JPH11332107A - Starter for generator set - Google Patents

Abstract

(57) [Problem] To provide a starting device of a power generator that synchronizes a plurality of generators and performs parallel operation to supply power to a load in a short time. A plurality of power generation sets each including a generator, a prime mover, a rotation speed setting device, and a circuit breaker are provided, and these power generation sets are connected to a common generator bus, operated in parallel, and started to supply power to a load. In the device, a frequency deviation determiner and a phase difference determiner for checking whether the frequency difference between the generator and the generator bus is within the allowable range for synchronizing, and a frequency difference determined by the actual frequency difference between the generator and the generator bus. An automatic synchronizing device that controls the generator frequency by controlling the rotation speed setting device so that the frequency deviation and the phase difference are synchronously input while controlling the frequency of the generator and the generator bus to a predetermined frequency difference Since the generator is synchronized with the generator bus at the time when the condition is satisfied, the time to start supplying power to the load can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generator using a plurality of generators, in which a plurality of prime movers are started by a start command signal, synchronized, and operated in parallel to supply power to a load in a short time. It relates to a starting device.

[0002]

2. Description of the Related Art FIG. 11 shows a configuration of a conventional power supply system for a power generator using a plurality of generators. In the power supply system shown in the figure, 1 is a commercial power system, 2 is a power receiving circuit breaker, 3 is a general load, 4 is a communication circuit breaker, 5 is a disaster prevention load, 6
Is a generator bus connection circuit breaker. 7a is a No. 1 generator breaker, 8a is a No. 1 generator, 9a is a No. 1 motor, and 10a is a 1 motor.
No. 1 automatic voltage regulator, 11a is No. 1 governor, 12a is No. 1 speed setting device, 13a is No. 1 automatic synchronous input device, 14a
Is a No. 1 manual speed reduction contact, 15a is a No. 1 manual speed increase contact, 16a is a No. 1 automatic speed reduction contact, 17a is 1
7b is a 2nd generator breaker, 8b is a 2nd generator, 9b is a 2nd prime mover, 10b is a 2nd automatic voltage regulator, 11b is a 2nd governor, and 12b is 2nd.
No. rotation speed setting device, 13b is No. 2 automatic synchronous feeding device, 14
Reference numeral b denotes a No. 2 manual rotation speed decreasing contact, 15b denotes a No. 2 manual rotation speed increasing contact, 16b denotes a No. 2 automatic rotation speed decreasing contact, 17b denotes a No. 2 automatic rotation speed increasing contact, and 18 denotes a generator bus.

Next, the operation of the above-described conventional power supply system will be described. A conventional power supply system is configured to supply power from a commercial power system to a load during normal times, disconnect the commercial power system when the commercial power system fails, and supply power only from a generator to a disaster prevention load. That is, in normal times, the first generator 8a and the second generator 8b do not operate, and the circuit breakers 6, 7a, and 7b are open. The general load 3 and the disaster prevention load 5 are supplied with power from the commercial power system 1 with the circuit breakers 2 and 4 closed. When the commercial power system fails, the circuit breakers 2 and 4 are opened. Thereafter, the first generator 8a and the second generator 8b are started, and the generator breaker of the generator which has been started first, for example, if the first generator 8a starts faster, the first generator breaker 7a and the first generator 8
a, the generator bus 18 is charged. At this time, before the circuit breaker 7a is turned on, the generator bus 18 is out of power, so that the first automatic turning-on device 13a is not operated. Next, the frequency and phase of the terminal voltage of the second generator 8b, which was started with a delay by the second automatic synchronizing device 13b, are matched with the frequency and phase of the voltage of the generator bus 18, and the breaker 7b is turned on and parallel. drive. Thereafter, the circuit breaker 6 is turned on to supply power to the disaster prevention load 5.

The automatic voltage regulators 10a, 10b
Maintains the terminal voltages of the generators 8a and 8b at a predetermined constant voltage, and the governors 11a and 11b maintain the rotation speeds of the prime movers 9a and 9b at commanded values. Rotation speed setting device 12
a and 12b set the rotational speed command values of the prime movers 9a and 9b and transmit them to the governor. When changing the rotation speed of each of the prime movers 9a and 9b, the contacts 14a, 14b, 15a and 15b are used. In the rotation speed setting devices 12a and 12b, the contact is O
The number-of-rotations command value is changed in proportion to the N time. The operation of the automatic synchronous input devices 13a and 13b for synchronous input is performed by the contact 1 connected in parallel with these contacts and operating by logical sum.
6a, 16b, 17a, 17b, the rotational speed setting device 12
a, 12b.

FIG. 12 shows a conventional automatic synchronization input device 13a,
It is a block diagram of 13b. In the figure, 100 and 101 are frequency detectors, 102 is a subtractor that calculates a frequency deviation, and 103 is a pulse calculator that changes the set values of the rotation speed setting units 12a and 12b according to the polarity and the amount of the frequency deviation. , 104 is a frequency deviation determiner for detecting that the frequency deviation is within a predetermined range, 105 is a phase difference determiner for detecting that the phase difference is within a predetermined range, and 106 is a frequency deviation determiner 104. This is a closing commander that takes a logical product of both output signals of the phase difference determining unit 105 and sends a closing command to the circuit breakers 7a and 7b.

When the second generator 8b is inserted into the generator bus 18 by the automatic synchronizing device 13b, the second generator 8b
And the frequency of the generator bus 18 is detected,
For example, if it is high, the contact 16b is turned ON for a time corresponding to the deviation amount in order to send a command to decrease the set value to the rotation speed setting device.
Let it. The frequency deviation is within a predetermined range (for example, ±
If it falls within 0.3 Hz, the circuit breaker 7b is turned on at the moment when the phases of both voltages coincide within a predetermined range (for example, within ± 10 deg). Conversely, when the frequency of the generator is lower than the frequency of the generator bus, the operation of operating the contact 17b to increase the rotation speed set value and drive the frequency within a predetermined deviation is performed.

If the frequency deviation between the two voltages is large and the closing time of the circuit breaker is too long to be ignored, the allowable range of the phase difference is considered to be -30 to -10 deg.
May be set to a value of range. It is also possible to automatically calculate the set value from the frequency difference and the breaker closing delay time.

[0008]

As described above, the conventional power generator starting device is a system in which the frequency and phase difference of two generators are matched by an automatic synchronous input device, and the power is synchronously input. However, in this system, synchronization may take a long time. FIG. 13 is a waveform diagram showing a change with time of the voltage between both terminals of the circuit breaker 7b before the circuit breaker 7b is turned on in the above description of the operation. FIG. 13 (a) shows the No. 2 generator and the generator bus, that is, 1 FIG. 3 is a waveform diagram when the frequency difference between the power generators is relatively large, and FIG.

The point at which the envelope of the voltage waveform shown in FIG. 13 becomes zero is the timing at which the voltage phases of the first and second generators coincide, and the envelope of the voltage waveform becomes maximum. Is that the voltage phase of the first generator and the second generator is 180de
g. The breaker is turned on at the timing when the phases match within a predetermined range. The cycle of the change of the envelope in FIG. 13 is inversely proportional to the frequency difference between the first generator and the second generator. When the frequency difference is large, the cycle is short, and when the frequency difference is small, the cycle is long. As shown in FIG. 13A, when the frequency difference is relatively large, the timing at which synchronization can be performed repeatedly occurs in a short cycle, so that synchronization can be performed in a short time.

On the other hand, the automatic synchronizing device used in the conventional starting device of the power generator operates to minimize the frequency difference. FIG. 14 is a diagram showing a change with time in the relationship between the rotational phase angles of the rotors of the first and second generators before and after the synchronization. The arrow in the figure indicates the synchronization input timing. FIG. 11A shows a case where the frequency difference is large, and FIG. 10B shows a case where the frequency difference is small. The phase angle difference at the time of closing is the same in both cases.

FIG. 14 is based on the rotor phase angle of the first generator before being turned on. After the synchronization, the phase angle difference attenuates while oscillating and reaches zero. As shown in FIG. 14, if the frequency difference is large, the phase vibration after the synchronization is input is greatly increased in both the amplitude and the settling time. If the frequency difference becomes larger than that shown in FIG. 3A, it may be possible to lose synchronization due to synchronization failure. Therefore, conventionally, the frequency difference is made as small as possible and the synchronization is performed. However, when the automatic synchronization input device makes the frequency difference between the two generators very small before the automatic synchronization input, FIG.
As shown in (b), it takes a long time to match the phases, and it takes a long time until the circuit breaker is synchronously turned on.

In an emergency power generator, there is a case where it is necessary to supply power to a disaster prevention load about 40 seconds after a power failure is detected.
For example, when the frequency difference between the two generators is equal to 0.05 Hz, the timing at which the phases match will appear only once every 20 seconds. Therefore, in consideration of the starting time of the prime mover, there is a possibility that power may not be supplied within 40 seconds after the detection of the power failure.

The present invention (corresponding to claims 1 to 6 and claims 10 to 12) has been made in view of the above situation, and an object thereof is to provide a power supply system using a plurality of generators. It is an object of the present invention to provide a starting device for a power generator that synchronizes the generators and performs an operation of supplying power to a load by performing parallel operation in a short time.

Another object of the present invention (corresponding to claims 7 to 9 and claim 12) is that the load sharing of the plurality of generators after the synchronous input is the same load sharing ratio as the generator capacity ratio. It is an object of the present invention to provide a generator starting device capable of performing the following.

[0015]

In order to achieve the above object, a first aspect of the present invention provides a generator, a prime mover for driving the generator, a governor for controlling the rotation speed of the prime mover,
A rotation speed setting device for setting a rotation speed command value of the governor;
A power generator set comprising a plurality of generator sets each including a circuit breaker for turning on and off the output of the generator, and a starter of the power generator for supplying power to a load by connecting these power sets to a common generator bus and operating in parallel. A frequency deviation determiner for checking whether or not the frequency difference between the generator and the generator bus is within the allowable range for synchronization; and checking whether or not the phase difference between the generator and the generator bus is within the allowable range for synchronization. A phase difference determiner, a frequency difference setting device that sets a frequency difference between the generator and the generator bus, and the rotation so that an actual frequency difference between the generator and the generator bus becomes the set frequency difference. An automatic synchronizing device comprising a pulse calculator for sending a signal to the number setting device and controlling the generator frequency, controlling the frequency of the generator to a predetermined frequency difference from the frequency of the generator bus, The number deviation and phase difference at the time meets the synchronization turned condition, characterized by synchronizing put the generator sends a command to the circuit breaker to the generator bus.

According to a second aspect of the present invention, in the starting apparatus of the power generating apparatus according to the first aspect, the frequency difference setting device compares the frequency of the generator when the generator is started with the frequency of the generator bus. If the frequency is higher than the generator bus frequency, set the frequency difference setting value so that the generator frequency is higher than the generator bus frequency.If the generator frequency is lower than the generator bus frequency, the generator frequency is set to the generator bus. It is characterized in that it is set to a frequency difference set value smaller than the frequency.

According to a third aspect of the present invention, in the starting device of the power generator according to the first and second aspects, the set value of the frequency difference applied to the pulse calculator is set to the output value of the frequency difference setter or to zero. A switch is provided to select whether to perform synchronization, and the frequency difference setting value is set to the value of the frequency difference setting unit when synchronous synchronization is desired to be performed at a high speed, and is set to zero when the shock of synchronization is desired to be minimized. .

According to a fourth aspect of the present invention, in the starting apparatus for a power generator according to any one of the first to third aspects, a large first threshold value is set as one or both of the frequency deviation determiner and the phase difference determiner. A first and a second setting device for setting a value and a small second value respectively are provided, and both setting values are switched to be applied to a frequency deviation judgment device or a phase difference judgment device, and synchronization is desired to be performed at high speed. In this case, the value of the first setter is set as a set value, and when it is desired to minimize the shock of synchronization, the value of the second setter is set as the set value.

According to a fifth aspect of the present invention, there is provided the starting device for a power generator according to any one of the first to fourth aspects, wherein a reset value setting device for setting a reset value of the set value of the rotation speed setting device for each power generation set. A reset switch for resetting the set value of the rotation speed setter with the reset value set in the reset value setter by a command, and the reset value of each unit of the power generation set is given a difference by a predetermined value set in advance. When the power generation set is started, a command is sent to the reset switch to perform a reset operation, and each power generation set is started with a difference in the frequency at the start.

According to a sixth aspect of the present invention, in the starting apparatus of the fifth aspect, the reset value setter detects the frequency of the generator bus instead of setting a predetermined value. A value obtained by adding a predetermined frequency difference is set as a reset value.

According to a seventh aspect of the present invention, in the starting apparatus for a power generating apparatus according to the fifth or sixth aspect, a second reset value setting device and a second reset switch are provided for each power generation set. The reset value of the second reset value setting device is the same as that of each unit. After the synchronization is completed, the second reset switch is operated to change the setting value of the rotation speed setting device to the reset value of the second reset value setting device. It is characterized by resetting.

According to an eighth aspect of the present invention, in the starting apparatus of the power generating apparatus according to the seventh aspect, the set value of the second reset value setter is a capacity ratio of each set value of the reset value setter of each unit. It is characterized by the average value incorporated.

According to a ninth aspect of the present invention, in the starter of the power generator according to the seventh aspect, the set value of the second reset value setter is a minimum value of each unit set value of the reset value setter. Features.

According to a tenth aspect of the present invention, in the starting apparatus of the fourth aspect, a timer for setting a predetermined time is provided, and if the timer is within the predetermined time set in the timer, a frequency deviation judging device is provided. And a small second value is set as a determination threshold value for both or one of the phase difference determiners, and a large first value is set after a predetermined time has elapsed. .

According to an eleventh aspect of the present invention, in the starting device of the power generator according to the first to tenth aspects, an error amplifier is used instead of the rotational speed setter and the pulse calculator, and the output signal of the error amplifier is output. It is characterized in that the governor speed is directly set.

According to a twelfth aspect of the present invention, in the starter of the power generator according to the first to eleventh aspects, a part of the components is realized by software of a microcomputer.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an automatic synchronous input device of a starting device of a power generator according to a first embodiment (corresponding to claim 1) of the present invention.

The automatic synchronization input devices 99a, 99 of this embodiment
b differs from the conventional automatic synchronization input devices 13a and 13b of FIG.
This embodiment is different from the first embodiment in that an adder / subtractor 108 and a frequency difference setting unit 107 are provided. Other configurations are the same, and the same components are denoted by the same reference numerals and description thereof will be omitted.

Next, the operation of this embodiment will be described.
In the conventional automatic synchronizing device, control is performed such that the frequency of the generator bus and the frequency of the generator output match before performing the synchronizing operation. However, in this embodiment, the adder / subtractor 10
8, the output of the frequency detector 101 and the frequency difference setting device 1
07, and then the frequency detector 100
Is subtracted, that is, the frequency of the generator output is controlled by the frequency difference setter 107 and the adder / subtractor 108 so as to be higher than the frequency of the generator bus by the frequency set by the frequency difference setter. For example, if a frequency difference of 0.2 Hz is set by the frequency difference setting device and the frequency of the generator bus is 60.0 Hz, the generator output is operated at 60.2 Hz. If the frequency difference is 0.2 Hz, the phase synchronization point occurs once every 5 seconds, and the synchronization can be started earlier. Further, the frequency difference is set by control, and does not expand to a large frequency difference that may cause a risk of step-out or the like.

With this configuration, when the generator is started, even if the frequency of the generator output matches the frequency of the generator bus, the frequency difference can be immediately expanded to a predetermined value. , So that the synchronous input can be performed quickly.

FIG. 2 is a configuration diagram of an automatic synchronous input device of a starting device of a power generating device according to a second embodiment (corresponding to claim 2) of the present invention. This embodiment is different from the first embodiment in FIG.
The difference is that a frequency difference calculator 109 for calculating the set value of the frequency difference from the frequency of the generator output and the frequency of the generator bus is provided instead of the frequency difference setter 107, and the other configuration is the same. The constituent elements are denoted by the same reference numerals, and description thereof is omitted.

For example, if the frequency of the generator bus is 60.0 Hz and the frequency of the generator output is 59.6 Hz when the generator is started, the frequency of the generator output is set to 6 as described with reference to FIG.
It takes time to increase to 0.2 Hz. Same 0.2H
If a frequency difference of z is given, the frequency of the generator output can be changed in a short time by setting it to 59.8 Hz. For this purpose, the set value of the frequency difference is set to -0.2H
z may be set.

According to this embodiment, when the generator is started, the frequency of the generator output is compared with the frequency of the generator bus. If the frequency of the generator output is higher, the frequency of the generator output is more than the predetermined frequency of the generator bus. And a frequency difference calculator 109 for setting a frequency difference that increases by a predetermined value, and sets a frequency difference that decreases by a predetermined value when the frequency difference is low. As described above, according to the present embodiment, the speed of the synchronization can be increased and the starting time can be shortened.

FIG. 3 is a block diagram of a third embodiment of the present invention (corresponding to claim 3). This embodiment is different from the first embodiment in FIG.
1 in that a switch 110 is additionally provided in the middle of a connection line connecting the frequency difference setting unit 107 and the adder / subtractor 108, and the other configuration is the same. The description is omitted.

The present embodiment is a case where the power generator is not a special-purpose power generator but a general-purpose / emergency dual-purpose power generator. As described in the related art, as an emergency power generation device, when a commercial power supply is cut off, two generators are started, run in parallel, and then load is applied. Therefore, when performing synchronous input, there is no load, and the frequency difference is large to some extent.
Even if the transient phenomenon of the change of the phase angle occurs, there is no effect on the load. However, when operating as a regular power generator, when the preceding generator bears a load and the subsequent generator is turned on with a frequency difference during operation, there is a problem because the phase angle change also affects the load. . Therefore, when operating as a regular power generator, it is better that the frequency difference at the time of synchronization is as small as possible.

In this embodiment, the switch 110 for turning on / off the frequency difference setting signal is set to the frequency difference setting unit 107 and the addition / subtraction unit 1.
08, the switch 110 is turned on / off according to the case where synchronization is desired to be performed at high speed and the case where synchronization is desired to be performed without a frequency difference. Thus, even if the power generator is used for normal or emergency use, there is no need to consider the effect on the load. Therefore, according to the present embodiment, it is possible to speed up the synchronization and shorten the starting time.

FIG. 4 is a block diagram of an automatic synchronous input device of a starting device of a power generating device according to a fourth embodiment (corresponding to claim 4) of the present invention. This embodiment is different from the third embodiment in FIG.
The first frequency deviation setting device 111, the second frequency deviation setting device 112 and the first changeover switch 113, and the first phase difference setting device 114, the second phase difference setting device 115 and the second changeover switch 116 Are added, and the other configurations are the same. Therefore, the same components are denoted by the same reference numerals and description thereof will be omitted.

In this embodiment, as in the third embodiment shown in FIG. 3, the power generator is not a special-purpose power generator, but a general-purpose / emergency dual-purpose machine. If the aim is to make synchronization input as fast as possible as an emergency power generator, the frequency deviation and phase difference that allow synchronization input can be increased to the extent that step-out does not occur at the time of input. This is because there is no load at the time of synchronous input in emergency. However, if it is used as a regular power generator, it is desirable that the shock be as small as possible during synchronous input. For this purpose, it is necessary to set a small frequency deviation or phase difference that allows synchronization. If the frequency deviation and phase difference are set optimally for the emergency power generator,
There is a problem as a regular power generator.

In this embodiment, a frequency deviation setting device 111 and a phase difference setting device 114 for an emergency operation or a frequency deviation setting device 112 and a phase difference setting device 115 for a normal operation are provided. The threshold value of the frequency deviation determiner 104 and the threshold value of the phase difference determiner 105 are switched in conjunction with the switch 110 for turning on / off the signal of the device 107.

Therefore, in the present embodiment, even if the power generator is used for normal or emergency use, it is not necessary to consider the influence on the load, and the speed of the synchronization can be increased and the starting time can be shortened.

FIG. 5 is a block diagram of a starting device of a power generator according to a fifth embodiment (corresponding to claim 5) of the present invention. The configuration of this embodiment different from the conventional starter of the power generator shown in FIG.
No. 1 and 2 in place of the automatic synchronization input devices 13a and 13b
No. 2 and No. 2 automatic synchronous input devices 99a and 99b, a start control circuit 117 and a No. 1 reset value setting device 11
8a, a No. 1 reset switch 119a, a No. 2 reset value setting device 118b, and a No. 2 reset switch 119b are added, and the other configuration is the same. Omitted.

As shown in the figure, when the starter of the power generator according to the present embodiment turns on the No. 1 reset switch 119a,
The reset value setting device 118a sends the reset value to the first rotation speed setting device 12a. At this time, the first reset value setting unit 11
8a sets the reset value of the output of the first rotation speed setting device 12a, so that the output of the first rotation speed setting device 12a is changed to the set reset value. The second reset value setting unit 118b and the second reset switch 119b are also configured to perform the same operation.

This embodiment is used only for emergency use. For example, upon detecting a power failure, the start control circuit 117 turns on the reset switches 119a and 119b to reset the rotation speed set value. At this time, the reset value setting devices 118a, 1
A value with a large frequency difference within an allowable range is set in 18b. For example, the first reset value setter has 6
A frequency difference between 60.2 Hz and 0.2 Hz is given to 0.0 Hz and the second reset value setting device. Further, the frequency difference set value in the automatic synchronization input devices 99a and 99b is also 0.2 Hz.
And keep it. When the prime mover starts, each generator is operated at this frequency, so that a synchronization point is automatically generated at a high frequency of once every 5 seconds. Since the operation is continued so that the frequency difference becomes 0.2 Hz even after the start, a stable frequency difference can be maintained. As a result, the generator bus 18 can be charged by the machine whose start has been completed quickly, and the machine whose start has been completed can be synchronously turned on at a high speed with a delay.

Although the first to fourth embodiments have been described with respect to a configuration in which the frequency at the time of starting the generator is arbitrary, as described above, in this embodiment, in addition to this, the frequency at the time of starting the generator is additionally set. Since the above frequency is set, synchronous input can be performed at a higher speed than in the above embodiments. Further, in the present embodiment, the case of two generators has been described. However, even with three or more generators, the generator can be started in a short time by the same control as in the present embodiment.

FIG. 6 is a block diagram of a starter of a power generator according to a sixth embodiment (corresponding to claim 6) of the present invention. The configuration of this embodiment different from the conventional starter of the power generator shown in FIG.
No. 1 and 2 in place of the automatic synchronization input devices 13a and 13b
No. 2 and No. 2 automatic synchronous input devices 99a and 99b, the operation control device 120 and the No. 1 reset value calculator 12
No. 1a, No. 1 reset switch 119a, No. 2 reset value calculator 121b, No. 2 reset switch 119b, a current detector 122, and a power detector 123 are added, and the other configuration is the same. The constituent elements are denoted by the same reference numerals, and description thereof is omitted.

1 when the power consumption of the general load 3 is small.
Power is supplied by one of the No. 2 generator 8a and the No. 2 generator 8b. In the present embodiment, the power consumption of the load is detected by the current detector 122 and the power detector 123, and when the power consumption increases and reaches an amount that cannot be met by one generator, the operation control device 120 sets another one. The generator is started and synchronously supplied to the running generator to supply power in parallel operation. In this case, there is a problem that the second generator cannot cope with the increase in load unless it is started within a short time.

The starter of the power generator according to the present embodiment can operate in parallel in a short period of time basically with the same operation as that of the fifth embodiment in FIG. The problem is that the frequency of the generator that is supplying power is not constant. This is because the governors 11a and 11b have a droop characteristic, and the frequency fluctuates depending on the load amount. In order to cope with this, the reset value of the rotational speed set value when starting the second generator is set to the generator bus frequency at that time by the first reset value calculator 121a or the second reset value calculator 121b. Are added to obtain a value obtained by adding the frequency deviation.

With such a configuration, the second generator is started at a frequency following the fluctuating frequency of the generator bus and having a large frequency difference within an allowable range. Therefore, the operation is controlled at a frequency having a predetermined frequency difference from the generator bus frequency, so that synchronization can be performed in a short time.

As described above, the present embodiment relates to a power generator which is used in normal operation and operates independently, and has been described in the case of two generators. Short-time starting can be realized by similar control.

FIG. 7 is a block diagram of a starting device of a power generator according to a seventh embodiment (corresponding to claim 7) of the present invention. This embodiment is different from the fifth embodiment in FIG.
Is replaced by a new start control circuit 124, a second first reset value setting device 125a, a second first reset switch 126a, and a second second reset value setting device 12
5b and a second No. 2 reset switch 126b are added, and other configurations are the same. Therefore, the same components are denoted by the same reference numerals and description thereof will be omitted.

In the first to sixth embodiments, the frequency difference between the two generators has been set to be as large as possible within an allowable range in order to perform the synchronous input in a short time. There is a possibility that the load balance of both generators after parallel operation may not be even. Governor 11a,
If the speed arbitration rates of 11b are the same, the load sharing ratio of both generators will not be the same as the capacity ratio of the generators unless the rotation speed set values for both generators are the same. A heavy load will be applied to any of the generators. If the frequency difference at the time of synchronous application is not negligible (for example, about 0.3 Hz) compared to the governor droop amount (the droop amount of the rotational speed at 100% load, for example, 1 Hz), the load is applied after the synchronous application. Load imbalance increases, and the load that can be applied decreases.

In this embodiment, a second first reset value setting device 125a for setting the rotation speed set values of the two prime movers 9a and 9b after the synchronization is input, and a second second reset value setting device The same setting value is set by the circuit breaker 125b, and when a breaker closing command is input from the automatic synchronous closing device 99a or 99b of the generator to be switched on in the new start control circuit 124, the new starting control circuit 124 immediately or after a predetermined time has elapsed. 2 by the reset switches 126a and 126b.
The configuration is such that the rotational speed set values of a and 12b are reset to the values set by the second reset value setters 125a and 125b. As a result, the load sharing ratio after synchronous input can be made to match the generator capacity ratio, and imbalance in load sharing can be prevented. As described above, the present embodiment has been described in the case of two generators. However, even with three or more generators, the generator can be started in a short time by the same control.

A first modification of the seventh embodiment shown in FIG.
Correspondence) sets the setting values of the second first reset value setting device 125a and the second second reset value setting device 125b to the first reset value setting device 118a and the second reset value setting device 118b.
Is the average of the set values.

When the first and second generators are switched in at a different frequency and the two motors have the same capacity and the governor droop characteristic is linear (a characteristic in which the output and the rotational speed change are proportional). The frequency after the synchronization is the average value of the frequencies before the synchronization.

When the set value of the number of revolutions is reset after the synchronizing operation by the starter of the power generator of the seventh embodiment, the frequency is settled while vibrating transiently. In order to rapidly attenuate the transient vibration, it is advisable to reduce the amount of disturbance as much as possible, and it is preferable that the set value of the second reset value setter be set to the average value of the frequency before closing. This can minimize transient phenomena.

When the number of generators is three or more, the same effect can be obtained if the average value of the number is used. When the capacities of the generators are different, the average frequency f _M may be obtained by the following equation in consideration of the capacity ratio instead of the simple average.
f _M = (f ₁ × P ₁ + f ₂ × P ₂ ... + f _n × P _n ) ÷
_{(P 1 + P 2 ... +} P n)

FIG. 7 shows a second modification of the seventh embodiment.
Correspondence) sets the setting values of the second first reset value setting device 125a and the second second reset value setting device 125b to the first reset value setting circuit 118a and the second reset value setting device 118.
This is the same as the lower set value of the set value of b.

When the generator 1 and the generator 2 are turned on with a frequency difference, if the droop characteristic of the governor is non-linear (a characteristic in which the output and the change in the number of rotations are not proportional), the frequency after the synchronization is turned on It cannot be easily calculated. in this case,
In order to quickly attenuate the transient vibration after the synchronous input, the governor control is required to settle as quickly as possible.

Normally, a prime mover is equipped with a supercharger, and the response to increase the torque becomes slow due to the delay. The response to reduce the torque is fast because it can be realized only by reducing the fuel. As a result, the governor control response is faster in the direction of decreasing the rotation speed. Therefore, the set value of the second first reset value setter 125a and the second second reset value setter 125b is set to the lower one of the set values of the first reset value setter 118a and the second reset value setter 118b. If the configuration is the same as the set value, the transient vibration can be quickly attenuated.

Although the present embodiment has been described for the case of two generators, the setting of the second reset value setting device is set to the smallest value of the reset value setting device even when the number of generators is three or more. If a value is set, the same effect as in the present embodiment can be obtained.

FIG. 8 shows a tenth embodiment of the present invention.
It is a block diagram of the starting device of the power generation device of correspondence). The configuration of the present embodiment different from the conventional power generator starting device of FIG.
The first and second automatic synchronous injection devices 127a and 127b are used instead of the first and second automatic synchronous injection devices 13a and 13b, and the rotational speed command value is directly transmitted to the governors 11a and 11b.
Is output to In addition, the first automatic synchronization input device 127a or the second automatic synchronization input device 127b
However, the configuration different from the automatic synchronization input device 99a or 99b of the first embodiment of FIG. 1 is that an error amplifier 128 is used instead of the pulse calculator 103 as shown in FIG. Since other configurations of the present embodiment are the same as those of FIGS. 1 and 11, the same components are denoted by the same reference numerals and description thereof will be omitted.

In FIGS. 8 and 9, in this embodiment, when the governors 9a and 9b are analog voltage signals and are of a type that can directly set a rotation speed command value, the rotation speed setting device shown in the conventional example of FIG. If a voltage signal obtained by amplifying the output of the adder / subtractor 108 by the error amplifier 128 as the rotational speed command value without using the 12a and 12b is given, the frequency difference between the generator and the generator bus is determined during the synchronization control. Can be controlled to the set value. At this time, P
An ID controller or the like can be used, and stable control with faster response is possible.

FIG. 10 shows a tenth embodiment of the present invention.
1 is a configuration diagram of an automatic synchronous input device of a starting device of a power generator (corresponding to No. 1). This embodiment is different from the fourth embodiment in FIG. 4 in that a timer 129 is added, and other configurations are the same. Therefore, the same components are denoted by the same reference numerals and the description thereof will be omitted.

In this embodiment, when the synchronous control is started, the frequency deviation and the phase difference are set as the permissible input values of the frequency deviation and the phase difference by the frequency deviation setting unit 112 and the phase difference setting unit 114 until the predetermined time set by the timer 129. A small value is used and the frequency of the generator and the generator bus is controlled without deviation. Then, if the synchronous injection can be performed, the shock can be kept small. After a predetermined time set by the timer 129, the large value set by the frequency deviation setting unit 112 and the phase difference setting unit 114 is used as the allowable value of the frequency deviation and the phase difference, and the frequency of the generator and the generator bus is used. The synchronous control is performed at a high speed with a deviation, so that the probability of occurrence of a shock at the time of synchronous input is made as low as possible.

In each of the embodiments and the modified examples described above, each block in the block diagram is described as independent hardware. However, the present invention is not limited to this, and a part or all of the control device may be implemented by a microcontroller. It can be realized by computer software (corresponding to claim 12). For example, when the rotation speed setting device and the automatic synchronization input device are realized by microcomputer software, changing the rotation speed setting value is not done through contacts, but rather by passing data between individual programs. However, even with such a method, the present invention can be realized. That is, the technical idea of the present invention can be realized by either hardware or software, and is not limited to only one of them.

[0066]

As described above, the present invention (Claim 1)
To claim 6 and claims 10 to 12)
In a power supply system using a plurality of generators, the synchronization can be speeded up by operating the generator with a large and constant frequency difference within an allowable range when the generator is started, so that the start-up time can be reduced. . Thus, the emergency generator can quickly supply power to the disaster prevention load at the time of a commercial power system blackout. Further, in a normal power generation device, the generated power can be made to respond promptly in accordance with a change in load.

Further, according to the present invention (corresponding to claims 7 to 9 and claim 12), the load sharing ratio of the plurality of generators after the synchronous input is set to the same load sharing ratio as the generator capacity ratio. As a result, the maximum input load can be ensured.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an automatic synchronous input device of a starting device of a power generating device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an automatic synchronization input device of a starting device of a power generation device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of an automatic synchronous input device of a starting device of a power generation device according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram of an automatic synchronization input device of a starting device of a power generation device according to a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram of a starting device of a power generator according to a fifth embodiment of the present invention.

FIG. 6 is a configuration diagram of a starter of a power generator according to a sixth embodiment of the present invention.

FIG. 7 is a configuration diagram of a starter of a power generator according to a seventh embodiment of the present invention.

FIG. 8 is a configuration diagram of a power generator starting device according to a tenth embodiment of the present invention.

FIG. 9 is a configuration diagram of the automatic synchronization input device of FIG. 8;

FIG. 10 is a configuration diagram of an automatic synchronization input device of a starting device of a power generation device according to a modification of the tenth embodiment of the present invention.

FIG. 11 is a configuration diagram of a power supply system using a conventional power generator starting device.

FIG. 12 is a configuration diagram of the automatic synchronization input device of FIG. 11;

FIG. 13 is a characteristic diagram for explaining the operation of a starting device of a conventional power generator.

FIG. 14 is a characteristic diagram for explaining the operation of a starting device of a conventional power generator.

[Explanation of symbols]

1: commercial power system, 2: power receiving circuit breaker, 3: general load, 4
... Communication breaker, 5 ... Disaster prevention load, 6 ... Generator bus connection breaker, 7a ... No.1 generator breaker, 7b ... No.2 generator breaker, 8a ... No.1 generator, 8b ... No.2 generator , 9a ... No. 1 motor, 9b ... No. 2 motor, 10a ... No. 1 automatic voltage regulator, 10b ... No. 2 automatic voltage regulator, 11a ... No. 1 governor, 11b ... No. 2 governor, 12a ... No. 1 rotation speed setting vessel,
12b: No. 2 rotation speed setting device, 13a: No. 1 automatic synchronization input device, 13b: No. 2 automatic synchronization input device, 14a: No. 1 manual rotation speed reduction contact, 14b: No. 2 manual rotation speed reduction contact,
15a: No. 1 manual rotation speed increasing contact, 15b: No. 2 manual rotation speed increasing contact, 16a: No. 1 automatic rotation speed reducing contact, 16
b ... No. 2 automatic rotation speed reduction contact, 17a ... No. 1 automatic rotation speed increasing contact, 17b ... No. 2 automatic rotation speed increasing contact, 18 ... Generator bus, 99a ... No. 1 automatic synchronous input device, 99b ... 2
No. 100, 101 ... frequency detector,
102: subtractor, 103: pulse calculator, 104: frequency deviation determiner, 105: phase difference determiner, 106: closing commander, 107: frequency difference setter, 108: adder / subtractor, 1
09: frequency difference calculator, 110: switch, 111: first frequency deviation setter, 112: second frequency deviation setter, 113: first changeover switch, 114: first phase difference setter, 115 ... second phase difference setting device, 116 ... second
Switch 117, start control circuit 118a ... 1
No. reset value setting device, 118b ... No. 2 reset value setting device, 119a ... No. 1 reset switch, 119b ... No. 2 reset switch, 120 ... Operation control device, 121a,
121b: reset value calculator, 122: current detector, 1
23 ... power detector, 124 ... new starting control circuit, 12
5a: a second No. 1 reset value setting device, 125b: a second No. 2 reset value setting device, 126a: a second No. 1 reset switch, 126b: a second No. 2 reset switch, 1
27a: second automatic synchronization input device for No. 1 127b: second
No. 2 automatic synchronous input device, 128 ... error amplifier, 129
... timer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masafumi Mossawa 1000, Hamada, Aboshi-ku, Himeji City, Hyogo Prefecture Inside (72) Inventor Shigeto Watanabe 1000, Hamada, Abashiri-ku, Himeji City, Hyogo Prefecture Inside the company (72) Inventor Matsumoto Outside left 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. (72) Inventor Takao Ogata 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd.

Claims (12)

[Claims] 1. A generator, a prime mover for driving the generator, a governor for controlling the rotational speed of the prime mover, a rotational speed setting device for setting a rotational speed command value of the governor, and an output of the generator A plurality of generator sets each including a circuit breaker that performs ON-OFF of the generator set, and a starter of the power generator for connecting these power generation sets to a common generator bus and operating in parallel to supply power to the load; A frequency deviation determiner for checking whether or not the frequency difference between the generator buses is within a synchronization allowable range; and a phase difference determiner for checking whether or not the phase difference between the generator and the generator bus is within a synchronization allowable range. A frequency difference setting device for setting a frequency difference between the generator and the generator bus, and a signal to the rotation speed setting device such that an actual frequency difference between the generator and the generator bus becomes the set frequency difference. Send the departure An automatic synchronization input device comprising a pulse calculator for controlling the electric machine frequency, and while controlling the frequency of the generator to a predetermined frequency difference from the frequency of the generator bus, the frequency deviation and the phase difference determine the synchronization input condition. A starting device for a power generator, wherein a command is sent to the circuit breaker when the condition is satisfied to synchronize the generator with the generator bus. 2. The generator according to claim 1, wherein the frequency difference setting unit compares the generator frequency when the generator is started with the frequency of the generator bus, and determines that the generator frequency is equal to the generator bus frequency. If the generator frequency is larger than the generator bus frequency, set the frequency difference set value so that it is larger than the generator bus frequency.If the generator frequency is smaller than the generator bus frequency, the generator frequency is smaller than the generator bus frequency. A starting device for a power generator, wherein the starting device is set to a frequency difference set value. 3. A switch for switching between a set value of a frequency difference given to a pulse calculator and an output value of a frequency difference setter or zero in the starter of the power generator according to claim 1. A starting device for a power generator, wherein the setting value of the frequency difference is set to the value of the frequency difference setting device when synchronous synchronization is desired to be performed at high speed, and is set to zero when the shock of synchronizing is desired to be minimized. 4. A starting apparatus for a power generating apparatus according to claim 1, wherein a large first value and a small second value are used as judgment thresholds of at least one of the frequency deviation judging device and the phase difference judging device. First and second setting devices for setting the respective values are provided, and both the setting values are switched to be provided to the frequency deviation determiner or the phase difference determiner. A starting device for a power generator, wherein a value of a second setting device is set as a setting value when a value of a setting device is set as a setting value and it is desired to minimize a shock of synchronization. 5. A starting device for a power generator according to claim 1, wherein a reset value setter for setting a reset value of a set value of a rotation speed setter for each power generation set, and said reset value set by a command. A reset switch is provided to reset the set value of the rotation speed setter with the reset value set in the setter, and the reset value of each unit of the power generation set is set with a predetermined difference, and the power generation set is started. A starting device for a power generating device, wherein a command is sent to said reset switch to perform a reset operation, and each of the power generating sets is started with a different frequency at the time of starting. 6. The starter for a power generator according to claim 5, wherein the reset value setter detects the frequency of the generator bus and adds a predetermined frequency difference to the value instead of setting the predetermined value. A starting device for a power generator, wherein the reset value is a reset value. 7. The starting device for a power generator according to claim 5, further comprising a second reset value setting device and a second reset switch provided for each power generation set, wherein the second reset value setting device is provided. The reset value of each unit is the same, and after completion of synchronization, the second reset switch is operated to reset the set value of the rotation speed setting device to the reset value of the second reset value setting device. The starting device of the power generating device. 8. The starting device for a power generator according to claim 7, wherein the set value of the second reset value setter is an average value incorporating the capacity ratio of each unit of the set value of the reset value setter of each unit. A starting device for a power generating device, characterized in that: 9. The starter for a power generator according to claim 7, wherein the set value of the second reset value setter is a minimum value of each unit set value of the reset value setter. Starting device. 10. A starting device for a power generating apparatus according to claim 4, further comprising a timer for setting a predetermined time, and a timer for setting a predetermined time set in said timer. A starting device for a power generator, wherein a small second value is set as both or one of the determination thresholds, and a large first value is set after a predetermined time has elapsed. 11. A starting device for a power generator according to claim 1, wherein an error amplifier is used instead of the rotation speed setting device and the pulse calculator, and the output signal of the error amplifier is directly set to the rotation speed of the governor. A starting device for a power generator, wherein the starting value is set to a value. 12. A starting apparatus for a power generator according to claim 1, wherein a part of the constituent elements is realized by software of a micro computer.