JPH02220115A - Driving power unit for nuclear reactor recirculating pump motor - Google Patents

Abstract

PURPOSE:To attain the stable output control of a nuclear reactor by using a static variable voltage frequency power supply consisting of a rectifier, an inverter, etc., a synchronous rotary phase modifier connected to the voltage frequency power supply, and a controller which controls the reactive power and the voltage/frequency of the rotary phase modifier to constant. CONSTITUTION:The pump motors 8a and 8b are usually operated at the speeds of nuclear reactor recirculating pumps 7a and 7b which are equivalent to the output of a reactor. A controller 26a detects a power factor corresponding to the load state of a static variable voltage frequency power supply. Then a synchronous rotary phase modifier 21a supplies a part or the whole of the nuclear reactive power for the voltage frequency power supply. Therefore, the harmful voltage drop is never caused for a transformer 14 set in a power plant. Thus the stable control is attained for the driving speed of the pump 7a. If a power system has a hit, the controller 26a and the modifier 21a convert the inertia energy of the modifier 21a produced by the revolutions into the electric energy. This electric energy is supplied to the static variable voltage frequency power supply. As a result, the pump 7a is operated with no influence received from a hit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a power supply device for driving a recirculation pump motor of a boiling water nuclear reactor.

(Prior art) In boiling water nuclear power plants, heat is removed from the reactor core and steam is generated by forced circulation of coolant in the reactor pressure vessel housing the reactor core, and the flow rate of the coolant is reduced. By changing this, the nuclear reactivity of the reactor core is adjusted and the output of the plant is controlled.

As means for forcibly circulating the coolant, there is an external recirculation type circulation device using a reactor recirculation pump installed outside the reactor pressure vessel.

The overall configuration diagram of FIG. 2 shows a nuclear reactor, an external recirculation type circulation device, and a power supply device for driving a pump motor installed in this device. A reactor core 2 is housed inside the reactor pressure vessel 1, and a steam pipe 3 and a steam valve 4 connected to a steam outlet nozzle are installed in the surrounding wall of the reactor pressure vessel 1.
is provided. In addition, a plurality of jet pumps 5 are disposed in a circumferential manner in the middle of the reactor pressure vessel 1, surrounding the reactor core 2, and are filled with a coolant 6 including the reactor core 2. The jet pump 5 is divided into two systems, and this coolant 6 is forcedly circulated to the reactor core 2 by two reactor recirculation pumps 7a and 7b provided in each system.

The reactor recirculation pumps 7a and 7b are driven by pump motors 8a and 8b, respectively, and their power supplies include input transformers 10a and 10b and a rectifier 11, respectively.
a.

11b, inverter devices 12a, 12b, and output transformers 13a, 13b.

(Issue 8 to be solved by the invention) In the static variable voltage frequency power supply devices 9a and 9b, the power factor of the entire device is determined by the control angle of the rectifiers 11a and 11b, and this control angle is generally set to a value with a margin. If you choose , the power factor of the power supply will be low and reactive power will be required. Furthermore, if the margin is reduced and the power factor is increased, a problem arises in that the overload withstand capacity is reduced. However, when the reactive power increases,
If the capacity of the station transformer 14 and distribution lines were not increased, a drop in power supply voltage would occur, which would affect the control of the reactor recirculation pumps 7a and 7b, and thus affect stable reactor power control.

The present invention has been made in view of the above, and its purpose is to improve the operating power factor by arranging a synchronous phase modifier in parallel to a static variable voltage frequency power supply, and to increase the overload capacity of the power supply. Therefore, it is an object of the present invention to provide a power supply device for driving a nuclear reactor recirculation pump motor that can stably and efficiently control the reactor output.

[Structure of the invention] (Means for solving communication problems) A stationary variable voltage frequency power supply consisting of a rectifier, an inverter, etc., a synchronous phase modifier connected to this power supply side, and a control device for controlling its reactive power and voltage/frequency constant. Be equipped.

(Function) The power factor drop that occurs when the recirculation pump motor is driven by a variable voltage frequency power supply is compensated for by supplying corresponding reactive power by the synchronous phase modifier and its control device, and increasing the power on the variable voltage frequency power supply side. In addition to improving the overload capacity of the power supply system by improving the overload capacity of the power supply system, even in the event of a momentary power outage, the inertial energy of the synchronous phase modifier is released to prevent voltage fluctuations and stable operation of the recirculation pump. Enables stable control of furnace output.

(Example) An embodiment of the present invention will be described with reference to the drawings.

Note that the same components as those in the prior art described above are designated by the same reference numerals and detailed explanations will be omitted.

FIG. 1 is a power supply system diagram of the reactor recirculation pump motor, in which AC power reaches the high voltage bus 1B via the station transformer 14 and breaker 15. Furthermore, breaker 17g and 17
The power is supplied to the reactor recirculation pump motor drive power supplies 20a and 20b via the power supply terminal B. In addition to the high voltage bus 16, power is also supplied to various auxiliary equipment transformers 19 via a circuit breaker 18.

Power supply device 20a for driving the reactor recirculation pump motor.

Taking one of the reactor recirculation pump motor drive power supply devices 20a as an example, 20b is connected to the downstream of the breaker 17a, and is a pump motor 8a that drives the reactor recirculation pump 7a that is its load. In between, an input transformer 10a, a rectifier 11a, an inverter device 12a and an output transformer 13
A stationary variable voltage frequency power source consisting of a is connected, and a synchronous phase modulator 22a for supplying reactive power to the power source side of the input transformer 10a is further connected. Note that this synchronous phase modifier 21a is
The field winding 22a and the field breaker 23 are associated with it.
a, an exciter 24a, a field winding 25a, and a control device 28a that controls the reactive power of the high voltage bus 16.

Next, the effect of the above configuration will be explained. Usually, the reactor recirculation pump 7a is suitable for the reactor power.

The pump motors 8a and 8b are operated at a speed of 7b, and at this time, the control device 28a detects the power factor according to the load condition of the stationary variable voltage frequency power source, and the synchronous phase modifier 21a outputs the stationary variable voltage frequency power source. Supply some or all of the required reactive power. As a result, the influence of reactive power on the station power supply system is removed and a harmful voltage drop of the station transformer 14 does not occur, so stable speed control of the reactor recirculation pump 7a, that is, stable reactor power control is possible. .

In addition, this reactor recirculation pump motor drive power supply device 20
In a, when an instantaneous power outage occurs in the power supply system, the control device 28a and the synchronous phase modifier 21a detect this instantaneous power outage, switch from reactive power control to constant (voltage)/(frequency) control, and perform synchronized control. : Since the inertial energy due to the rotation possessed by the A-phase machine 21a is converted into electrical energy and supplied to the stationary variable voltage frequency power supply, the reactor recirculation pump 7a can be operated without being affected by a momentary power outage.

Furthermore, mechanically, the harmonic power generated from the stationary variable voltage frequency power supply is absorbed by the damper winding provided on the rotor surface of the synchronous phase modifier 21a, so that the harmonic power is transmitted to other systems via the high voltage bus 16. and the negative effects propagated to auxiliary equipment can be eliminated.

Although the above description has been made regarding one power supply device 20a for driving the reactor recirculation pump motor, the same operation and effect can be obtained with the completely similar configuration for the other power supply device 20b for driving the reactor recirculation pump motor. , the combined effects of the two systems can also be obtained. Furthermore, this reactor recirculation pump motor drive power supply device can also be applied to an internal pump type in which the reactor recirculation pump is integrated with the drive motor and installed in the reactor pressure vessel 1. Of course, it is a strainer that can obtain the same action and effect as the example.

[Effects of the Invention] According to the present invention, the power factor on the power source side of the stationary variable voltage frequency power source can be maintained regardless of the state of the stationary variable voltage frequency power source and the reactor recirculation pump motor driven by the stationary variable voltage frequency power source. The improvements have been made to increase overload capacity, prevent voltage drops even during momentary power outages, realize stable operation of the reactor recirculation pump motor, and enable stable output control of the reactor. There is.

[Brief explanation of the drawing]

FIG. 1 is a power supply system diagram of a nuclear reactor recirculation pump motor according to the present invention, and FIG. 2 is an overall configuration diagram of a recirculation pump system of a conventional boiling water reactor. 7a, 7b...Reactor recirculation pump, 8a, 8b
...Pump motor, 10a, fob...Input transformer, 11a, l
lb - Rectifier, 12a, 12b... Inverter device, 13a,
13b... Output transformer, 1B... High voltage bus bar, 20a, 20b... Reactor recirculation pump motor drive power supply device, 21
a, 21b...Synchronous phase adjuster, 22a, 22b
, 25a, 25b - field winding, 23a,
23b...field breaker, 24a, 24b--
- Exciter, 28a, 6b...control device. Agent: Patent Attorney Norihiro Ogo 1st Attorney

Claims (1)

[Claims] In the power supply device that drives the recirculation pump motor of a boiling water reactor, there is a stationary variable voltage frequency power supply consisting of a rectifier, an inverter, etc., a synchronous phase modifier connected to this power supply side, and its reactive power and voltage/frequency constant. A power supply device for driving a nuclear reactor recirculation pump motor, comprising a control device.