Excitation rush current suppressing circuit system

Abstract

To realize reduction of a setting burden and reduction of a cost, etc. by connecting a grid-side breaker and a transformer-side breaker in series to an electric path between a grid and a transformer and connecting a suppression resistor in parallel with the transformer-side breaker.SOLUTION: An excitation rush current suppressing circuit system 1 has a breaker 2 and a suppression resistor 3 connected between a grid K and a transformer H. A grid-side breaker 2a and a transformer-side breaker 2b included in the breaker 2 are connected in series, and the suppression resistor 3 is connected in parallel with the transformer-side breaker 2b. Also, an introducing order of the grid-side breaker 2a and the transformer-side breaker 2b is defined in such a way that the grid-side breaker 2a is first introduced and then the transformer-side breaker 2b is introduced. If the transformer-side breaker 2b is not introduced after elapse of a prescribed time from the introduction of the grid-side breaker 2a, the grid-side breaker 2a may be cut off.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a magnetizing inrush current suppression circuit system having a circuit breaker and a suppression resistor connected to an electric path between a power grid and a transformer. [Background technology]

[0002] Conventionally, when a transformer is connected to a power system, a magnetizing inrush current several tens of times the rated current of the transformer flows, and then the transformer reaches a steady state. To address this problem, a gas circuit breaker equipped with a magnetizing inrush current suppression device has been known (see Patent Document 1). This gas circuit breaker with an excitation inrush current suppression device comprises a first gas circuit breaker consisting of a grounded tank filled with insulating gas, fixed contacts and movable contacts arranged in the tank, and bushings attached to the tank and connected to the fixed contacts and movable contacts, respectively, and a second gas circuit breaker consisting of a grounded tank filled with insulating gas, fixed contacts and movable contacts arranged in the tank, and bushings attached to the tank and connected to either the fixed contact or the movable contact via an inrush current limiting resistor, and power is supplied to a transformer via a parallel circuit of the first and second gas circuit breakers. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2002-075145 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, as described in paragraph 0010 of Patent Document 1, the gas circuit breaker with magnetizing inrush current suppression device described therein is premised on the reuse of an existing three-phase circuit breaker and is intended primarily for single-phase transformers. Therefore, when intended for use with a three-phase transformer, it is necessary to install a separate circuit breaker, making it difficult to accommodate changes in the number of transformer phases, and there are problems in that the work of installing a separate circuit breaker increases the burden and incurs additional costs, such as the installation costs.

[0005] In consideration of these points, the present invention aims to provide a magnetizing inrush current suppression circuit system that can achieve "reduction in installation burden and cost" regardless of the number of transformer phases by connecting a system-side circuit breaker and a transformer-side circuit breaker in series in the electric circuit between the system and the transformer, and connecting a suppression resistor in parallel with the transformer-side circuit breaker. [Means for solving the problem]

[0006] The suppression circuit system 1 of the present invention is a suppression circuit system having a circuit breaker 2 and a suppression resistor 3 connected to an electric path between a system K and a transformer H, and has a first feature in that the circuit breaker 2 includes a system side circuit breaker 2a and a transformer side circuit breaker 2b, the system side circuit breaker 2a and the transformer side circuit breaker 2b are connected in series in the electric path between the system K and the transformer H, and the suppression resistor 3 is connected in parallel with the transformer side circuit breaker 2b across the electric path between the system side circuit breaker 2a and the transformer side circuit breaker 2b and the electric path between the transformer side circuit breaker 2b and the transformer H.

[0007] A second feature of the suppression circuit system 1 of the present invention, in addition to the first feature described above, is that the order of closing the system side circuit breaker 2a and the transformer side circuit breaker 2b is that the system side circuit breaker 2a is closed first and then the transformer side circuit breaker 2b is closed.

[0008] A third feature of the suppression circuit system 1 of the present invention, in addition to the second feature described above, is that when the system side circuit breaker 2a and the transformer side circuit breaker 2b are closed, if the transformer side circuit breaker 2b has not been closed even after a predetermined time has elapsed since the system side circuit breaker 2a was closed, the system side circuit breaker 2a is shut off.

[0009] Due to these features, by connecting the system side circuit breaker 2a and the transformer side circuit breaker 2b included in the circuit breaker 2 in series and connecting the suppression resistor 3 in parallel with the transformer side circuit breaker 2b, unlike Patent Document 1, it is not assumed that an existing three-phase circuit breaker will be reused, and it is compatible with transformers H of any number of phases (three-phase, single-phase, etc.), so there is no need to install another circuit breaker, and therefore there is no increase in the burden due to the installation work of a separate circuit breaker, and no extra costs such as installation expenses are incurred ("reduction of installation burden / cost"). The suppression circuit system 1 can also be said to be a "magnetizing inrush current suppression circuit system."

[0010] Furthermore, the order of closing the system-side circuit breaker 2a and the transformer-side circuit breaker 2b may be such that the system-side circuit breaker 2a is closed first and the transformer-side circuit breaker 2b is closed second. Here, after the suppression circuit system 1 is installed, the circuit breaker 2 is opened and closed once or several times over a long period (several years to several decades, etc.). Therefore, even if attempts are made to close each of the circuit breakers 2a and 2b, if the transformer side circuit breaker 2b cannot be closed for some reason (such as a malfunction), a large current from system K will flow through the suppression resistor 3, causing the suppression resistor 3 to overheat, which may result in melting or catching fire. Therefore, if the transformer side circuit breaker 2b has not been closed even after a predetermined time has elapsed since the system side circuit breaker 2a was closed, the system side circuit breaker 2a is shut off, so that the large current from system K can be stopped from flowing to the suppression resistor 3 before the suppression resistor 3 generates excessive heat and melts or catches fire, etc., thereby achieving "improved safety." Effect of the Invention

[0011] According to the suppression circuit system of the present invention, by connecting the system side circuit breaker and the transformer side circuit breaker in series in the electric circuit between the system and the transformer, and connecting the suppression resistor in parallel with the transformer side circuit breaker, it is possible to achieve "reduction in installation burden and cost," etc. [Brief description of the drawings]

[0012] [Figure 1] 1 is a circuit diagram showing an overview of a suppression circuit system according to the present invention; [Diagram 2] FIG. 1 is a circuit diagram illustrating an example of an outline of a suppression circuit system, in which there is one transformer and one panel housing in one plant. [Diagram 3] FIG. 1 is a circuit diagram illustrating an example of an outline of a suppression circuit system, in which a single plant has a plurality of transformers and panel housings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. <Overall configuration of suppression circuit system 1> As shown in Figures 1 to 3, the suppression circuit system 1 of the present invention is a system connected to an electric circuit between a system K and a transformer H (hereinafter also referred to as the "system-transformer electric circuit 4"), and has a circuit breaker 2 described later and a suppression resistor 3 described later. The suppression circuit system 1 may include a control device 10, which will be described later. In addition, the suppression circuit system 1 can be said to have at least a part of the system-transformer electric circuit 4 (such as the circuit breaker electric circuit 4b and the circuit breaker-transformer electric circuit 4c described later). The suppression circuit system 1 may be provided inside a predetermined panel housing B, which will be described later. The closing (energization) of the breaker 2 in the suppression circuit system 1 will be described later.

[0014] Here, the current, interrupting current, voltage, power, and capacity in the present invention may be values ​​within a rated range, in which case they can be referred to as rated current, rated interrupting current, rated voltage, rated power, and rated capacity. These rated currents, etc. can be said to be limit values ​​of power, etc. guaranteed by the manufacturer to ensure the safe use of electrical appliances, and further, ratings can be said to be the usage limits or conditions that guarantee the safe and proper operation of devices and equipment. Furthermore, when the current in the present invention is alternating current, the current value (current value), the interrupting current value (interrupting current value), the voltage value (voltage value), the power value (power value), and the capacity value (capacity value) may be effective values.

[0015] <Circuit Breaker 2> As shown in Figures 1 to 3, the circuit breaker 2 is connected to an electric circuit (system-transformer electric circuit 4) between the system K and the transformer H, and is a device capable of interrupting the system-transformer electric circuit 4, and includes a system-side circuit breaker 2a and a transformer-side circuit breaker 2b, which will be described later. The circuit breaker 2 may include one or more other circuit breakers (e.g., child circuit breaker B9 in Figure 3) in addition to the system side circuit breaker 2a and the transformer side circuit breaker 2b in the system-transformer electric circuit 4, but the circuit breaker 2 in one suppression circuit system 1 may consist only of the system side circuit breaker 2a and the transformer side circuit breaker 2b. The specific configuration of these circuit breakers 2 is not particularly limited, but may be, for example, a vacuum circuit breaker (VCB, Vacuum Circuit Breaker), an air circuit breaker (ACB, Air Circuit Breaker), a molded case circuit breaker (MCCB, Molded Case Circuit Breaker), or an earth leakage circuit breaker (ELCB, Earth Leakage Circuit Breaker).

[0016] The circuit breaker 2 may be closed by an electric spring operation, or may be closed by a signal from the control device 10 described later, or may be closed remotely via a communication device such as the Internet or a telephone line, or may be closed manually on-site via the control device 10 (or directly), or may output a signal (answerback signal) indicating that the circuit breaker has been closed to the control device 10 when the circuit breaker is closed. Also, the circuit breaker 2 may be equipped with contacts for minute currents. In the following description, the system-side circuit breaker 2a and the transformer-side circuit breaker 2b will be mainly described as vacuum circuit breakers.

[0017] The rated current of these circuit breakers 2 is not particularly limited, and may be, for example, 400A, 600A, or 630A, or 1A to 5000A, preferably 10A to 3000A, and more preferably 100A to 2000A. The rated interrupting current of these circuit breakers 2 is not particularly limited, but may be, for example, 8.0 kA or 12.5 kA, or may be 0.1 kA or more and 1000.0 kA or less, preferably 0.5 kA or more and 500.0 kA or less, and more preferably 1.0 kA or more and 100.0 kA or less, and the current that actually flows as the magnetizing inrush current may be 18 A, for example. The rated voltage of these circuit breakers 2 is not particularly limited, and may be, for example, 7.2 kV or 3.6 kV, or may be 0.1 kV to 500.0 kV, preferably 0.5 kV to 100.0 kV, and more preferably 1.0 kV to 50.0 kV.

[0018] <System side circuit breaker 2a, transformer side circuit breaker 2b, etc.> As shown in Figures 1 to 3, the system-side circuit breaker 2a is the circuit breaker closer to system K among the above-mentioned circuit breakers 2, and the transformer-side circuit breaker 2b is the circuit breaker closer to transformer H among the above-mentioned circuit breakers 2. In more detail, the system-side circuit breaker 2a may be a circuit breaker connected at least closer to the system K than the transformer-side circuit breaker 2b in the electric circuit between the system K and the transformer H (system-transformer electric circuit 4), and may be a circuit breaker connected closest to the system K. On the other hand, the transformer-side circuit breaker 2b may be a circuit breaker connected at least closer to the transformer H than the system-side circuit breaker 2a in the system-transformer electric circuit 4, and may be a circuit breaker connected closest to the transformer H. The system-side circuit breaker 2a and the transformer-side circuit breaker 2b are connected in series in the system-transformer electric circuit 4, and the transformer-side circuit breaker 2b is connected in parallel with the suppression resistor 3 (described later).

[0019] As described above, if the circuit breaker 2 includes another circuit breaker in addition to the system side circuit breaker 2a and the transformer side circuit breaker 2b, this other circuit breaker may also be connected in series with the system side circuit breaker 2a and the transformer side circuit breaker 2b in the system-transformer electric circuit 4. In this case, the position where the other circuit breaker is connected is not particularly limited, and may be, for example, the electric circuit between the system K and the system side circuit breaker 2a (hereinafter also referred to as the "system-to-circuit breaker electric circuit 4a"), the electric circuit between the system side circuit breaker 2a and the transformer side circuit breaker 2b (hereinafter also referred to as the "inter-circuit breaker electric circuit 4b"), or the electric circuit between the transformer side circuit breaker 2b and the transformer H (hereinafter also referred to as the "circuit breaker-to-transformer electric circuit 4c"). In particular, in the inter-circuit breaker electric circuit 4b, no other equipment such as another circuit breaker may be connected, and there may only be a branch point (inter-circuit breaker branch point) 5b to the suppression resistor 3 described later. In the following description, it is assumed that the circuit breakers 2 in one suppression circuit system 1 mainly consist of only the system-side circuit breaker 2a and the transformer-side circuit breaker 2b.

[0020] Regarding the order (closing sequence) of closing the system-side circuit breaker 2a and the transformer-side circuit breaker 2b described above, the system-side circuit breaker 2a may be closed first, and the transformer-side circuit breaker 2b may be closed later. In this case, the time difference between closing the system side circuit breaker 2a and closing the transformer side circuit breaker 2b is not particularly limited, but may be, for example, 0.02 seconds, or 0.001 seconds or more and 5,000 seconds or less, preferably 0.005 seconds or more and 1.000 seconds or less, and more preferably 0.010 seconds or more and 0.500 seconds or less. The order in which the system-side circuit breaker 2a and the transformer-side circuit breaker 2b are turned on may be controlled by a control device 10, which will be described later.

[0021] In addition, when the system side circuit breaker 2a and the transformer side circuit breaker 2b are closed, if a predetermined time has elapsed since the system side circuit breaker 2a was closed but the transformer side circuit breaker 2b has not been closed, the system side circuit breaker 2a may be shut off. In this case, the above-mentioned predetermined time is not particularly limited, but may be, for example, 2 seconds, or 0.01 to 10.00 seconds, preferably 0.05 to 8.00 seconds, and more preferably 0.10 to 5.00 seconds. In addition, when the transformer side circuit breaker 2b is not closed even after a predetermined time has elapsed after the system side circuit breaker 2a is closed, the shutoff of the system side circuit breaker 2a may also be controlled by the control device 10 described later.

[0022] <Suppression resistance 3> As shown in FIGS. 1 to 3, the suppression resistor 3 is a resistor connected to an electric path between the system K and the transformer H (system-transformer electric path 4), and may be an overcurrent limiting resistor or the like. The suppression resistor 3 is connected in parallel with the transformer side circuit breaker 2b across the electrical path (inter-circuit breaker electrical path 4b) between the above-mentioned system side circuit breaker 2a and the transformer side circuit breaker 2b, and the electrical path (inter-circuit breaker electrical path 4c) between the transformer side circuit breaker 2b and the transformer H. To explain in detail the parallel connection with the transformer side circuit breaker 2b, the suppression resistor 3 is connected to an electric circuit extending from the inter-circuit breaker branch point 5b of the inter-circuit breaker circuit 4b to the inter-circuit breaker-transformer branch point 5c of the inter-circuit breaker-transformer circuit 4c (which can also be referred to as the electric circuit between the inter-circuit breaker branch point 5b and the inter-circuit breaker-transformer branch point 5c, hereinafter also referred to as the "resistance circuit 4d").

[0023] The resistance value of the suppression resistor 3 is not particularly limited, and may be, for example, 300Ω or 500Ω, or may be 10Ω or more and 5000Ω or less, preferably 50Ω or more and 3000Ω or less, and more preferably 100Ω or more and 1000Ω or less. The rated current of the suppression resistor 3 is not particularly limited, but may be, for example, 20 A, or 0.1 A to 100.0 A, preferably 1.0 A to 70.0 A, and more preferably 5.0 A to 40.0 A. The rated power of the suppression resistor 3 is not particularly limited, and may be, for example, 120 kW, or 1 kW or more and 5000 kW or less, preferably 10 kW or more and 1000 kW or less, and more preferably 50 kW or more and 500 kW or less.

[0024] <System-transformer circuit 4, etc.> As shown in Figs. 1 to 3, the system-transformer electric circuit 4 is an electric circuit between the system K and the transformer H as described above, and can also be said to be a main electric circuit. As described above, the system-to-circuit breaker electric circuit 4a is an electric circuit between the system K and the system-side circuit breaker 2a, the circuit breaker-to-circuit breaker electric circuit 4b is an electric circuit between the system-side circuit breaker 2a and the transformer-side circuit breaker 2b, the circuit breaker-to-transformer electric circuit 4c is an electric circuit between the transformer-side circuit breaker 2b and transformer H, and the resistance circuit 4d is an electric circuit between the circuit breaker-to-circuit branch point 5b and the circuit breaker-to-transformer branch point 5c, and it can be said that these electric circuits 4a to 4d are part of the system-to-transformer electric circuit 4 (included in the system-to-transformer electric circuit 4). Here, the "electrical circuit" in the present invention is something that allows electricity to flow, and includes conductors such as copper, aluminum, silver, gold, and nichrome, cables in which such conductors are covered with an insulator, and general electric wires. The current flowing through the system-transformer electric circuit 4 described above may be three-phase three-wire (3φ3W) AC of 60 Hz or 50 Hz, or it may be single-phase three-wire (1φ3W) or single-phase two-wire (1φ2W) AC.

[0025] <Control device 10> As shown in FIGS. 1 to 3, the control device 10 is a device that controls the closing and opening of the above-mentioned system-side circuit breaker 2a and transformer-side circuit breaker 2b. The control device 10 may output a signal (on signal) to the system side circuit breaker 2a and the transformer side circuit breaker 2b to turn them on and a signal (off signal) to turn them off, respectively, and may input an answerback signal from each of the system side circuit breaker 2a and the transformer side circuit breaker 2b. The specific configuration of the control device 10 is not particularly limited, and may be, for example, a digital multimeter (e.g., one having the functions of an overcurrent relay (OCR) or an undervoltage relay (UVR)) B7, and the control device 10 may also include, in addition to this digital multimeter B7, a power fuse B1 connected between the digital multimeter B7 and the system-to-circuit breaker circuit 4a or the circuit breaker circuit 4b, an instrument transformer B2, a circuit protector B3, a voltmeter B4, a voltmeter changeover switch B5, an instrument current transformer B6, and the like (see FIG. 2). Additionally, the control device 10 may be a smart logger, a sequencer that executes a predetermined program, a computer, or the like. In one suppression circuit system 1, the number of control devices 10 may be one or more. The control device 10 may also be provided inside the same specified panel housing B in which the suppression circuit system 1 is provided, or it may be provided inside a separate box outside the specified panel housing B. The power supply for the control device 10 may be input from a predetermined uninterruptible power supply device provided inside the same predetermined panel housing B in which the control device 10 is provided. The monitoring, setting changes, operation, etc. of the control device 10 may be performed manually by a user on-site by directly touching it, or may be performed remotely via a communication device such as the Internet or a telephone line.

[0026] The control device 10 may control the closing of the system side circuit breaker 2a and the transformer side circuit breaker 2b so that the order of closing the system side circuit breaker 2a and the transformer side circuit breaker 2b is such that the system side circuit breaker 2a is closed first and the transformer side circuit breaker 2b is closed later. In more detail, the control device 10 may output a closing signal to the system side circuit breaker 2a and then output a closing signal to the transformer side circuit breaker 2b. In this case, the time difference between closing the system side circuit breaker 2a and closing the transformer side circuit breaker 2b may be the value or range as described above, but this time difference between closing may also be set by the control device 10 to a value or range as described above. Furthermore, when closing the system side circuit breaker 2a and the transformer side circuit breaker 2b, if a predetermined time has elapsed since the system side circuit breaker 2a was closed but the transformer side circuit breaker 2b has not been closed, the control device 10 may control the shutoff of the system side circuit breaker 2a. In more detail, if a predetermined time has elapsed since the control device 10 outputted a closing signal to the system side circuit breaker 2a but an answerback signal (a signal indicating that the circuit breaker has been closed) has not been input from the transformer side circuit breaker 2b, the control device 10 may output a shutoff signal to the system side circuit breaker 2a. In this case, the specified time after the system side circuit breaker 2a is closed may be a value or range as described above, or this specified time may be set by the control device 10 to a value or range as described above.

[0027] <Other> The present invention is not limited to the above-described embodiment. The components of the suppression circuit system 1 and the like, or the overall structure, shape, dimensions, etc., can be appropriately changed in accordance with the spirit of the present invention. The suppression circuit system 1 does not necessarily have to include the control device 10 . The suppression circuit system 1 may be retrofitted to a predetermined plant such as an existing power receiving and distribution plant, or may be used in place of a high voltage AC load switch when a new predetermined plant is installed. The suppression circuit system 1 does not have any particular limitations on the order in which the system side circuit breaker 2a and the transformer side circuit breaker 2b are closed, and it is not necessary to shut off the system side circuit breaker 2a depending on the situation of the transformer side circuit breaker 2b being closed after the system side circuit breaker 2a is closed. Furthermore, in using the suppression circuit system 1, the order in which the system side circuit breaker 2a and the transformer side circuit breaker 2b are closed may be such that the system side circuit breaker 2a is closed first and the transformer side circuit breaker 2b is closed later, and in closing the system side circuit breaker 2a and the transformer side circuit breaker 2b, if the transformer side circuit breaker 2b has not been closed even after a predetermined time has elapsed since the system side circuit breaker 2a was closed, the system side circuit breaker 2a may be shut off. The system K and transformer H related to the suppression circuit system 1 described above, as well as the load F, the storage device T, the power generation device S, the specified panel housing B, and the specified plant P will be explained in detail below.

[0028] <System K> As shown in Figs. 1 to 3, system K transmits (receives) electricity to the suppression circuit system 1 and transformer H, and refers to the entire system through which electric power companies and the like supply electricity to consumers, and can also be called power system K. Specifically, system K includes facilities such as substations, transmission lines, and distribution lines, and may also include power plants. System K may also include a utility transformer, a power purchase watt-hour meter, a power sale watt-hour meter, a pole-mounted air switch, a protective relay device, and the like that are present outside a specific panel housing B in which the suppression circuit system 1 is installed. The power handled by such system K may be either AC or DC, but the following description will be given assuming that it is AC. In system K, most of the electricity transmitted is AC, so it is transmitted using three-phase, three-wire (3φ3W) transmission lines. In order to reduce transmission losses during transmission, the main long-distance transmission sections transmit electricity at as high a voltage as possible (for example, 6,600V or 22,000V). The electricity transmitted by system K is transformed (stepped down) in several stages at locations close to the consumption point, and after the pole-mounted transformer, the electricity is distributed via single-phase two-wire (1φ2W) or similar. System K may be a system of an electric power company or the like (commercial power system), or may be a system independently owned by an organization such as a company or a local government, or a system within a plant (independent power system).

[0029] <Transformer H> 1 to 3, the transformer H is a so-called transformer that transforms the AC current from the system K into an AC current with a voltage suitable for the above-mentioned load F. Incidentally, the term "transformer" is an abbreviation of "transformer." The specific configuration of transformer H is not particularly limited, but may be, for example, a two-winding transformer (see Figures 1 and 3), a three-winding transformer (see Figure 2), or a transformer with four or more windings. The transformer H is not particularly limited with respect to the connection method of each of its windings, and may be, for example, a star connection (Y connection) or a delta connection (Δ connection). In addition, the transformer H may be provided with a grounding terminal, a contact prevention plate, etc., and may be an oil-immersed transformer (self-cooled, air-cooled, water-cooled, etc.) or a dry-type transformer (self-cooled, air-cooled, water-cooled, etc.).

[0030] <Load F> As shown in Figures 2 and 3, the load F is a load (load equipment) that consumes power received from a system K via a transformer H, and consumes stored power from a power storage device T (described later) and generated power from a power generation device S. The load F may be, for example, an automobile dealership or a gas station, a rental car store (rental agency), a charger Fa (described below) in a factory or workshop, or may include electrical equipment and facilities that use electricity such as electric and electronic devices (general lighting loads Fb such as incandescent lamps, fluorescent lamps, and mercury lamps (lighting fixtures), and general power loads Fc such as air conditioners, motors, and pumps), or it may even include the factory or workshop itself. In addition, load F may include devices that use electricity, such as electrical and electronic equipment in corporations, organizations, individuals, government offices, and associations, homes, stores, warehouses, garages, car parks, bicycle parking lots, school buildings, auditoriums, gymnasiums, research facilities, hospitals, clinics, inns, hotels, theaters, movie theaters, stadiums, baseball stadiums, etc., or the company offices themselves, or it may include a combination of these. In the following, the charger Fa will be explained in detail in particular. The charger Fa may be any of a rapid charger, a normal charger, an ultra-rapid charger, etc. Here, the "charger Fa" in the present invention refers to a stationary charging device or charging facility used to charge vehicles with built-in batteries (storage batteries), such as electric vehicles (EVs), plug-in hybrid vehicles, and electric motorcycles, and is also called a charging stand, charging station, charging spot, etc. Note that the charger Fa may also be a charging device or charging facility used to charge communication devices such as smartphones and mobile phones with built-in batteries (storage batteries), portable PCs (personal computers), electrical appliances, etc., other than vehicles.

[0031] <Power storage device T> As shown in Figs. 2 and 3, the power storage device T is a device that stores power received from a system K via a transformer H, power generated by a power generation device S, which will be described later, and the like. The energy storage device T may be, for example, a storage battery such as a lead acid battery, a lithium ion battery, a nickel-metal hydride battery, or a nickel-cadmium battery; it may store hydrogen produced by electrolysis of water using the power generated by the power generation device S, and extract electricity when needed using a fuel cell or the like; or it may be a device that stores electricity as kinetic energy using a flywheel or the like, stores electricity as potential energy using pumped water, or stores electricity directly as electrical energy using a capacitor or the like.

[0032] <Generator S> As shown in Figures 2 and 3, the power generation device S may have any configuration as long as it generates electricity, and may be, for example, a device that generates electricity using solar power, wind power, hydroelectric power, geothermal power, solar thermal power, heat in the atmosphere or other heat present in nature, or biomass (organic matter derived from plants and animals that can be used as an energy source). In addition, the power generating device S may generate power by utilizing ocean temperature difference, wave power, tidal currents (ocean currents), or tides. The power generated by the power generation device S may be consumed by a load F, stored in a power storage device T, or sold to a power grid K via a transformer H.

[0033] <Specified panel case B> As shown in FIGS. 2 and 3, a predetermined panel housing B (hereinafter, also referred to as "panel housing B") is a housing that houses devices such as the suppression circuit system 1 and the control device 10 described above. As described above, inside panel housing B may be provided a power fuse (PF) B1, a voltage transformer (VT) B2, a circuit protector (CP) B3, a voltmeter B4, a voltage change over switch (VS) B5, a current transformer (CT) B6, and a digital multimeter (e.g., one having the functions of an over current relay (OCR) or an under voltage relay (UVR)) B7 (see FIG. 2). Furthermore, inside the panel casing B, circuit breakers (which can be called circuit breakers downstream of the transformer, particularly a molded case circuit breaker or a ground fault circuit breaker) B8 may be provided between the transformer H and each load F (Fa, Fb, Fc), the storage device T, and the power generation device S. In more detail, a charging load circuit breaker B8Fa connected to the electric path between the transformer H and the charger Fa and capable of interrupting the electric path, a lighting load circuit breaker B8Fb connected to the electric path between the transformer H and the lighting load Fb and capable of interrupting the electric path, a power load circuit breaker B8Fc connected to the electric path between the transformer H and the power load Fc and capable of interrupting the electric path, a storage circuit breaker B8T connected to the electric path between the transformer H and the storage device T and capable of interrupting the electric path, and a generation circuit breaker B8S connected to the electric path between the transformer H and the power generation device S and capable of interrupting the electric path may be provided (see Figures 2 and 3). In addition, a disconnect switch (DS), a high-voltage AC load break switch with current-limiting fuse (LBS), a zero-phase potential device (ZPD), a synchronism detector, a voltage detector, an autotransformer, an uninterruptible power supply (UPS), fuses (F), an ammeter, an ammeter change over switch (AS), and a power meter may be provided inside panel case B.

[0034] <Prescribed plant P> As shown in Figures 1 to 3, a specific plant P (hereinafter also referred to as "plant P") is, for example, a plant such as a power distribution plant, and has the above-mentioned suppression circuit system 1 and a transformer H, and may also have a load F, a storage device T, a power generation device S, and a specific panel housing B. The plant P may be a power receiving and distribution plant, a plant that only distributes power, or a plant that only receives power, and depending on its application, there are no particular limitations on which of the load F, storage device T, power generation device S, and panel housing B the plant P has. In one plant P, the number of transformers H and panel cases B may be one (see Figure 2) or multiple (see Figure 3), but the number of transformers H and panel cases B may be the same. In particular, FIG. 3 shows a case where there are a plurality of transformers H and panel housings B in one plant P. In this case, the suppression circuit system 1 may be provided only in the panel housing B that is directly connected to the system K among the plurality of panel housings B. The panel housing B that is directly connected to the system K may be said to be, so to speak, a parent panel housing B', and the panel housings B other than this parent panel housing B' may be said to be child panel housings B". The same is true for the transformer H, and the transformer H provided in the parent panel housing B' may be said to be a parent transformer H'. That is, the transformer H provided in the slave panel case B" can be said to be a slave transformer H", the circuit breaker-transformer electric circuit 4c provided inside the master panel case B' can be said to be a parent circuit breaker-transformer electric circuit 4c', and the electric circuit branching off from this parent circuit breaker-transformer electric circuit 4c' to the slave transformer H" can be said to be a slave circuit breaker-transformer electric circuit (or connecting electric circuit) 4c". Incidentally, this slave circuit breaker-transformer electric circuit 4c" can also be said to be part of the system-transformer electric circuit 4 (included in the system-transformer electric circuit 4). A sub-circuit breaker B9 that is connected to this sub-circuit-to-transformer electric circuit 4c'' and is capable of breaking the electric circuit may be provided inside the sub-board housing B''. [Industrial Applicability]

[0035] The suppression circuit system of the present invention can be used not only in cases where there is a high-voltage contract (high-voltage incoming, high-voltage incoming) for power of 50 kW or more from the grid, but also in cases where there is a low-voltage contract (low-voltage incoming, low-voltage incoming) for power of less than 50 kW, or in cases where there is an extra-high voltage (extra-high) contract (extra-high voltage incoming, extra-high voltage incoming) for power of 20,000 kW or more, and with any power contract or incoming type, and can be used both indoors and outdoors. [Explanation of symbols]

[0036] 1. Suppression circuit system 2 Circuit Breaker 2a System side circuit breaker 2b Transformer side circuit breaker 3 Suppression resistance K lineage H Transformer

Claims

1. A suppression circuit system having a circuit breaker (2) and a suppression resistor (3) connected to an electric path between a system (K) and a transformer (H), The circuit breaker (2) includes a system side circuit breaker (2a) and a transformer side circuit breaker (2b), The system-side circuit breaker (2a) and the transformer-side circuit breaker (2b) are connected in series in an electric path between the system (K) and the transformer (H), The suppression circuit system is characterized in that the suppression resistor (3) is connected in parallel with the transformer-side circuit breaker (2b) across an electric path between the system-side circuit breaker (2a) and the transformer-side circuit breaker (2b) and an electric path between the transformer-side circuit breaker (2b) and a transformer (H).

2. 2. The suppression circuit system according to claim 1, wherein the order of closing the system side circuit breaker (2a) and the transformer side circuit breaker (2b) is such that the system side circuit breaker (2a) is closed first and the transformer side circuit breaker (2b) is closed second.

3. 3. The suppression circuit system according to claim 2, wherein, when the system-side circuit breaker (2a) and the transformer-side circuit breaker (2b) are closed, if the transformer-side circuit breaker (2b) is not closed even after a predetermined time has elapsed since the system-side circuit breaker (2a) was closed, the system-side circuit breaker (2a) is shut off.

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