KR20230149455A - Submodule device and modular multi-level converter - Google Patents

Abstract

The submodule device includes a submodule including a plurality of switching modules and a capacitor element, a bypass switch connected between the first output terminal and the second output terminal of the submodule, and one of the first output terminal and the second output terminal of the submodule. It includes a wireless power generator that generates wireless power based on a magnetic field formed in an output line connected to one output terminal.
The bypass switch can be controlled for switching by wireless power.

Description

Submodule device and modular multi-level converter {Submodule device and modular multi-level converter}

Embodiments relate to submodule devices and modular multilevel converters.

As industry develops and population increases, demand for electricity increases rapidly, but there are limits to electricity production.

Accordingly, a power system for stably supplying power generated at production sites to demand sites without loss is becoming increasingly important.

Typically, a power grid system may include a power generation source, a power system, a load, and a power compensation device. A power generation source refers to a place or facility that generates power, and can be understood as a producer that generates power. The power system may refer to all facilities including power lines, pylons, lightning arresters, insulators, etc. that transmit power generated from a power generation source to a load. Load refers to a place or facility that consumes power generated from a power generation source, and can be understood as a consumer who consumes power. The power compensation device may be a device that is connected to the power system and compensates for active power or reactive power depending on the supply or shortage of active power or reactive power among the power flowing into the power system.

The power compensation device is a FACTS (Flexible AC Transmission System) facility for improving power flow, grid voltage, and stability, and includes, for example, a STATCOM (STATic synchronous COMpensator) facility. STATCOM is fed into the power system in parallel and compensates for the reactive and active power required by the power system. Recently, the number of modular multilevel converter (MMC: Modular Multilevel Converter) type STATCOM facilities has been increasing. STATCOM, a modular multi-level converter type, is composed of multiple sub-modules, and these sub-modules are composed of various internal devices.

To prevent failure of multiple sub-modules, a bypass switch is provided between both output terminals of each sub-module. If the submodule fails, the bypass switch turns on and the submodule is removed.

Typically, the bypass switch operates by switching using the voltage charged in the capacitor element provided in the sub-module as a power source. In this way, power loss occurs to the extent that the charging voltage of the capacitor element of the sub-module is used as a power source for the operation of the bypass switch. STATCOM is usually equipped with hundreds of sub-modules, and the charging voltage of the capacitor element is used as a power source for the operation of the bypass switch in each sub-module, resulting in significant power loss. In addition, when the charging voltage of the capacitor element is used for the switching operation of the bypass switch, the charging voltage of the capacitor element is temporarily reduced, and the reduced charging voltage causes a plurality of switching elements provided in the sub-module or various other devices. There is a problem where the operation becomes unstable.

Meanwhile, the conventional bypass switch, as described in Domestic Patent Registration No. 10-1613812 (hereinafter referred to as Prior Art 1), has a structure in which electrical short-circuiting occurs due to the force of the gas filled inside. That is, according to prior art 1, the piston member 80 is moved by the force of the gas and a force is applied to move the insulating member, thereby electrically connecting the fixed contactor 5a and the movable contactor 5b. It becomes a short circuit state. Accordingly, problems such as circuit failures can be prevented from propagating to other circuits or electrical components.

However, in the bypass switch according to prior art 1, the time in which the piston member 80 is moved by the force of the gas is slow, so the short-circuit operation is not performed quickly, causing damage to the circuit or components.

In addition, the bypass switch according to prior art 1 is a structure in which a physical operation such as gas explosion is performed, and is disposable. In other words, if the bypass switch short-circuits once, it cannot be reused and must be replaced with a new bypass switch. Therefore, since the bypass switch must be replaced every time an accident occurs, there is a problem that replacement costs or maintenance costs are incurred.

The embodiments aim to solve the above-described problems and other problems.

Another object of the embodiment is to provide a submodule device and a modular multilevel converter that can prevent power loss in the submodule.

Another purpose of the embodiment is to provide a submodule device and a modular multilevel converter that can prevent damage to circuits or components.

Another object of the embodiment is to provide a sub-module device and a modular multi-level converter with a permanently reusable bypass switch.

Another purpose of the embodiment is to provide a sub-module device and a modular multi-level converter that can reduce electromagnetic interference (EMI) in the power system.

The technical problems of the embodiments are not limited to those described in this item and include those that can be understood through the description of the invention.

According to one aspect of the embodiment to achieve the above or other objects, a sub-module device includes: a sub-module including a plurality of switching modules and a capacitor element; a bypass switch connected between a first output terminal and a second output terminal of the sub-module; and a wireless power generator that generates wireless power based on a magnetic field formed in an output line connected to one of the first output terminal and the second output terminal of the sub-module, wherein the bypass switch is configured to: Switching can be controlled by wireless power.

The wireless power generator includes a coil unit installed on the output line to generate an induced current by the magnetic field; a battery that charges the induced current with a charging voltage; and a driver that controls switching of the bypass switch using the charging voltage.

The coil unit may be insulated from the output line. The coil unit may include a plurality of air core coils. The coil unit may include a plurality of iron core coils.

When a failure signal is received, the driver may supply the charging voltage to the bypass switch.

The sub-module device includes a sub-module control unit that manages the sub-module, and the failure signal may be received from the sub-module control unit.

The sub-module control unit communicates with the upper controller, and the failure signal may be received from the upper controller via the sub-module control unit.

The driver may include a voltage modulator that modulates the charging voltage into a modulation voltage; A detection unit that detects whether the failure signal or recovery signal is received; and an output control unit that controls output of the modulation voltage to the bypass switch depending on whether reception of the failure signal or recovery signal is detected.

The driver may block supply of the modulation voltage when the return signal is received.

The wireless power generator includes a first voltage converter that converts the induced current into a first direct current voltage; and a second voltage converter converting the first direct current voltage to a second direct current voltage.

The battery may be connected between the first voltage converter and the second voltage converter. The battery may be connected between the second voltage converter and the driver.

The bypass switch may include a semiconductor switching element.

According to another aspect of the embodiment, the modular multilevel converter includes a plurality of sub-module devices connected to the power system, wherein the plurality of sub-module devices each include a plurality of switching modules and a capacitor element - Each sub-module of the plurality of sub-module devices is connected to each other in series; a bypass switch connected between a first output terminal and a second output terminal of the sub-module; and a wireless power generator that generates wireless power based on a magnetic field formed in an output line connected to one of the first output terminal and the second output terminal of the sub-module, wherein the bypass switch is configured to: Switching can be controlled by wireless power.

The wireless power generator includes a coil unit installed on the output line to generate an induced current by the magnetic field; a battery that charges the induced current with a charging voltage; and a driver that controls switching of the bypass switch using the charging voltage.

When a failure signal is received, the driver may supply the charging voltage to the bypass switch.

In the embodiment, power damage to the sub-module device can be prevented by controlling switching of the bypass switch using a magnetic field formed in an output line connected to the power system rather than using the voltage of the capacitor element of the sub-module.

In the embodiment, by using a semiconductor switching element as a bypass switch, rapid short-circuiting is possible and damage to circuits or electronic components within the submodule device can be prevented.

In the embodiment, by using a semiconductor switching element as a bypass switch, permanent reuse is possible and bypass replacement costs can be reduced.

The embodiment uses the magnetic field formed in the output line connected to the power system to control switching of the bypass switch, thereby reducing electromagnetic interference (EMI) formed in the power system or output line, preventing signal distortion due to electromagnetic interference. Malfunction due to malfunction can be prevented.

Additional scope of applicability of the embodiments will become apparent from the detailed description that follows. However, since various changes and modifications within the spirit and scope of the embodiments may be clearly understood by those skilled in the art, the detailed description and specific embodiments, such as preferred embodiments, should be understood as being given by way of example only.

1 shows a power grid system according to an embodiment.
Figure 2 shows a modular multilevel converter according to an embodiment.
Figure 3 shows the first sub-module device of Figure 2;
FIG. 4 shows the wireless power generation unit of FIG. 3.
FIG. 5 shows the wireless power generation unit of FIG. 3 in detail.
Figure 6 is a block diagram showing the driving unit of Figure 5.
Figure 7 is a signal waveform diagram of the embodiment.

Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. However, identical or similar components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted. The suffixes 'module' and 'part' for components used in the following description are given or used interchangeably in consideration of ease of specification preparation, and do not have distinct meanings or roles in themselves. Additionally, the attached drawings are intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical idea disclosed in this specification is not limited by the attached drawings. Additionally, when an element such as a layer, region or substrate is referred to as being 'on' another component, this includes either directly on the other element or there may be other intermediate elements in between. do.

1 shows a power grid system according to an embodiment.

As shown in FIG. 1, in the power system according to the embodiment, a power plant (not shown), a substation (not shown), STATCOM (20), load (not shown), etc. may be connected through the power system (10). .

Power generated by the power plant may be transmitted to the load through the power system 10. A power plant is a place that generates electricity and may include, for example, a thermal power plant, a hydroelectric power plant, a nuclear power plant, or a renewable power plant such as solar power.

A substation may be a place that adjusts the voltage of power transmitted from a power plant through the power system 10.

STATCOM (20) regulates the voltage of the power system (10), supplies reactive power to the power system (10), or absorbs reactive power from the power system (10), and can be installed in a substation or load side. there is.

STATCOM (20) is connected to the upper controller (30) through communication and can exchange information. For example, various status information may be detected in the STATCOM (20) and transmitted to the upper controller (30). For example, the upper controller 30 transmits a control signal or command to the STATCOM 20, and the STATCOM 20 can be controlled according to the control signal or command.

Since the communication method between the STATCOM 20 and the upper controller 30 is widely known, detailed description is omitted.

Figure 2 shows a modular multilevel converter according to an embodiment.

Referring to FIG. 2, the modular multi-level converter 20A according to the embodiment may include a plurality of sub-module devices 21-1 to 21-n and a valve control unit 23.

Each of the plurality of sub-module devices 21-1 to 21-n may include a sub-module, a bypass switch, and a wireless power generator 200. For example, one side of the first sub-module (SM1 in FIG. 3) among the plurality of sub-modules (SM1, SM2) is connected to the power system 10, and one side of the last sub-module among the plurality of sub-modules (SM1, SM2) is connected to the power system 10. It is grounded, and the plurality of sub-modules SM1 and SM2 can be directly connected to each other. Therefore, by controlling the voltage of each of the plurality of sub-modules (SM1, SM2), the voltage of the power system 10 is adjusted, input (or supply) reactive power to the power system 10, or reactive power is supplied from the power system 10. Can absorb power.

Hereinafter, the first sub-module device 21-1 among the plurality of sub-module devices 21-1 to 21-n will be described in detail with reference to FIG. 3. Since each of the remaining submodule devices 21-2 to 21-n also has the same configuration as that of FIG. 3, it can be easily understood from FIG. 3.

Referring to FIG. 3, the first sub-module device 21-1 may include a first sub-module SM1, a bypass switch 100, a wireless power generator 200, and a sub-module control unit 22. there is.

The first sub-module SM1 may include a plurality of switching modules S1 to S4 and a capacitor element C. The voltage of the power system 10 may be charged to the capacitor element C.

For example, the output voltage of the first sub-module SM1 may be adjusted based on the voltage charged in the capacitor element C.

For example, the voltage charged in the capacitor element C can be used as a power source. That is, the voltage charged in the capacitor element C can be used as a power source for the sub-module control unit 22. That is, the sub-module control unit 22 can be driven by the voltage provided from the capacitor element C.

The sub-module control unit 22 may manage and/or control electronic components installed in the first sub-module SM1. For example, the sub-module control unit 22 may be driven by the voltage provided from the capacitor element C to generate gate signals for controlling the plurality of switching modules S1 to S4. In response to this gate signal, the switching element of each switching module (S1 to S4) may be turned on/off. For example, the sub-module control unit 22 includes a plurality of switching modules (S1 to S4), a capacitor element (C), a cell power supply (not shown), and a resistance element (not shown) of the first sub-module device 21-1. ) receives status information of each switch, capacitor element (C), resistor element, and self-power supply of a plurality of switching modules (S1 to S4) through communication, and sends various status information via the valve control unit 23. It can be transmitted to the upper controller 30. For example, the sub-module control unit 22 may adjust gate signals to be supplied to each switching module (S1 to S4) based on various status information and command values provided from the upper controller 30, but this is not limited.

Meanwhile, according to the related art, since the voltage charged in the capacitor element of the first sub-module is used as a power source for the operation of the bypass switch, power loss may occur.

In addition, according to the related art, the bypass switch is operated by a gas type, and if it is short-circuited once, it cannot be reused, increasing the cost of replacing parts.

In addition, according to the related art, since the bypass switch is operated by a gas method, it takes a long time to short-circuit, and damage to surrounding circuits or components may not be prevented.

In order to solve the conventional problem, the embodiment may operate the bypass switch 100 using wireless power obtained from a magnetic field formed in the power system 10 as a power source.

Referring again to FIG. 3, the bypass switch 100 may be connected between the first output terminal 301 and the second output terminal 302 of the first sub-module SM1. For example, the first output terminal 301 may be connected to the power system 10 via the output line 310. The second output terminal 302 may be connected to the first output terminal 301 of the second sub module SM2 of the second sub module device 21-2. The second sub-module device 21-2 may also have a bypass switch 100 connected between the first output terminal 301 and the second output terminal 302 of the second sub-module SM2.

The bypass switch 100 of the embodiment may include a semiconductor switching element. The semiconductor switching element may be an IGBT switch, an NMOS transistor switch, or a PMOS transistor switch, but is not limited thereto.

For example, one terminal of the bypass switch 100 may be connected to the first output terminal 301, and the other terminal may be connected to the second output terminal 302. In addition, the bypass switch 100 may be provided with a gate terminal (G) as an input terminal. When a high level gate voltage (GV) is input to the gate terminal (G), the bypass switch 100 may be short-circuited.

The voltage of the capacitor element C in the first sub-module SM1 is set to a predetermined value between the first output terminal 301 and the second output terminal 302 by controlling the switching of each switch of the plurality of switching modules S1 to S4. It can be output as voltage. If the bypass switch 100 is short-circuited, the voltage between the first output terminal 301 and the second output terminal 302 of the first sub-module SM1 may be 0V. That is, there is no voltage contributing to voltage control of the power system 10 in the first sub-module device 21-1.

The bypass switch 100 may be operated by the gate voltage (GV) provided from the wireless power generator 200.

For example, the wireless power generator 200 may be installed adjacent to the output line 310 connected to the first output terminal 301 of the first sub-module SM1. In the drawing, the wireless power generator 200 is shown as being installed adjacent to the first output terminal 301 of the first sub-module SM1, but it may also be installed adjacent to the second output terminal 302.

Since the output line 310 is connected to the power system 10 and a high current flows, a magnetic field may be formed around the output line 310 by the high current.

The wireless power generator 200 generates a gate voltage (GV) based on the magnetic field formed around the output line 310 and can be used to control switching of the bypass switch 100. For example, the wireless power generator 200 generates wireless power based on a magnetic field formed around the output line 310, and the bypass switch 100 can be controlled to switch using this wireless power.

Hereinafter, the wireless power generator 200 will be described in detail with reference to FIGS. 4 and 5.

FIG. 4 shows the wireless power generation unit of FIG. 3. FIG. 5 shows the wireless power generation unit of FIG. 3 in detail.

Referring to FIGS. 4 and 5 , the wireless power generator 200 may include a coil unit 210, a battery 230, and a driver 250.

The coil unit 210 is installed on the output line 310 and can generate an induced current (i ₂ ) by a magnetic field. A grid current (I _Grid ) caused by a transmission voltage (V _ac ), which is an alternating current voltage, may flow through the output line 310 connected to the grid line. Grid current (I _Grid ) may be current flowing in a smart grid environment. Since the grid current (I _Grid ) flows alternately left and right in the output line 310 due to the transmission voltage (V _ac ), a magnetic field may be formed around the output line 310.

Since the coil unit 210 is installed on the output line 310, an induced current (i ₂ ) may be generated in the coil unit 210 by the magnetic field formed in the output line 310.

When a high voltage or high current flows through the output line 310, the coil unit 210 may be damaged by the high voltage or high current, and the coil unit 210 may be insulated from the output line 310.

For example, the coil unit 210 may include a plurality of air core coils wound. For example, the coil unit 210 may include a plurality of wound iron core coils. An air core coil or an iron core coil may be wound around the output line 310. Accordingly, the coil unit 210 and the output line 310 can be insulated by air or an iron core. In addition, materials such as insulators, ferrite, sandust, and silicon may be used as insulating materials.

The battery 230 may be charged by an induced current (i ₂ ) generated in the coil unit 210 to a charging voltage (V _bat ). A super capacitor element, etc. may be used instead of the battery 230.

The driver 250 may control switching of the bypass switch 100 using the charging voltage (V _bat ) of the battery 230. For example, the driver 250 may control switching of the bypass switch 100 by using the charging voltage (V _bat ) of the battery 230 as the gate voltage (GV). That is, the bypass switch 100 may be turned on (or short-circuited) by a high-level gate voltage (GV). When the gate voltage (GV) and the charging voltage (V _bat ) of the battery 230 are different, the driver 250 may modulate the charging voltage (V _bat ) of the battery 230 to the gate voltage (GV).

When a fault signal (FS: Fault Signal) is received, the driver 250 supplies the charging voltage (V _bat ) of the battery 230 to the bypass switch 100, and supplies the charging voltage (V _bat ) of the battery 230 to the bypass switch 100. ) The bypass switch 100 may be short-circuited.

As an example, the failure signal FS may be received from the sub-module control unit 22. As described above, the sub-module control unit 22 controls each switch, capacitor element (C), resistor element, and self-power supply of the plurality of switching modules (S1 to S4) of the first sub-module device (21-1). Based on the status information, it is determined whether the first sub-module device 21-1 is broken, and if the first sub-module device 21-1 is broken as a result of the determination, a fault signal FS is transmitted to the driver 250. You can. When receiving a failure signal (FS) from the sub-module control unit 22, the driver 250 uses the charging voltage (V _bat ) of the battery 230 as the high-level gate voltage (GV) to the bypass switch 100. By supplying the bypass switch 100 with a high-level gate voltage (GV), it is possible to prevent damage to various circuits or electronic components within the first sub-module device 21-1.

As another example, the failure signal FS may be received from the upper controller 30 via the sub-module control unit 22. As described above, the sub-module control unit 22 controls each switch, capacitor element (C), resistor element, and self-power supply of the plurality of switching modules (S1 to S4) of the first sub-module device (21-1). The status information can be transmitted to the upper controller 30 via the valve control unit (23 in FIG. 2). The upper controller 30 can receive status information not only for the first sub-module device 21-1 but also for each of the remaining sub-module devices 21-2 to 21-n.

The upper controller 30 determines whether there is a failure in all sub-module devices or individual sub-module devices based on the status information of each of these sub-module devices 21-1 to 21-n, and selects the sub-module determined to be faulty. Failure signal information is included to correspond to the devices 21-1 to 21-n and provided to the submodule control unit 22 of the corresponding submodule devices 21-1 to 21-n via the valve control unit 23. You can. If the sub-module control unit 22 of the first sub-module device 21-1 receives failure signal information from the upper control unit, the corresponding upper controller 30 generates a failure signal (FS) (or control signal) is transmitted to the driver 250, and the driver 250 supplies the charging voltage (V _bat ) of the battery 230 to the bypass switch 100 based on the corresponding failure signal (FS) to switch the bypass switch. (100) may be short-circuited.

As shown in FIG. 6, the driver 250 may include a voltage modulator 251, a detection unit 252, and an output control unit 253.

The voltage modulator 251 may modulate the charging voltage (V _bat ) of the battery 230 into a modulation voltage (MV). The modulation voltage may be a high-level gate voltage (GV) to be supplied to the bypass switch 100. When the charging voltage (V _bat ) of the battery 230 is different from the high-level gate voltage (GV), the charging voltage (V _bat ) of the battery 230 is changed by the voltage modulator 251 to the high-level gate voltage ( It can be modulated with the same modulation voltage as GV).

The detection unit 252 can detect whether a failure signal (FS) or a return signal (RS) is received. Among the plurality of input terminals of the driver 250, a specific input terminal may be assigned as a terminal to which a fault signal (FS) or a recovery signal (RS) is input. In this case, a specific input terminal may serve as the sensing unit 252. It may be detected that the fault signal (FS) or recovery signal (RS) is received at the same time that the fault signal (FS) or recovery signal (RS) is input to a specific input terminal.

The return signal RS is a signal for releasing the short circuit of the bypass switch 100, and the bypass switch 100 is short-circuited, i.e., disconnected, so that the first sub-module device 21-1 can operate normally. . The return signal (RS) may be generated by the upper controller (30 in FIG. 1) or the sub-module control unit (22 in FIG. 3), but this is not limited.

The output control unit 253 may control the output of the modulation voltage of the voltage modulator 251 to the bypass switch 100 depending on whether reception of the failure signal FS or the recovery signal RS is detected.

For example, when the reception of the fault signal FS is detected, that is, when the fault signal FS has a high level (FIG. 7), the output control unit 253 modulates the modulation voltage as the high level gate voltage GV. It can be supplied to the bypass switch 100. Accordingly, the bypass switch 100 is short-circuited by the high-level gate voltage (GV), and the connection with the power system 10 is cut off, causing the first sub-module device 21-1 to be disconnected from the high-level gate voltage (GV). Damage to circuits or electronic components can be prevented.

For example, when the reception of the return signal RS is detected, that is, when the return signal RS has a high level (FIG. 7), the output control unit 253 switches the low-level gate voltage GV to the bypass switch ( 100) can be supplied. Alternatively, when reception of the return signal RS is detected, the output control unit 253 may block the supply of the modulation voltage, thereby not supplying any voltage to the bypass switch 100.

The return signal (RS) is generated after the failure signal (FS) is generated, and when the bypass switch 100 is short-circuited by the failure signal (FS), the bypass switch 100 is disconnected by the return signal (RS). The short circuit can be released. Accordingly, as the short-circuit of the bypass switch 100 is released, each switch of the plurality of switching modules S1 to S4 of the first sub-module device 21-1 is controlled to switch to control the voltage of the power system 10. It may contribute to the supply of reactive power to the power system 10 or to the absorption of reactive power from the power system 10 .

Meanwhile, referring again to FIGS. 4 and 5 , the wireless power generator 200 may include a first voltage converter 220 and a second voltage converter 240.

The first voltage converter 220 may convert the induced current (i ₂ ) generated in the coil unit 210 into a first direct current voltage.

An induced voltage (V _ac2 ) may be generated based on the induced current (i ₂ ) by the inductor (L2) and the capacitor element (C2) provided in the coil unit 210. This induced voltage (V _ac2 ) may be an alternating voltage.

The first voltage converter 220 may be composed of a plurality of diodes D1 to D4, but this is not limited. The induced voltage V _ac2 may be converted into a first direct current voltage by the plurality of diodes D1 to D4 of the first voltage converter 220. The first direct current voltage may be charged to the battery 230. For example, since the battery 230 is fully charged with the first direct current voltage, the first direct current voltage may be output as the charging voltage (V _bat ) of the battery 230, but this is not limited.

The second voltage converter 240 may convert the first direct current voltage to the second direct current voltage. The second voltage converter 240 may be composed of a diode D5 and a switching element Q connected in series to the diode D5. The first direct current voltage may be converted into a second direct current voltage by the diode D5 and the switching element Q of the second voltage converter 240. The second direct current voltage is a voltage required by the driver 250, and when the driver 250 requires the charging voltage (V _bat ) of the battery 230 as is, the second voltage converter 240 may be omitted.

Although not shown, Ldc is an inductor and may serve to prevent the output voltage from the second voltage converter 240 from being suddenly supplied.

Although not shown, L1 may refer to an inductor inherent in the output line 310.

Meanwhile, the battery 230 may be connected between the first voltage converter 220 and the second voltage converter 240. Although not shown, the battery 230 may be connected between the second voltage converter 240 and the driver 250.

The above detailed description should not be construed as restrictive in any respect and should be considered 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.

10: Power system
20: STATCOM
20A: Modular multilevel converter
21-1 to 21-n: Submodule devices
22: Submodule control unit
23: Valve control unit
30: Upper controller
100: bypass switch
200: wireless power generation unit
210: Coil unit
220: first voltage converter
230: battery
240: second voltage converter
250: driving unit
251: voltage modulation unit
252: detection unit
253: Output control unit
301, 302: output stage
310: output line
S1, S2, S3, S4: switching modules
SM1, SM2: Submodule
G: Gate terminal
C: Capacitor element
V _ac : transmission voltage
I _Grid : grid current
FS: Fault signal
RS: return signal
GV: gate voltage
V _bat : charging voltage

Claims (16)

A sub-module including a plurality of switching modules and capacitor elements;
a bypass switch connected between a first output terminal and a second output terminal of the sub-module; and
It includes a wireless power generator that generates wireless power based on a magnetic field formed in an output line connected to one of the first output terminal and the second output terminal of the sub-module,
The bypass switch is,
Switching controlled by the wireless power
Submodule device. According to paragraph 1,
The wireless power generator,
a coil unit installed on the output line to generate an induced current by the magnetic field;
a battery that charges the induced current with a charging voltage; and
A driving unit that controls switching of the bypass switch using the charging voltage; comprising a.
Submodule device. According to paragraph 2,
The coil portion is insulated from the output line.
Submodule device. According to paragraph 2,
The coil unit includes a plurality of wound air core coils or iron core coils.
Submodule device. According to paragraph 2,
The driving unit,
When a fault signal is received, the charging voltage is supplied to the bypass switch.
Submodule device. According to clause 5,
Includes a sub-module control unit that manages the sub-module,
The failure signal is received from the submodule control unit.
Submodule device. According to clause 5,
The sub-module control unit communicates with the upper controller,
The failure signal is received from the upper controller via the sub-module control unit.
Submodule device. According to clause 5,
The driving unit,
a voltage modulator that modulates the charging voltage into a modulation voltage;
A detection unit that detects whether the failure signal or recovery signal is received; and
An output control unit that controls the output of the modulation voltage to the bypass switch depending on whether reception of the failure signal or recovery signal is detected.
Submodule device. According to clause 8,
The driving unit,
When the return signal is received, blocking the supply of the modulation voltage
Submodule device. According to paragraph 2,
The wireless power generator,
a first voltage converter converting the induced current into a first direct current voltage; and
A second voltage converter converting the first direct current voltage to a second direct current voltage.
Submodule device. According to clause 10,
The battery is connected between the first voltage converter and the second voltage converter.
Submodule device. According to clause 10,
The battery is connected between the second voltage converter and the driving unit.
Submodule device. According to paragraph 1,
The bypass switch is,
Containing a semiconductor switching element
Submodule device. Includes a plurality of submodule devices connected to the power system,
Each of the plurality of submodule devices,
A sub-module including a plurality of switching modules and a capacitor element - each sub-module of the plurality of sub-module devices is connected in series to each other;
a bypass switch connected between a first output terminal and a second output terminal of the sub-module; and
It includes a wireless power generator that generates wireless power based on a magnetic field formed in an output line connected to one of the first output terminal and the second output terminal of the sub-module,
The bypass switch is,
Switching controlled by the wireless power
Modular multilevel converter. According to clause 14,
The wireless power generator,
a coil unit installed on the output line to generate an induced current by the magnetic field;
a battery that charges the induced current with a charging voltage; and
A driving unit that controls switching of the bypass switch using the charging voltage; comprising a.
Modular multilevel converter. According to clause 15,
The driving unit,
When a fault signal is received, the charging voltage is supplied to the bypass switch.
Modular multilevel converter.

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