JP2008193834A - Apparatus and method for controlling voltage of static type uninterruptible power supply - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to supply power of stable constant voltage, even though a load-carrying capacity fluctuates, when constant-voltage, constant-frequency power is supplied from a static uninterruptible power supply to a load by way of a power distribution installation disposed away from the power supply. <P>SOLUTION: The static uninterruptible power supply 30A is so constructed that a rectifier circuit 6A and an inverter circuit 7A are connected to an alternating-current power supply 1A, and constant-voltage, constant-frequency power is supplied to a load by way of the power distribution installation 16A; and when alternating-current power supply is removed, direct-current power 8A is guided to the inverter circuit, to continue power supply to the load. The uninterruptible power supply includes a voltage detector 32A, that detects the terminal voltage on the side of a distribution board disposed away from the power supply; a correction signal generating circuit that generates a correction signal 41A, by using terminal voltage signals 36A, 37 from the voltage detector and terminal reference voltage; and a voltage control circuit 35A that adjusts the output voltage 42A of the inverter circuit, by using a constant-voltage reference voltage 43A and the correction signal and carries out control so that the terminal voltage on the distribution board 16A side becomes the desired fixed voltage. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a voltage control device for a static uninterruptible power supply that feeds a constant voltage and constant frequency power supply to a load such as a computer used in an operation state centralized monitoring system of a nuclear power plant, for example.

  In the nuclear power plant, as the unit capacity of the plant increases, a centralized operation state monitoring system using many computers is introduced, and the operation state of the plant is monitored using a process computer, a color CRT, a large display panel, etc. To improve the efficiency of the interface between the operator and the plant.

  This operation state centralized monitoring system is basically composed of two redundant systems (system A monitoring system, system B monitoring system), and each monitoring system power supply facility is also considered in redundancy. In order to obtain the constant voltage and constant frequency power required by the computers constituting the monitoring system, two stationary uninterruptible power supply devices that supply a constant voltage and constant frequency power supply are installed.

  Further, the load related to the man-machine interface such as the color CRT and the large display panel can be supplied with power from either of these two stationary uninterruptible power supply devices. The switchboard to the load related to the man-machine interface has a power supply switching function.

  As described in Patent Document 1, the static uninterruptible power supply device converts AC input power to DC once by a rectifier circuit, and then converts it to AC again by an inverse converter circuit (inverter) to obtain a predetermined constant voltage. A device that outputs AC power at a constant frequency, and in particular, a circuit that can supply DC power from a separately installed DC power supply (storage battery) to the output side of the rectifier circuit in order to satisfy uninterruptible power requirements. Is provided. That is, when AC input power is lost, DC power from a separately installed DC power supply facility is supplied to the input side of the inverse conversion circuit on the output side of the rectifier circuit, so that a predetermined constant voltage constant frequency is obtained. AC power is output uninterrupted.

  This static uninterruptible power supply device constantly monitors and controls the output voltage and output frequency in an internal constant voltage control circuit in order to supply AC power of a predetermined constant voltage and constant frequency to a load.

  By the way, as shown in FIG. 5, the power supply equipment of the conventional operation state centralized monitoring system of a nuclear power plant includes an in-house AC power supply 1A and a stationary uninterruptible power supply 20A, and an in-house AC power supply. 1B and B system power supply equipment 21B provided with stationary uninterruptible power supply 20B.

  Among these, regarding the A-system power supply facility 21A, the in-house AC power supply 1A is connected to the transformer 3A of the standby power supply circuit provided in the static uninterruptible power supply 20A via the circuit breaker 2A, and the switching circuit 4A and The power supply circuit breaker 11A is connected to a step-down transformer 13A and a switchboard 16A for a process computer of the A-system monitoring system. The switching circuit 4A is connected to the circuit breaker 14A, the step-down transformer 15 and the switchboard 18 of the power supply switchboard 17 via the power supply breaker 12A. The switchboard 18 is, for example, a switchboard for a color CRT, a large display panel, or the like.

  Similarly, the in-house AC power supply 1A is connected to the switching circuit 4A via a power receiving breaker 5A, a rectifier circuit 6A, and an inverse conversion circuit 7A that form a static uninterruptible power supply 20A. Furthermore, the DC power supply 8A of the DC power supply equipment installed separately is connected to the reverse conversion circuit 7A on the output side of the rectifier circuit 6A via the DC power receiving breaker 9A and the thyristor switch 10A of the static uninterruptible power supply 20A. Connected to the input side.

  In the A-system power supply facility 21A including the stationary uninterruptible power supply 20A configured as described above, when the on-site AC power source 1A is healthy and normal, the AC power of the on-site AC power source 1A is converted to DC by the rectifier circuit 6A. This is converted into electric power, and this direct current power is reversely converted into alternating current power of a predetermined constant voltage and constant frequency by the reverse conversion circuit 7A and supplied to the switchboard 16A or 18 through the switching circuit 4A.

  When the in-house AC power supply 1A is lost, the DC power from the rectifier circuit 6A is not supplied to the reverse conversion circuit 7A. At this time, the circuit is normally opened by a control circuit (not shown) of the stationary uninterruptible power supply 20A. The thyristor switch 10A is instantaneously closed, DC power from the DC power supply 8A is input to the inverse conversion circuit 7A, and AC power of constant voltage and constant frequency is supplied to the switchboard 16A or 18 without interruption.

  The switching circuit 4A is normally connected so as to supply the constant voltage and constant frequency alternating current output from the reverse conversion circuit 7A to the switchboard 16A or 18, but at the time of maintenance on the reverse conversion circuit 7A side, or When this reverse conversion circuit 7A fails for any reason, the in-house AC power supply 1A is instantaneously switched to the transformer 3A side of the standby power supply circuit by a control circuit (not shown) of the static uninterruptible power supply 20A. The AC power of the in-house AC power source 1A is directly supplied to the switchboard 16A or 18.

  In addition, about B system power supply equipment 21B which consists of the other in-house AC power supply 1B made redundant and static type uninterruptible power supply 20B etc., since it is the structure and effect | action similar to A system power supply equipment 21A mentioned above, code | symbol The subscript is changed from A to B and the description is omitted. The thyristor switches 10A and 10B in the static uninterruptible power supply devices 20A and 20B are formed with a unidirectional circuit that supplies the DC power of the DC power supplies 8A and 8B to the reverse conversion circuits 7A and 7B when closed. In the normal case where the on-site AC power supplies 1A and 1B are healthy, the thyristor switches 10A and 10B are opened.

  By the way, as for the operation state centralized monitoring system for nuclear power plants, there is a remarkable increase in process computer load in recent years, and a static uninterruptible power supply device that has been planned with a configuration of two units having a capacity of 50 kVA in the past, As the computer load increases, the capacity per unit reaches 100 to 200 kVA.

Further, in the nuclear power plant, the stationary uninterruptible power supply devices 20A and 20B and the switchboard 16A, 16B or 18 that is a power distribution facility for the computer equipment load of the operation state centralized monitoring system are separated by about 200 m or more. Placed in place. Therefore, when the static uninterruptible power supply 20A, 20B supplies power to the switchboard 16A, 16B or 18 with a required capacity of 30-60 kVA at a voltage of 100 V required by the computer equipment load, a large size is selected for the power supply cable. There is a need. Therefore, step-down transformers 13A, 13B, and 15 are provided in the vicinity of the switchboard 16A, 16B, or 18 between the static uninterruptible power supply apparatus 20A, 20B and the switchboard 16A, 16B, or 18, and the static uninterruptible power supply apparatus 20A. , 20B and the step-down transformers 13A, 13B, and 15 are selected to have a power supply voltage of, for example, 200V or 400V to reduce the power supply current, thereby reducing the size of the power supply cable.
JP 59-129543 A

  In general, the constant voltage control of the two static uninterruptible power supply devices 20A and 20B is performed by monitoring the output voltages of the inverse conversion circuits 7A and 7B using a constant voltage control circuit (not shown). Is controlled to be a reference voltage of a constant voltage set as.

  However, the step-down transformers 13A, 13B are located in the vicinity of the switchboard 16A, 16B, or 18 between the static uninterruptible power supply devices 20A, 20B and the switchboard 16A, 16B, or 18, which are arranged at a distance of about 200 m or more. , 15 is selected, and the power supply voltage is selected to be 200 V or 400 V, for example, and the size of the power supply cable is reduced.

  That is, when the load capacity fluctuates in the distribution board 16A, 16B or 18 which is the distribution facility to the computer facility load, even if the immediate output voltage of the static uninterruptible power supply 20A, 20B is controlled to a constant voltage, The voltage on the switchboard 16A, 16B or 18 side arranged at a location separated by about 200 m or more from the static uninterruptible power supply 20A, 20B is distributed from the static uninterruptible power supply 20A, 20B to the switchboard 16A, 16B or 18 greatly varies due to a voltage drop due to the impedance of the power supply cable and the step-down transformers 13A, 13B, 15 and the like existing in the route up to 18.

  Therefore, in the constant voltage control method of the conventional static uninterruptible power supply devices 20A and 20B as described above, the power supply voltage to the computer equipment load is kept within a certain voltage fluctuation range, and stable constant voltage power is supplied to the computer equipment load. There were cases where it was difficult to supply to.

  The object of the present invention has been made in consideration of the above-mentioned circumstances, and a constant voltage constant frequency power source is supplied from a stationary uninterruptible power supply device to a load through a distribution facility arranged away from the power supply device. An object of the present invention is to provide a voltage control device and a voltage control method for a static uninterruptible power supply that can supply stable constant voltage power to a load even when the load capacity changes when power is supplied.

  In order to solve the above-described problems, a voltage control device for a static uninterruptible power supply device according to the present invention includes a rectifier circuit and an inverse conversion circuit sequentially connected to an AC power supply, and a constant voltage constant frequency power supply to a load. A static uninterruptible power supply device that continues the power supply to the load of the constant voltage constant frequency power supply by guiding the DC power supply to the inverse conversion circuit when the AC power supply is lost. A voltage detector for detecting a terminal voltage on the side, a correction signal generating circuit for generating a correction signal using the terminal voltage and the terminal reference voltage detected by the voltage detector, and an output voltage of the inverse conversion circuit A voltage control circuit that adjusts using the reference voltage of the constant voltage and the correction signal, and controls the terminal voltage on the power distribution equipment side to be a desired constant voltage. is there.

  Moreover, in order to solve the above-described problem, the voltage control device for a static uninterruptible power supply according to the present invention is configured such that a rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power supply, and a constant voltage constant frequency power supply is supplied to a load. A static uninterruptible power supply device that feeds power through a distribution facility and directs a DC power supply to the inverse conversion circuit when the AC power supply is lost, and continues to supply power to a load of a constant voltage constant frequency power supply, The load power factor calculation circuit that calculates the load power factor using the input DC power and the output AC power of the inverse conversion circuit, and the load power factor calculated by the load power factor calculation circuit and the output AC current of the inverse conversion circuit A correction signal generation circuit that calculates a voltage drop in a path from the power supply device to the power distribution facility arranged separately from the power supply device and generates a correction signal; and an output of the inverse conversion circuit Voltage, constant voltage Adjust with a reference voltage and the correction signal, terminal voltage of the distribution equipment side is characterized in that it has a voltage control circuit which controls so as to obtain a desired constant voltage.

  Furthermore, in order to solve the above-described problems, the voltage control method for a static uninterruptible power supply according to the present invention is such that a rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power supply, and a constant voltage constant frequency power supply is supplied to a load. A static uninterruptible power supply device that feeds power through a distribution facility and directs the DC power source to the inverse conversion circuit when the AC power source is lost, and continues to supply power to a load of a constant voltage constant frequency power source, The terminal voltage on the distribution equipment side is detected, a correction signal is created using the detected terminal voltage and terminal reference voltage, and the output voltage of the inverse conversion circuit is used as the constant voltage reference voltage and the correction signal. And adjusting the terminal voltage on the power distribution equipment side to be a desired constant voltage.

  In addition, in order to solve the above-described problems, the voltage control method for the static uninterruptible power supply according to the present invention is such that a rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power supply, and a constant voltage constant frequency power supply is supplied to a load. A static uninterruptible power supply device that feeds power through a distribution facility and directs a DC power supply to the inverse conversion circuit when the AC power supply is lost, and continues to supply power to a load of a constant voltage constant frequency power supply, The load power factor is calculated using the input DC power and the output AC power of the inverse conversion circuit, and the calculated load power factor and the output AC current of the inverse conversion circuit are used to transmit power from the power supply device to the distribution facility. A correction signal is created by calculating a voltage drop in the path of (1), the output voltage of the inverse conversion circuit is adjusted using a constant voltage reference voltage and the correction signal, and the terminal voltage on the power distribution equipment side is set to a desired value. Control to maintain a constant voltage A method comprising Rukoto.

  According to the present invention, the correction signal generation circuit generates a correction signal using the terminal voltage on the distribution equipment side detected by the voltage detector and the terminal reference voltage, and the voltage control circuit outputs the output voltage of the inverse conversion circuit. The terminal voltage on the distribution equipment side is controlled to be a desired constant voltage by adjusting based on the constant voltage reference voltage and the correction signal. Thus, the power supply voltage from the distribution facility to the load can be kept within a certain voltage fluctuation range, and stable constant voltage power can be supplied to the load.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the present invention is not limited to these embodiments.

[A] First embodiment (FIGS. 1 to 3)
FIG. 1 is a configuration block diagram showing a power supply facility in which a static uninterruptible power supply having the first embodiment in a voltage control apparatus for a static uninterruptible power supply according to the present invention is arranged. In the present embodiment, the same parts as those of the conventional stationary uninterruptible power supply shown in FIG.

  Also in the static uninterruptible power supply devices 30A and 30B of the present embodiment, the rectifiers 6A and 6B, the inverse conversion circuits 7A and 7B, and the switching devices 4A and 4B are sequentially connected to the on-site AC power supplies 1A and 1B, so that the constant voltage constant The frequency power supply is supplied to a load (not shown) such as a computer equipment load in an operation state centralized monitoring system of a nuclear power plant via the distribution boards 16A, 16B, and 18 as power distribution equipment, and the above-mentioned AC power supplies 1A and 1B are lost. Then, the DC power supplies 8A and 8B are led to the inverse conversion circuits 7A and 7B, and the power supply to the load of the constant voltage and constant frequency power supply is continued. Further, when the inverse conversion circuits 7A and 7B are maintained or failed, the in-house AC power supplies 1A and 1B are directly supplied to the load via the switchboards 16A, 16B and 18 by the action of the switches 4A and 4B.

  The stationary uninterruptible power supply 30B, the switchboards 16B and 18, the in-house power supply 21A including the static uninterruptible power supply 30A, the switchboards 16A and 18 and the in-house AC power supply 1A and the DC power supply 8A. Also in the B system power supply equipment 21B having the AC power supply 1B and the DC power supply 8B, the stationary uninterruptible power supply devices 30A, 30B and the switchboards 16A, 16B, 18 are arranged apart from each other by about 200 m. Step-down transformers 13A, 13B, and 15 are installed in the vicinity of the switchboards 16A, 16B, and 18 in order to suppress the size of the power feeding cable.

  Now, the static uninterruptible power supply devices 30A and 30B of the present embodiment do not control the latest output voltage constant, but to control the terminal voltage on the switchboards 16A, 16B, and 18 side to a desired constant voltage. Voltage control devices 31A and 31B. The voltage control device 31A includes voltage detectors 32A and 33, a correction signal generation circuit 34A (FIG. 3), and a voltage control circuit 35A. The voltage control device 31B includes voltage detectors 32B and 33, a correction signal generation circuit 34B ( 3) and a voltage control circuit 35B. The voltage detector 33 is a common detector in the voltage control devices 31A and 31B.

  The voltage detectors 32A, 32B, 33 detect the terminal voltages on the switchboards 16A, 16B, 18 side, that is, the secondary voltages of the step-down transformers 13A, 13B, 15 installed in the vicinity of the switchboards 16A, 16B, 18 respectively. Thus, the terminal voltage signals 36A, 36B, and 37 are output, respectively. The terminal voltage signal 36A indicates a power supply voltage supplied from the static uninterruptible power supply 30A to the switchboard 16A. The terminal voltage signal 36B indicates a power supply voltage supplied from the static uninterruptible power supply 30B to the switchboard 16B. The terminal voltage signal 37 indicates a power supply voltage supplied to the switchboard 18 from the stationary uninterruptible power supply 30A or 30B.

  The correction signal generation circuit 34A shown in FIG. 3 uses the terminal voltage signals 36A and 37 and the terminal reference voltage, for example, to generate a correction signal 41A from their deviations. Similarly, the correction signal generating circuit 34B uses the terminal voltage signals 36B and 37 and the terminal reference voltage to generate a correction signal 41B from the deviation thereof, for example. Specifically, the correction signal generation circuits 34A and 34B include an intermediate value / low value selection circuit 38, a limiter 39, and a normalization circuit 40.

  The intermediate value / low value selection circuit 38 of the correction signal generating circuit 34A calculates and selects the intermediate value of the input terminal voltage signals 36A and 37, or gives priority to the lower value of the terminal voltage signals 36A and 37. To select. Further, the intermediate value / low value selection circuit 38 of the correction signal generation circuit 34B calculates and selects the intermediate value of the input terminal voltage signals 36B and 37, or selects the lower value of the terminal voltage signals 36B and 37. Select with priority.

  Here, as shown in FIG. 1, the switchboard 18 is configured to be supplied with power from either the static uninterruptible power supply 30 </ b> A or 30 </ b> B via the power supply switchboard 17. For this reason, the terminal voltage signal 37 is input to the intermediate value / low value selection circuit 38 of the correction signal generating circuit 34A only when the circuit breaker 14A of the power switching board 17 is closed, and the terminal voltage signal is output when the circuit breaker 14A is opened. 37 input is blocked. Similarly, the terminal voltage signal 37 is input to the intermediate value / low value selection circuit 38 of the correction signal generation circuit 34B only when the circuit breaker 14B of the power supply switchboard 17 is closed, and when the circuit breaker 14B is opened, the terminal voltage signal is input. 37 input is blocked.

  The limiter 39 of the correction signal generation circuits 34A and 34B limits the signal value from the intermediate value / low value selection circuit 38 within an allowable fluctuation range with respect to the terminal reference voltage (for example, ± 10V with respect to the terminal reference voltage). Thus, it is possible to prevent the correction signals 41A and 41B that are created from becoming excessively large.

  The normalization circuit 40 of the correction signal generation circuits 34A and 34B converts the signal value from the limiter 39 into a ratio based on the terminal reference voltage, and from the deviation between the value calculated using this ratio converted value and the terminal reference voltage, Correction signals 41A and 41B are generated and output with the undervoltage relative to the terminal reference voltage as a correction voltage. The correction signal generated by the normalization circuit 40 of the correction signal generation circuit 34A is referred to as a correction signal 41A, and the correction signal generated by the normalization circuit 40 of the correction signal generation circuit 34B is referred to as a correction signal 41B.

  As shown in FIG. 2, the voltage control circuit 35A adjusts the output voltage 42A of the inverse conversion circuit 7A using the constant voltage reference voltage 43A and the correction signal 41A, and the terminal voltage on the switchboards 16A, 18 side (terminal voltage). (Corresponding to the signals 36A and 38) is controlled so as to be a desired constant voltage. Similarly, the voltage control circuit 35B (FIG. 1) adjusts the output voltage 42B of the inverse conversion circuit 7B using the constant voltage reference voltage 43B and the correction signal 41B, and the terminal voltage (terminal voltage) on the switchboards 16B and 18 side. (Corresponding to the signals 36B and 38) is controlled to have a desired constant voltage.

  The voltage control circuit 35A will be described in detail as an example. As shown in FIG. 2, the voltage control circuit 35A monitors the output voltage 42A of the inverse conversion circuit 7A, and adds a constant voltage reference voltage 43A to the addition circuit and the correction signal generated by the correction signal generation circuit 34A. 41A is input to create a voltage control signal 44A, and this voltage control signal 44A is input to a control unit (not shown) of the inverse conversion circuit 7A. When the output voltage 42A of the inverse conversion circuit 7A is lower than the added value of the constant voltage reference voltage 43A and the correction signal 41A, the voltage control signal 44A is sent to the control unit of the inverse conversion circuit 7A as a voltage increase signal. Is output. As a result, the control unit of the inverse conversion circuit 7A adjusts the output voltage 42A of the inverse conversion circuit 7A to a value higher than the constant voltage reference voltage 43A, and the terminal voltage on the switchboards 16A, 18 side (terminal voltage signal 36A). , 38)) to a desired constant voltage.

  Similarly, as shown in FIG. 1, the voltage control circuit 35B adds the constant voltage reference voltage 43B and the correction signal 41B to the output voltage 42B of the inverse conversion circuit 7B to create a voltage control signal 44B. The terminal voltage (corresponding to the terminal voltage signals 36B and 38) on the switchboards 16B and 18 side controls the output voltage 42B of the inverse conversion circuit 7B so that it is a desired constant voltage.

  With the configuration as described above, according to the above embodiment, the following effects are obtained.

  According to the voltage control devices 31A and 31B of the stationary uninterruptible power supply device, the correction signal using the terminal voltage on the switchboards 16A, 16B and 18 side detected by the voltage detectors 32A, 32B and 33 and the terminal reference voltage The creation circuits 34A and 34B create the correction signals 41A and 41B, and the voltage control circuits 35A and 35B use the output voltages 42A and 42B of the inverse conversion circuits 7A and 7B as the constant voltage reference voltages 43A and 43B and the correction signal 41A, The terminal voltage (corresponding to the terminal voltage signals 36A, 36B, 38) on the switchboards 16A, 16B, 18 side is controlled to be a desired constant voltage by adjusting based on 41B. From this, even when the load capacity fluctuates, the load (in the operation state centralized monitoring system of the nuclear power plant) is distributed from the switchboards 16A, 16B, 18 arranged away from the stationary uninterruptible power supply devices 20A, 20B. The power supply voltage to the computer equipment load or the like can be kept within a certain voltage fluctuation range, and stable constant voltage power can be supplied to the load.

[B] Second embodiment (FIG. 4)
FIG. 4 is a block diagram showing the configuration of a second embodiment of the voltage control device for a static uninterruptible power supply according to the present invention. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The static uninterruptible power supply devices 30A and 30B in the present embodiment do not control the output voltage of the power supply device immediately, but control the terminal voltage on the switchboards 16A, 16B and 18 to a desired constant voltage. Voltage control devices 51A and 51B are provided. However, in the present embodiment, the voltage control device 51B of the static uninterruptible power supply 30B has the same configuration and operation as the voltage control device 51A of the static uninterruptible power supply 30A. Only the control device 51A will be described.

  The voltage control device 51A of the static uninterruptible power supply 30A includes a load power factor calculation circuit 52A, a correction signal creation circuit 53A, and a voltage control circuit 54A.

The load power factor calculation circuit 52A receives the input DC power (input DC voltage (Vd) 55A and input DC current (Id) 56A) to the inverse conversion circuit 7A in the static uninterruptible power supply 30A and the inverse conversion circuit 7A. Using the output AC power (output AC voltage (Va) 57A and output AC current (Ia) 58A), the load power factor (cos θ) is calculated by the following equation (1), and the calculated load power factor signal 59A is corrected. Output to the creation circuit 53A.

The correction signal generating circuit 53A includes a step-down transformer 13A in the vicinity of the switchboards 16A and 18 that are arranged at a distance of about 200 m or more from the stationary uninterruptible power supply 30A immediately after the stationary uninterruptible power supply 30A. , 15 impedance (Z) to the secondary side is input in advance. The correction signal generation circuit 53A uses the load power factor calculated by the load power factor calculation circuit 52A, the output alternating current (Ia) 58A of the inverse conversion circuit 7A, and the impedance (Z) of the path to stop the correction power generation circuit 53A. The voltage drop (ΔV) in the above path from immediately after the uninterruptible power supply 30A to immediately before the switchboards 16A and 18 is calculated using the following equation (2).

  Next, the correction signal creation circuit 53A cancels the calculated voltage drop (ΔV) and corrects the terminal voltage on the switchboards 16A, 18 side (corresponding to the terminal voltage signals 36A, 38) to the terminal reference voltage. Signal 60A is created.

  The voltage control circuit 54A adjusts the output voltage (output AC voltage (Va) 57A) of the inverse conversion circuit 7A using the voltage reference voltage 43A and the correction signal 60A, and the terminal voltage on the switchboards 16A, 18 side is desired. Control to a constant voltage. That is, the voltage control circuit 54A monitors the output voltage (output AC voltage (Va) 57A) of the inverse conversion circuit 7A, and is created by the constant voltage reference voltage 43A and the correction signal creation circuit 53A in the addition circuit. The correction signal 60A is input to create a voltage control signal 61A, and this voltage control signal 61A is input to a control unit (not shown) of the inverse conversion circuit 7A. When the output voltage (output AC voltage (Va) 57A) of the inverse conversion circuit 7A is lower than the sum of the constant voltage reference voltage 43A and the correction signal 60A, the voltage control signal 61A is used as a voltage increase signal. It is output to the control unit of the inverse conversion circuit 7A. Thereby, the control part of the reverse conversion circuit 7A adjusts the output voltage (output AC voltage (Va) 57A) of the reverse conversion circuit 7A to a value higher than the reference voltage 43A of the constant voltage, and the switchboards 16A, 18 side The terminal voltage (corresponding to the terminal voltage signals 36A and 38) is controlled to a desired constant voltage.

  Therefore, according to the present embodiment, the following effects can be obtained.

  According to the voltage control device 51A of the static uninterruptible power supply 30A, the input DC power (input DC voltage (Vd) 55A and input DC current (Id) 56A) of the reverse conversion circuit 7A and output AC power (output AC voltage) The load power factor calculation circuit 52A calculates the load power factor using (Va) 57A and the output AC current (Ia) 58A), and uses the calculated load power factor and the output AC current 58A of the inverse conversion circuit 7A. The correction signal generation circuit 53A calculates a voltage drop (ΔV) in the path from the static uninterruptible power supply 30A to the switchboards 16A and 18 to generate the correction signal 60A. Then, the voltage control circuit 54A adjusts the output voltage (output AC voltage (Va) 57A) of the inverse conversion circuit 7A by using the constant voltage reference voltage 43A and the correction signal 60A, so that the power distribution board 16A, 18 side The terminal voltage (corresponding to the terminal voltage signals 36A and 38) is controlled to be a desired constant voltage. From this, even when the load capacity fluctuates, the load (for example, the computer equipment in the operation state centralized monitoring system of the nuclear power plant) from the switchboards 16A and 18 arranged separately from the stationary uninterruptible power supply 30A. The power supply voltage to the load or the like can be kept within a certain voltage fluctuation range, and stable and constant power can be supplied to the load. The same effect can be obtained in the voltage control device 51B of the stationary uninterruptible power supply 30B.

The block diagram which shows the power supply installation by which the stationary uninterruptible power supply provided with 1st Embodiment in the voltage control apparatus of the static uninterruptible power supply which concerns on this invention is arrange | positioned. The block diagram which mainly shows the voltage control circuit in the voltage control apparatus of the static uninterruptible power supply apparatus of FIG. The block diagram which shows the correction signal preparation circuit in the voltage control apparatus of the static uninterruptible power supply apparatus of FIG. The block diagram which shows 2nd Embodiment in the voltage control apparatus of the stationary uninterruptible power supply which concerns on this invention. The block diagram which shows the power supply installation with which the conventional static type uninterruptible power supply device was installed.

Explanation of symbols

1A, 1B In-house AC power supply 6A, 6B Rectifier circuit 7A, 7B Inverse conversion circuit 8A, 8B DC power supply 16A, 16B, 18 Distribution board (distribution equipment)
30A, 30B Static uninterruptible power supply 31A, 31B Voltage controller 32A, 32B, 33 Voltage detector 34A, 34B Correction signal generation circuit 35A, 35B Voltage control circuit 36A, 36B, 37 Terminal voltage signal 41A, 41B Correction signal 42A 42B Output voltage 43A, 43B Constant voltage reference voltage 44A, 44B Voltage control signal 51A, 51B Voltage controller 52A Load power factor calculation circuit 53A Correction signal creation circuit 54A Voltage control circuit 55A Input DC voltage (Vd)
56A Input DC current (Id)
57A Output AC voltage (Va)
58A Output AC current (Ia)
59A Calculated load power factor signal 60A Correction signal 61A Voltage control signal

Claims (4)

A rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power source, and a constant voltage constant frequency power source is supplied to a load through a distribution facility. When the AC power source is lost, the DC power source is led to the inverse conversion circuit to A static uninterruptible power supply that continues to supply power to the load of the voltage constant frequency power supply,
A voltage detector for detecting a terminal voltage on the power distribution facility side;
A correction signal generating circuit that generates a correction signal using the terminal voltage and the terminal reference voltage detected by the voltage detector;
A voltage control circuit that adjusts an output voltage of the inverse conversion circuit using a reference voltage of a constant voltage and the correction signal, and controls the terminal voltage on the distribution facility side to be a desired constant voltage; A voltage control device for a static uninterruptible power supply, comprising: A rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power source, and a constant voltage constant frequency power source is supplied to a load through a distribution facility. When the AC power source is lost, the DC power source is led to the inverse conversion circuit to A static uninterruptible power supply that continues to supply power to the load of the voltage constant frequency power supply,
A load power factor calculation circuit that calculates a load power factor using input DC power and output AC power of the inverse conversion circuit;
By using the load power factor calculated by the load power factor calculation circuit and the output alternating current of the inverse conversion circuit, in the path from the power supply device to the power distribution equipment arranged away from the power supply device A correction signal generation circuit for calculating a voltage drop and generating a correction signal;
A voltage control circuit that adjusts an output voltage of the inverse conversion circuit using a reference voltage of a constant voltage and the correction signal, and controls the terminal voltage on the distribution facility side to be a desired constant voltage. A voltage control device for a static uninterruptible power supply. A rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power source, and a constant voltage constant frequency power source is supplied to a load through a distribution facility. When the AC power source is lost, the DC power source is led to the inverse conversion circuit to A static uninterruptible power supply that continues to supply power to the load of the voltage constant frequency power supply,
Detect the terminal voltage on the power distribution equipment side,
A correction signal is created using the detected terminal voltage and terminal reference voltage,
The output voltage of the inverse conversion circuit is adjusted by using a constant voltage reference voltage and the correction signal so as to control the terminal voltage on the power distribution equipment side to be a desired constant voltage. A voltage control method for an uninterruptible power supply. A rectifier circuit and an inverse conversion circuit are sequentially connected to an AC power source, and a constant voltage constant frequency power source is supplied to a load through a distribution facility. When the AC power source is lost, the DC power source is led to the inverse conversion circuit to A static uninterruptible power supply that continues to supply power to the load of the voltage constant frequency power supply,
Calculate the load power factor using the input DC power and output AC power of the inverse conversion circuit,
Using this calculated load power factor and the output alternating current of the inverse conversion circuit, calculate a voltage drop in the path from the power supply device to the power distribution facility, and create a correction signal,
The output voltage of the inverse conversion circuit is adjusted using a constant voltage reference voltage and the correction signal so as to control the terminal voltage on the power distribution equipment side to be a desired constant voltage. Voltage control method for uninterruptible power supply.

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