KR20210147126A - High-voltage DC switch - Google Patents

Abstract

The present invention relates to a multiple input opening/closing high-voltage switch, wherein a DC transmission/distribution device and the like, in general, are configured with a circuit so that a power flowing through a plurality of DC circuits is collected into one circuit and outputted to a system and the like, and in the input part of the plurality of circuits, provides a plurality of switches that switches each DC (+) power to be cut off in case of maintenance inspection, leakage, and the like failure. Specifically, the present invention relates to in providing the high-voltage switch capable of opening/closing the multiple inputs that protects the plurality of switches through the bypass switch by providing a semiconductor-type bypass circuit for removing a high-voltage and an arc from only one circuit among the plurality of circuits or an expensive high-voltage bypass switch capable of opening/closing the high-voltage. Therefore, the system can be conveniently manufactured.

Description

High-voltage DC switch capable of switching multiple inputs

The present invention relates to a high voltage switch capable of opening and closing multiple inputs,

In general, DC transmission and distribution devices are configured such that the power flowing through a plurality of DC circuits is collected into one circuit and output to the grid, etc. To provide a plurality of switches each for switching DC (+) power,

In particular, the present invention provides a semiconductor-type bypass circuit for removing high voltage and arcing from only one circuit of the plurality of circuits or an expensive high voltage bypass switch capable of opening and closing a high voltage through the bypass switch to protect the switch of

An object of the present invention is to provide a high voltage switch capable of opening and closing multiple inputs.

Electric devices such as energy storage systems (ESS), solar power generation systems, electric vehicles, and hybrid vehicles use high-voltage DC power.

In this way, a disconnecting switch (Disconnecting Switch) for cutting off the DC power is usually installed between the electric devices using the DC power.

For example, in a photovoltaic system, solar cell modules that convert solar energy into electrical energy are connected in series, and one side of the series-connected solar cell module is connected to each other and jointly grounded (-), and the other side is connected to each other. The (+) side of each solar cell module (SM) connected in series is jointly connected with a binder. The (+) DC power string bound by the binder goes through the isolator and the leakage current breaker into the inverter, an electric device, and is converted into AC power for use.

In general, each solar cell module is composed of a plurality of solar cells. For example, when a typical solar cell module consists of 24 solar cells, the positive (+) terminal and the negative (-) terminal under sunlight It produces about 40V in between. In fact, a high voltage of 600 ~ 1000V and a current of several tens to hundreds of amps (A) flows between the (+) power string and the ground (-) of the photovoltaic array in which a plurality of solar cell modules are connected in series and parallel.

In such a photovoltaic power generation system, a disconnector is installed between the string and the inverter to cut off the high-voltage string DC power to which the string of the tanyang photovoltaic power generation array is connected for failure or maintenance.

In the conventional disconnector, a relay or a circuit breaker having a mechanical contact is usually used.

However, when switching a string (+) DC power with several hundred volts DC voltage and several tens to hundreds of amps using the mechanical contact of the disconnector, DC power does not have a current zero point like AC power. Therefore, a direct current arc is easily generated between the contact points of the disconnector, and the arc generated once lasts for a considerable time until the contact gap is sufficiently separated. The continuous arc not only shortens the life of the disconnector by melting the contact point of the disconnector, but also poses a risk of a fire accident.

So, as an amount to solve the above problems, registration number 10-1777195 is

A plurality of solar panels (S1) separately connected to a plurality of groups of circuits, a plurality of input terminals, a plurality of fuses and circuit breakers, a plurality of diodes, and an output terminal for combining the power output from the plurality of diodes into one In the connection panel,

a plurality of bypass circuits for bypassing the power input from the plurality of fuses to the plurality of diodes and outputting them to an output terminal; a plurality of bypass switches for opening and closing the bypass circuit according to a control signal from a control unit, and a measuring unit for monitoring a state of a power value flowing through the circuit;

In a state in which the circuit state is determined by the measuring unit to open and close the bypass switch, the power input to the fuse is simultaneously input to the diode and the plurality of bypass switches

During normal and equal power generation in each of the plurality of groups, any

When the measured value measured through the measuring unit in one group is out of the preset voltage range, the normally generated power is abnormally flowing.

It is determined that the reverse current flows in the circuit direction, and the bypass switch is turned off to block the reverse current by the diode, and when the power value measured through the measuring unit during monitoring is within the preset voltage range, it is determined that normal power production is It is a configuration in which the bypass switch is turned on so that power is output to the output terminal through the bypass circuit.

As described above, by providing each bypass circuit to a plurality of circuits and then providing a bypass switch to each of the bypass circuits, the product price increases. This increases the volume, increases storage and transportation costs, and has problems such as cumbersome manufacturing due to the need to connect a plurality of bypass switches.

1. Republic of Korea Patent Publication No. 10-2017-0113836 2. Republic of Korea Registration No. 10-1777195

In view of the above problems, the present invention provides a semiconductor-type bypass circuit for removing high voltage and arcing from only one circuit among the plurality of circuits or an expensive high voltage bypass switch capable of switching on and off the high voltage. An object of the present invention is to provide a high voltage switch box capable of opening and closing multiple inputs in order to protect the plurality of switches through a switch.

For example, a price at which a bypass circuit is provided to one input circuit among a plurality of input circuits, and the remaining plurality of input circuits use the bypass circuit to switch DC (+, -) power among a plurality of input circuits We want to protect the mechanical contacts of this inexpensive and easy-to-find low-voltage relay.

A detailed configuration will be described with reference to the accompanying drawings.

In the high voltage switch capable of opening and closing multiple inputs,

The electric power flowing through the plurality of DC circuits 10 is collected into one circuit and converted into a system.

Configure the circuit to output,

A bypass circuit that connects a relay 20 for turning on/off circuits respectively to the plurality of DC circuits 10 and bypasses the relay 20a connected to any one circuit 10a among the plurality of circuits 10 . (30) is connected, but a bypass switch 40 that turns on/off according to a control signal of the control unit 100 to the bypass circuit 30;

Connecting the input short circuit prevention diode (a') to the input part (30a) of the bypass circuit (30) to which the current is input to the bypass switch (40);

One side 50a of the second bypass circuit 50 is respectively connected to the plurality of circuits 10 except for the circuit 10a connecting the bypass circuit 30 and the bypass switch 40, and

The other side (50b) of the second bypass circuit (50) is combined into one, and power is output to the bypass circuit (30) between the output part (30a) of the bypass circuit (30) and the diode (a') connected as much as possible,

It consists of a diode (a) connected to each of the plurality of second bypass circuits 50 to prevent an input short circuit, and a measuring unit 130 for monitoring the state of the flowing power value of the circuit.

In a state in which the plurality of relays 20 and the bypass switch 40 connected to the plurality of circuits 10 according to the control signal of the control unit 100 are kept in an on' state

In the process of sequentially turning on/off a plurality of relays 20 for a set time through the control unit 100, the power passing through the bypass switch 40 is measured through the detection unit 140,

When the measured value measured in one circuit is out of the range of preset voltage, current, leakage current, etc., it is determined that there is a problem in the circuit 10 out of the range such as voltage, current, leakage current, 10) is to cut off the power by turning off the relay 20.

The relay corresponds to a latching relay, and the bypass switch corresponds to a MOS-FET switch.

The latching relay has a dual coil and at least one three-way switching mechanical contact and a permanent magnet capable of maintaining the circuit even when the current of the control circuit is cut off, and the three-way switching mechanical contact is the dual It is characterized in that it is opened and closed by a set (SET) signal that excites any one of the coils and a relay signal of a reset (REST).

As described above, the present invention provides a single bypass circuit for a plurality of circuits and then shares one bypass circuit with the plurality of circuits, thereby reducing the product price and providing a single bypass switch, thereby reducing the probability of failure. , by providing one bypass switch, storage and transportation costs are low due to its small volume, and it is a very beneficial invention that is convenient to manufacture by wiring only one bypass switch.

In addition, according to the present invention, the arc generation between the mechanical contacts is fundamentally suppressed by bypassing the DC power supply in parallel for a certain period of time and operating the latching relay in a state where the voltage between the mechanical contacts of the latching relay is lowered to several volts. . For this reason, even if the capacity of the latching relay is not increased, the life of the latching relay is greatly extended, and a fire accident is prevented.

In addition, by using a latching relay, the latching relay does not open and close by itself even if there is no driving voltage due to a power failure or a power supply failure. The gate of the switching device can be driven in advance for a predetermined time by using a photovoltaic output photocoupler operating with its own DC power supply. Due to this, the parallel bypass protection circuit of the semiconductor switching device operates with high reliability even if there is no additional driving voltage due to a power failure or a power supply failure.

1 is an overall flowchart of an embodiment of a high voltage DC switch capable of opening and closing multiple inputs of the present invention.
Figure 2 is a flow chart showing the operating state of the bypass switch and relay of the present invention.
3 is an explanatory diagram showing a flowchart of the present invention;
4A) is a parallel bypass protection circuit of a DC power disconnector according to an embodiment of the present invention.
B) is an operation time chart of a) of FIG. 4 .
5 is another overall flow diagram of an embodiment of a high voltage DC switch capable of opening and closing multiple inputs of the present invention.

Let's take a look at the configuration with reference to the accompanying drawings, and look at an embodiment according thereto.

In the high voltage switch capable of opening and closing multiple inputs,

The electric power flowing through the plurality of DC circuits 10 is collected into one circuit and converted into a system.

Configure the circuit to output,

A bypass circuit that connects a relay 20 for turning on/off circuits respectively to the plurality of DC circuits 10 and bypasses the relay 20a connected to any one circuit 10a among the plurality of circuits 10 . (30) is connected, but a bypass switch 40 that turns on/off according to a control signal of the control unit 100 to the bypass circuit 30;

Connecting the input short circuit prevention diode (a') to the input part (30a) of the bypass circuit (30) to which the current is input to the bypass switch (40);

One side 50a of the second bypass circuit 50 is respectively connected to the plurality of circuits 10 except for the circuit 10a connecting the bypass circuit 30 and the bypass switch 40, and

The other side (50b) of the second bypass circuit (50) is combined into one, and power is output to the bypass circuit (30) between the output part (30a) of the bypass circuit (30) and the diode (a') connected as much as possible,

It consists of a diode (a) connected to each of the plurality of second bypass circuits 50 to prevent an input short circuit, and a measuring unit 130 for monitoring the state of the flowing power value of the circuit.

Looking at the embodiment of the configuration as follows,

A diode a is connected to each of the plurality of second bypass circuits 30 and 50 , and a diode a′ is connected to one circuit 10a among the plurality of circuits 10 . That is, a diode is connected to each circuit 10 .

In this case, the power flowing to the bypass circuit and the second bypass circuit is in a state in which reverse flow is prevented because each diode is connected.

There is a measuring unit 130 that monitors the state of each power value flowing through the plurality of circuits 10, and the state of the circuit 10 is determined by the measuring unit 130, and the bypass switch ( 40) and the relay 20 connected to the plurality of circuits 10 are opened and closed.

In a state in which power is simultaneously input to the plurality of circuits 10 from a plurality of DC power input units,

When the measured value measured in any one circuit through the measuring unit 130 while normally outputting power from the plurality of circuits 10 is out of a preset voltage range, current range, or leakage current range,

Turn on the bypass switch 40 connected to the bypass circuit 30 to cut off the power flowing in the circuit 10 out of the voltage range or the current range or the leakage current range, and then turn on the voltage range or the current range or the leakage current range. The power of circuit 10 is

Turn off the relay 20 connected to the circuit 10 out of the voltage range, current range, or leakage current range while outputting to the output terminal through the bypass circuit 30 (after turning off the bypass switch) After this, the bypass switch 40 is turned off to cut off the power supply of the circuit out of the voltage range, current range, or leakage current range.

When a set time elapses after the power is cut off of the circuit 10 out of the voltage range, current range, or leakage current range, the bypass switch 40 is turned on and the power value measured through the measuring unit 130 is set in a preset voltage range Or, when it exists within the current range or the leakage current range, it is determined that the power supply is normal and the relay turned on and off so that power is output to the output terminal through the relay turned off, and then according to the control signal of the control unit 100 The bypass switch 40 is turned off.

Next, by monitoring the plurality of circuits 10 in the bypass circuit, it is possible to determine whether there is a failure.

In a state in which the plurality of relays 20 and the bypass switch 40 connected to the plurality of circuits 10 according to the control signal of the control unit 100 are kept in an on' state

In the process of sequentially turning on/off a plurality of relays 20 for a set time through the control unit 100, the power passing through the bypass switch 40 is measured through the detection unit 140,

When the measured value measured in one circuit is out of the preset voltage range or current range or leakage current range, it is determined that there is a problem in the circuit 10 out of the voltage range or current range or leakage current range, and the circuit with the problem (10)

The relay 20 is turned off to cut off the power.

An example of the configuration is as follows (refer to FIG. 5).

The power output to the output circuit 30b of the bypass switch 40 is measured through the detection unit 140 .

And when the plurality of relays 50 connected to the plurality of circuits 10 are turned off through the control unit 100 in a preset order and then turned on after a set time, they are turned off in the off process for a predetermined time.

The power of the circuit 10 is output to the output terminal through the bypass circuit 30 .

With this configuration, it is possible to check a plurality of circuits 10 through one detection unit 140, so that the manufacturing cost is low, and a problematic circuit 10 line can be easily and conveniently found, so that rapid maintenance is possible.

In the description, when the plurality of relays and the bypass switch 40 are in the on state, power input from the input unit flows in the direction of the plurality of relays, respectively.

The bypass switch is temporarily closed only when the plurality of relays 50 are operated, and after the relay operation is completed, the bypass switch is cut off (off).

This is because, when the Sanji bypass switch is OFF, the power input from the input unit flows only in the direction of the plurality of relays, respectively, and does not flow to the bypass switch 40 .

(Power moves in the direction of the relay that receives less resistance as the diode and the resistance of the bypass switch act)

In the present invention, the MOS-FET is a switching device for power circuits of various electronic devices because high-speed switching is possible and gate driving is relatively simple. The bypass switch 40 of the present invention uses a MOS-FET device (refer to Registration No. 10-1209639 for a MOS-FET gate driving circuit and driving method).

The MOS-FET device is capable of high-speed switching of high-voltage, high-current, and has a simple driving method.

However, if the current continuously flows, heat is severe and the device is destroyed.

In the present invention, the MOS-FET device is used to conduct electricity only for a short time when the arc is generated, and in the section in which current continuously flows in which heat is generated, the advantage of using the relay contact to remove heat is used.

A semiconductor-type bypass circuit to remove voltage and arc or an expensive high-voltage MOS-FET capable of opening and closing high voltage is used to switch, and when a large current is constantly flowing, the mechanical By using the contact point, the performance against heat suppression and overcurrent is improved, and the cost is reduced.

The relay 20 of the present invention is a latching relay, and the latching relay RL1 has a dual coil and at least one or more 3 switching mechanical contacts. It is preferable to connect the contacts in parallel to increase the contact capacity. and

The mechanical contact of 3-way switching can be reliably opened and closed by the set (SET) signal that excites any one of the double coils and the relay signal of the reset (REST).

In addition, by using the double-coiled latching relay (RL1) that can maintain the open/closed state without a constant driving power source, the latching relay does not open and close by itself even if there is a power failure or a power supply failure, so safety accidents such as fire are prevented. .

The latching relay RL1 (see FIG. 4) has a dual coil and at least one mechanical contact of three-way switching is preferable to increase the contact capacity by connecting the contacts in parallel, and the three-way switching mechanical contact is preferable. The contact point is any one of the double coils.

It can be reliably opened and closed by the excitation SET signal and the reset relay signal. In addition, by using the double-coiled latching relay (RL1) that can maintain the open/closed state without a constant driving power source, the latching relay does not open and close by itself even if there is a power failure or a power supply failure, thereby preventing safety accidents such as fire.

In addition, the photocoupler OP1 is preferably a photocoupler OP1 having a photocell output function capable of operating the gate drive signal with DC power (H/V INPUT & H/V OUTPUT) without external driving power supply. Unlike a general photocoupler, the photovoltaic output photocoupler OP1 has a voltage that can turn on the semiconductor switching element Q1 on the insulated output side and

A current is generated by itself to drive the semiconductor switching element Q1 without an external driving power source. Therefore, even if there is a power outage or a power supply device fails, the semiconductor switching element Q1 can be controlled, and accordingly, the DC power disconnector 100 to which the parallel bypass protection circuit of the semiconductor switching element Q1 is added can be highly reliable. can make it work

5 is an operation time chart of each component of the DC power disconnector 100, and FIG. 3 (a) is an operation time of the semiconductor switching element Q1 operated by the element control signal B/P1 of the control device. Time chart, FIG. 3B is a time chart of the operation time of the mechanical contact of the latching relay RL1 while the semiconductor switching element Q1 operates for a predetermined time, FIG. 3C is the semiconductor switching element Q1 operates, At this time, when the latching relay RL1 operates, the DC voltage applied to the mechanical contact part of the latching relay RL1 is schematically shown.

The technology related to the latching relay and the like is described in detail in Publication No. 10-2017-0113836.

Control is, as shown, the power transmitter 11 subgroups (SG1) to (SGn) of at least two or more series-connected power transmitters 11, and the power transmitter 11 subgroup Power measuring means 13 and power measurement values (P1) to (Pn) for measuring power by measuring the voltage and current of (SG1) to (SGn), and each of the power transmitting units (including the power generating unit) subgroups (SG1) to (SGn) installed in the vicinity of the solar radiation measuring sensor 14 and the measured amount of information (L1) to (Ln), and each of the power transmitter subgroups (SG1) to (SGn) at a set time interval between each other By comparing the power measurement values (P1 to Pn), if it is in an unbalanced state, it is judged as abnormal,

In addition, the amount of power (Pc) obtained by correcting the area of the power transmitter 11 small group SG1 to the power measurement value P1 of the small group SG1 and the information value L1 measured at the location A control unit 20 for determining and processing the operating state and deterioration of the power transmission unit small group (SG1) to (SGn) compared to

Communication in which the control unit 20 transmits an alarm message and data of the operation state and deterioration state of each of the power transmitting units 11 small groups SG1 to SGn to the remote communication unit 40 through the wireless communication module 30 It is characterized in that it includes means.

The small group of power transmission units SG1 includes a plurality of input units 11 and circuits 12 connected in series to obtain a predetermined voltage,

Power having a standard resistor (not shown) connected to any one line of the circuit 12 to measure a voltage from the circuit 12 and measure a current, and a voltage measuring line proportional to the current from the standard resistor It is characterized in that it includes a small group of transmission units (SG1).

The power transmitters 11 may be input to the circuit as different values of voltage, current, leakage current, etc. input from the power transmitter 11 .

The power measuring means 13 of the power transmitting unit small group SG1 periodically measures the voltage from the voltage and current measurement lines drawn from the circuit 12 of the power transmitting unit small group SG1 and A/D conversion,

A unique identification number is assigned, and the digitally converted current and voltage values and the unique identification number are transmitted to the control unit 20 according to a predetermined cycle, and converted into a power value by the calculation formula of the program inputted from the arithmetic device and stored. consists of means (13).

In addition, the control unit (microprocessor), the digital value corresponding to the A / D converted current and voltage from the power measuring means 13, a unique identification number, an interface (not shown) for receiving the amount of insolation from the insolation meter;

The digital voltage/current measurement value and the solar radiation measurement value of the unique identification number received from the interface are stored in a memory device, and a constant according to the characteristics and size of each power transmitter subgroups (SG1) to (SGn) is applied to the amount of power is corrected and calculated.

A key input unit for inputting the environment, the number of installations, calculation programs, etc. of the power transmission unit 11 of the small groups of power transmission units (SG1) to (SGn), an LCD monitor displaying key input values and calculation processing results, and a program and a control unit 20 having a storage device for storing data.

Communication means, when the operation processing result of the control unit 20 is determined to be abnormal, the wireless module 30 for transmitting to the mobile communication terminal 40 of the administrator or user using WAP;

Through the wireless module 30 and the existing mobile communication network, the unique number of the power transmission unit small group 10 to the remote manager or user's mobile communication terminal 40 through the existing mobile communication network and an alarm text determined in response to the abnormal state and stored in the storage device By transmitting the measurement data to a remote manager or user, it is possible to know from a remote location which power transmitter subgroup 10 is in an abnormal state.

Briefly describing the active operation of such a remote monitoring system, the remote monitoring

When a desired manager or user drives an application program installed in the mobile communication terminal to access the control unit 20 and transmits a status check request to the control unit 20, the control unit 20 receives a status check request from the manager or user It transmits the present or past results extracted by the system to the administrator or user's mobile communication terminal.

In this embodiment, remote monitoring is performed without additional equipment by using WAP (Wireless Application Protocol) that is installed in the control unit 20 and the manager or user's mobile communication terminal and enables wireless data communication between the two devices. can do.

WAP acts as a communication emulator. According to a predetermined protocol, the WAP converts a signal received and demodulated from the other party into meaningful information. allows you to monitor

10 circuit 20 relay
30: bypass circuit 30a: output unit
40: bypass switch 50: second bypass circuit
100: control unit 130: measurement unit
140: detection unit a': diode

Claims (4)

A high voltage switch capable of opening and closing multiple inputs,
The electric power flowing through the plurality of DC circuits 10 is collected into one circuit and converted into a system.
Configure the circuit to output,

A bypass circuit that connects a relay 20 for turning on/off circuits respectively to the plurality of DC circuits 10 and bypasses the relay 20a connected to any one circuit 10a among the plurality of circuits 10 . (30) is connected, but a bypass switch 40 that turns on/off according to a control signal of the control unit 100 to the bypass circuit 30;

Connecting the input short circuit prevention diode (a') to the input part (30a) of the bypass circuit (30) to which the current is input to the bypass switch (40);

One side 50a of the second bypass circuit 50 is respectively connected to the plurality of circuits 10 except for the circuit 10a connecting the bypass circuit 30 and the bypass switch 40, and
The other side (50b) of the second bypass circuit (50) is combined into one, and power is output to the bypass circuit (30) between the output part (30a) of the bypass circuit (30) and the diode (a') connected as much as possible,
Multiple input opening and closing, characterized in that it includes a diode (a) connected to each of the plurality of second bypass circuits (50) to prevent an input short circuit, and a measuring unit (130) for monitoring the state of the flowing power value of the circuit Possible high voltage DC switch.
According to claim 1,
In a state in which the plurality of relays 20 and the bypass switch 40 connected to the plurality of circuits 10 according to the control signal of the control unit 100 are maintained in an ON state,
In the process of sequentially turning on/off the plurality of relays 20 for a set time through the control unit 100, the power passing through the bypass switch 40 is measured through the detection unit 140,

When the measured value measured in one circuit is out of the preset voltage range, it is determined that there is a problem in the circuit 10 out of the voltage range, and
A high voltage DC switch capable of opening and closing multiple inputs, characterized in that the relay 20 is turned off to cut off the power.
The method of claim 1,
When the range values such as voltage, current, leakage current, etc. existing between the circuit 10 and the line 10 are unbalanced, it is determined that there is a problem in the line in which the unbalanced voltage, current, leakage current, etc. range is generated. A high voltage DC switch capable of opening and closing multiple inputs. The method of claim 1,
The relay 20 is configured as a latching relay, and the latching relay has a dual coil and at least one three-way switching mechanical contact, and the three-way switching mechanical contact excites any one of the double coils. A high voltage DC switch capable of opening and closing multiple inputs, characterized in that it is opened and closed by a relay signal of a SET signal and a reset signal.

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