial power system 1 and the general power load 4 are connected to the switch 5. The power line 2 is connected to the normally open contact 5a, the power output side of the self-sustaining power generator 20 is connected to the normally open contact 5a and the normally closed contact 5b, and the power line 6 to which the specific power load 8 is connected is connected to the common contact 5c. Yes. On the other hand, the power output side of the grid power generation apparatus 30 is connected to the power line 6 to which the specific power load 8 is connected.
That is, by setting the switch 5 to an ON state (a state where the common contact 5c is connected to the normally open contact 5a), the commercial power system 1, the power line 2, and the power line 6 are connected, and a plurality of power generators B Is connected to these power lines 2 and 6, the received power received from the commercial power system 1 and the generated power generated by the plurality of power generators 20 and 30 can be supplied to all the power loads A. become able to.
On the other hand, by setting the switch 5 to an OFF state (a state in which the common contact 5c is connected to the normally closed contact 5b), the power line 6 is maintained while the connection on the power output side of the plurality of power generators B to the power line 6 is maintained. Since the power line 2 is disconnected, the generated power generated by the plurality of power generation devices 20 and 30 can be supplied only to the specific power load 8.
Therefore, when the power failure is detected by the power failure detection means E, the power disconnection means D switches the switching device 5 from the ON state to the OFF state so that the general power load 4 is changed to a plurality of power generators B. The power generated by the plurality of power generators B can be supplied to only the specific power load 8 by disconnecting from the power generator B.

On the common contact 5c side of the switch 5 of the power line 6 to which the specific power load 8 is connected, a power measuring device 13 for measuring the received power received by the power line 6 is provided. When the power failure occurs, the switch 5 is turned off and the common contact 5c to which the power line 6 is connected becomes the normally closed contact 5b to which the power output side of the independent power generator 20 is connected. If connected, the power meter 13 measures the power supplied to the power line 6 from the self-sustained power generation apparatus 20, that is, the actual power generation output P2 of the entire self-sustained power generation apparatus 20, and outputs a signal corresponding to the power generation output. Will do.
The power measuring instrument 12 that measures the received power of the power line 2 and the power measuring instrument 13 that measures the power generation output of the self-sustained power generation apparatus 20 at the time of a power outage are received power in the range of 0 to 160 kW which is the full scale of the inverter Accordingly, the analog signals S1 and S2 within the range of 4 mA to 20 mA are output.
Specifically, the analog signal S1 output from the power meter 12 and the analog signal S2 output from the power meter 13 are set so as to have a magnitude determined by the following equations (1) and (2). Yes.

S1 = 4 (mA) +0.1 (mA / kW) × P1 (1)
S2 = 4 (mA) +0.1 (mA / kW) × P2 (2)
P1: Power received from the commercial power system 1 at normal time (kW)
P2: Actual power generation output (kW) of the entire self-sustaining power generation device 20 at the time of a power failure

In addition, the analog signal S2 output from the power measuring device 13 that measures the actual power generation output P2 of the entire independent power generation apparatus 20 at the time of a power failure is input to the subtractor 15 and the predetermined analog signal output from the analog signal generator 14 is output. S3 is subtracted.
The analog signal generator 14 receives the set power generation output P2a of the entire self-sustained power generation apparatus 20 from the power generation output control means C, and outputs an analog signal S3 within a range of 4 mA to 20 mA according to the set power generation output P2a. Is configured to do.
That is, the analog signal S4 output from the subtracter 15 takes a value corresponding to the difference between the actual power generation output P2 and the set power generation output P2a of the entire independent power generation apparatus 20, and the actual power generation output P2 is set. When it coincides with the power generation output P2a, it takes a constant value.
That is, the subtractor 15 functions as difference signal output means F that outputs an analog signal S4 corresponding to the difference of the actual power generation output P2 with respect to the set power generation output P2a of the entire self-sustained power generation apparatus 20 as a power generation output difference signal. Become.
Specifically, the magnitudes of the analog signal S3 output from the analog signal generator 14 and the analog signal S4 output from the subtractor 15 are determined by the following equations (3) and (4).

S3 = 4 (mA) +0.1 (mA / kW) × (P2a−1.6 (kW)) (3)
S4 = S2- (S3-4 (mA))
= 4.16 (mA) + 0.1 (mA / kW) x (P2-P2a) (4)
P2a: Set power generation output (kW) of the self-sustained power generation device 20 as a whole

According to the difference between the analog signal S1 that takes a value corresponding to the received power of the power line 2 output by the power meter 12 and the actual power output P2 with respect to the set power output P2a of the entire self-sustained power generation device 20 output by the subtractor 15 The analog signal S4 that takes a value is selectively switched by the switch 16 and input to the grid power generation apparatus 30.
Specifically, the switch 16 is composed of a transfer contact type switch (switched by voltage ON / OFF). In the switching device 16, the analog signal S1 is input to the normally open contact 16a, while the analog signal S4 is input to the normally closed contact 16b, and any one of the analog signals S1 and S2 output from the common contact 16c. One of them is input to the control unit 36 of the grid power generation apparatus 30.

Further, the switch 16 is switched from the ON state to the OFF state by the power generation output control means C when a power failure is detected by the power failure detection means E.
That is, when the power reception from the commercial power system 1 is normally performed, the switch 16 is turned on (a state in which the common contact 16c is connected to the normally open contact 16a), and according to the power received by the power line 2. On the other hand, the switch 16 is in an OFF state (the common contact 16c is a normally closed contact) at the time of a power failure in which the power reception from the commercial power system 1 is stopped. 16b), an analog signal S4 having a value corresponding to the difference between the actual power generation output P2 and the set power generation output P2a of the entire independent power generation apparatus 20 is input to the control unit 36 of the grid power generation apparatus 30. Will be.

And the control part 36 of the interconnection power generator 30 sets the rotation speed of the engine 32 so that the input analog signals S1 and S4 are maintained at a constant value of 4.16 mA, so that the interconnection power generator 30 power generation outputs are controlled.
Therefore, at the normal time, the analog signal S1 output from the power meter 12 is maintained at a constant value of 4.16 mA, in other words, the received power of the power line 2 is maintained at 1.6 kW corresponding to the constant value. The power generation output P3 of the entire grid power generation apparatus 30 is controlled.
On the other hand, at the time of a power failure, the analog signal S4 output from the subtractor 15 is maintained at a constant value of 4.16 mA. In other words, the actual power generation output P2 of the entire self-sustained power generation apparatus 20 is maintained in accordance with the set power generation output P2a. As described above, the power generation output P3 of the entire grid power generation apparatus 30 is controlled.
As described above, when the power generation output control means C inputs the set power generation output P2a of the entire independent power generation apparatus 20 to the analog signal generator 14 at the time of a power failure, the actual power generation of the entire independent power generation apparatus 20 is performed. Controlling the power generation output P3 of the entire grid power generation apparatus 30 so that the output P2 becomes a predetermined set power generation output P2a is referred to as power generation output control during a power failure.
The set power generation output P2a of the self-sustained power generation apparatus 20 as a whole is set to a predetermined partial power generation output smaller than the rated power generation output of the self-sustained power generation apparatus 20, and a vertical adjustment range of the power generation output of the self-sustained power generation apparatus 20 is ensured. ing.

  Further, in such power generation output control during a power failure, for example, during a power failure, a load interruption accompanied by, for example, a rapid and significant reduction in power consumption Q occurs, and the actual power generation output P2 of the entire self-sustained power generation device 20 suddenly and significantly When the voltage is lowered, the difference between the actual power generation output P2 and the set power generation output P2a of the entire self-sustained power generation apparatus 20 suddenly and greatly decreases, so that the analog signal S4 output from the subtractor 15 has a set lower limit of 4 mA May fall below. When this analog signal S4 is directly input to the control unit 36 of the grid power generation apparatus 30, the control unit 36 erroneously recognizes that all the specific power loads 8 have been disconnected, resulting in an abnormal stop of the engine 32. There is concern.

Further, a limiter 17 is provided on the common contact 16c side of the switch 16 to limit the analog signals S1 and S4 input to the control unit 36 of the grid power generation apparatus 30 to a set lower limit value (for example, 4 mA) or more. . That is, the limiter 17 always maintains the analog signals S1 and S4 input to the control unit 36 of the grid power generation apparatus 30 at or above the set lower limit value.
Therefore, even when the analog signal S4 output from the subtractor 15 falls below the set lower limit during a power failure, the analog signal S4 ′ input to the control unit 36 of the grid power generation apparatus 30 by the limiter 17 is Therefore, the controller 36 keeps the input 4 mA analog signal S4 ′ at a constant value of 4.16 mA so that the rotational speed of the engine 32 is relatively small. Since the reduction in power generation output is limited by reducing the scale, abnormal stop of the engine 32 can be avoided.
Note that when the actual power generation output P2 of the entire self-sustained power generation apparatus 20 is suddenly and significantly reduced due to a sudden and significant decrease in the power consumption Q in this way, the power generation of the entire grid power generation apparatus 30 is performed. When the decrease in the output P3 is restricted, there is a concern that the current flows backward from the grid power generation device 30 to the self-sustained power generation device 20 via the power line 6. Therefore, a protection device 29 for preventing the backflow of the current is provided on the output side of the generated power of the self-supporting power generation device 20.

The details of the processing flow executed by each means at the time of a power failure in which a power failure is detected by the power failure detection means E will be described with reference to the graph shown in FIG.
The graph shown in FIG. 2 shows the transition of the power generation output of each of the self-sustained power generation apparatus 20 and the interconnected power generation apparatus 30 that are output in accordance with the transition of the power consumption Q of the specific power load 8 at the time of a power failure. ing.

First, when a power failure is detected by the power failure detection means E at the timing indicated by time t0 in FIG. 2, the switch 5 is switched from the ON state to the OFF state by the power failure disconnecting means D, and the general power load 4 is The power generators B are disconnected from each other.
Thereafter, the power generation output control means C activates the plurality of power generation devices B in a no-load state where no power load is applied to each power generation device B as shown at time t0 to time t1 in FIG. Start-up processing is executed.
In the start-up process at the time of a power failure, first, the self-sustained power generation apparatus 20 is activated independently, and then the power generated by the self-sustained power generation apparatus 20 is supplied to the grid power generation apparatus 30 via the power line 6. The grid-connected power generator 30 is activated using 20 generated power.
Furthermore, in the start-up process at the time of a power failure, when starting the grid power generation apparatus 30, the four grid power generation apparatuses 30 are sequentially activated instead of simultaneously starting the four grid power generation apparatuses 30. Thus, it is avoided that the power load for starting up the grid power generation device 30 input to the self-sustained power generation device 20 is excessively large.

In the event of a power failure, the power generation output control means C executes the power failure start process to start the plurality of power generators B, and then performs power failure output control.
In the power generation output control at the time of power failure, as described above, the partial power generation output (for example, 33 kW) corresponding to about 50% of the rated power generation power (for example, 70 kW) with respect to the analog signal generator 14 in each of the independent power generation devices 20. By inputting the set power generation output P2a set to, the control unit 36 of the grid power generation device 30 connects the interconnection so that the actual power generation output P2 of the entire independent power generation device 20 becomes the predetermined set power generation output P2a. The power generation output P3 of the entire power generation device 30 is controlled.

  The period until the power consumption Q of the specific power load 8 input to the power generation apparatus B reaches the set power generation output P2a (33 kW) of the entire independent power generation apparatus 20 is the period from time t1 to time t2 in FIG. As shown, the grid power generation device 30 is disconnected from the specific power load 8 and is in an idling state where power generation is stopped, and the power consumption Q of the specific power load 8 is covered only by the independent power generation device 20. That is, in the self-sustained power generation apparatus 20, the control unit 26 controls the output of the engine 22 in such a manner that the output voltage is maintained at the reference voltage, so that the actual power generation output P2 of the entire self-sustained power generation apparatus 20 becomes the specific power load 8 It corresponds to the power consumption Q.

Next, when the power consumption Q of the specific power load 8 exceeds the partial power generation output (33 kW), the power generation during the power failure is performed with the set power generation output P2a of the entire self-sustained power generation apparatus 20 set to the partial power generation output. Output control is executed.
Then, as shown in the period of time t2 to time t3 in FIG. 2, the actual power generation output P2 of the entire independent power generation apparatus 20 is maintained at the set power generation output P2a, and the power generation output P3 of the entire grid power generation apparatus 30 is specified. Control is performed in such a manner as to compensate for the amount of power consumption Q of the power load 8 subtracted from the set power generation output P2a of the entire independent power generation device 20.

Furthermore, as shown in the period after time t3 in FIG. 2, the power generation output P3 of the plurality of interconnection power generation apparatuses 30 as a whole reaches the rated power generation output P3a (140 kW) of the plurality of interconnection generation apparatuses 30 as a whole. During the period, since the power generation output P3 of the entire grid power generation device 30 cannot increase beyond the rated power generation output P3a, the control unit 26 of the self-sustained power generation device 20 generates power so as to maintain the output voltage at the reference voltage. In the form that adjusts the output P2, the actual power generation output P2 of the entire independent power generation apparatus 20 compensates for the subtraction of the rated power generation output P3a of the entire grid power generation apparatus 30 from the power consumption Q of the specific power load 8. Will be controlled.
As shown at time t4 in FIG. 2, even when the power consumption Q of the specific power load 8 is suddenly and greatly reduced due to load interruption or the like, the control unit 26 of the independent power generator 20 sets the output voltage to the reference voltage. As a result, the power generation output P2 is suddenly and significantly reduced so as to maintain the power.

Further, when the power consumption Q of the specific power load 8 is reduced to a state where the power generation output P3 of the entire grid power generation device 30 can be suppressed to the rated power generation output P3a or less, it is the same as the period from the time t2 to the time t3 described above. The actual power generation output P2 of the entire independent power generation device 20 is maintained at the set power generation output P2a, and the power generation output P3 of the entire grid power generation device 30 is changed from the power consumption Q of the specific power load 8 to the set power generation output of the self-sustained power generation device 20. It will be controlled in a form that compensates for the subtraction of p2a.
In this embodiment, the range of the received power (0 to 160 kW), the range of the analog signal S output from the power meter 13 and the analog signal generator 14 (4 mA to 20 mA), the engine 32 in the interconnection power generation apparatus 30 Various numerical values cited as the target values (4.16 mA) of the analog signals S1 and S4 input for setting the rotational speed do not limit the present invention, and numerical values that can be set according to the implementation situation as appropriate. It is.

The present invention includes a plurality of power generators capable of supplying power generated at a reference voltage and a reference frequency to a power load;
A power failure detection means for detecting a power failure that stops receiving power from the commercial power system;
At the time of a power failure in which a power failure is detected by the power failure detection means, a general power load excluding the specific power load among the power loads is disconnected from the plurality of power generation devices, and the generated power of the plurality of power generation devices is the specific power. Power disconnection means to supply only to the load,
In the event of a power failure in which a power failure is detected by the power failure detection means, a power failure power generation output control is performed to control the power generation output of the plurality of power generation devices after executing a power failure start process for starting the plurality of power generation devices. Thus, it can be suitably used as an emergency power generation system including power generation output control means for supplying power generated by the plurality of power generation devices to the specific power load.

1: Commercial power system 4: General power load 8: Specific power load 15: Subtractor 17: Limiter 20: Stand-alone power generator (first power generator)
30: Interconnection power generator (second power generator)
A: Power load B: Power generation device C: Power generation output control means D: Power outage disconnecting means E: Power outage detection means F: Difference signal output means

Claims (5)

A plurality of power generators capable of supplying a power load with power generated at a reference voltage and a reference frequency;
A power failure detection means for detecting a power failure that stops receiving power from the commercial power system;
At the time of a power failure in which a power failure is detected by the power failure detection means, a general power load excluding the specific power load among the power loads is disconnected from the plurality of power generation devices, and the generated power of the plurality of power generation devices is the specific power. Power disconnection means to supply only to the load,
In the event of a power failure in which a power failure is detected by the power failure detection means, a power failure power generation output control is performed to control the power generation output of the plurality of power generation devices after executing a power failure start process for starting the plurality of power generation devices. An emergency power generation system including a power generation output control means for supplying the generated power of the plurality of power generation devices to the specific power load,
As the plurality of power generation devices, a first power generation device that can be activated independently, and a second power generation device that can be activated using electric power supplied from the outside,
The power generation output control means activates the second power generation device using the generated power of the first power generation device after the first power generation device is activated independently in the power failure start processing, and starts the power generation An emergency power generation system that controls the power generation output of the second power generation device so that the actual power generation output of the first power generation device becomes a predetermined set power generation output in the power generation output control at the time of power failure after executing the processing . A plurality of the second power generation devices are provided,
2. The emergency power generation system according to claim 1, wherein the power generation output control means sequentially activates the plurality of second power generation devices after the first power generation device is independently activated in the power failure start-up process. The first power generator is configured to perform power generation voltage control for adjusting a power generation output so as to maintain an output voltage at the reference voltage;
The power generation output control means sets the set power generation output of the first power generation device to a predetermined set partial power generation output smaller than the rated power generation output of the first power generation device in the power generation output control at the time of power failure. The emergency power generation system according to 2. A difference signal output means for outputting a power generation output difference signal corresponding to a difference between an actual power generation output and the set power generation output of the first power generation device;
The said power generation output control means controls the power generation output of a said 2nd power generator so that the power generation output difference signal output from the said difference signal output means may become fixed in the said power generation output control at the time of a power failure. The emergency power generation system according to any one of the above.   The emergency power generation system according to claim 4, further comprising a limiter that limits the power generation output difference signal to a set lower limit value or more.

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