JP2004242397A - Power facility for emergency motor of power generation plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable the use of an induction motor of standards of measure, by substituting an inexpensive induction motor for an expensive DC motor and adopting a DC booster (chopper booster). <P>SOLUTION: In a power system within a power station comprising a high-voltage AC bus 5, which supplies power to an in-station auxiliary machine located inside a power station in a power plant, an emergency diesel generator 11, which is connected to the high-voltage bus and supplies AC power at the loss of the external power of the plant, a low-voltage AC bus 1 connected via a step-down transformer 3 from the high-voltage AC bus; and a DC power facility 24 which is connected to the low-voltage bus and comprises a charger 13, a storage battery 15, and a DC bus 14, a DC booster 20 connected to the charger is provided, and a plurality of inverters 18 are connected via a bus 19 for power supply to an emergency motor to the DC booster; and emergency induction motors 34 are installed separately for each inverter, and each emergency induction motor is supplied with power from each inverter in emergency situations of the plant. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

よって、約１．１倍にて定格電圧２００Ｖに対応可能
＜放電終止電圧時点＞

よって、約１．３倍にて定格電圧２００Ｖに対応可能
【００１２】
図７は、本発明の他の実施形態を示す。
本実施形態は、図１に対して一組の直流昇圧装置（チョッパ昇圧装置）２０、直流交流逆変換装置（インバータ）１８によって複数の誘導電動機３４、３４’を運転、制御するものである。
これにより、図１の構成に対し、直流昇圧装置（チョッパ昇圧装置）２０、直流交流逆変換装置（インバータ）１８の台数を少なくすることができる。
しかしながら、誘導電動機３４は、起動時、定格電流の数倍（５〜７倍）の始動電流が流れることから、直流交流逆変換装置（インバータ）１８にて誘導電動機３４を起動する場合、前述した様に、低電圧／低周波数で起動し、その後、電圧／周波数一定にて昇速していく必要があるが、接続される誘導電動機３４の起動タイミンク゛が異なる場合、直流交流逆変換装置（インバータ）１８の制御が複雑になる。即ち、直流交流逆変換装置（インバータ）１８の制御によって一台の誘導電動機３４を起動する場合は、低周波数（数Ｈｚ：始動周波数）から電圧／周波数一定制御により、誘導電動機３４の始動電流を抑えることができるが、誘導電動機３４が運転している時に、他の誘導電動機３４’を始動する為に、誘導電動機３４’の誘導電動機受電遮断器３７を投入すると、誘導電動機３４’には定格電圧が印加され、定格電流の数倍の始動電流が流れ、接続線の電圧低下による他の運転している誘導電動機３４への影響、もしくは、直流交流逆変換装置（インバータ）１８が過電流状態となり、トリップする事象が発生する可能性がある。
この為、運転している誘導電動機３４の周波数を一旦始動周波数まで下げ、改めて誘導電動機３４’の誘導電動機受電遮断器３７を投入し、誘導電動機３４’を始動させる必要がある。
以上の説明の様に、いずれにしても、本実施形態の場合は、接続される負荷（誘導電動機３４、３４’）の運転条件（起動／停止等）が同一の場合が望ましい。
【００１３】
図８は、本発明の他の実施形態を示す。
本実施形態は、図１および図７に示す直流昇圧装置（チョッパ昇圧装置）２０に代えて直流交流逆変換装置１８の出力側に昇圧変圧器３１を用いた。
本実施形態は、直流昇圧装置（チョッパ昇圧装置）２０を用いることなく、誘導電動機３４が必要とする電圧まで昇圧することができる。
しかし、前述した様に、蓄電池１５は、放電直後から放電終止の間で放電電圧が変化するため、この変化分を直流交流逆変換装置（インバータ）１８で吸収する必要がある。即ち、放電終止電圧の時に、直流交流逆変換装置（インバータ）１８の定格電圧が出力できる様、放電直後の電圧時には直流交流逆変換装置（インバータ）１８の出力を絞る制御方式とする。また、前述した様に、誘導電動機３４は低周波数／低電圧で始動しなければ、大きな始動電流が流れてしまうが、低周波数領域で昇圧変圧器３１を適用すると、昇圧変圧器３１が飽和してしまい、直流交流逆変換装置（インバータ）１８を介して変圧器過大な励磁電流が流れてしまう。これを防ぐには、より飽和しにくい（鉄芯断面の大きな）昇圧変圧器３１を使用しなければならない等の問題がある。
【００１４】
【発明の効果】
以上説明したように、本発明によれば、高価で、且つメンテナンスが困難な直流電動機の使用に代えて、安価で、且つメンテナンスが容易な誘導電動機を使用することができ、さらには、標準規格の誘導電動機を使用することができる。
また、従来必要であった蓄電池の容量低減のための始動抵抗器の設置が不要となり、電源設備としての経済的効果の向上を図ることができる。
また、直流交流逆変換装置（インバータ）のＶ／ｆ一定制御の適用により、電動機始動時の電流を小さくすることが可能となり、結果として蓄電池の容量を低減することができる。
【図面の簡単な説明】
【図１】本発明による発電プラント用の非常用電動機用電源設備の一実施形態
【図２】原子炉隔離時冷却系の系統構成図
【図３】発電機の系統構成図
【図４】タービン油ポンプの運転シーケンス図
【図５】本発明の非常用電動機用電源設備（抜粋）を構成する機器の電圧波形図
【図６】従来の原子力発電所非常用電動機用電源設備
【図７】本発明の他の実施形態
【図８】本発明の他の実施形態
【符号の説明】
１…非常用低圧母線、２…非常用低圧母線受電遮断器、３…降圧変圧器、４…非常用高圧母線、５…常用高圧母線、６…所内変圧器、７…発電機負荷開閉器、８…発電機、９…主変圧器、１０…主変圧器用遮断器、１１…非常用ディーゼル発電設備、１２…直流電源設備用受電遮断器、１３…充電器、１４…直流母線、１５…蓄電池、１６…蓄電池用遮断器、１７…蓄電池出力用電流計、１８…直流交流逆変換装置（インバータ）、１９…非常用電動機給電用母線、２０…直流昇圧装置（チョッパ昇圧装置）、２１…発電機軸受、２２…主油ポンプ、２３…補助油ポンプ、２４…直流電源設備、２５…非常用油ポンプ、２６…ＲＣＩＣタービン、２７…ＲＣＩＣポンプ、２８…サプレッションチャンバ、２９…主タービン、３０…油タンク、３１…昇圧変圧器、３２…始動抵抗器、３３…原子炉、３４…誘導電動機、３５…直流電動機、３６…定電圧制御装置（ＡＶＲ）、３７…誘導電動機受電遮断器、３８…ＲＣＩＣポンプ用電動弁[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a power plant for an emergency motor for a power plant, and more particularly to a power plant that requires operation until the start of an emergency diesel generator when all AC power is lost and when external power is lost. The present invention relates to a power supply system for an electric motor.
[0002]
[Prior art]
FIG. 6 shows an outline of a power supply facility in a conventional nuclear power plant. During normal operation of the plant, the steam generated in the reactor 33 is sent to the main turbine 29 to rotate the generator 8 to generate power. The power generated by the generator 8 is boosted by the main transformer 9 via the generator load switch 7 and then transmitted to the outside via the main transformer circuit breaker 10. On the other hand, after being stepped down by the in-house transformer 6 via the generator load switch 7, the voltage is stepped down by the service high-voltage bus 5, the emergency high-voltage bus 4, and further by the step-down transformer 3, and then the emergency low-voltage bus power receiving circuit breaker 2 Power is supplied to the in-house load connected to each bus via the emergency low-voltage bus 1.
On the other hand, when the generator 8 is stopped, by opening the generator load switch 7, power is supplied from the external power supply system to each local load through the main transformer circuit breaker 10 and the main transformer 9 in the same manner as described above. I do.
In addition, in the event of an external power loss event in which both the generator 8 and the external power supply lose power supply capacity due to the occurrence of a system accident or the like, the emergency diesel power generation equipment 11 connected to the emergency high-voltage bus 4 starts, and operation is required at this time. Power is supplied to the in-house load. Further, when a superimposed event such as failure of the startup of the emergency diesel power generation equipment 11 when the external power supply is lost occurs, the power generation plant loses all the AC power supply. Power is supplied to
The DC power supply 24 includes a power receiving circuit breaker 12, a charger 13, a DC bus 14, a storage battery breaker 16, a storage battery output ammeter 17, a DC load, and the like, in addition to the storage battery 15. The DC power supply 24 is supplied with power from the emergency low-voltage bus 1 during normal operation of the plant. The charger 13 converts an AC power supply into a DC power supply, float-charges the storage battery 15, and powers the plant via the DC bus 14. Supply power to control equipment that requires DC power during normal operation. At this time, the input / output current of the storage battery 15 is constantly monitored by the storage battery output ammeter 17 on the output side of the storage battery 15.
Representative loads connected to the DC power supply 24 include a generator emergency oil pump 25 and, in a nuclear power plant, an RCIC pump motor-operated valve 38 of a reactor isolation cooling facility (RCIC).
Conventionally, the drive motor used for the emergency oil pump 25 and the like and the RCIC pump electric valve 38 of the cooling system for the nuclear power plant when the reactor is isolated uses the DC motor 35 because it is connected to a DC power supply. . The DC motor 35 includes a starting resistor 32 for the purpose of limiting the discharge current of the storage battery. The starting resistor 32 has three or four resistance taps. The starting resistor 32 is inserted in series with the circuit of the DC motor 35 and the voltage applied to the DC motor 35 is divided by the starting resistor 32 so that the DC motor 35 Limit the starting current of the motor. The maximum resistance value of the starting resistor 32 is selected such that the current flowing when the DC motor 35 is started is suppressed to about three times the rated current (maximum output current value). When the current of the DC motor 35 decreases to the rated current at the maximum resistance value of the starting resistor 32, the tap of the starting resistor 32 is lowered to gradually reduce the resistance value of the starting resistor 32. Thereafter, this operation is repeated, and when the resistance value of the starting resistor 32 becomes 0, the entire voltage is applied to the DC motor 35.
On the other hand, the rotation speed of the DC motor 35 changes according to the terminal voltage, as shown by the following equation (1).
N = k × E / Φ = k × (V-RaIa) / Φ (1)
Here, N: rotation speed, E: counter electromotive voltage, V: terminal voltage, Φ: magnetic flux of each pole Ra: armature resistance, Ia: armature current, k: proportional constant Since the voltage drops from the maximum value (equivalent to the charger output voltage) to the discharge end voltage, the rotation speed of the DC motor 35 connected to the storage battery 15 changes according to the above equation (1). On the other hand, the load of the pump and the like is a load having a square torque characteristic of the rotation speed. Therefore, when the rotation speed changes, the load torque changes, and accordingly, the required current also changes. As a result, the current of the DC motor 35 and the DC motor surveillance test at the time of the voltage drop immediately after the discharge of the storage battery such as immediately after the occurrence of an accident and the vicinity of the discharge end voltage (test for confirming the soundness of the emergency equipment standing by at the normal time of the plant) The current of the DC motor 35 at the time of the voltage during the constant floating charging is different, making it difficult to settle the electrical protection of the DC motor 35, and the DC motor 35 tends to overload during a high DC voltage surveillance test. And so on.
In addition, the DC motor 35 has a problem that the cost is large and the maintenance work is large because the structure is more complicated than the induction motor 34.
[0003]
As a known example that solves such a problem, there is, for example, Patent Document 1 “Emergency power supply device for power plant”. In this known example, a DC / AC inverter (inverter) and an induction motor are applied to applications in which a DC motor is conventionally used. However, in the known example, the control of the DC / AC inverter (inverter) is complicated in order to correct the voltage drop due to the discharge of the storage battery. Further, since the DC power supply equipment applied to the power plant is also a control power supply, it is difficult to arbitrarily set the voltage of the storage battery. On the other hand, a DC-AC inverter (inverter) cannot generate an AC having a peak value higher than the DC voltage input by the DC-AC conversion, and therefore has an induction motor having a rated voltage suitable for the voltage of the installed storage battery. Therefore, there is a problem that it is difficult to apply a standard-standard induction motor because of the necessity of applying the induction motor, and it is difficult to take advantage of the application of the induction motor.
[0004]
[Patent Document 1]
JP 2001-238368 A
[Problems to be solved by the invention]
An object of the present invention is to change an expensive DC motor to an inexpensive induction motor, and to use a DC booster (chopper booster) to enable use of a standard induction motor.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a power booster connected to a charger, a DC booster connected to a charger, and a DC booster connected to a charger in a power plant of a power plant, a DC power supply including a storage battery and a DC bus. And an inverter that converts the power into AC power, and an emergency induction motor that is fed from the inverter in the event of a plant emergency.
Here, a plurality of emergency induction motors are connected to the DC booster via an emergency motor power supply bus, and an inverter is installed for each emergency induction motor. Supplies power to each emergency induction motor.
Here, a set of inverters is connected to the DC booster, and a plurality of emergency induction motors are connected to the set of inverters via an emergency motor power supply bus. Power is supplied from the converter to a plurality of emergency induction motors.
Also, in an emergency motor power supply system including a DC power supply system including a charger, a storage battery, and a DC bus in a power plant of a power plant, an inverter for converting DC to AC connected to the charger, and an inverter. A step-up transformer connected to the converter is provided, and a plurality of emergency induction motors are connected to the step-up transformer via an emergency motor power supply bus. As a result, the voltage is raised to the voltage required by the emergency induction motor.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of a power supply system for an emergency motor for a power plant according to the present invention.
In FIG. 1, during normal operation, the generator 8 is rotated by sending steam generated in the nuclear reactor 33 to the main turbine 29 to generate power. The power generated by the generator 8 is boosted by the main transformer 9 via the generator load switch 7 and then transmitted to the outside via the main transformer circuit breaker 10. On the other hand, after being stepped down by the in-house transformer 6 via the generator load switch 7, the voltage is stepped down by the service high-voltage bus 5, the emergency high-voltage bus 4, and further by the step-down transformer 3, and then the emergency low-voltage bus power receiving circuit breaker 2 , Power is supplied to each in-house load via the emergency low-voltage bus 1.
On the other hand, when the generator 8 is stopped, by opening the generator load switch 7, power is supplied from the external power supply system to each local load via the main transformer breaker 10 and the main transformer 9 in the same manner as described above. I do.
In addition, in the event of a system accident or the like, the generator 8 and the external power supply lose the power supply capability. When the external power supply is lost, the emergency diesel power generation equipment 11 connected to the emergency high-voltage bus 4 is started and the operation is required. Supply power to the load. Further, when a superimposed event such as failure of the startup of the emergency diesel power generation equipment 11 at the time of the external power loss occurs, the entire AC power supply is lost, and power is supplied from the storage battery 15 of the DC power supply equipment 24 to the load that requires operation. .
The DC power supply 24 includes a power receiving circuit breaker 12, a charger 13, a DC bus 14, a storage battery breaker 16, a storage battery output ammeter 17, and a DC load, in addition to the storage battery 15. The DC power supply 24 is supplied with power from the emergency low-voltage bus 1 during normal operation of the plant, and the charger 13 converts an AC power supply into a DC power supply, float-charges the storage battery 15, and via the DC bus 14. Power is supplied to control equipment that requires DC power during normal operation of the plant. At this time, the input / output current of the storage battery 15 is constantly monitored by the storage battery output ammeter 17 on the output side of the storage battery 15.
On the other hand, when all AC power is lost, the storage battery 15 is connected to the battery breaker 16, the DC bus 14, the DC booster (chopper booster) 20, the emergency motor power supply bus 19, and the DC / AC inverter (inverter). ) 18 to supply power to an induction motor (IM) 34 which is an emergency load. Typical examples of the emergency load include an emergency oil pump 25 and, in a nuclear power plant, an electric valve 38 for an RCIC pump of a reactor isolation cooling system (RCIC).
In the present embodiment, a DC motor (DCM), which has been conventionally applied as a valve driving motor of a cooling system at the time of reactor isolation and a driving motor of an emergency oil pump, by employing a DC / AC inverter (inverter) 18. An induction motor (IM) 34 can be applied instead of 35. Further, the use of the DC booster (chopper booster) 20 makes it possible to use an induction motor (IM) 34 of a standard specification.
[0008]
Here, the emergency oil pump 25 which is one of the loads of the DC power supply equipment 24 will be described with reference to FIG.
The emergency oil pump 25 supplies oil to the generator bearing 21 and the bearing of the main turbine 29. FIG. 1 shows a flow of refueling from the emergency oil pump 25 to the generator 8.
Regarding oil supply to the generator bearings 21, during normal operation of the plant, the bearings 21 of the generator 8 and the bearings of the main turbine 29 are oiled from the oil tank 30 by the main oil pump 22 (turbine shaft direct drive system). When the start and stop of the engine 29 are stopped, the discharge pressure and the oil amount of the main oil pump 22 become insufficient, so that the auxiliary oil pump 23 assists the oil supply to the generator bearing 21 and the main turbine 29 bearing. In an emergency, the rotational speed of the main turbine 29 is reduced, so that the amount of oil is insufficient with the main oil pump 22 alone. At this time, the shortage of oil is supplied by the auxiliary oil pump 23 driven by the AC motor. Further, when the auxiliary oil pump 23 driven by the AC motor cannot be started due to the loss of the external power supply, an emergency oil pump 25 driven by a DC motor is provided to protect the property in order to prevent damage to the bearing 21. I'm trying to start. Here, when the emergency diesel generator 11 starts and power is supplied to the auxiliary oil pump 23, the auxiliary oil pump 23 plays a role in refueling the bearings 21 of the generator, and the emergency pump 25 stops. . The details of these operations are shown in FIG.
[0009]
In addition, the cooling equipment at the time of reactor isolation, which is one of the loads of the DC power supply equipment 24, will be described with reference to FIG.
This equipment is provided for the purpose of continuously supplying the cooling water to the reactor 33 and cooling the fuel even if the reactor 33 is isolated from the main turbine 29 during the reactor transient event. In an emergency, the DC power supply 24 supplies power to the RCIC pump motor valve 38, which is an emergency load. Thereby, it is possible to control the RCIC turbine 26 driven by the steam generated by the decay heat of the reactor 33, the RCIC pump 27 that supplies water from the suppression chamber 28, and the RCIC pump electric valve 38 that controls the injection of the coolant. This allows the coolant to be injected into the reactor 33 even when the AC power is lost.
[0010]
Next, control of the DC / AC inverter (inverter) 18 of the present invention will be described with reference to FIG. FIG. 5 shows voltage waveforms of equipment constituting the emergency motor power supply equipment (excerpt) of FIG.
In FIG. 1, an induction motor 34 connected to a DC booster (chopper booster) 20 and a DC / AC inverter (inverter) 18 flows a current (starting current) several times the rated current at startup. Therefore, when starting the induction motor 34, the DC / AC inverter (inverter) 18 inputs a low voltage / low frequency to the induction motor 34 to reduce the starting current of the induction motor 34 as much as possible. Control for increasing the speed of the induction motor 34 to the rated rotational speed in a state where the frequency is constant is applied. Thus, the capacity can be adjusted to the capacity of the induction motor 34 that drives the DC booster (chopper booster) 20 and the DC / AC inverter (inverter) 18.
[0011]
Next, control of the DC booster (chopper booster) 20 will be described with reference to FIG.
As shown in FIG. 5, the output voltage of the storage battery 15, which was equivalent to the charging voltage immediately after discharging due to the characteristics of the storage battery, decreases to the discharge end voltage with the discharging time. Further, since the present storage battery is also a power source for other DC control loads as shown in FIG. 1, the voltage cannot be arbitrarily set according to the emergency motor.
On the other hand, the DC / AC inverter (inverter) 18 cannot convert the AC voltage having a peak value equal to or higher than the input DC voltage due to the characteristics of the AC / DC conversion. Therefore, the output voltage (input voltage of the emergency motor) must be determined according to the discharge end voltage.
Therefore, in this embodiment, a DC booster (chopper booster) 20 is provided on the input side of the DC / AC inverter (inverter) 18. Further, for the purpose of compensating for a drop in the storage battery voltage, a constant voltage for detecting the voltage at the output side of the DC booster (chopper booster) 20 and controlling the output voltage of the DC booster (chopper booster) 20. A control device (AVR) 36 is installed. The constant voltage controller (AVR) 36 detects the difference between the output voltage of the DC booster (chopper booster) 20 and the set value (the input voltage of the DC / AC inverting converter 18) at all times. The boosting rate of the boosting device 20 is controlled. Therefore, even when the storage battery voltage decreases, the input voltage of the DC / AC inverter (inverter) 18 can be kept constant at all times.
The boosting rate of the DC booster (chopper booster) 20 is set based on the rated voltage of the emergency motor connected to the discharge end voltage of the storage battery 15. That is, assuming that a charge voltage of the storage battery 15 is 260 V, a discharge end voltage is 220 V, and a rated voltage of the emergency motor is 200 V, a boosting rate of the DC boosting device (chopper boosting device) 20 becomes It becomes 1.1 times (immediately after discharge) to 1.3 times (discharge end voltage).
<Immediately after discharge>

Therefore, it is possible to support the rated voltage of 200 V at about 1.1 times <discharge end voltage>

Therefore, it is possible to support a rated voltage of 200 V at about 1.3 times.
FIG. 7 shows another embodiment of the present invention.
In the present embodiment, a plurality of induction motors 34 and 34 'are operated and controlled by a pair of a DC booster (chopper booster) 20 and a DC / AC inverter (inverter) 18 with respect to FIG.
Thus, the number of DC boosters (chopper boosters) 20 and DC / AC inverters (inverters) 18 can be reduced as compared with the configuration of FIG.
However, when the induction motor 34 is started, a starting current several times (5 to 7 times) the rated current flows at the time of starting. As described above, it is necessary to start at a low voltage / low frequency and then increase the speed at a constant voltage / frequency. However, if the starting timing of the connected induction motor 34 is different, the DC / AC inverter (inverter) ) The control of 18 becomes complicated. That is, when starting one induction motor 34 under the control of the DC / AC inverter (inverter) 18, the starting current of the induction motor 34 is controlled by the voltage / frequency constant control from a low frequency (several Hz: starting frequency). Although it can be suppressed, when the induction motor 34 'is turned on and the induction motor power receiving circuit breaker 37 of the induction motor 34' is turned on to start another induction motor 34 ', the rated value of the induction motor 34' A voltage is applied, a starting current several times the rated current flows, and an influence on the other induction motor 34 due to a voltage drop in the connection line, or a DC / AC inverter (inverter) 18 is in an overcurrent state. And a tripping event may occur.
For this reason, it is necessary to once lower the frequency of the operating induction motor 34 to the starting frequency, turn on the induction motor power receiving circuit breaker 37 of the induction motor 34 ', and start the induction motor 34'.
As described above, in any case, in the case of the present embodiment, it is desirable that the connected load (the induction motors 34, 34 ') have the same operating conditions (start / stop, etc.).
[0013]
FIG. 8 shows another embodiment of the present invention.
In this embodiment, a step-up transformer 31 is used on the output side of the DC / AC inverting device 18 instead of the DC step-up device (chopper step-up device) 20 shown in FIGS.
In the present embodiment, the voltage can be boosted to the voltage required by the induction motor 34 without using the DC booster (chopper booster) 20.
However, as described above, since the discharge voltage of the storage battery 15 changes between immediately after the discharge and the end of the discharge, the change must be absorbed by the DC / AC inverter (inverter) 18. In other words, the control method is such that the output of the DC / AC inverter (inverter) 18 is reduced at the voltage immediately after the discharge so that the rated voltage of the DC / AC inverter (inverter) 18 can be output at the discharge end voltage. As described above, if the induction motor 34 does not start at a low frequency / low voltage, a large starting current will flow. However, when the step-up transformer 31 is applied in a low frequency region, the step-up transformer 31 is saturated. As a result, an excessive excitation current flows through the transformer via the DC / AC inverter (inverter) 18. In order to prevent this, there is a problem that the step-up transformer 31 which is less likely to be saturated (having a large iron core cross section) must be used.
[0014]
【The invention's effect】
As described above, according to the present invention, an inexpensive and easy-to-maintain induction motor can be used instead of an expensive and difficult-to-maintain DC motor. Can be used.
Further, it is not necessary to install a starting resistor for reducing the capacity of the storage battery, which is conventionally required, and the economical effect as the power supply equipment can be improved.
Further, by applying the V / f constant control of the DC / AC inverter (inverter), the current at the time of starting the motor can be reduced, and as a result, the capacity of the storage battery can be reduced.
[Brief description of the drawings]
FIG. 1 is an embodiment of a power supply system for an emergency motor for a power plant according to the present invention. FIG. 2 is a system configuration diagram of a cooling system at the time of reactor isolation. FIG. 3 is a system configuration diagram of a generator. FIG. Operation sequence diagram of oil pump [Fig. 5] Voltage waveform diagram of equipment constituting power supply equipment for emergency motor of the present invention (excerpt) [Fig. 6] Power supply equipment for emergency motor of conventional nuclear power plant [Fig. 7] FIG. 8 shows another embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 ... Emergency low-voltage bus, 2 ... Emergency low-voltage bus power receiving circuit breaker, 3 ... Step-down transformer, 4 ... Emergency high-voltage bus, 5 ... Regular high-voltage bus, 6 ... Internal transformer, 7 ... Generator load switch, 8 ... Generator, 9 ... Main transformer, 10 ... Breaker for main transformer, 11 ... Emergency diesel power generation equipment, 12 ... Receiving breaker for DC power supply equipment, 13 ... Charger, 14 ... DC bus, 15 ... Storage battery , 16: battery circuit breaker, 17: storage battery output ammeter, 18: DC / AC inverter (inverter), 19: emergency motor power supply bus, 20: DC booster (chopper booster), 21: power generation Machine bearings, 22: Main oil pump, 23: Auxiliary oil pump, 24: DC power supply equipment, 25: Emergency oil pump, 26: RCIC turbine, 27: RCIC pump, 28: Suppression chamber, 29: Main turbine, 30 ... Oil tank, DESCRIPTION OF SYMBOLS 1 ... Step-up transformer, 32 ... Starting resistor, 33 ... Reactor, 34 ... Induction motor, 35 ... DC motor, 36 ... Constant voltage control device (AVR), 37 ... Induction motor receiving circuit breaker, 38 ... For RCIC pump Electric valve

Claims (7)

A high-voltage AC bus that supplies power to auxiliary equipment in a power plant in a power plant, an emergency diesel generator that is connected to the high-voltage bus and supplies AC power when the power supply outside the plant is lost, and a step-down transformer from the high-voltage AC bus. DC power booster connected to the charger in a power plant in-plant power supply system connected to the low-voltage AC bus connected through the low-voltage bus, and connected to the low-voltage bus, and configured by a DC power supply facility including a charger, a storage battery, and a DC bus And an inverter for converting a direct current to an alternating current, and an emergency induction motor fed from the inverter when the plant is in an emergency. 2. The plant according to claim 1, wherein a plurality of the emergency induction motors are connected to the DC booster via an emergency motor power supply bus, and the inverter is installed for each of the emergency induction motors. Power supply equipment for an emergency motor for a power plant, wherein power is sometimes supplied from the respective inverters to the respective emergency induction motors. 2. The plant according to claim 1, wherein a set of the inverters is connected to the DC booster, and the plurality of emergency induction motors are connected to the set of inverters via an emergency motor power supply bus. A power supply system for an emergency motor for a power plant, wherein power is supplied to the plurality of emergency induction motors from the set of inverters in an emergency. The method according to any one of claims 1 to 3, wherein a constant voltage / frequency control is applied as a control method of the inverter, and a starting current of the emergency induction motor supplied from the inverter is reduced. Power supply equipment for emergency motors for power plants. The voltage according to any one of claims 1 to 3, wherein a voltage required by the emergency induction motor fed from the inverter is output by a combination of the DC booster and the inverter. Power supply equipment for an emergency motor for a power plant, wherein a standard induction motor is used as the induction motor. The method according to any one of claims 1 to 3, wherein a constant voltage controller is connected to the DC booster to correct a voltage fluctuation due to discharging of the storage battery, and to supply a constant voltage to an input voltage to the inverter. Power supply equipment for an emergency motor for a power plant. A high-voltage AC bus that supplies power to auxiliary equipment in a power plant in a power plant, an emergency diesel generator that is connected to the high-voltage bus and supplies AC power when the power supply outside the plant is lost, and a step-down transformer from the high-voltage AC bus. And a low-voltage AC bus connected through the power supply system connected to the low-voltage bus, and configured from a DC power supply system including a charger, a storage battery, and a DC bus. An inverter and a step-up transformer connected to the inverter are provided, and a plurality of emergency induction motors are connected to the step-up transformer via an emergency motor power supply bus. After converting to AC by the inverter, boosting to a voltage required by the emergency induction motor by the step-up transformer, for a power plant. Power supply equipment for emergency motor.

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