JPH09229977A - Phase detector for uninterruptible power supply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to realize an uninterruptible power supply with excellent stability and reliability by confirming a reference phase between a master power supply and a slave power supply by one common-phase detector, and connecting the reference phases of mutual three-phase AC generators to be in phase. SOLUTION: After it is confirmed that a master power supply 1 is connected in phase sequence and in phase with the three phases of a three-phase oscillator 7A as references by power source side in-phase detectors 8R, 8S, 8T and load side in-phase defectors 9AR, 9AT, the power supply 1 is mainly connected to a feeder 21, and power is supplied by a generator 16A. When a slave power supply 2 is operated in parallel, the supply 2 is temporarily connected at a distribution line power supply circuit 4B to a distribution line 21 while a breaker 15B remains opened, the power supplies 1, 2 are wired by a link line 27, and the in-phase connection of the reference phases of both the supplies 1, 2 is confirmed by a phase detector 13 between the power supplies 1 and 2. Then, the in-phase connection with the three phases of the oscillator 7B as reference is confirmed by the in-phase detectors 9BR, 9BT, and the generator 16B is stared, and synchronously connected by a breaker 15B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a commercial power source such as a three-phase or single-phase high-voltage distribution line, and a standby power source generated by two or more three-phase AC generators connected in parallel without interruption. The present invention relates to a phase detector for an uninterruptible power supply device, which is provided in the uninterruptible power supply device that is used simultaneously and can check the phase sequence and in-phase connection.

[0002]

2. Description of the Related Art When constructing a part of a commercial high-voltage distribution line, for example, for a load group requiring uninterruptible power supply, an AC synchronous generator of an uninterruptible power supply system is temporarily synchronized with the distribution line. It is necessary to turn it on, and in this case, it is required to connect without causing a power failure even for an instant. By the way, the conditions for synchronously inserting the AC synchronous generator in the high-voltage distribution line are that the frequency, the magnitude of each phase voltage, and each phase voltage phase are equal between the distribution line side and the uninterruptible power supply. That is.

As an uninterruptible power supply system that can meet such conditions, a phase detection device that can accurately check whether each phase voltage phase is connected in a correct state is equipped. It is an indispensable requirement, and a typical prior art relating to this type of distribution line phase detector is proposed, for example, in Japanese Patent Laid-Open No. 4-20874. This prior art is provided with a high-voltage detection unit for detecting each phase voltage of the ground reference on the power supply side and the load side in a bypass circuit of a three-phase or single-phase high-voltage distribution line, and a phase detection switch for both of these high-voltage detection units. The in-phase detector and the lag phase detector are connected via this, and the phase sequence confirmation and the in-phase confirmation can be performed by the operation and non-operation of these detectors.

[0004]

The structure of the above prior art will be described more specifically with reference to FIG. Three-phase three
When the wire-type high-voltage distribution line 21 is used as a power supply target, the circuit breaker 1
A three-phase distribution line bypass circuit 3 having 4 and a three-phase AC synchronous generator 16 and a circuit breaker 15 connected to the load side of the distribution line bypass circuit 3 In order to hot-connect a mobile power supply vehicle as a power supply device including 4 to the high-voltage distribution line 21, first, by bypass-connecting the distribution line bypass circuit 3 with both circuit breakers 14 and 15 open. Use the phase detector installed in the mobile power supply vehicle to check if the phases on the power supply side and the load side of the high-voltage distribution line 21 are correctly matched and connected. If it is correct, for the distribution line The circuit breaker 14 of the bypass circuit 3 is closed, and after the bypass circuit is formed, the section switch 24 is opened to bypass the entire amount of electricity on the load side. Then, the three-phase AC synchronous generator 16 is started, its breaker 15 is synchronously turned on, the load is transferred to the generator 16, the breaker 14 is opened, and only the output of the generator 16 is applied to the load side. Power.

Thus, the uninterruptible power supply is completed,
The phase detector has one in-phase detector 25X and three delays.
Phase detectors 25Y, 25C, 25L and two high voltage detectors
Department PT_-C, PT_-LFormed by and checking each phase
Is performed as follows. FIG. 6 is a functional explanation of the phase detector of FIG.
It is a figure, and in this figure, each phase voltage (V_R1, V_S1, V _T1
And V_R2, V_S2, V_T2) Is the high-voltage detector PT_-C, PT_-L
Secondary side ground voltage (however, V_T1And V_T2Virtual ground
Pressure). The in-phase detector 25X has two input signal voltages (V
_R1And V_R2), The in-phase of the phase relationship between
The output devices 25Y, 25C and 25L have two input signal voltages (V_R1
And V_R2, V_R1And V_S1, V_R2And V_S2Phase angle of 120 °
Detect delay (eg V_R1Against V_R2Is 120 ° late
It operates at this time).

As a result, the in-phase detector 25X can detect in-phase and out-of-phase on the power supply side and the load side of the distribution line bypass circuit 3, and the lag phase detectors 25C and 25L are the power supply side of the distribution line bypass circuit 3. , The phase sequence on the load side is the generator 1
It is possible to confirm whether it is in the same phase order as 6 and the lag phase detector 25Y
Is 120 on the power supply side and the load side of the distribution line bypass circuit 3.
° Phase lead and lag can be detected. Therefore, it is possible to confirm the phase sequence and the in-phase connection from 12 combinations of the operation patterns of the four detectors.

If the phase sequence and the in-phase connection are properly performed as described above, the power supply by the generator can be continued without any trouble, but the load carried by the generator increases due to various causes during the power supply. This causes a situation where stable power cannot be supplied due to lack of power generation capacity.To this end, it is necessary to promptly support a power supply vehicle with a generator of the same structure and connect in parallel to increase capacity. Often comes under pressure. At that time, it is necessary to ensure that the load is not biased toward one of the two generators and that the load is shared according to the output, and in order to maintain such balanced power supply. , Normally, a cross current compensator is provided in the generator side circuit to detect the cross current that occurs between the generators due to load deviation, etc., and automatically controls it so that it falls to the minimum value. However, reliable cross-current compensation cannot be performed unless one reference phase (for example, V phase) selected for cross-current detection from the three phases of the generator is connected so as to be in-phase between the two generators.

In this case, in the above-mentioned phase detector in the prior art, even if the phase sequence between the generator connected first and the generator to be supported later can be confirmed, A check for matching each reference phase (V phase) is impossible, and therefore, it is troublesome to rely on a live line connection by visual confirmation. Even so, if generators are placed close to each other, visual confirmation can be performed relatively easily.
In the case of a long distance, it is difficult to confirm the work and it takes a long time.

The present invention has been made in order to solve such a conventional problem, and an object of the present invention is to eliminate a standby power source generated by a generator from a commercial power source such as a high voltage distribution line. When connecting in parallel during a power outage, not only check the phase sequence and in-phase connection between the commercial power source and the generator, but also confirm the phase sequence and in-phase connection between the generators for parallel connection reliably and easily. An object of the present invention is to provide a phase detector for an uninterruptible power supply device that can perform.

[0010]

The present invention has the following configuration to achieve the above object. That is, the present invention provides a bypass circuit for a three-phase distribution line having a circuit breaker between a power source side and a load side, a reference phase and a three-phase AC generator having a predetermined phase sequence, and a circuit breaker. A main power supply device that is equipped with a three-phase distribution line power supply circuit that is connected to the load side of the electric wire bypass circuit and that is hot-connected to a single-phase or three-phase distribution line, and the reference phase and phase sequence have been determined. A power supply circuit for a three-phase power distribution line having a three-phase AC generator and a circuit breaker is provided, and the power supply circuit is installed side by side with the main power supply device and is live-connected to the power distribution line.
In the uninterruptible power supply device that is combined with the above base power supply device, each phase voltage of the ground standard of the distribution line that is provided in the main power supply device and is connected to the power supply side and the load side of the distribution line bypass circuit, respectively. The power supply side voltage detection means and the load side voltage detection means for detecting, and the phase voltage corresponding to the reference phase in the three-phase AC generator of the phase voltage detected by the load side voltage detection means is set to the reference phase voltage, Three-phase oscillating means for oscillating a ground-referenced three-phase voltage whose phase sequence matches that of the three-phase AC generator, and a power supply side voltage detecting means and an in-phase between corresponding phase voltages of the three-phase oscillating means are detected. Power supply side common mode detection means,
A load side common mode detecting means for detecting a common mode between phase voltages other than the reference phase voltage among the corresponding phase voltages of the three-phase oscillating means, and a phase sequence and a common phase connection And a load-side voltage detection means for detecting the phase voltage of the ground reference of the distribution line connected to the distribution line power supply circuit, which is provided in the main power supply device and the sub power supply device. And a phase voltage corresponding to a reference phase in the three-phase AC generator among the phase voltages detected by the load-side voltage detection means is set as a reference phase voltage, and the phase sequence matches with the three-phase AC generator. A three-phase oscillating means for oscillating a three-phase voltage of the ground reference, and an in-phase between the phase voltages other than the reference phase voltage among the corresponding phase voltages of the load side voltage detecting means and the three-phase oscillating means are detected. It is possible to confirm the phase sequence and in-phase connection by equipping the load side common mode detection means. And a reference phase voltage of the three-phase oscillator of the main power feeder and a reference of the three-phase oscillator of the slave power feeder. A generator-side common-mode detecting means for detecting the common-mode with the phase voltage is provided, so that the common-mode connection between both three-phase AC generators of the main power feeding device and the slave power feeding device can be confirmed.
A phase detector for an uninterruptible power supply device, comprising a phase detector for a sub power supply device.

[0011]

According to the present invention, a main power supply device includes a three-phase distribution line bypass circuit and a three-phase distribution line power supply circuit, and further includes a power supply side voltage detection means and a load. A phase detector for the main power supply device, which comprises side voltage detection means, three-phase oscillation means, power supply side in-phase detection means and load side in-phase detection means, and is capable of confirming the phase sequence and in-phase connection is provided. Further, the slave power supply device includes a power supply circuit for a three-phase distribution line, and further comprises a load-side voltage detection means, a three-phase oscillation means and a load-side in-phase detection means, and can confirm the phase sequence and in-phase connection. A phase detector for the slave power feeding device is provided. Further, the generator-side common-mode detecting means is provided for detecting the in-phase connection of the reference phase between the generators in association with the main power supply device and the slave power supply device. The procedure for connecting the main power supply device to the distribution line is the same as that of the prior art shown in FIG. 5, and when confirming the phase sequence and the in-phase connection, the two circuit breakers in this main power supply device should be left open. Using the three-phase voltage oscillated by the phase oscillating means as a reference, the power-supply side common-mode detecting means and the load-side common-mode detecting means make the three phases of the power supply side and load side of the bypass circuit for the distribution line the three-phase voltage. It can be easily confirmed by checking whether they match.

On the other hand, when the sub power supply device is connected in parallel to the main power supply device in response to an increase in load, the distribution line power supply circuit is connected to the distribution line with the breaker open. The generator-side common-mode detecting means confirms that the reference-phase common-mode connection is established, and then the load-side common-mode detecting means references the three-phase voltage oscillated by the three-phase oscillating means. It is checked whether all the phases on the load side of the bypass circuit for power supply match the three-phase voltage for all three phases, and by matching this, both phases including the phase sequence and the reference phase are correctly matched for both generators. It is possible to confirm that the parallel operation is possible in the normal state where the cross current compensation device is established. As described above, it is possible to easily and surely realize the phase detection performed for accurately connecting the main / slave power supply device to the uninterruptible power supply.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block circuit diagram when an uninterruptible power supply system according to an embodiment of the present invention is connected to a three-phase distribution line. The uninterruptible power supply system shown is the main power supply system 1
And one slave power feeding device 2. As the secondary power feeding device 2, not only one but a plurality of two or more may be used. The main power feeding device 1 is a bypass circuit for a three-phase distribution line having a circuit breaker 14 between three terminals R _1, S _1, T ₁ on the power source side and three terminals R _2, S _2, T ₂ on the load side. 3 and a three-phase AC generator 16 in which the reference phase (V phase) and the phase sequence are determined
A power supply circuit 4A for three-phase distribution line, which has A and a circuit breaker 15A and is connected to the load side of the bypass circuit 3 for distribution line, and a phase detector 11 for the main power supply device, which will be described later in detail, The distribution line 21 is hot-connected to the load side of the section switch 24.
In addition, as the reference phase in the three-phase AC generator 16A,
For example, the V-phase of the U-, V-, and W-phases in which the cross-current detection CT (not shown) of the cross-current compensator described above is provided is selected.

The sub power supply device 2 includes a three-phase power supply circuit 4B for a distribution line, which has a reference phase (V phase) and a three-phase AC generator 16B and a circuit breaker 15B whose phase sequence is determined. The power supply device phase detector 12 is provided and is hot-connected to the load side of the distribution switch 21 of the distribution line 21.

The phase detector 11 for the main power feeder is connected to the three terminals R _1, S _1, T ₁ on the power source side and the three terminals R _2, S _2, T ₂ on the load side in the bypass circuit 3 for distribution lines. It is possible to detect each ground-based phase voltage in the distribution line 21 and convert it into a low voltage, for example, an electrostatic circuit having a high-voltage or low-voltage capacitor as an element or a transformer circuit having an instrument transformer as an element. The power source side voltage detecting means 5 and the load side voltage detecting means 6A, and the phase voltage corresponding to the V phase in the three-phase AC generator 16A among the phase voltages detected by the load side voltage detecting means 6A is the reference phase. Three-phase oscillating means 7A that oscillates a ground-referenced three-phase voltage whose phase sequence matches that of the three-phase AC generator 16A, and R ₁₁ and S of the power supply side voltage detecting means 5.
_11, T ₁₁ The voltage of each phase and the corresponding R ₀ of the three-phase oscillator 7A _,
Power supply side common mode detecting means 8 comprising three common mode detectors 8 _R, 8 _S, 8 _T for detecting the common mode between the voltages of S ₀ (V phase) and T ₀
And two in-phase detectors 9A _R, which detect the in-phase between the R ₂₁ and T ₂₁ both-phase voltages of the load side voltage detecting means 6A and the corresponding R _{0 and} T ₀ both-phase voltages of the three-phase oscillating means 7A _. and a load-side phase detecting means 9A consisting 9A _T.

The slave power feeding device phase detector 12 detects the ground reference phase voltage in the distribution line 21 connected to the load side three terminals R _3, S _3, T ₃ of the distribution line feeding circuit 4B. Load side voltage detection means 6A capable of converting into a low voltage
The load side voltage detection means 6B having the same structure as the above, and the phase voltage corresponding to the V phase in the three-phase AC generator 16B among the phase voltages detected by the load side voltage detection means 6B is set as the reference phase voltage, Three-phase oscillating means 7B for oscillating a ground-referenced three-phase voltage whose phase sequence matches that of the three-phase AC generator 16B, and R ₃₁ and T ₃₁ both-phase voltages of the load side voltage detecting means 6B and the three-phase oscillating means. 7A includes a load-side common-mode detector 9B including two common-mode detectors 9B _{R and} 9B _T for detecting the common mode between the voltages of the corresponding R _{0 and} T ₀ phases.

Further, a phase detector 13 for main / slave power feeding device is provided in association with the main power feeding device 1 and the slave power feeding device 2. The phase detector 13 includes a V-phase signal output unit 17A provided on the main power feeding device 1 side, a V-phase signal output unit 17B provided on the slave power feeding device 2 side, and the main power feeding device 1 side or the sub power feeding device. The generator-side common-mode detecting means 10 realized by the common-mode detector provided on the second side is provided. The V-phase signal output unit 17A takes out the detection voltage of the S ₂₁ phase corresponding to the V-phase of the load side voltage detection unit 6A and outputs it as a V-phase signal, and the V-phase signal output unit 17A.
B takes out the detection voltage of the S ₃₁ phase corresponding to the V phase of the load side voltage detection means 6B and outputs it as a V phase signal. The in-phase detector 10 detects whether the signals from both V-phase signal output units 17A and 17B are in phase. Therefore, one connecting line 27 extending from the main power feeding device 1 to the sub power feeding device 2 is required for the in-phase detector 10. In the configuration described above, a known phase detector can be used as the eight in-phase detectors, and it is known that a delay / advance within a range of 40 ° ± 20 ° can be confirmed. ing.

Referring to FIG. 1 and FIG. 2 which is a functional explanatory diagram of the phase detector for the uninterruptible power supply system shown in FIG. Circuit breaker 1
4, 15A are opened together, and the power supply side terminal of the distribution line bypass circuit 3 is temporarily connected to the live line connecting portion 22 of the distribution line 21, and the load side terminal is similarly connected to the live line connecting portion 23. Then, an in-phase detector 8 _R, 8 forming the power supply side in-phase detecting means 8 is formed.
_The in-phase detector 8 _S of _{S and} 8 _T checks whether the V-phase voltage V _S0 of the three-phase oscillator 7 and the S _1- phase voltage V _S1 of the power supply side bypass circuit 3 are in phase, Match the connection at the power supply side terminal S ₁ up to twice to match the same phase. As a result, the power supply side terminal S ₁ and the load side terminal S ₂ (V phase) are correctly in phase. Then, in-phase detectors 8 _R, 8 _T
The in-phase of R ₁ (V _R1 ) and R ₀ (V _R0 ), T ₁ (V _T1 ) and T ₀ (V _T0 ) is checked by the connection between the power supply side terminals R ₁ and T ₁ at most once. Change to the same phase. Similarly, on the load side as well, R ₂ (V _R2 ) and R are provided by the in-phase detectors 9A _{R and} 9A _T forming the load-side in-phase detecting means 9A.
_{The in-} phase of ₀ (V _R0 ), T ₂ (V _T2 ) and T ₀ (V _T0 ) is examined, and the connection between the load side terminals R ₂ and T ₂ is adjusted to the same phase by one change at most.

When the phase sequence and the in-phase connection of the main power feeding device 1 are confirmed in this way, the bypass circuit 3 for distribution lines is used.
The power source side and the load side are in the same phase, and the phase order of the distribution line 21 and the three-phase AC generator 16A matches. Therefore, after the circuit breaker 14 is closed, the section switch 24 is opened to utilize the distribution line bypass circuit 3 to activate the three-phase AC generator 16A and the circuit breaker 4A makes a synchronous turn-on. After that, it is confirmed that the three-phase AC generator 16A has loaded a load, and the circuit breaker 14 is opened, whereby the live line connection of the main power supply device 1 is completed by making the temporary connection a main connection, and the section switch The loads after 24 are entirely fed by the three-phase AC generator 16A.

When the load carried by the main power supply device 1 increases and the main power supply device 1 cannot handle the power supply alone, it is necessary to operate the auxiliary power supply device 2 in parallel to increase the power supply. Becomes Therefore, by installing従給collector 2 in a location close to the section switch 25 of the distribution line 21, with open its breaker 15B, the load side terminal R ₃ of the power distribution line feeding circuit _4B, S _3, T ₃ is provisionally connected to the live line connecting portion 26 at the position after the section switch 25. Next, the connection line 27 is laid between the main power supply device 1 and the sub power supply device 1 and the required wiring connection is made, and the S ₂ phase of the main power supply device 1 and the sub power supply are made by the phase detector 13 for the main power supply device and the sub power supply device. Check the in-phase with the S ₃ phase of the device 2 and adjust to the in-phase by changing the connection at most twice.

Subsequently, R ₃ (V _R3 ) and R ₀ are supplied by the in-phase detectors 9B _{R and} 9B _T forming the load side in-phase detecting means 9B.
(V _R0 ), T ₃ (V _T3 ) and T ₀ (V _T0 ) are checked for the same phase, and the connection between the load side terminals R ₃ and T ₃ is adjusted to the same phase by one change at most. In this way, when the in-phase connection is confirmed based on the V phase of the secondary power feeding device 2,
V between the three-phase AC generator 16A and the three-phase AC generator 16B
It means that the phases and the phase sequence are correctly matched.
Therefore, by activating the three-phase AC generator 16B and causing the circuit breaker 4B to make a synchronous turn-on, the sub power feeding device 2 is
As the normal parallel operation starts, the cross current compensator also operates normally, and the three-phase AC generators 16A and 16B perform stable operation under a load sharing state according to the rated capacity.

FIG. 3 is a block circuit diagram when the uninterruptible power supply according to the embodiment of the present invention is connected to a single-phase distribution line, and FIG. 4 is a functional explanation of the phase detector for the uninterruptible power supply shown in FIG. It is a figure. The embodiment of FIG. 3 is similar to the power supply device shown in FIG. 1, and corresponding members are allotted with the same reference numerals. When connecting the uninterruptible device to the single-phase distribution line 23S, it is necessary to confirm which two phases of the three phases are used. Therefore, it is not necessary to confirm the phase sequence based on the standard of the three-phase power supply side of the substation. I have to. Therefore, the procedure of the phase detection in the main power feeding device 1 and the sub power feeding device 2 is basically the same as that shown in FIG.
The case where the S two phase is used and the T phase is made the open phase will be described as an example.

Regarding the main power feeding device 1 side, the power source side common mode detection
In-phase detector 8 forming output means 8_R,8_S,8_TSame of
Phase detector 8_SV phase voltage (V_S0) And S₁Phase voltage
(V _S1) Is in phase with the power supply side terminal S₁Connection
To be in phase with at most one change. This
The power supply side terminal S₁And load side terminal S_Two(V phase) is positive
The phases are in good agreement. Then, the in-phase detector 8_RBy
R₁(V_R1) And R₀(V_R0) Check the common mode of the power supply side
Terminal R₁, T₁Connection between at most one change
Match the same phase. Similarly, on the load side as well
In-phase detector 9A forming output means 9A_R,9A_TOf
In-phase detector 9A_RBy R_Two(V_R2) And R₀(V_R0)
Check the common mode of the load side terminal R_Two, T_TwoMany connections between
Adjust to at least one change in phase.

In this way, when the phase sequence and the in-phase connection of the main power supply device 1 are confirmed, the distribution line bypass circuit 3
The power source side and the load side are in the same phase, and the phase order of the distribution line 21S and the three-phase AC generator 16A matches. Therefore,
After closing the circuit breaker 14, the section switch 24 is opened, the bypass circuit 3 for distribution lines is utilized, the three-phase AC generator 16A is started, and the circuit breaker 4A makes a synchronous turn-on. After that, it is confirmed that the three-phase AC generator 16A carries a single-phase load, the circuit breaker 14 is opened, and thereby the live connection of the main power supply device 1 is completed by making the temporary connection the main connection.

On the side of the sub power feeding device 2, the connecting line 27 is extended between the main power feeding device 1 and the sub power feeding devices 1 and ₂ and the required wiring connection is made so that the voltage of the S ₂ phase (V _S2 ) of the main power feeding device 1 is increased. Then, the in-phase with the voltage of the S ₃ phase (V _S3 ) of the sub power feeding device 2 is checked by the phase detector 13 for the main and sub power feeding devices, and the same phase is adjusted by changing the connection at most twice. Then, the load side common mode detection means 9B
Phase detector to form a 9B _R, 9B _T-phase detector 9B _R
The in-phase of the voltage of R ₃ (V _R3 ) and the voltage of R ₀ (V _R0 ) is checked by and the connection between the load side terminals R ₃ and T ₃ is adjusted to the same phase by one change at most. In this way,
When the in-phase connection based on the V-phase of the slave power supply device 2 is confirmed, the three-phase AC generator 16A and the three-phase AC generator 16B.
This means that the mutual V-phase and phase order are correctly matched. Therefore, by starting the three-phase AC generator 16B and turning on the circuit breaker 4B synchronously, the slave power feeding device 2 enters normal parallel operation, and the cross current compensator also operates normally to generate three-phase AC power. Both the machines 16A and 16B perform stable operation under a load sharing state according to the rated capacity.

[0026]

As described above, according to the present invention, the main power feeding device and the sub power feeding device are provided with the three-phase oscillating means, whereby the three-phase alternating current generator of the detected voltage of the load side voltage detecting means is provided. The phase voltage corresponding to the reference phase is set as the reference phase voltage, and the ground-based three-phase voltage that matches the phase sequence with the three-phase AC generator is oscillated, and this three-phase voltage and the three-phase voltage of the distribution line Since the phases are checked so that the phases match each other, it is possible to confirm the phase sequence and the in-phase connection by using five in-phase detectors in the main power supply device and two in-phase detectors in the slave power supply device. Further, since the reference phase is confirmed by the single in-phase detector between the main power feeding device and the slave power feeding device, the reference phase of the three-phase alternating current generators, for example, the cross current detection phase, is matched with the same phase. You can connect. Therefore, it is possible not only to confirm the phase order / in-phase connection between the commercial power source and the generator, but also to confirm the phase order / in-phase connection between the generators for the parallel connection. By preventing cross current between generators and generators, uninterruptible power supply with excellent stability and reliability can be realized.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of a state in which an uninterruptible power supply system according to an embodiment of the present invention is connected to a three-phase distribution line.

FIG. 2 is a functional explanatory diagram of a phase detector for an uninterruptible power supply device shown in FIG.

FIG. 3 is a block circuit diagram showing a state in which the uninterruptible power supply system according to the embodiment of the present invention is connected to a single-phase distribution line.

4 is a functional explanatory diagram of a phase detector for an uninterruptible power supply system shown in FIG. 3. FIG.

FIG. 5 is a block circuit diagram showing a state in which a conventional uninterruptible power supply system is connected to a three-phase distribution line.

FIG. 6 is a functional explanatory diagram of the phase detector for the uninterruptible power supply device shown in FIG. 5.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Main electric power feeding device 2 ... Slave electric power feeding device 3 ... Distribution line bypass circuit 4A, 4B ... Distribution line feeding circuit 5 ... Power supply side voltage detection means 6A, 6B ... Load side voltage detection means 7A, 7B ... Three-phase oscillation means 8 ... Power source side in-phase detecting means 9A, 9B ... Load side in-phase detecting means 10 ... Generator side in-phase detecting means 11 ... Main power feeding device phase detector 12 ... Slave power feeding device phase detector 13 ... Main / slave power feeding device Phase detector 14, 15A, 15B ... Circuit breaker 16A, 16B ... Three-phase AC generator 21 ... Distribution line 27 ... Communication line

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000214560 Hasegawa Denki Kogyo Co., Ltd. 3-29-3 Obama-cho, Amagasaki-shi, Hyogo (72) Inventor Hiroki Mori 2-82 Watanabe-dori, Chuo-ku, Fukuoka-shi, Fukuoka No. Kyushu Electric Power Co., Inc. (72) Inventor Shunji Noma 1 2150 Shioido, Fukuma-cho, Munakata-gun, Fukuoka Prefecture Kyushu Transformer Co., Ltd. (72) Inventor Harada Mincho 140 Senzaga, Karatsu City, Saga Prefecture West Japan Power Generation Machine Co., Ltd. (72) Inventor Satoshi Fujiwara 329-3 Obama-cho, Amagasaki City, Hyogo Hasegawa Electric Co., Ltd. (72) Hiro Yamada 3-29-3 Obama-cho, Amagasaki City, Hyogo Prefecture Kawa Electric Industry Co., Ltd.

Claims (1)

[Claims] 1. A bypass circuit for a three-phase distribution line having a circuit breaker between a power supply side and a load side, a three-phase AC generator having a reference phase and a phase sequence, and a circuit breaker. Power supply circuit for a three-phase distribution line that is connected to the load side of a bypass circuit for power supply, and a main power supply device that is hot-connected to a single-phase or three-phase distribution line, and a three-phase system that determines the reference phase and phase sequence. A power supply circuit for a three-phase distribution line having a three-phase alternating current generator and a circuit breaker is provided, and the line is connected to the main power supply device and connected live to the distribution line.
In an uninterruptible power supply system that is combined with more than one secondary power supply system, each phase voltage of the ground standard of the distribution line installed in the main power supply system and connected to the power supply side and the load side of the distribution line bypass circuit, respectively. The power supply side voltage detection means and the load side voltage detection means for detecting, and the phase voltage corresponding to the reference phase in the three-phase AC generator of the phase voltage detected by the load side voltage detection means is set to the reference phase voltage, Three-phase oscillating means for oscillating a ground-referenced three-phase voltage whose phase sequence matches that of the three-phase AC generator, and a power supply side voltage detecting means and an in-phase between corresponding phase voltages of the three-phase oscillating means are detected. A power supply side common mode detection means, a load side voltage detection means, and a load side common mode detection means for detecting a common mode between phase voltage other than the reference phase voltage among the corresponding phase voltages of the three-phase oscillation means. , You can check the phase sequence and in-phase connection The phase detector for the main power supply device, the load side voltage detection means for detecting each phase voltage of the ground reference of the distribution line connected to the distribution line power supply circuit, and the load side Of the phase voltages detected by the voltage detecting means, a phase voltage corresponding to the reference phase in the three-phase AC generator is set as the reference phase voltage, and the three-phase ground reference phase matching the three-phase AC generator. Three-phase oscillating means for oscillating voltage,
The load-side voltage detection means and the load-side common-mode detection means for detecting an in-phase between phase voltages other than the reference phase voltage among the corresponding phase voltages of the three-phase oscillation means are provided, and the phase sequence and the in-phase The phase detector for the sub power supply device that can confirm the connection, and the reference phase voltage of the three-phase oscillating means of the main power supply device and the sub power supply device that are provided in association with the main power supply device and the sub power supply device. The generator-side common-mode detecting means for detecting the same phase with the reference-phase voltage of the three-phase oscillating means is provided so that the common-mode connection between the three-phase alternating current generators of the main power feeding device and the slave power feeding device can be confirmed. A phase detector for an uninterruptible power supply, which includes a phase detector for a main power supply and a slave power supply.