Power supply system switching device and power supply system switching method

Abstract

This power supply system switching device for switching a power supply system from a power supply apparatus, comprising: a plurality of first circuit breakers that interrupt current in a first system and cancel interruption of current in a second system; an optical modulator that modulates incident light and emits the modulated light on the basis of a voltage applied in proportion to the current detected by the plurality of first circuit breakers; a modulation detector that detects the modulation of incident light from the optical modulator; and a plurality of second circuit breakers that, when the modulation detector detects the modulation, interrupt the current in the first system and cancel the interruption of current in the second system.

Description

[Technical field]

[0001] The present invention relates to a power supply system switching device and a power supply system switching method. [Background technology]

[0002] In the event of a short circuit in a power supply system, it is common to immediately isolate the fault point using a wiring circuit breaker that automatically cuts off the circuit, and the accident can be minimized by quickly detecting the short circuit and isolating it. Furthermore, by preparing multiple power supply systems for the equipment, even if one system is cut off due to an accident such as a short circuit, the impact of the power supply to the equipment being cut off can be reduced by switching to another system.

[0003] There is also known a technique that uses a circuit breaker with a fast interruption action. For example, Patent Document 1 discloses a direct current circuit breaker that performs switching using a semiconductor circuit breaker with a fast interruption action. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-011933 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, with conventional technology, switching between systems requires controlling the opening and closing of multiple circuit breakers. Although the shutoff operation itself is fast, controlling the operation of multiple circuit breakers and switching systems incurs time losses, which can result in momentary voltage drops.

[0006] The disclosed technology aims to reduce time loss caused by controlling the operation of multiple circuit breakers. [Means for solving the problem]

[0007] The disclosed technology is a power supply system switching device for switching a power supply system from a power supply device, the power supply system switching device including: a first plurality of circuit breakers that cut off the current of a first system and release the cut-off of the current of a second system; an optical modulator that modulates and emits incident light based on a voltage applied in proportion to the current detected by the first plurality of circuit breakers; a modulation detector that detects modulation of the light incident from the optical modulator; and a second plurality of circuit breakers that cut off the current of the first system and release the cut-off of the current of the second system when the modulation detector detects the modulation. Effect of the Invention

[0008] It is possible to reduce the time loss involved in controlling the operation of a plurality of circuit breakers. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a first diagram showing an example of the configuration of a conventional power supply system switching device. [Diagram 2] FIG. 11 is a second diagram showing an example of the configuration of a conventional power supply system switching device. [Diagram 3] 1 is a diagram illustrating an example of a configuration of a power supply system switching device according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram illustrating an example of the configuration of a semiconductor circuit breaker. [Diagram 5] FIG. 2 is a first diagram illustrating an example of an operation of the power supply system switching device according to the embodiment of the present invention. [Figure 6] FIG. 11 is a second diagram illustrating an example of an operation of the power supply system switching device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention (the present embodiment) will be described with reference to the drawings. The embodiment described below is merely an example, and the embodiment to which the present invention is applied is not limited to the following embodiment. Before describing the technology related to the present embodiment, the conventional technology related to the present embodiment and its problems will be described first.

[0011] (Regarding the Prior Art) Fig. 1 is a first diagram showing an example of the configuration of a conventional power supply system transfer device. The conventional power supply system transfer device is composed of a plurality of circuit breakers 90a, 90b, 90c, and 90d. As shown in Fig. 1, the power supply system transfer device is configured to have a circuit breaker only on the positive power cable 40a, but a similar circuit breaker may also be provided on the negative power cable 40b.

[0012] The DC power supplied from the power supply device 10 to the load device 20 is supplied through two systems, system 1 and system 2. Under normal circumstances, power is supplied through system 1, and if an accident such as a short circuit occurs in system 1, it is switched to system 2.

[0013] Specifically, when an accident such as a short circuit occurs at the fault point 41 and the occurrence of the accident is detected by the circuit breaker 90a, the circuit breaker 90a is opened and the circuit breaker 90b is closed. Note that opening is an operation to interrupt the current, and closing is an operation to release the interruption of the current. Next, the circuit breaker 90c is opened and the circuit breaker 90d is closed.

[0014] At this time, it may take time for the circuit breaker to operate, causing an instantaneous voltage drop, which may result in a malfunction of the load device 20, such as stopping the load device 20.

[0015] Fig. 2 is a second diagram showing an example of the configuration of a conventional power supply system switching device. The power supply system switching device shown in Fig. 2 includes a plurality of semiconductor circuit breakers 30a, 30b, 30c, and 30d. In the case of a semiconductor circuit breaker, the breaker speed of a single unit is fast, but the semiconductor circuit breaker 30a that detects the occurrence of an accident detects a short circuit current, converts the detection of the short circuit current into an electrical signal (or an optical signal), transmits the electrical signal to the semiconductor circuit breakers 30c and 30d, the semiconductor circuit breakers 30c and 30d receive the electrical signal (or an optical signal), analyzes the received signal that the semiconductor circuit breaker 30a has detected a short circuit current, and operates the semiconductor circuit breakers 30c and 30d. Since it may take time to convert and transmit / receive signals for switching instructions, time loss is not sufficiently suppressed.

[0016] Fig. 3 is a diagram showing an example of the configuration of a power supply system switching device according to the present embodiment. The power supply system switching device 1 according to the present embodiment includes semiconductor circuit breakers 30a, 30b, 30c, and 30d similar to those in Fig. 2, and further includes an optical modulator 50 and a modulation detector 60.

[0017] The optical modulator 50 modulates the light emitted from the light source 70 toward the light receiving unit 80 when an occurrence of an accident is detected in the semiconductor circuit breaker 30a or the semiconductor circuit breaker 30b.

[0018] The modulation detector 60 detects modulation of the light emitted from the light source 70 toward the light receiving unit 80. When the modulation detector 60 detects modulation, the semiconductor circuit breaker 30c and the semiconductor circuit breaker 30d switch between an open state and a closed state.

[0019] Fig. 4 is a diagram showing an example of the configuration of a semiconductor circuit breaker. The semiconductor circuit breaker 30 shown in Fig. 4 has a configuration common to semiconductor circuit breakers 30a, 30b, 30c, and 30d.

[0020] The semiconductor circuit breaker 30 includes a control circuit 31, an IGBT (Insulated Gate Bipolar Transistor) 32, a voltage suppression circuit 33, and a current sensor .

[0021] The control circuit 31 controls the opening and closing of the IGBT 32 via a control line 35. Although the IGBT 32 is shown as having a built-in power supply in FIG.

[0022] The IGBT 32 is an insulated gate bipolar transistor, and under the control of the control circuit 31, cuts off the current flowing through the positive power cable 40a or releases the cutoff of the current.

[0023] The voltage suppression circuit 33 is a capacitor or a diode, etc., and is a circuit that suppresses a rise in voltage occurring between the positive power cable 40a and the negative power cable 40b. The two voltage suppression circuits 33 connected to both ends of the IGBT 32 can prevent a sudden rise in voltage due to current interruption.

[0024] The current sensor 34 measures the value of the current flowing through the power cable 40a, and transmits a signal indicating the current value to the control circuit 31. In this way, the control circuit 31 detects the occurrence of a short-circuit current.

[0025] When a semiconductor circuit breaker is installed on the negative electrode side, the power cable 40a in FIG. 4 should be read as the negative electrode side, and the power cable 40b as the positive electrode side.

[0026] FIG. 5 is a first diagram illustrating an example of the operation of the power supply system switching device according to the embodiment of the present invention.

[0027] First, the configurations of the optical modulator 50 and the modulation detector 60 will be described. The optical modulator 50 includes a polarizer 51 and electro-optic crystals 52a and 52b. The polarizer 51 polarizes the light incident from the light source 70 in a certain direction. The electro-optic crystals 52a and 52b are elements for changing the polarization direction of the light by applying a voltage.

[0028] The modulation detector 60 includes half mirrors 61c and 61d, analyzers 62c and 62d, and O / E converters 63c and 63d. The half mirrors 61c and 61d are mirrors that reflect a part of the incident light toward the analyzers 62c and 62d and transmit a part of the light. The analyzers 62c and 62d are elements for detecting the presence or absence of polarization and the direction of the polarization plane. The O / E converters 63c and 63d are devices that convert optical signals into electrical signals.

[0029] The semiconductor circuit breaker 30a and the semiconductor circuit breaker 30b, and the semiconductor circuit breaker 30c and the semiconductor circuit breaker 30d are communicatively connected to each other via a connection line 42. The optical modulator 50 and the modulation detector 60 are connected to each other by a polarization-maintaining fiber 43.

[0030] Next, a description will be given of the operation of the power supply system switching device 1. When power is being supplied from system 1, a short circuit occurs at a fault point between semiconductor circuit breaker 30a and semiconductor circuit breaker 30c (step S11), and semiconductor circuit breaker 30a detects the short circuit (step S12).

[0031] The semiconductor circuit breaker 30a controls the IGBT 32 by the control circuit 31 to cut off the current in the system 1 (step S13), and also transmits a signal to the semiconductor circuit breaker 30b via the interconnection line 42 (step S14). The semiconductor circuit breaker 30b that receives the signal releases the cutoff of the current in the system 2. This causes the switching operation of the semiconductor circuit breaker 30a and the semiconductor circuit breaker 30b to be performed instantly.

[0032] Next, when the semiconductor circuit breaker 30a cuts off the current in system 1, the voltage V 1 is applied to electro-optic crystal 52a (step S15), and the plane of polarization of the linearly polarized wave incident from light source 70 is rotated by, for example, +45 degrees (step S16).

[0033] The light emitted from the optical modulator 50 enters the modulation detector 60 via the polarization-maintaining fiber 43. If the light has a polarization plane rotated by +45 degrees, it is reflected by the half mirror 61c and enters the analyzer 62c. When the analyzer 62c detects the incident light, the O / E converter 63c converts the optical signal into an electrical signal (step S17).

[0034] The semiconductor circuit breaker 30c receives the converted electrical signal, controls the IGBT 32 by the control circuit 31, cuts off the current in the system 1 (step S18), and also transmits a signal to the semiconductor circuit breaker 30d via the interconnection line 42 (step S19). The semiconductor circuit breaker 30d that receives the signal releases the cutoff of the current in the system 2. As a result, the switching operation of the semiconductor circuit breaker 30c and the semiconductor circuit breaker 30d is performed instantly, and the switching from the system 1 (an example of a first power supply system) to the system 2 (an example of a second power supply system) is completed.

[0035] 6 is a second diagram showing an example of the operation of the power supply system switching device according to the embodiment of the present invention. When power is being supplied from system 2, a short circuit occurs at the fault point between semiconductor circuit breaker 30b and semiconductor circuit breaker 30d (step S21), and semiconductor circuit breaker 30b detects the short circuit (step S22).

[0036] The semiconductor circuit breaker 30b controls the IGBT 32 by the control circuit 31 to cut off the current in the system 2 (step S23) and also transmits a signal to the semiconductor circuit breaker 30a via the interconnection line 42 (step S24). The semiconductor circuit breaker 30a that receives the signal releases the cutoff of the current in the system 1. This causes the switching operation of the semiconductor circuit breaker 30a and the semiconductor circuit breaker 30b to be performed instantaneously.

[0037] Next, when the semiconductor circuit breaker 30b cuts off the current in system 2, the voltage V 2 is applied to electro-optic crystal 52b (step S25), and the plane of polarization of the linearly polarized wave incident from light source 70 is rotated, for example, by −45 degrees (step S26).

[0038] The light emitted from the optical modulator 50 enters the modulation detector 60 via the polarization-maintaining fiber 43. If the light has a polarization plane rotated by -45 degrees, it is reflected by the half mirror 61d and enters the analyzer 62d. When the analyzer 62d detects the incident light, the O / E converter 63d converts the optical signal into an electrical signal (step S27).

[0039] The semiconductor circuit breaker 30d receives the converted electrical signal, controls the IGBT 32 by the control circuit 31, cuts off the current in the system 2 (step S28), and also transmits a signal to the semiconductor circuit breaker 30c via the interconnection line 42 (step S29). The semiconductor circuit breaker 30c that has received the signal releases the cutoff of the current in the system 1. As a result, the switching operation of the semiconductor circuit breaker 30c and the semiconductor circuit breaker 30d is performed instantly, and the switching from the system 2 (an example of a first power supply system) to the system 1 (an example of a second power supply system) is completed.

[0040] According to the power supply system switching device 1 of this embodiment, the light modulated by the optical modulator 50 connected to the first plurality of circuit breakers (semiconductor circuit breakers 30a, 30b) is detected by the modulation detector 60 connected to the second plurality of circuit breakers (semiconductor circuit breakers 30c, 30d). As a result, in the transmission of information from the first plurality of circuit breakers (semiconductor circuit breakers 30a, 30b) to the second plurality of circuit breakers (semiconductor circuit breakers 30c, 30d), the first plurality of circuit breakers detect a short circuit current and modulate the light at the same time, so that the information that the first plurality of circuit breakers have detected a short circuit current can be transmitted to the second plurality of circuit breakers based on whether the light is modulated or not without converting the information into an electrical signal (or an optical signal) (without using a communication protocol). This makes it possible to suppress time loss, such as converting the information that the short circuit current has been detected into an electrical signal (or an optical signal), converting the electrical signal so that it can be transmitted over an IP network, for example, and converting the electrical signal into a signal that controls the circuit breaker on the receiving side of the signal. This makes it possible to instantly switch between multiple power supply systems.

[0041] The voltage V mentioned above 1 and voltage V 2may be a voltage value generated when the current sensor 34 detects a current, or may be a voltage value obtained by increasing or decreasing the voltage value generated by the current sensor 34.

[0042] The configurations of the optical modulator 50 and modulation detector 60 shown in this embodiment are merely examples, and any other optical modulation technology that modulates light with voltage and modulation detection technology that detects the modulated light may be used.

[0043] The semiconductor circuit breakers 30a, 30b, 30c, and 30d are examples of circuit breakers. The circuit breaker may be an electronic switch or an electrically controllable breaker.

[0044] (Summary of the embodiment) This specification describes at least the power supply system switching devices and power supply system switching methods described in the following sections. (Section 1) A power supply system switching device for switching a power supply system from a power supply device, a first plurality of circuit breakers that interrupt a current in a first system and release the interruption of a current in a second system; an optical modulator that modulates and emits incident light based on a voltage that is applied in proportion to the current detected by the first plurality of circuit breakers; a modulation detector for detecting modulation of light incident from the optical modulator; and a second plurality of circuit breakers that interrupt the current of the first system and release the interruption of the current of the second system when the modulation detector detects modulation. Power supply system switching device. (Section 2) Each of the first plurality of breakers includes a control circuit, an IGBT, and a current sensor; When the control circuit detects the occurrence of a short circuit current by the current sensor, it controls the IGBT to cut off the current in the first system.

[0045] 2. The power supply system switching device according to claim 1. (Section 3) Each of the first plurality of circuit breakers is communicatively connected to each other via a connection line, and when any one of the circuit breakers included in the first plurality of circuit breakers detects a current, the circuit breaker transmits a signal to the other circuit breakers included in the first plurality of circuit breakers via the connection line. 3. The power supply system switching device according to claim 1 or 2. (Section 4) Each of the second plurality of circuit breakers is communicatively connected to one another via a tie line, and when any one of the circuit breakers included in the second plurality of circuit breakers receives a signal from the modulation detector, the circuit breaker transmits a signal to the other circuit breakers included in the second plurality of circuit breakers via the tie line. 4. A power supply system switching device according to any one of claims 1 to 3. (Section 5) A power supply system switching method executed by a power supply system switching device for switching a power supply system from a power supply device, comprising: interrupting the current of the first system and canceling the interruption of the current of the second system; modulating and emitting the incident light based on a voltage applied in proportion to the detected current; detecting a modulation of the incident light; and when the modulation is detected, interrupting the current of the first system and canceling the interruption of the current of the second system. Power supply system switching method.

[0046] Although the present embodiment has been described above, the present invention is not limited to such a specific embodiment, and various modifications and variations are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0047] 1. Power supply switching device 10 Power supply 20 Load device 30 Semiconductor circuit breaker 31 Control circuit 32 IGBT 33 Voltage suppression circuit 34 Current Sensor 35 Control Line 40 Power Cable 41 Accident points 42 Connection Line 43 Polarization-maintaining fiber 50 Optical Modulator 51 Polarizer 52 Electro-optical crystals 60 Modulation Detector 61 Half Mirror 62 Analyzer 63 O / E converter 70 light source 80 Light receiving section 90 Circuit Breaker

Claims

1. A power supply system switching device for switching a power supply system from a power supply device, a first plurality of circuit breakers that interrupt a current in a first system and release the interruption of a current in a second system; an optical modulator that modulates and emits incident light based on a voltage that is applied in proportion to the current detected by the first plurality of circuit breakers; a modulation detector for detecting modulation of light incident from the optical modulator; and a second plurality of circuit breakers that interrupt the current of the first system and release the interruption of the current of the second system when the modulation detector detects modulation. Power supply system switching device.

2. Each of the first plurality of breakers includes a control circuit, an IGBT, and a current sensor; When the control circuit detects the occurrence of a short circuit current by the current sensor, it controls the IGBT to cut off the current in the first system. The power supply system switching device according to claim 1 .

3. Each of the first plurality of circuit breakers is communicatively connected to each other via a connection line, and when any one of the circuit breakers included in the first plurality of circuit breakers detects a current, the circuit breaker transmits a signal to the other circuit breakers included in the first plurality of circuit breakers via the connection line. The power supply system switching device according to claim 1 or 2.

4. Each of the second plurality of circuit breakers is communicatively connected to one another via a tie line, and when any one of the circuit breakers included in the second plurality of circuit breakers receives a signal from the modulation detector, the circuit breaker transmits a signal to the other circuit breakers included in the second plurality of circuit breakers via the tie line. The power supply system switching device according to any one of claims 1 to 3.

5. A power supply system switching method executed by a power supply system switching device for switching a power supply system from a power supply device, comprising: interrupting the current of the first system and canceling the interruption of the current of the second system; modulating and emitting the incident light based on a voltage applied in proportion to the detected current; detecting a modulation of the incident light; and when the modulation is detected, interrupting the current of the first system and canceling the interruption of the current of the second system. Power supply system switching method.

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