Module for protecting signal two-out-of-three logic conversion in direct-current power transmission system

Abstract

The utility model discloses a protection signal two-out-of-three logic conversion module in a direct-current power transmission system, which is characterized in that a direct-current two-out-of-three module receives a protection signal of a pole protection system through a high-speed optical fiber interface, automatically performs two-out-of-three conversion logic of the pole protection signal, and directly sends the protection signal to a circuit breaker execution mechanism through a switching value channel. Meanwhile, the converted protection signal is sent to a pole control system through a high-speed optical fiber channel; a switching value input channel and a switching value output channel of the two-out-of-three module adopt a 220V high-voltage grade design; and the output tripping signal adopts a high-capacity node design, the maximum capacity reaches 8A, and a protection execution mechanism can be directly driven.

Description

Technical Field

[0001] The utility model relates to the control and protection field in the field of ultra-high voltage direct current power transmission, and in particular to a module for three-to-two logic conversion of protection signals in a direct current power transmission system. Background Art

[0002] Each system in the existing DC transmission system is composed of three mutually redundant pole protection systems. Each pole protection system is an independent panel cabinet design, and each DC pole protection panel cabinet has complete protection functions. When the protection signals (such as tripping signals) of at least two pole protection systems in the three pole protection systems are valid, the three-out-of-two logic module will send out a protection signal, and the entire pole protection system will execute the tripping command. There are two main deficiencies in the protection signal device of the existing DC transmission system: First, in terms of communication, the traditional electrical wiring method is used, resulting in relatively weak anti-interference ability and potential instability; second, the driving capability is limited and cannot meet the needs of certain application scenarios. Therefore, it is often necessary to rely on additional output modules to enhance the driving capability, thereby increasing the complexity and cost of the system. Utility Model Content

[0003] The utility model aims to provide a module for three-to-two logic conversion of protection signals in a DC power transmission system, so as to improve the reliability of the protection system, increase the transmission distance of the system through optical fiber transmission, and enhance the anti-interference ability by increasing the voltage level.

[0004] In order to realize the above functions, the utility model designs a module for three-to-two logic conversion of protection signals in a DC power transmission system, including a pole protection system, a three-to-two logic system, a circuit breaker actuator, and a pole control system;

[0005] The pole protection system includes a pole protection system A, a pole protection system B, and a pole protection system C. The three pole protection systems are mutually redundant and are used to send a state signal and a protection signal of the DC power transmission system to the two-out-of-three logic system.

[0006] The three-out-of-two logic system includes at least one three-out-of-two logic module, which is connected to the pole protection system A, the pole protection system B, and the pole protection system C respectively, and is used to receive the status signal and protection signal sent by the three pole protection systems, and output the switch signal to the circuit breaker actuator after the three-out-of-two logic conversion, and output the optical fiber signal to the pole control system;

[0007] The circuit breaker actuator includes at least one circuit breaker, which is connected to the three-out-of-two logic system and is used to receive the switch quantity signal output by the three-out-of-two logic system and perform a tripping action according to the switch quantity signal;

[0008] The pole control system includes at least one pole control module, which is connected to the three-out-of-two logic system and is used to receive the optical fiber signal output by the three-out-of-two logic system.

[0009] As a preferred technical solution of the utility model: the pole protection system A, pole protection system B, and pole protection system C are respectively connected to the three-out-of-two logic module, and the three pole protection systems output three protection signals and three status signals to the three-out-of-two logic module respectively.

[0010] As a preferred technical solution of the present utility model: the three-out-of-two logic system includes two three-out-of-two logic modules, the input end of each three-out-of-two logic module includes a high-speed optical fiber input channel and a switch input channel, the high-speed optical fiber input channel and the switch input channel respectively correspond to receiving protection signals and status signals sent by pole protection system A, pole protection system B, and pole protection system C; the output end of each three-out-of-two logic module includes a high-speed optical fiber output channel and a switch output channel, the high-speed optical fiber output channel is connected to the pole control system, and the switch output channel is connected to the circuit breaker actuator.

[0011] As a preferred technical solution of the utility model: the circuit breaker actuator includes two circuit breakers, each circuit breaker is connected to a three-out-of-two logic module, and performs a tripping action according to a switch signal sent by the three-out-of-two logic module.

[0012] As a preferred technical solution of the utility model: the pole control system includes two pole control modules, each pole control module is respectively connected to a three-out-of-two logic module to receive optical fiber signals.

[0013] As a preferred technical solution of the utility model: the two-out-of-three logic system adds a pre-power-on signal to the switch signal sent to the circuit breaker actuator. When the switch signal and the pre-power-on signal are valid at the same time, the circuit breaker actuator performs a tripping action.

[0014] Beneficial effects: Compared with the prior art, the advantages of the utility model include:

[0015] The three-out-of-two module is used to communicate with the pole protection through high-speed optical fiber. It has strong anti-electromagnetic interference ability for control signal input and output, fast control logic state switching time, and has automatic fiber break detection and CRC data verification functions, which effectively ensures the reliability of communication. The input and output signal transmission distance is long, and a screen design can be made. The output node capacity is large and can directly drive the protection actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a circuit diagram of a module for logic conversion of three-to-two protection signals in a DC power transmission system provided according to an embodiment of the utility model;

[0017] Figure 2 It is a chassis layout diagram provided according to an embodiment of the utility model. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

[0019] The utility model provides a module for three-to-two logic conversion of protection signals in a DC power transmission system, comprising a pole protection system, a three-to-two logic system, a circuit breaker actuator, and a pole control system;

[0020] Reference Figure 1 The pole protection system includes a pole protection system A, a pole protection system B, and a pole protection system C. The three pole protection systems are mutually redundant and are used to send a state signal and a protection signal of the DC transmission system to the three-out-of-two logic system;

[0021] The pole protection system A, pole protection system B, and pole protection system C are respectively connected to the three-out-of-two logic module, and the three pole protection systems respectively output three protection signals to the three-out-of-two logic module, and output three status signals, namely, protection system OK signals (SYS_OK signals).

[0022] The three-out-of-two logic system includes at least one three-out-of-two logic module, which is connected to the pole protection system A, the pole protection system B, and the pole protection system C respectively, and is used to receive the status signal and protection signal sent by the three pole protection systems, and output the switch signal to the circuit breaker actuator after the three-out-of-two logic conversion, and output the optical fiber signal to the pole control system;

[0023] In one embodiment, the three-out-of-two logic system includes two three-out-of-two logic modules, and the input end of each three-out-of-two logic module includes a high-speed optical fiber input channel and a switch input channel, and the high-speed optical fiber input channel and the switch input channel respectively receive protection signals and status signals sent by pole protection system A, pole protection system B, and pole protection system C; the output end of each three-out-of-two logic module includes a high-speed optical fiber output channel and a switch output channel, and the high-speed optical fiber output channel is connected to the pole control system, and the switch output channel is connected to the circuit breaker actuator.

[0024] The circuit breaker actuator includes at least one circuit breaker, which is connected to the three-out-of-two logic system and is used to receive the switch quantity signal output by the three-out-of-two logic system and perform a tripping action according to the switch quantity signal;

[0025] In one embodiment, the circuit breaker actuator includes two circuit breakers, each circuit breaker is connected to a three-out-of-two logic module, and performs a tripping action according to a switch quantity signal sent by the three-out-of-two logic module.

[0026] The pole control system includes at least one pole control module, which is connected to the three-out-of-two logic system and is used to receive the optical fiber signal output by the three-out-of-two logic system.

[0027] In one embodiment, the pole control system includes two pole control modules, each pole control module is connected to a two-out-of-three logic module to receive optical fiber signals.

[0028] Reference Figure 2 ,The conversion function of the three-to-two logic module is realized by FPGA programmable logic device, ,and the software part is completed using VHDL hardware description language, ,and the programmable logic device is Xilinx's XC3S400A.

[0029] The redundant power supply module can input AC 220V, DC 220V or DC 110V power supply, and output DC 5V power supply to the backplane bus after voltage reduction and filtering, and also output power supply failure signal to the backplane bus.

[0030] The protection input signal from the pole protection system is input through the high-speed optical fiber channel, and the SYS_OK signal from the three pole protection systems is input through the switch input channel. After the SYS_OK signal and the pole protection system input signal are converted into two out of three by the FPGA programmable logic device, they are output to the pole control through the high-speed optical fiber channel. At the same time, the protection signal is sent to the switch output channel through the backplane bus, and the protection signal is output to the protection actuator.

[0031] The three-out-of-two switching principle of the three-out-of-two logic module is as follows:

[0032] The SYS_OK signal from the three-pole protection system marks the status of the three-pole protection system. When the SYS_OK signal is 1, it indicates that the three-pole protection system is working normally. When the SYS_OK signal is 0, it indicates that the three-pole protection system has a fault. Similarly, the protection signal marks the protection control signal issued by the three-pole protection system. After logic conversion, the three-out-of-two logic module outputs the protection action signal.

[0033] exist Figure 2The switch input uses a DC 220V node, and the switch output uses an AC / DC 220V node. The maximum capacity of a single node reaches 8A. The output trip signal is divided into two channel designs: a relay slow channel and an IGBT fast channel. The IGBT fast channel is realized by connecting the IGBT and the relay in parallel, and the relay zero current opening and zero current closing control strategy is adopted to effectively protect the relay. The specific control strategy is: when opening, first open the IGBT, then open the relay, and then turn off the IGBT after the relay is opened; when closing, open the IGBT first, then turn off the relay, and then turn off the IGBT after the relay is closed, so as to realize the zero current opening and zero current closing of the relay.

[0034] The optical fiber input and output channels are programmed with FPGA software to automatically detect optical fiber disconnection and perform CRC data verification.

[0035] The two-out-of-three logic system adds a pre-power-on signal to the switch signal sent to the circuit breaker actuator. When the switch signal and the pre-power-on signal are valid at the same time, the circuit breaker actuator performs a tripping action.

[0036] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A module for logic conversion of three-to-two protection signals in a DC power transmission system, characterized in that: It includes pole protection system, two-out-of-three logic system, circuit breaker actuator, pole control system; The pole protection system includes a pole protection system A, a pole protection system B, and a pole protection system C. The three pole protection systems are mutually redundant and are used to send a state signal and a protection signal of the DC power transmission system to the two-out-of-three logic system. The three-out-of-two logic system includes at least one three-out-of-two logic module, which is connected to the pole protection system A, the pole protection system B, and the pole protection system C respectively, and is used to receive the status signal and protection signal sent by the three pole protection systems, and output the switch signal to the circuit breaker actuator after the three-out-of-two logic conversion, and output the optical fiber signal to the pole control system; The circuit breaker actuator includes at least one circuit breaker, which is connected to the three-out-of-two logic system and is used to receive the switch quantity signal output by the three-out-of-two logic system and perform a tripping action according to the switch quantity signal; The pole control system includes at least one pole control module, which is connected to the three-out-of-two logic system and is used to receive the optical fiber signal output by the three-out-of-two logic system.

2. The module for logic conversion of protection signals from three to two in a DC power transmission system according to claim 1, characterized in that: The pole protection system A, the pole protection system B, and the pole protection system C are respectively connected to the three-out-of-two logic module, and the three pole protection systems output three protection signals and three status signals to the three-out-of-two logic module respectively.

3. The module for logic conversion of three-to-two protection signals in a DC power transmission system according to claim 1, characterized in that: The three-out-of-two logic system includes two three-out-of-two logic modules, and the input end of each three-out-of-two logic module includes a high-speed optical fiber input channel and a switch input channel. The high-speed optical fiber input channel and the switch input channel respectively correspond to receiving protection signals and status signals sent by pole protection system A, pole protection system B, and pole protection system C; the output end of each three-out-of-two logic module includes a high-speed optical fiber output channel and a switch output channel. The high-speed optical fiber output channel is connected to the pole control system, and the switch output channel is connected to the circuit breaker actuator.

4. The module for logic conversion of protection signals from three to two in a DC power transmission system according to claim 1, characterized in that: The circuit breaker actuator comprises two circuit breakers, each circuit breaker is connected to a three-out-of-two logic module, and performs a tripping action according to a switch quantity signal sent by the three-out-of-two logic module.

5. The module for logic conversion of protection signals from three to two in a DC power transmission system according to claim 1, characterized in that: The pole control system includes two pole control modules, each pole control module is connected to a two-out-of-three logic module to receive optical fiber signals.

6. The module for logic conversion of protection signals from three to two in a direct current transmission system according to claim 1, characterized in that: The two-out-of-three logic system adds a pre-power-on signal to the switch signal sent to the circuit breaker actuator. When the switch signal and the pre-power-on signal are valid at the same time, the circuit breaker actuator performs a tripping action.

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