KR20190115600A - Power compensator - Google Patents

Abstract

The present invention relates to a power compensator which comprises first and second input busbars, a sub module, a bypass switch, an interface, and a power supply. The sub module can include a plurality of switching modules connected to the first and second input busbars and a first capacitor element connected to the switching module so as to charge a first power source. The bypass switch can be connected between the first input busbar and the second busbar. The interface can control the bypass switch. The power supply can generate a second power source and a third power source for driving the bypass switch by using the first power source. The second power source can be supplied to the bypass switch under control of the interface when the sub module fails and the third power source can be supplied to the bypass switch when the sub module and the interface fail.

Description

Power compensator

An embodiment relates to a power compensation device.

As industry develops and population grows, soaring demand for electricity has limits.

Accordingly, the power system for supplying the power generated in the production site stably without loss is becoming increasingly important.

There is a need for a flexible AC transmission system (FACTS) facility to improve power flow, grid voltage, and stability. The STATCOM (STATCOM) equipment, a kind of power compensation device called the third generation of FACTS facilities, is fed in parallel to the power system to compensate for reactive and active power required by the power system.

1 shows a general power system system.

As shown in FIG. 1, the general power system 10 may include a power generation source 20, a power system 30, a load 40, and a plurality of power compensators 50.

The power generation source 20 refers to a place or a facility for generating power, and can be understood as a producer for generating power.

The power system 30 may refer to any facility including a power line, a pylon, an arrester, an insulator, etc. for transmitting power generated from the power generation source 20 to the load 40.

The load 40 refers to a place or a facility that consumes power generated by the power generation source 20, and may be understood as a consumer consuming power.

The power compensation device 50 may be a device that is connected to the power system 30 and compensates for the corresponding active power or reactive power according to the supply or shortage of the active power or the reactive power among the power flowing to the power system 30. .

The power compensator 50 is a recent trend of increasing STATCOM facilities of the multilevel converter (MMC) type. The multilevel converter type STATCOM consists of a number of submodules, and these submodules consist of various internal devices.

A bypass switch is provided between the first and second input bus bars of each submodule to prevent failure of the plurality of submodules. If the submodule fails, the bypass switch is turned on and the submodule is dropped.

This bypass switch is controlled by an interface that manages the submodule.

However, when the interface is broken, there is a problem that the bypass module is not driven and the submodule is not dropped.

The embodiment aims to solve the above and other problems.

Another object of the embodiment is to provide a power compensation device with enhanced reliability for submodule dropout.

According to an aspect of the embodiment to achieve the or another object, the power compensation device, the first and second input bus bar, a plurality of switching modules connected to the first and second input bus bar and the switching module is connected. A sub module including a first capacitor device configured to be charged with a first power source; A bypass switch connected between the first input bus bar and the second input bus bar; An interface for controlling the bypass switch; And a power supply configured to generate a second power source and a third power source for driving the bypass switch using the first power source. The second power may be supplied to the bypass switch under the control of the interface when the submodule fails, and the third power may be supplied to the bypass switch when the submodule and the interface fail.

According to another aspect of the embodiment, the power compensation device, the first and second input bus bar; A plurality of switching modules connected to the first and second input bus bars; A capacitor device connected to the switching module to charge a first power source; A bypass switch connected between the first input bus bar and the second input bus bar; An interface for controlling the bypass switch; And a power supply configured to generate a second power source and a third power source for driving the bypass switch using the first power source. The second power may be supplied to the bypass switch under the control of the interface when the submodule fails, and the third power may be supplied to the bypass switch when the submodule and the interface fail.

Referring to the effect of the power compensation device according to the embodiment as follows.

According to at least one of the embodiments, even if the interface fails or the control of the bypass switch is impossible, when the submodule fails, the bypass switch may be turned on by the power supplied from the power supply, thereby causing the submodule to be dropped. It has the advantage that it can strengthen the reliability of module dropout.

Further scope of the applicability of the embodiments will become apparent from the detailed description below. However, various changes and modifications within the spirit and scope of the embodiments can be clearly understood by those skilled in the art, and therefore, specific embodiments, such as the detailed description and the preferred embodiments, are to be understood as given by way of example only.

1 shows a general power system system.
2 illustrates an MMC-based power compensation device according to an embodiment.
3 is a circuit diagram of an MMC-based power compensation apparatus according to an embodiment.
4 is a perspective view illustrating a submodule according to an embodiment.
5 is a circuit diagram of a submodule according to an embodiment.
6 is a block diagram illustrating a power compensation device according to an embodiment.
7 is a circuit diagram illustrating a power compensation device according to an embodiment.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments disclosed herein will be described in detail with reference to the accompanying drawings, and the same or similar components will be given the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other. In addition, in describing the embodiments disclosed herein, when it is determined that the detailed description of the related known technology may obscure the gist of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, the accompanying drawings are intended to facilitate understanding of the embodiments disclosed herein, but are not limited to the technical spirit disclosed herein by the accompanying drawings, all changes included in the spirit and scope of the embodiments, It should be understood to include equivalents and substitutes.

2 illustrates an MMC-based power compensation device according to an embodiment.

Referring to FIG. 2, the power compensator according to the embodiment may include a plurality of insulation units 81, 83, 85, and a plurality of cabinets 91, 93, 95 provided on the frame 70 and stacked on each other. have.

The insulating units 81, 83, 85 located between the cabinets 91, 93, 95 are each sub-module units 11-1, 11-3, 11-5 housed in the cabinets 91, 93, 95. ) Can be insulated

The first submodule unit 11-1 accommodated in the first cabinet 91 may include a plurality of submodules 92 for converting a voltage of a first phase, for example, a phase among three phase AC voltages. The second sub module unit 11-3 accommodated in the second cabinet 93 may include a plurality of sub modules 94 for converting a second phase, for example, a b phase voltage among three phase AC voltages. The third sub module unit 11-5 accommodated in the third cabinet 95 may include a plurality of sub modules 96 for converting a voltage of a third phase, for example, a c phase among three phase AC voltages.

An input busbar 71 is connected to the first submodule among the plurality of submodules 92, an output busbar 75 is connected to the last submodule, and a connection busbar 73 is connected between the other submodules. Can be connected.

Each submodule 92, 94, 96 may be drawn into the cabinets 91, 93, 95 by a guide sliding rail 68 provided above the cabinets 91, 93, 95.

In FIG. 2, three cabinets 91, 93, and 95 and three insulation units 81, 83, and 85 are illustrated for convenience of description, but the number of cabinets 91, 93, and 95 may be changed according to user needs. The number of the insulating units 81, 83, 85 can be variously modified, which does not limit the scope of the invention.

A wheel 103 for moving the frame 70 may be installed below the frame 70, but is not limited thereto.

By the wheels 103, the frame 70 having a heavy load can be easily moved to a desired place.

If the frame 70 is fixed in a specific place, the wheel 103 can be omitted.

The power compensator of the embodiment includes a plurality of branch pipes 110 and branch pipes branched from the main pipe 120 and the main pipe 120 to the cabinets 91, 93, and 95 installed on one side of the frame 70. 110 may include a plurality of sub branch pipes 76 branched from each other and connected to each sub module 92, 94, 96.

The main tube 120 may include a first main tube 121 for receiving the coolant and a second main tube 123 for extracting the coolant. The branch pipe 110 is connected to the first main pipe 121 to connect the first branch pipe 111 and the second main pipe 123 to receive the coolant and the second branch pipe 113 to discharge the coolant. It may include. The sub branch pipe 76 connects the first branch pipe 111 and the inlet side of the submodules 92, 94, and 96 so as to obtain the coolant into the inlet side of the submodules 92, 94, and 96. A second sub branch pipe that connects the engine 77, the second branch pipe 113, and the water outlet side of the submodules 92, 94, and 96 to discharge coolant from the water outlet side of the submodules 92, 94, and 96. And (79).

3 is a circuit diagram of an MMC-based power compensation apparatus according to an embodiment.

 As shown in FIG. 3, the MMC-based power compensator 10 may include a plurality of submodules 92, 94, and 96 connected in series for each phase. By the operation of the plurality of submodules 92, 94, and 96, active power or reactive power may be supplied to the power system, or active power or reactive power may be absorbed from the power system.

Although the Y-type power compensation device is shown in FIG. 3, the Δ-type power compensation device may also be adopted in the present invention.

A plurality of submodules 92, 94, and 96 provided in each phase may be defined as one valve, but is not limited thereto.

4 is a perspective view illustrating a submodule according to an embodiment, and FIG. 5 is a circuit diagram of a submodule according to an embodiment.

4 and 5, the submodules 92, 94, and 96 according to the embodiment may include a power pack 13 and a capacitor pack 55.

The power pack 13 and the capacitor pack 55 may be electrically connected. The capacitor pack 55 may be charged and discharged by the switching operation of the power pack 13.

The capacitor pack 55 may include a case and a capacitor element 56 installed in the case.

The capacitor pack 55 may be electrically connected to the rear surface of the power pack 13.

The housing of the power pack 13 may include, for example, a switching module 15, a resistor 49, a self power supply 51 (SPS), and a sub module interface (SMI) 53.

The switching module 15 may include first to fourth switching modules 17, 19, 21, and 23.

Each switching module 17, 19, 21, 23 may include switching elements 25, 27, 29, 31, diodes 33, 35, 37, 39, and gate drivers 41, 43, 45, 47. Can be. The diodes 33, 35, 37, 39 may be free-wheeling diodes connected in anti-parallel to the switching elements 25, 27, 29, 31.

That is, the first switching module 17 may include the first switching device 25, the first diode 33, and the first gate driver 41. The second switching module 19 may include a second switching device 27, a second diode 35, and a second gate driver 43. The third switching module 21 may include a third switching device 29, a third diode 37, and a third gate driver 45. The fourth switching module 23 may include a fourth switching element 31, a fourth diode 39, and a fourth gate driver 47.

Each of the first to fourth switching devices 25, 27, 29, and 31 may be switched by a gate signal provided from the interface 53. For example, each of the first to fourth switching elements 25, 27, 29, and 31 may be turned off in response to a low level gate signal and turned on in response to a high level gate signal.

Each of the first to fourth switching devices 25, 27, 29, and 31 may include an Insulated Gate Bipolar Transistor (IGBT) device, but is not limited thereto.

That is, the first switching element 25 is a first IGBT element, the second switching element 27 is a second IGBT, the third switching element 29 is a third IGBT, and the fourth switching element 31 is It may be a fourth IGBT.

In this case, the first IGBT may include a gate terminal connected to the output terminal of the first gate driver 41, a collector terminal connected to the first node 22, and an emitter terminal connected to the second node 24. have. The first diode 33 may be connected between the collector terminal and the emitter terminal of the first IGBT in reverse parallel with the first IGBT.

The second IGBT may include a gate terminal connected to the output terminal of the second gate driver 43, a collector terminal connected to the first node 22, and an emitter terminal connected to the third node 26. The second diode 35 may be connected between the collector terminal and the emitter terminal of the second IGBT in reverse parallel with the second IGBT.

The third IGBT may include a gate terminal connected to the output terminal of the third gate driver 45, a collector terminal connected to the second node 24, and an emitter terminal connected to the fourth node 28. The third diode 37 may be connected between the collector terminal and the emitter terminal of the third IGBT in reverse parallel with the third IGBT.

The fourth IGBT may include a gate terminal connected to the output terminal of the fourth gate driver 47, a collector terminal connected to the third node 26, and an emitter terminal connected to the fourth node 28. The fourth diode 39 may be connected between the collector terminal and the emitter terminal of the fourth IGBT in reverse parallel with the fourth IGBT.

In such a connection structure, when the first IGBT is turned on, both the forward current and the reverse current may flow through the IGBT. When the first IGBT is turned off, the forward current flows through the first diode 33 but the reverse current cannot flow through the first diode 33.

Herein, the current in the forward direction may draw current into the first output terminal 57 and draw current into the second output terminal 59. In the reverse current, a current may be drawn into the second output terminal 59 and a current may be drawn into the first output terminal 57.

Other IGBTs may also flow or be blocked as forward or reverse currents as they are turned on or turned off, but a detailed description thereof may be readily understood from the description of the turn on / turn off of the first IGBT above for further details. Is omitted.

In the present invention, by the operation of the first to fourth switching module (15, 17, 19, 21, 23) of each of the plurality of sub-module (9) configured in this way, the AC power to DC power and the DC power to AC power Can be converted.

For example, the AC power input to the first and second output terminals 57 and 59 may not affect the operation of the first to fourth switching modules 15, 17, 19, 21, and 23 of each of the plurality of submodules 9. It can be converted into direct current power to be charged in the capacitor element 56. In addition, the DC power charged in the capacitor element 56 is converted into AC power by the operation of the first to fourth switching modules 15, 17, 19, 21, 23 of each of the plurality of submodules 9 to be electric power. Can be supplied to the system.

The capacitor element 56 may be installed in the housing of the capacitor pack 55. In detail, one side of the capacitor element 56 is connected to the first conductor 60 (or the first node 22), and the other side of the capacitor element 56 is the second conductor 62 (or the fourth node). 28)). The capacitor element 56 is introduced into the first and second output terminals 57 and 59 and converted into power by the first to fourth switching modules 15, 17, 19, 21, and 23 of the submodule 9. Can be charged.

The resistance element 49 may be installed in the housing of the power pack 13 and may be connected in parallel with the capacitor element 56. That is, the resistance element 49 may also be connected to one side of the first conductor 60 (or the first node 22) and the other side thereof to the second conductor 62 (or the fourth node 28). have.

When voltage is applied to the first and second output terminals 57 and 59 in a state where no capacitor voltage is initially charged in the capacitor device 56, overcurrent and / or overvoltage are generated. The resistance element 49 may stabilize the overcurrent and / or overvoltage so that the capacitor element 56 may be stably charged with voltage. In addition, the resistance element 49 may have a discharge function to discharge the voltage charged in the capacitor element 56 while the submodule 9 is in operation or stopped.

The self-power supply 51 can drive the interface 53 or each switching module 15, 17, 19, 21, 23 using this voltage as a source when a certain voltage is charged in the capacitor element 56. . For example, when the capacitor device 56 is charged with a voltage of at least 1400 V or more, the self-power supply 51 generates a supply voltage of 24 V to the interface 53 or each switching module 15, 17, 19, 21, 23. The interface 53 or each switching module 15, 17, 19, 21, 23 can be driven by this power supply.

The interface 53 may manage and / or control all devices installed in the submodule 9 as a whole.

For example, when the interface 53 is driven by the supply power supplied from the self-power supply 51, a gate signal for controlling each switching control module may be generated based on a command value provided from the upper controller. In response to the gate signal, each switching element 25, 27, 29, 31 included in each switching module 15, 17, 19, 21, 23 may be turned on / off.

The interface 53 communicates with each switching module 15, 17, 19, 21, 23, the capacitor element 56, the resistor element 49, and the self-power supply 51 to communicate with each switching and capacitor element 56. The state information of each of the resistance element 49 and the self power supply 51 may be provided.

The interface 53 determines the failure of the submodule 9 and the like based on such various states, and controls the bypass switch (BPS) Bypass Switch (BPS) if it is determined that the submodule 9 has failed. Thus, the bypass switch 61 may be turned on so that the corresponding submodule 9 may not be used.

The interface 53 may adjust the gate signal to be supplied to each of the switching modules 15, 17, 19, 21, and 23 based on the state information and the command value provided from the host controller, but is not limited thereto.

As described above, each submodule 9 may be provided with a plurality of components or devices.

In particular, each submodule 9 may be provided with a capacitor element 56 included in the capacitor pack 55 and a resistor element 49 included in the power pack 13.

The first and second input bus bars 57 and 59 may be installed to protrude outwardly, that is, forward of the power pack 13. The first and second input bus bars 57 and 59 may be connected to the plurality of switching modules 17, 19, 21, and 23 installed in the case 141 through the case 141.

The first and second input bus bars 57 and 59 may be electrically connected by a bypass switch 61. That is, the first switch terminal 161 of the bypass switch 61 is connected to the first input booth portion 57, and the second switch terminal 163 of the bypass switch 61 is connected to the second input booth bar ( 59).

The bypass switch 61 is provided between the first and second input bus bars 57 and 59 when an error occurs in an apparatus including the switching modules 17, 19, 21, and 23 in the power pack 13. Is electrically conducted to bypass the current from the first input bus bar 57 to the second input bus bar 59 via the bypass pass switch 61, thereby dropping the sub-module including the power pack 13. You can. Here, the dropout may mean that the corresponding submodule is not used.

The rear surface of the power pack 13 and the capacitor pack 55 may be fastened by the first and second connection bus bars 63 and 65. The power pack 13 and the capacitor pack 55 may be electrically connected. The first and second connection bus bars 63 and 65 may protrude to the outside of the power pack 13, for example, to the rear.

The upper side of the power pack 13 corresponds to the sliding rail portion 68 installed above the cabinets 91, 93, and 95 so that the power pack 13 can slide when the power pack 13 is drawn into the cabinets 91, 93, and 95. The first sliding guide portion 1191 may be provided.

Similarly, the upper side of the capacitor pack 55 corresponds to the sliding rail portion 68 provided above the cabinets 91, 93, 95, so that when the capacitor pack 55 is drawn into the cabinets 91, 93, 95. A second sliding guide portion 1193 may be provided to allow sliding.

The first and second sliding guide parts 1191 and 1193 may be collectively referred to as the sliding guide part 119.

Reference numerals 151 and 153 may be connector terminals provided in the capacitor pack 55 to be connected to the connection bus bars 63 and 65 provided in the power pack 13.

6 is a block diagram illustrating a power compensation device according to an embodiment.

Referring to FIG. 6, the power compensator according to the embodiment may include a submodule 92, a power supply 51, an interface 53, a gate driver 41, and a bypass switch 61.

Alternatively, the power supply 51, the interface 53, the gate driver 41, and the bypass switch 61 may also be included in the submodule 92.

The submodule 92 illustrated in FIG. 6 may be one submodule among the plurality of submodules 92, 94, and 96 illustrated in FIGS. 2 and 3.

The gate driver 41 shown in FIG. 6 may be a gate driver of one of the plurality of gate drivers 41, 43, 45, and 47 shown in FIG. 5.

As shown in FIG. 5, the submodule 92 includes first and second input bus bars 57 and 59, first to fourth switching modules 17, 19, 21, and 23, and a capacitor element 56. It may include.

The first to fourth switching modules 17, 19, 21, and 23 are connected to the first and second input bus bars 57 and 59 to form the first to fourth switching modules 17, 19, 21, and 23. By the switching operation, AC power can be converted into DC power or DC power can be converted into AC power.

The capacitor element 56 stores energy (power) input to the sub module 92, and this energy may be used as a power source for driving various devices installed in the sub module 92 and reactive power in the power system. It may be supplied as Here, the various devices include, for example, an interface 53, a gate driver 41, a bypass switch 61, and the like.

The bypass switch 61 may be connected between the first input bus bar 57 and the second input bus bar 59. The bypass switch 61 may be turned on under the control of the interface 53. That is, when the submodule 92 fails, the interface 53 generates a control signal, and the bypass switch 61 may be turned on by the control signal. When the bypass switch 61 is turned on, a bypass passage is formed through the first input bus bar 57, the bypass switch 61, and the second input bus bar 59, so that AC power or DC power is generated. The first to fourth switching modules 17, 19, 21, and 23 of the submodule 92 may not be supplied.

On the other hand, the power charged in the capacitor element 56 is not used as the power of each of the interface 53, the gate driver 41 and the bypass switch 61 as it is. That is, power sources for driving the interface 53, the gate driver 41, and the bypass switch 61 are different from each other. Accordingly, the power supply of the capacitor element 56 may be converted into the power supply of each of the interface 53, the gate driver 41, and the bypass switch 61. The power supply 51 may be provided to convert the power.

The power supply 51 may provide a transformer 207. The transformer 207 may convert the power of the capacitor element 56 into the power of each of the interface 53, the gate driver 41, and the bypass switch 61.

The interface 53, the gate driver 41, and the bypass switch 61 may be driven by various power sources converted by the power supply 51.

The gate driver 41 may generate the gate signal based on the power input from the power supply 51 to switch the first to fourth switching modules 17, 19, 21, and 23.

The interface 53 may control the gate driver 41 and / or the bypass switch 61 based on the power input from the power supply 51.

The interface 53 may receive a call signal from an upper stage, for example, a controller, and provide a control signal to the gate driver 41 in response to the call signal. The gate driver 41 may generate a gate signal in response to the control signal.

The interface 53 may generate a control signal for conducting the bypass switch 61 when the submodule 92 fails. Power may be supplied to the bypass switch 61 in response to the control signal so that the bypass switch 61 may be turned on by the power.

For example, a sensor (not shown) may be provided to detect whether the first to fourth switching modules 17, 19, 21, and 23 fail. The interface 53 determines whether the first to fourth switching modules 17, 19, 21, 23 have failed based on the detection signals provided from the sensor, and the first to fourth switching modules 17, 19, 21, 23) can generate a control signal when the failure. Power input from the power supply 51 may be charged to the interface 53. In this case, the charged power may be supplied to the bypass switch 61 by the control signal. To this end, a switch (not shown) which may be turned on by a control signal may be provided at an output terminal of the charged power.

On the other hand, when the interface 53 is broken, even if the sub-module 92 is broken, the bypass switch 61 may not be turned on so that the sub-module 92 may not be dropped.

According to the embodiment, even if the interface 53 fails or the bypass switch 61 cannot be controlled, when the sub module 92 fails, the bypass switch 61 is turned off by the power supplied from the power supply 51. The sub-module 92 may be pulled out so that the reliability of the drop-out of the sub-module 92 can be enhanced.

7 is a circuit diagram illustrating a power compensation device according to an embodiment.

As shown in FIG. 7, the power supply 51 may include a converter 201 and a transformer 207.

The converter 201 may be a dual switch fly-back converter (DSFC). The input terminal of the converter 201 may be connected to the capacitor element 56 of the sub module 92. Therefore, the charged power to the capacitor element 56 may be input to the input terminal of the converter 201.

The converter 201 may include first and second switching modules 203 and 205. The power charged in the capacitor device 56 may be converted into the first power by switching of the first and second switching modules 203 and 205.

In FIG. 7, only the converter 201 for driving the interface 53 and the bypass switch 61 is illustrated, but a plurality of converters for driving the gate driver 41 or other electronic devices may be separately provided. .

The transformer 207 may include a first transformer T1 provided on the primary side and second and third transformers T2 and T3 provided on the secondary side. The transformer 207 may be connected to the output terminal of the converter 201.

The first power output from the converter 201 may be converted into the second power by the first transformer T1 and the second transformer T2 corresponding thereto. In addition, the first power output from the converter 201 may be converted into a third power by the first transformer T1 and the third transformer T3 corresponding thereto.

As will be described later, the second power source or the third power source may be used as a power source for driving the bypass switch 61. The voltage of the second power source and the voltage of the third power source may be the same, but the present invention is not limited thereto.

The interface 53 may be connected to the transformer 207. The interface 53 may control the submodule 92 as a whole. For example, the interface 53 may control the conduction of the bypass switch 61.

To this end, the interface 53 may include a capacitor device 54 and a first diode 52.

The capacitor element 56 connected to the first to fourth switching modules 17, 19, 21, and 23 is referred to as a first capacitor element, and the capacitor element 54 provided in the interface 53 is a second capacitor element. It may be referred to as.

The first diode 52 is a break of diode (BOD), and a conduction voltage for conduction may be set. Accordingly, the first diode 52 may not conduct below the conduction voltage, but may conduct at the conduction voltage or greater than that.

The first diode 52 may be connected in series with the capacitor element 54. For example, one side of the capacitor element 54 may be connected to one side of the second transformer T2 of the transformer unit 207.

For example, one side of the first diode 52 may be connected to the other side of the capacitor device 54 and the other side of the first diode 52 may be connected to the bypass switch 61.

Although not shown in FIG. 7, the first diode 52 is connected between the second transformer T2 of the transformer unit 207 and the capacitor element 54, and the capacitor element 54 is connected to the first diode 52. It may be connected between the bypass switch 61.

The second power source converted by the second transformer T2 of the transformer unit 207 may be charged in the capacitor element 54 of the interface 53. The second power charged in the capacitor element 54 may be supplied to the bypass switch 61 under the control of the first diode 52. That is, when the first diode 52 is turned on, the second power charged in the capacitor element 54 is supplied to the bypass switch 61, and the bypass switch 61 is turned on by the second power supply. Module 92 may be dropped.

The conduction voltage of the first diode 52 may be set to the second power source when the submodule 92 fails. When the submodule 92 is normally driven, that is, when the first to fourth switching modules 17, 19, 21, and 23 are normally switched by the gate signal of the gate driver 41, the capacitor element 56 is turned on. Since the voltage is continuously charged and discharged, the residual voltage of the capacitor device 56 may be less than or equal to the rated voltage of the capacitor device 56. However, when the sub-module 92 fails, for example, when the first to fourth switching modules 17, 19, 21, and 23 do not open after being turned on, the first and second input bus bars 57 and 59 Power is charged by the rated voltage of the capacitor element 56 via the first to fourth switching modules 17, 19, 21, and 23, and power not charged in the capacitor element 56 is transferred to the power supply 51. Supplied. Therefore, since a voltage larger than the rated voltage of the capacitor element 56 is supplied to the power supply 51, the second power source and the third power source generated by the transformer unit 207 of the power supply 51 can be increased. . In other words, the second power source and the third power source when the submodule 92 is broken may be greater than the second power source and the third power source when the submodule 92 is broken.

At this time, since the first diode 52 is set as the second power source when the submodule 92 is broken, the first diode 52 is damaged due to the failure of the submodule 92 and the second transformer ( Since the second power is increased by T2), the increased second power is supplied to the bypass switch 61 so that the bypass switch 61 can be turned on.

On the other hand, the interface 53 may be broken and the bypass switch 61 may not be controlled. That is, when an abnormality occurs in the power supply circuit of the interface 53, even if the submodule 92 fails, a voltage lower than the voltage of the second power supply when the submodule 92 fails is applied to the capacitor element 56. Can be charged. Alternatively, an error may occur in the control circuit of the interface 53 so that a control signal for driving the bypass switch 61 may not be generated. In this case, since the second power is not supplied from the interface 53 to the bypass switch 61, the bypass switch 61 may not be turned on so that the submodule 92 may not be dropped.

In order to solve this problem, the power supply 51 of the embodiment may include second and third diodes 215 and 213 connected in anti-parallel to each other.

For example, the second diode 215 and the third diode 213 connected in parallel with each other in consideration of the AC voltage of the third power supply by the third transformer T3 of the transformer 207. For example, the positive voltage of the third power supply may be supplied to the bypass switch 61 via the second diode 215. for example. The negative voltage of the third power supply may be supplied to the bypass switch 61 via the third diode 213.

If the second power source has a DC voltage, only one diode of the second and third diodes 215 and 213 may be provided.

The second and third diodes 215 and 213 are BODs, and a conduction voltage for conduction may be set. Accordingly, the second and third diodes 215 and 213 may not be conducted at or below the corresponding conduction voltage, and may be conducted at a corresponding conduction voltage or greater than that.

The conduction voltage of each of the second and third diodes 215 and 213 may be the same. The conduction voltage of each of the second and third diodes 215 and 213 may be greater than that of the first diode 52.

One side of the third transformer T3 of the transformer unit 207 is connected to one side of the second diode 215 or the third diode 213, and the other side of the third transformer T3 of the transformer unit 207 is It may be connected to one side of the pass switch 61. The other side of the second diode 215 or the third diode 213 may be connected to the other side of the bypass switch 61.

Therefore, when the second diode 215 or the third diode 213 is conducted, the third power source of the third transformer T3 of the transformer 207 is the second diode 215 or the third diode 213. The bypass switch 61 may be supplied to the bypass switch 61 via the third power supply so that the bypass switch 61 may be turned on by the third power source.

The conduction voltage of the first diode 52 is set to the second power source when the submodule 92 fails, and the second diode 215 or the third diode 213 is less than the conduction voltage of the first diode 52. It can be set to a large conduction voltage. Therefore, even when the first diode 52 is turned on by the second power supply by the second transformer T2 of the transformer unit 207 when the submodule 92 fails, the conduction voltage of the first diode 52 is lower than that of the first diode 52. The second diode 215 or the third diode 213 having a large conduction voltage is not conducted by the third power supply by the third transformer T3 of the transformer 207.

When the interface 53 is also broken in a situation where the submodule 92 is broken, the second power cannot be supplied from the interface 53 to the bypass switch 61. When the submodule 92 fails As described above, the electric power that is not charged to the capacitor element 56 of the submodule 92 is supplied to the power supply 51, and the third transformer of the transformer unit 207 ( The third power source generated by T3) can be increased. When the increased voltage of the third power source is increased by the conduction voltage of the second or third diodes 215 and 213, the second or third diodes 215 and 213 are turned on so that the third power source is bypass switch. The sub-module 92 may be dropped by being supplied to the 61 and the bypass switch 61 is turned on by the third power source.

The power supply 51 of the embodiment may further include a resistor 217.

The resistor 217 may be connected between the second or third diodes 215 and 213 and the bypass switch 61. When the second or third diodes 215 and 213 are conducted, an inrush current may be generated by the high voltage of the third power supply. The resistance element 217 may mitigate such inrush current so that the third power source can be stably supplied to the bypass switch 61.

The foregoing detailed description should not be construed as limiting in all respects, but should be considered as illustrative. The scope of the embodiments should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the embodiments are included in the scope of the embodiments.

13: power pack
41, 43, 45, 47: gate driver
51: power supply
52, 213, 215: Diode
53: interface
54, 56: capacitor element
55: capacitor pack
57, 59: input booth
61: bypass switch
63, 65: connecting booth
92, 94, 96: submodule
130: control board
136, 137: output electrode
161, 163: switch terminal
201: converter
203, 205: switching module
207: transformer
211: drive unit
217: current limiting unit
T1, T2, T3: Transformer

Claims (12)

A sub module including first and second input bus bars, a plurality of switching modules connected to the first and second input bus bars, and a first capacitor device connected to the switching modules to charge a first power source;
A bypass switch connected between the first input bus bar and the second input bus bar;
An interface for controlling the bypass switch; And
A power supply configured to generate a second power source and a third power source for driving the bypass switch using the first power source,
The second power is supplied to the bypass switch under control of the interface when the submodule fails.
And the third power source is supplied to the bypass switch when the submodule and the interface fail. The method of claim 1,
The interface is,
A second capacitor device in which the second power source is charged; And
And a first diode that controls the supply of the second power to the bypass switch. The method of claim 2,
The power supply,
And a second and a third diode for controlling the supply of the third power to the bypass switch. The method of claim 3,
And the second and third diodes are connected in reverse parallel with each other. The method of claim 3,
And a conduction voltage of the second diode equal to the conduction voltage of the third diode. The method of claim 5,
The conduction voltage of the first diode is set to the second power supply when the submodule fails. The method of claim 6,
And a conduction voltage of each of the second and third diodes is greater than the conduction voltage of the first diode. The method of claim 7, wherein
And the second power supply when the submodule fails, is larger than the second power source when the submodule is normal. According to claim 8,
And the sub-module fails, wherein the first diode is turned on so that the second power is supplied to the bypass switch. The method of claim 9,
And the second or third diode is conductive so that the third power is supplied to the bypass switch when the submodule and the interface have failed. The method of claim 3,
The power supply,
And a resistance element connected between the second or third diode and the bypass switch. First and second input bus bars;
A plurality of switching modules connected to the first and second input bus bars;
A capacitor device connected to the switching module to charge a first power source;
A bypass switch connected between the first input bus bar and the second input bus bar;
An interface for controlling the bypass switch; And
A power supply configured to generate a second power source and a third power source for driving the bypass switch using the first power source,
The second power is supplied to the bypass switch under control of the interface when the submodule fails.
And the third power source is supplied to the bypass switch when the submodule and the interface fail.