JP2007166727A - Generating equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide generating equipment capable of causing multiple synchronous generators to start power supply to a load in a short time. <P>SOLUTION: The generating equipment includes: the synchronous generators; automatic voltage regulators that control the voltage of each generator to a desired voltage according to a voltage command signal; a prime mover starter that is connected in parallel with multiple pieces of generating equipment through generator circuit breakers and starts each prime mover when a prime mover start signal becomes true; a timer that starts counting when a prime mover start signal becomes true and outputs a true generation start signal when a preset time lapses; and a voltage command output device that outputs a voltage command signal to each automatic voltage regulator when a generation start signal becomes true. When the generator circuit breakers and a load circuit breaker are open and an external prime mover start signal is true, a prime mover is started. When a generation start signal thereafter becomes true, all the generator circuit breakers are closed to start the voltages of the generators. After start of the voltage is completed, the load circuit breaker is externally closed to start power supply to the load. Therefore, all the generators can be synchronously turned on in a short time regardless of the number of synchronous generators. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power generator that supplies power to a load by a plurality of synchronous generators or brushless synchronous generators.

A power generation apparatus is used in which a plurality of synchronous generators are connected in parallel to supply power to the same load. A conventional example of such a power generator will be described with reference to FIG.
In the power generation device of FIG. 4, three synchronous generators are used. That is, the synchronous generators 100, 101, 102 are driven by the prime movers 103, 104, 105, respectively, and the rotational speeds of the prime movers 103, 104, 105 are controlled by the governors 106, 107, 108, respectively. The automatic voltage regulators 109, 110, 111 detect the voltages of the synchronous generators 100, 101, 102 through the transformers 112, 113, 114, respectively, and the currents of the synchronous generators 100, 101, 102, respectively. 115, 116, 117, and the amount of excitation of the generator is adjusted so that the output voltage of each synchronous generator is controlled to a desired voltage while performing cross current compensation.

  In addition, the synchronization input device 118 detects the voltage of the bus line via the transformer 120, detects the voltage of the synchronous generator 101 via the transformer 122, and receives the synchronization input start signal a, the automatic voltage A voltage command adjustment signal is output to the regulator 110 to make the voltage of the synchronous generator 101 coincide with the bus voltage. Further, a rotation speed command adjustment signal is output to the governor 107 to make the frequency and phase of the voltage of the synchronous generator 101 coincide with those of the bus voltage, and then the circuit breaker 125 is closed to connect the synchronous generator 101 to the bus. By a similar operation, the synchronous device 119 also connects the synchronous generator 102 to the bus.

  In order to start supplying power to the load 128 in the power generator of FIG. 4, for example, the motors 103, 104, and 105 are started with the circuit breakers 124, 125, 126, and 127 opened to have a rated rotational speed, and automatic The voltage control of the voltage regulators 109, 110, 111 is started to activate the voltage of the synchronous generator. After that, after closing the circuit breaker 124, a synchronous input start signal a is sent to the synchronous input device 122, and the synchronous generator 100 and the synchronous generator 101 are operated in parallel. Subsequently, a synchronous input start signal b is sent to the synchronous input device 119, and the synchronous generators 100, 101 and 102 are operated in parallel. Thereafter, the circuit breaker 127 is closed to supply power to the load 128.

  The power generator installed as an emergency power supply for disaster prevention is responsible for supplying power to the disaster prevention load within 40 seconds, which is the legal time stipulated by the Fire Service Act, in the event of a power failure. It is necessary to complete a certain number of units in parallel, and it is necessary to operate a predetermined number of units in parallel. However, synchronous activation of synchronous generators requires an operation to match the voltage, frequency, and phase of the synchronous generators, and several tens of times are required for one synchronous activation. If the number of synchronous generators is large, power supply to the disaster prevention load within 40 seconds becomes difficult. Therefore, normally, the number of synchronous generators is one, or the power generation apparatus is configured with a small number of synchronous generators, such as about two that can be synchronized in a relatively short time.

  However, when the number of synchronous generators is small, the synchronous generator capacity is determined by the capacity of the load, and thus the generator capacity cannot be freely selected. For example, there is a problem that it is not possible to employ a cost-effective synchronous generator mass-produced with a standard capacity.

  On the other hand, Patent Documents 1 and 2 disclose, for example, methods for performing synchronous charging of a plurality of synchronous generators in a short time. Patent Document 1 shows an automatic synchronous charging system for a plurality of generators that sends a synchronous charging start signal all at once to the synchronous charging devices of the respective synchronous generators, and sequentially loads the synchronous power generators with the synchronous charging conditions in order. . Further, in Patent Document 2, there is provided a synchronous generator device for a synchronous generator that can perform synchronous input in a short time by relaxing the synchronous input conditions, that is, the allowable values of voltage magnitude, frequency, and phase difference. It is shown.

  However, especially in urban areas, a gas engine is often used as the power for the power generation device in order to reduce air pollution caused by exhaust gas. However, the gas engine generally tends to be inferior in speed stability, and no load is applied. Since the frequency of the generator voltage tends to be unstable in the operating state, it may take time to synchronize. As described in Patent Document 1, the synchronous generator is started synchronously all at once, Even if the generators are turned on in order from the generators that have the same conditions for synchronous injection, it is difficult to complete the synchronous injection within the legal time and supply power to the disaster prevention load.

In addition, when the synchronous input condition is relaxed as described in Patent Document 2, the larger the number of units that are operated in parallel, the greater the possibility of damage to the synchronous generator, and the frequency and voltage difference. Since synchronous power is applied in a large state, active power and reactive power flow between the synchronous generators, and reverse power of the synchronous generator is generated, which may make it impossible to continue the parallel operation of the synchronous generators.
JP-A-6-121462 JP 2002-271996 A

  In order to solve the above-described problems, an object of the present invention is to provide a power generator that can start feeding power to a load in a short time even in a power generator including a plurality of synchronous generators.

  In order to achieve the above object, a power generator according to claim 1 of the present invention includes a synchronous generator or a brushless synchronous generator (hereinafter abbreviated as a generator) driven by a prime mover and an input rotation. A rotational speed command is determined based on a speed command adjustment signal, a governor for controlling the prime mover to a desired rotational speed, a voltage and a current of the generator are detected, and a voltage command signal inputted while performing cross current compensation is detected. An automatic voltage regulator for adjusting the field quantity of the generator so that the voltage of the generator becomes a desired voltage based on the generator, and a power generator comprising a generator breaker for connecting the output of the generator to the outside; The measurement is started at the same time as the load connected via the load circuit breaker after all of the plurality of power generation devices are connected in parallel and the input prime mover start signal becomes true. of A timer that outputs a power start signal, and a voltage command output device that outputs a voltage command signal to the automatic voltage regulator of each power generator at the same time that the power generation start signal becomes true, the generator breaker and the load breaker Is open, the prime mover start signal from the outside becomes true to start the prime mover, and then the generator start signal becomes true to close all the generator breakers and reduce the generator voltage. The power supply to the load is started by closing the load circuit breaker from the outside at an arbitrary time after the start-up and voltage start-up is completed.

  According to a second aspect of the present invention, in the power generator according to the first aspect, the time set in advance in the timer is a time from the start of the prime mover until all the prime movers reach the rated rotational speed. It is characterized by.

  According to a third aspect of the present invention, in the power generator according to the first aspect, a rotational speed detector that detects a rotational speed of the prime mover and outputs a rotational speed detection signal is installed in each prime mover, and the prime mover start signal Rotation speed that outputs the true signal when the rotation speed detection signal from all the rotation speed detectors is input and the prime mover start signal becomes true and then the rotation speed of all prime movers reaches the rated rotation speed A determination device is provided instead of the timer, and an output signal of the rotation speed determination device is used as the power generation start signal.

  According to a fourth aspect of the present invention, in the power generation apparatus according to any one of the first to third aspects, the voltage command output device automatically adjusts the voltage of each power generation apparatus at the same time that the power generation start signal becomes true. A voltage command signal that gradually increases from zero to a rated voltage command value is output to the device.

  According to a fifth aspect of the present invention, in the power generation device according to any one of the first to fourth aspects, the power detector that detects the power of the generator and outputs a power detection signal; A rotational speed command adjuster that outputs a rotational speed command adjustment signal to the governor so that input / output power of the generator is within a preset upper limit value and lower limit value based on a power detection signal; and the rotational speed A switch that opens and closes transmission of a rotational speed command adjustment signal from the command adjuster to the governor, and closes the switch when the load circuit breaker is open, and closes the load circuit breaker when the load circuit breaker is closed The switch is opened.

  According to the present invention, since all the generators can be synchronously turned on in a short time regardless of the number of synchronous generators, a generator with a free capacity can be selected without being limited by the load capacity, and the configuration of the power generator The degree of freedom can be increased.

The best mode for carrying out the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a circuit configuration diagram of a power generator according to a first embodiment of the present invention, and shows a power generator using three generators.

  As shown in FIG. 1, in this embodiment, synchronous generators or brushless synchronous generators (hereinafter abbreviated as generators) 1, 2, and 3 are driven by prime movers 4, 5, and 6, respectively. The rotational speed of 6 is controlled by governors 7, 8, and 9, respectively. The automatic voltage regulators 10, 11, and 12 detect the voltages of the generators 1, 2, and 3 through the transformers 13, 14, and 15, respectively, and the currents of the generators 1, 2, and 3, respectively. The amount of excitation of the generator is adjusted so that the output voltage of each generator is controlled to be constant to the voltage indicated by the input voltage command signal e while performing cross current compensation. The prime mover starter 19 starts the prime movers 4, 5, and 6 when the prime mover start signal s input from the outside becomes true. The timer 20 starts measuring time as soon as the input prime mover start signal s becomes true, and outputs a true power generation start signal d after a preset time has elapsed. The voltage command output unit 21 outputs a voltage command signal e to the automatic voltage regulators 10, 11, 12 when the input power generation start signal d becomes true. The circuit breakers 22, 23 and 24 are closed at the same time as the power generation start signal d becomes true.

  Since the present embodiment is configured as described above, the prime movers 4, 5, 6 are started by the prime mover start signal, and then the circuit breakers 22, 23, 24 are closed by the power generation start signal and at the same time by the voltage command output unit 21. The output voltages of the generators 1, 2, 3 can be activated via the automatic voltage regulators 10, 11, 12 respectively. As a result, the generators start up the voltage while being synchronized with each other's synchronization force, so that all the generators are synchronized after the start-up of each generator to the rated voltage. Multiple generators can be synchronized in time. When the power transmission start command g is received from the outside after the voltage activation is completed, the circuit breaker 25 is closed immediately and power supply to the load 26 is started.

  In this embodiment, the time set in advance in the timer 20 is set as the time from the start of the prime mover until all the prime movers reach the rated rotational speed. It can be eliminated and each generator can be synchronized at an early stage.

  Further, in the present embodiment, the voltage command output device 21 gradually increases the voltage command signal e from zero to the rated voltage at the same time when the power generation start signal becomes true, thereby reducing the voltage difference between the generators at the time of voltage startup. Thus, a plurality of generators can be synchronized in a short time while suppressing the current flowing between the generators.

(Second Embodiment)
FIG. 2 is a circuit configuration diagram of a power generator according to the second embodiment of the present invention. The power generator according to the present embodiment is different from the power generator according to the first embodiment shown in FIG. The rotational speed detectors 27, 28, and 29 are provided with a rotational speed determiner 30 in place of the timer 20, and the other components are the same. A duplicate description is omitted.

As shown in FIG. 2, in this embodiment, the rotational speed detectors 27, 28, and 29 detect the rotational speeds of the prime movers 4, 5, and 6, respectively, and respectively output rotational speed detection signals f ₁ , f ₂ , and f ₃ . Output. The rotational speed determiner 30 inputs the prime mover start signal s and the rotational speed detection signals f ₁ , f ₂ , f _3, and after the prime mover start signal s becomes true, the rotational speed detection signals f ₁ , f ₂ , rotational speed f ₃ is all predetermined (e.g., rated speed of the prime mover 4,5,6) Once you reach the to the circuit breaker 22, 23, 24 and the voltage command output unit outputs a true power generation start signal d. As a result, even if the time from start to start completion of all prime movers is not known, voltage start is performed after all prime movers have reached the same rotational speed. The difference in rotational speed can be eliminated, and each generator can be synchronized at an early stage.

(Third embodiment)
FIG. 3 is a circuit configuration diagram of the power generation apparatus according to the third embodiment of the present invention. The configuration of the power generation apparatus according to the present embodiment that is different from the power generation apparatus according to the first embodiment of FIG. Other features include power detectors 31, 32, 33, current transformers 34, 35, 36, rotational speed command adjusters 37, 38, 39, and switches 40, 41, 42. Since the devices are the same, the same components are denoted by the same reference numerals and redundant description is omitted.

  As shown in FIG. 3, in the present embodiment, each of the power detectors 31, 32, and 33 includes a current transformer 34, 35, 36 and a transformer 13, 14, 15. 3 is input to detect the power of the generator and output power detection signals P1, P2 and P3. Each rotation speed command adjuster 37, 38, 39 receives power detection signals P1, P2, P3, respectively, and generates power so that the active power input / output of each generator is within a preset upper limit value and lower limit value. A rotation speed command increase / decrease signal is output to the governors 7, 8, 9 when the machine power is large, and when the machine power is small, it is incremented. Each switch 40, 41, 42 is opened as soon as the circuit breaker 25 is closed.

  Since this embodiment is configured as described above, each of the governors 7, 8, 9 is limited in active power input / output to / from each generator during operation and the circuit breaker 25 is open. The generators synchronize with each other by the synchronization force while avoiding the extreme reverse power state caused by the unbalance of the rotation speed of the generators, and all generators are operated in parallel without performing the synchronous operation after the voltage startup is completed Can do. In addition, since the breaker 25 is closed by the power transmission start signal g from the outside and the respective switches 40, 41, 42 are opened at the same time, while the load 26 is being fed, the rotation speed command regulators 37, 38, 39 are respectively connected. Since the governors 7, 8, and 9 are disconnected and the restriction on the input / output power of the generator is released, the power is normally supplied to the load 26.

The circuit block diagram of the 1st Embodiment of this invention. The circuit block diagram of the 2nd Embodiment of this invention. The circuit block diagram of the 3rd Embodiment of this invention. The circuit block diagram of the conventional electric power generating apparatus.

Explanation of symbols

1, 2, 3 ... synchronous generator or brushless synchronous generator, 4, 5, 6 ... prime mover, 7, 8, 9 ... governor, 10, 11, 12 ... automatic voltage regulator, 13, 14, 15 ... transformer , 16, 17, 18 ... current transformer, 19 ... prime mover starter, 20 ... timer, 21 ... voltage command output device, 22, 23, 24, 25 ... circuit breaker, 26 ... load, 27, 28, 29 ... rotation Speed detector, 30 ... rotational speed determiner, 31, 32, 33 ... power detector, 34, 35, 36 ... current transformer, 37, 38, 39 ... rotational speed command adjuster, 40, 41, 42 ... open / close , 100, 101, 102 ... synchronous generator or brushless synchronous generator, 103, 104, 105 ... prime mover, 106, 107, 108 ... governor, 109, 110, 111 ... automatic voltage regulator, 112, 113, 114 ... Transformer, 115, 116, 17 ... current transformer, 118, 119 ... synchronous feeding device, 120, 121, 122, 123 ... transformer, 124, 125, 126, 127 ... breaker, 128 ... load.

Claims (5)

  A rotational speed command is determined based on a synchronous generator or a brushless synchronous generator (hereinafter abbreviated as a generator) driven by a prime mover and an input rotational speed command adjustment signal, and the prime mover is controlled to a desired rotational speed. And the field quantity of the generator so that the voltage of the generator becomes a desired voltage based on the voltage command signal inputted while detecting the voltage and current of the generator and performing cross current compensation. An automatic voltage regulator for adjusting, a power generator comprising a generator breaker for connecting the output of the generator to the outside, and a load connected via a load breaker after all of the plurality of power generators are connected in parallel When the input prime mover start signal becomes true, measurement starts at the same time, a timer that outputs a true power generation start signal after a preset time has elapsed, and each power generation at the same time as the power generation start signal becomes true A voltage command output device that outputs a voltage command signal to the automatic voltage regulator of the device, and when the generator circuit breaker and the load circuit breaker are open, the motor start signal from the outside becomes true, After starting the prime mover, all generator breakers are closed when the power generation start signal becomes true, and the generator voltage is started, and the load is externally applied at any time after the voltage startup is completed. A power generator that starts power supply to a load by closing a circuit breaker.   2. The power generator according to claim 1, wherein the time set in advance in the timer is a time from when the prime mover starts to when all the prime movers reach a rated rotational speed.   2. The power generator according to claim 1, wherein a rotational speed detector that detects a rotational speed of the prime mover and outputs a rotational speed detection signal is installed in each prime mover, and the rotational speed detection from the prime mover start signal and all rotational speed detectors. After the prime mover start signal becomes true after the input of the signal, a rotational speed judgment device that outputs a true signal when the rotational speed of all the prime movers reaches the rated rotational speed is provided instead of the timer, and the rotational speed A power generation apparatus characterized in that an output signal of the determination device is the power generation start signal.   The power generator according to any one of claims 1 to 3, wherein the voltage command output unit gradually increases from zero to a rated voltage command value to the automatic voltage regulator of each power generation unit at the same time when the power generation start signal becomes true. A power generation device that outputs a voltage command signal. 5. The power generation device according to claim 1, wherein the power detector detects the power of the generator and outputs a power detection signal, and the input / output of the generator based on the power detection signal. A rotation speed command adjuster that outputs a rotation speed command adjustment signal to the governor so that the power is within a preset upper limit value and lower limit value, and a rotation speed command adjustment from the rotation speed command adjuster to the governor A power switch that opens and closes signal transmission, and closes the switch when the load circuit breaker is open, and opens the switch when the load circuit breaker is closed. .

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