Secondary Terminal Test Circuit and Equipment for Distribution Network

Abstract

The present invention discloses a secondary terminal test circuit and device for a distribution network. The circuit includes a line power generation module, a line working environment simulation module, a switch body module, and a port module. The line power generation module is used to provide a three-phase power supply. The line working environment simulation module is used to simulate several input scenarios of the three-phase power supply, and is also used to implement the function of inputting or withdrawing zero-sequence voltage and inputting or withdrawing zero-sequence current. The switch body module is used to simulate the working state and fault conditions of a circuit breaker. The port module is used to be electrically connected to the secondary terminal of the distribution network. The present invention has the advantages of good portability, high integration, high reproducibility, and low cost, and can comprehensively and accurately test the functions and characteristics of the distribution terminal.

Description

Technical Field

[0001] The present invention relates to the technical field of distribution terminal testing, and particularly to a secondary terminal testing circuit and device for a distribution network. Background Art

[0002] During the research and development, testing, production, and joint debugging processes of secondary terminal equipment for distribution networks, it is necessary to test functions such as logic, protection, and measurement of intelligent distribution terminals. In this process, common testing equipment solutions include a relay protection tester (hereinafter referred to as a relay protection instrument) combined with a real circuit breaker, an automated testing platform, a relay protection instrument combined with a simulated circuit breaker, etc.

[0003] Among them, the combination of a relay protection instrument and a real circuit breaker is the testing solution closest to the actual usage environment, so it is usually used as the testing solution during the factory inspection and joint debugging of distribution terminals. However, the relay protection instrument is costly, the primary switch is large in volume and heavy in weight, making it difficult to move, which causes certain inconvenience in the research and development and testing links. Moreover, increasing the primary switch usually requires cooperation with step-up transformers, current boosters, etc., and special attention needs to be paid to the personal safety of operators.

[0004] The automated testing platform is highly automated and intelligent, and can basically handle all logic and function tests. However, its cost is higher and its popularity is very low, so it is usually used in the research and development testing link and is not suitable for simple tests during unit testing and software development.

[0005] The solution of combining a relay protection instrument with a simulated circuit breaker is the most flexible solution, which uses a simulated circuit breaker to replace the real circuit breaker. It occupies a small area and is light in weight, and can build a test environment anytime and anywhere, and can meet most requirements of manufacturers of secondary terminal equipment for distribution networks. However, the simulated circuit breaker can only simulate some working conditions, and cannot simulate actual applications such as circuit breaker failures and line failures. Coupled with the high cost of the relay protection instrument, it also has certain limitations.

[0006] In view of the above advantages and disadvantages of the applications, if there is a testing platform with low cost, portability, closer to the actual usage environment, greater expression of circuit breaker and line failures, and capable of outputting three-phase voltage and current, it will be an effective supplement to the testing equipment solution for secondary terminal equipment, can reduce the time for building the test environment, and is particularly suitable for some relatively simple unit testing and function testing scenarios. Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, the present invention provides a secondary terminal testing circuit for a distribution network, which can simultaneously have the advantages of good portability, high integration, high reproducibility, and low cost, and accurately test the functions and characteristics of a distribution terminal.

[0008] The present invention also provides a secondary terminal test device for a distribution network having the above secondary terminal test circuit for a distribution network.

[0009] According to an embodiment of the first aspect of the present invention, the secondary terminal test circuit for a distribution network includes:

[0010] A line power generation module for providing a three-phase power supply;

[0011] A line working environment simulation module electrically connected to the line power generation module, for simulating several input scenarios of the three-phase power supply, and also for implementing the function of inputting or withdrawing zero-sequence voltage and inputting or withdrawing zero-sequence current;

[0012] A switch body module electrically connected to the line working environment simulation module and also electrically connected to the line power generation module, for simulating the working state and fault conditions of a circuit breaker;

[0013] A port module electrically connected to the switch body module and also for electrically connecting to the secondary terminal of the distribution network.

[0014] In some embodiments of the present invention, the line power generation module includes:

[0015] A DC power supply for providing a line power supply and a control power supply;

[0016] A single-chip microcomputer electrically connected to the DC power supply, for receiving and adjusting the line power supply;

[0017] A voltage three-phase inverter, the input end of which is electrically connected to the single-chip microcomputer, and the output end of which is electrically connected to the line working environment simulation module, for converting the line power supply into a three-phase AC voltage and outputting it to the line working environment simulation module;

[0018] A current three-phase inverter, the input end of which is electrically connected to the single-chip microcomputer, and the output end of which is electrically connected to the switch body module, for converting the line power supply into a three-phase AC current and outputting it to the switch body module;

[0019] A voltage amplitude adjustment knob electrically connected to the single-chip microcomputer;

[0020] A current amplitude adjustment knob electrically connected to the single-chip microcomputer;

[0021] A frequency adjustment knob electrically connected to the single-chip microcomputer.

[0022] In some embodiments of the present invention, the line working environment simulation module includes:

[0023] The first relay, the input end of the first relay is electrically connected to the output end of the three-phase voltage inverter, and the output end of the first relay is electrically connected to the input end of the switch body module. The first relay is used to simulate the voltage input scenario on the incoming line side of the circuit breaker;

[0024] The first self-locking button, the first self-locking button is electrically connected to the control end of the first relay;

[0025] The second relay, the input end of the second relay is electrically connected to the output end of the three-phase voltage inverter, and the output end of the second relay is electrically connected to the output end of the switch body module. The second relay is used to simulate the voltage input scenario on the outgoing line side of the circuit breaker;

[0026] The second self-locking button, the second self-locking button is electrically connected to the control end of the second relay.

[0027] In some embodiments of the present invention, the line working environment simulation module further includes:

[0028] The zero-voltage switching-on and -off self-locking switch, one end of the zero-voltage switching-on and -off self-locking switch is electrically connected to one phase of the output end of the three-phase voltage inverter, and the other end of the zero-voltage switching-on and -off self-locking switch is electrically connected to the input ends of the first relay and the second relay;

[0029] The zero-current switching-on and -off self-locking switch, one end of the zero-current switching-on and -off self-locking switch is electrically connected to one phase of the output end of the three-phase current inverter, and the other end of the zero-current switching-on and -off self-locking switch is electrically connected to the input end of the third relay.

[0030] In some embodiments of the present invention, the switch body module includes:

[0031] The third relay, which is used to simulate a three-phase current circuit breaker. The input end of the third relay is electrically connected to the three-phase current inverter, and the output end of the third relay is electrically connected to the port module;

[0032] The fourth relay, which is used to simulate a three-phase voltage circuit breaker. The input end of the fourth relay is electrically connected to the output end of the first relay, and the input end of the fourth relay is also electrically connected to the port module. The output end of the fourth relay is electrically connected to the output end of the second relay, and the output end of the fourth relay is also electrically connected to the port module;

[0033] The fifth relay, the input end of the fifth relay is electrically connected to the control power supply, and the output end of the fifth relay is electrically connected to the control ends of the third relay and the fourth relay. The fifth relay adopts a double-coil magnetic latching relay.

[0034] In some embodiments of the present invention, the switch body module further includes:

[0035] An in-situ logic module, the output end of the in-situ logic module is electrically connected to the control end of the fifth relay;

[0036] An in-situ closing button for the switch, one end is electrically connected to the control power supply, and the other end is electrically connected to the input end of the in-situ logic module;

[0037] An in-situ tripping button for the switch, one end is electrically connected to the control power supply, and the other end is electrically connected to the input end of the in-situ logic module;

[0038] A remote / local switching button, one end is electrically connected to the control power supply, and the other end is electrically connected to the input end of the in-situ logic module;

[0039] A current-with-flow-in-trip-position button, one end is electrically connected to the control power supply, and the other end is electrically connected to the control end of the third relay;

[0040] A normally-closed button for switch refusal to operate, one end is electrically connected to the control power supply, and the other end is electrically connected to the input end of the in-situ logic module;

[0041] A knob for adjusting the switch uncharged time, which is electrically connected to the input end of the in-situ logic module;

[0042] A switch uncharged indicator light, which is electrically connected to the output end of the in-situ logic module.

[0043] In some embodiments of the present invention, the port module includes:

[0044] An incoming-line voltage sampling socket, which is electrically connected to the input end of the fourth relay and is also used for electrical connection with the secondary terminal of the distribution network;

[0045] An outgoing-line voltage sampling socket, which is electrically connected to the output end of the fourth relay and is also used for electrical connection with the secondary terminal of the distribution network;

[0046] A current sampling socket, which is electrically connected to the output end of the third relay and is also used for electrical connection with the secondary terminal of the distribution network;

[0047] A switch tripping position remote signaling terminal, which is electrically connected to the output end of the in-situ logic module and is also used for electrical connection with the secondary terminal of the distribution network;

[0048] A switch closing position remote signaling terminal, which is electrically connected to the output end of the in-situ logic module and is also used for electrical connection with the secondary terminal of the distribution network;

[0049] The remote closing terminal of the switch is electrically connected to the output end of the local logic module and is also used for being electrically connected to the secondary terminal of the distribution network;

[0050] The remote tripping terminal of the switch is electrically connected to the output end of the local logic module and is also used for being electrically connected to the secondary terminal of the distribution network;

[0051] The uncharged position terminal of the switch is electrically connected to the output end of the local logic module and is also used for being electrically connected to the secondary terminal of the distribution network.

[0052] In some embodiments of the present invention, a meter module is further provided, and the meter module includes:

[0053] A three-phase AC voltmeter is arranged between the voltage three-phase inverter and the line working environment simulation module;

[0054] A three-phase AC ammeter is arranged between the current three-phase inverter and the switch body module.

[0055] The secondary terminal test equipment of the distribution network according to the second aspect embodiment of the present invention includes:

[0056] A housing;

[0057] An operation panel is arranged on one side of the housing and is used for being electrically connected to the secondary terminal of the distribution network;

[0058] A circuit board module is arranged in the housing and is electrically connected to the operation panel. The circuit board module is provided with the secondary terminal test circuit of the distribution network as described in the above aspect embodiment, and the operation panel is further used for adjusting the working state of the circuit board module.

[0059] In some embodiments of the present invention, the circuit board module includes:

[0060] An operation panel PCB is electrically connected to the operation panel, and the operation panel PCB is provided with a port module;

[0061] A DC power supply and inverter control board is electrically connected to the operation panel PCB, and the DC power supply and inverter control board is used for forming a line power generation module;

[0062] A main control board is electrically connected to the power supply and inverter control board and is also electrically connected to the operation panel PCB. The main control board is provided with a line working environment simulation module and a switch body module.

[0063] The secondary terminal circuit and equipment of the distribution network according to the embodiments of the present invention have at least the following beneficial effects: By setting up a line power generation module, low-voltage direct current can be converted into three-phase four-wire alternating current that simulates the actual working conditions of the distribution network terminal, which can provide power for equipment such as the tested distribution terminal without the need for an additional power source; By setting up a line working environment simulation module and a switch body module electrically connected thereto, the actual working conditions of the primary switch can be comprehensively simulated. It is equivalent to moving the on-site environment to the laboratory. The two inverter modules inside are simulated as the power output of the low-voltage side of the substation and can simulate the situation of power coming from both sides of the primary switch; By setting up a port module, the connection ports of the present invention with the distribution terminal cover all the functions of the real primary switch. For the distribution terminal, the present invention is a real circuit breaker. The interaction between the present invention and the operator not only includes the operation of the simulated circuit breaker but also the operation of the line working conditions; By integrating all the modules required for testing into a circuit board and placing them in the secondary terminal equipment of the distribution network, the portability of the present invention is improved and the cost is reduced.

[0064] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Brief Description of the Drawings

[0065] The following further describes the present invention in conjunction with the drawings and embodiments, where:

[0066] Figure 1 It is a module connection diagram of the secondary terminal test circuit of the distribution network according to the embodiments of the present invention;

[0067] Figure 2 It is an electrical schematic diagram of the secondary terminal test circuit of the distribution network according to the embodiments of the present invention;

[0068] Figure 3 It is an overall structure diagram of the secondary terminal test equipment of the distribution network according to the embodiments of the present invention;

[0069] Figure 4 It is an exploded view of the structure of the secondary terminal test equipment of the distribution network according to the embodiments of the present invention;

[0070] Figure 5 It is a panel diagram of the secondary terminal test equipment of the distribution network according to the embodiments of the present invention.

[0071] Reference numerals: line power generation module 100, DC power supply 110, single-chip microcomputer 120, three-phase voltage inverter 130, three-phase current inverter 140, voltage amplitude adjustment knob 150, current amplitude adjustment knob 160, frequency adjustment knob 170; meter module 200, three-phase AC voltmeter 210, three-phase AC ammeter 220; line working environment simulation module 300; switch body module 400; port module 500; operation panel 600, panel anti-collision bar 610, foot pad 620; housing 700, front panel 710, corner guard 711, side panel 720, rear panel 730, bottom panel 740; operation panel PCB 810, inverter control board 820, main control board 830, three-phase transformer 831. Detailed implementation manners

[0072] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as a limitation of the present invention.

[0073] In the description of the present invention, it should be understood that with respect to the orientation description, such as the upper, lower, front, rear, left, right, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0074] In the description of the present invention, the meaning of several is more than one, and the meaning of multiple is more than two. Greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If the first and second are described only for the purpose of distinguishing technical features, they should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or the sequence of the indicated technical features.

[0075] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0076] In the description of the present invention, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0077] The following combines the attached Figures 1 - 5 to describe in detail the distribution network secondary terminal test circuit and equipment of the embodiments of the present invention.

[0078] Refer to Figure 1 and Figure 2 The present invention provides a distribution network secondary terminal test circuit, including:

[0079] A line power generation module 100 for providing three-phase power;

[0080] A line working environment simulation module 300, electrically connected to the line power generation module 100, for simulating several input scenarios of three-phase power, and also for implementing the function of inputting or withdrawing zero-sequence voltage and inputting or withdrawing zero-sequence current;

[0081] A switch body module 400, electrically connected to the line working environment simulation module 300 and also electrically connected to the line power generation module 100, for simulating the working state and fault conditions of the circuit breaker;

[0082] A port module 500, electrically connected to the switch body module 400, and also for electrically connecting to the distribution network secondary terminal.

[0083] Specifically, in this embodiment, as Figure 1 shown, the distribution network secondary terminal equipment test circuit includes a line power generation module 100, a meter module 200, a line working environment simulation module 300, a switch body module 400, and a connection port module 500 between the switch body and the intelligent power distribution terminal.

[0084] The line power generation module 100 mainly includes: a DC power supply 110, two DC / AC modules (inverters) for generating three-phase AC power (including a voltage three-phase inverter 130 and a current three-phase inverter 140), and a voltage amplitude and frequency adjustment part (including a voltage amplitude adjustment knob 150, a current amplitude adjustment knob 160, and a frequency adjustment knob 170).

[0085] The meter module 200 includes a three-phase AC voltmeter 210 and a three-phase AC ammeter 220.

[0086] The line working environment simulation module 300 is mainly used to implement the following functions: realizing the scenarios where the power input end has power on the incoming line side, the outgoing line side, or both sides, and implementing zero-voltage switching and zero-current switching.

[0087] The switch body module 400 is mainly used to implement the following functions: point-moving switch opening and closing control, remote / local switching, local opening and closing buttons, intuitive display of switch status and electrical signal indication, implementation and setting of energy storage time, and fault simulation of the switch.

[0088] The approximate electrical connection relationships among the above-mentioned various modules or components are as Figure 2 shown.

[0089] More specifically, the DC power supply 110 is used to supply power to the entire test platform, such as the DC bus power supply of the inverter and the internal control signal power supply, and a step-down DC / DC power supply chip is used to generate a 5V power supply and a 12V power supply respectively, which are used as the working power supplies for components such as the internal single-chip microcomputer, logic chip, and signal relay.

[0090] Two DC / AC modules (including a voltage three-phase inverter 130 and a current three-phase inverter 140) are respectively used to generate two groups of three-phase three-wire UVW signals with the same phase, which are respectively input into two independent SD-type transformers, and after △-Y transformation, three-phase four-wire AC voltages of ABCN are output. One path is a power supply boosted to a maximum effective value of AC120V, which is used to simulate the output of a voltage transformer in a real scenario; the other path is to generate a power supply with a maximum effective value of AC6V, and a small-value high-power resistor is respectively connected in series to form a current, which is used to simulate the output of a current transformer in a real scenario.

[0091] The voltage amplitude and frequency adjustment part (including a voltage amplitude adjustment knob 150, a current amplitude adjustment knob 160, and a frequency adjustment knob 170) belongs to the extended part of the two DC / AC modules, and the requirements for amplitude and frequency can be input to the single-chip microcomputer by means of a mechanical knob or a liquid crystal plus operation panel, and the single-chip microcomputer 120 performs an adjustment action to change the output voltage amplitude.

[0092] The meter module 200 includes a three-phase AC voltage meter 210 and a three-phase AC ammeter 220, which are used to indicate the effective voltage value and effective current value of the analog voltage transformer and current transformer output by the voltage three-phase inverter 130 and the current three-phase inverter 140.

[0093] When the line working environment simulation module 300 realizes the scenarios where the power input end has power on the incoming line side, the outgoing line side, or both sides, such as Figure 2As shown, the normally open contacts at both ends of the relays RLY3 and RLY4 representing the switch body are respectively connected to the power bus through the normally open contacts of the relays RLY1 and RLY2, and finally the voltage sampling is output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal. The self-locking buttons SB1 and SB2 respectively control the monostable relays RLY1 and RLY2. When the button SB1 is pressed, RLY1 is energized, indicating that there is power on the incoming side of the switch body; when the button SB2 is pressed, RLY2 is energized, indicating that there is power on the outgoing side of the switch body; when the buttons SB1 and SB2 are pressed simultaneously, RLY1 and RLY2 are energized simultaneously, indicating that there is power on both sides of the switch body.

[0094] When the line working environment simulation module 300 realizes zero-voltage switching on and off and zero-current switching on and off, since the phases of the zero-sequence voltage and zero-sequence current are the same as those of phase B, the present invention uses two self-locking switches SB7 and SB8 respectively connected to phase B to achieve this. When it is necessary to switch on the zero-sequence voltage, when the self-locking switch SB7 is pressed, the phase B voltage of the voltage three-phase inverter 130 is connected to the bus through SB7, and is connected to RLY4 representing the switch body through the normally open contacts of RLY1 and RLY2; when it is necessary to switch on the zero-sequence current, when the self-locking switch SB8 is pressed, the phase B current of the current three-phase inverter 140 is connected to the resistor R1 through SB8 and the normally open contact of RLY3, thereby forming a current. Finally, similar to the in-phase voltage and current, the zero-sequence voltage and current sampling are also output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal.

[0095] When the switch body module 400 realizes the point-by-point switch opening and closing control, as described above, RLY3 and RLY4 simulate the contacts of the circuit breaker. The working mode of the real circuit breaker is to give a 30 - 100 ms electrical signal to the opening coil or closing coil, and the circuit breaker releases the spring energy storage inside to perform opening and closing. In this platform, a double-coil magnetic latching relay RLY5 is used to achieve this. After the coil of RLY5 or the reset coil action is completed, the open / closed state of the contacts is maintained by the permanent magnet inside the relay, and further a clear opening and closing signal is given to RLY3 and RLY4. It perfectly simulates the working mode of the real circuit breaker.

[0096] When the switch body module 400 implements the functions of in-situ opening / closing buttons, remote / local switching, intuitive display of the in-situ opening / closing button switch status, and electrical signal indication, it is implemented using an in-situ logic module. A tripping button is arranged on the test platform to control the tripping / closing operation of the circuit breaker body part of the test platform. A remote / local button is arranged on the test platform. When it is placed in the remote position, the in-situ opening / closing buttons are invalid, and only remote control (which can be an intelligent power distribution terminal) can be used; when placed in the local position, the remote control is invalid, and only the in-situ opening / closing buttons can be used for operation. Two LED indicators are arranged on the test platform to indicate the working status of the circuit breaker. A red LED is used to represent that the simulated circuit breaker is in the closed position, and a green LED is used to represent that the simulated circuit breaker is in the open position. All the buttons on the test platform use indicators to indicate the working status of the buttons.

[0097] When the switch body module 400 realizes and sets the energy storage time, since the real circuit breaker will have an energy storage motor drive the energy storage spring to store energy after tripping, and the circuit breaker cannot perform actions when the energy storage is not completed. The present invention simulates this characteristic using an integrated circuit, and uses a red indicator light to display the energy storage status (defined as the non-energy-stored light). When the switch trips, the non-energy-stored platform starts timing, the non-energy-stored light lights up, and the operation circuit is locked before the timing is completed, and no operation can be performed; after the timing is completed, the non-energy-stored light goes out and operations can be performed. The non-energy-stored time can be set. A knob, that is, a non-energy-stored time adjustment knob, is arranged on the platform, and the energy storage time can be set by turning the knob.

[0098] When the switch body module 400 simulates the switch faults, it mainly simulates "current in the tripped position" in line faults and "switch refusal to operate" in switch body faults;

[0099] The self-locking switch SB4 is used to implement the function of "current in the tripped position", that is, when SB4 is turned on, RLY3 is driven by SB4, so that the current sampling signal is output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal, thereby simulating the fault phenomenon of "current in the tripped position";

[0100] The normally closed button SB3 for switch refusal to operate is used to implement the function of "switch refusal to operate". SB3 is normally closed. When SB3 is turned off, the power supply of RLY5 is turned off. Then, no matter what signal is given externally, RLY5 will not operate, thereby simulating the fault phenomenon of "switch refusal to operate".

[0101] By setting up the line power generation module 100, it can convert low-voltage direct current into three-phase four-wire alternating current simulating the actual working conditions of the analog distribution network terminal, and can provide power for devices such as the tested distribution terminal without the need for an additional power source. By setting up the line working environment simulation module 300 and the switch body module 400 electrically connected thereto, it can comprehensively simulate the actual working conditions of the primary switch. It is equivalent to moving the on-site environment to the laboratory. The two inverter modules inside simulate the power output of the low-voltage side of the substation and can simulate the situation of power coming from both sides of the primary switch. By setting up the port module 500, the connection port of the present invention with the distribution terminal covers all the functions of the real primary switch. For the distribution terminal, the present invention is a real circuit breaker. The interaction between the present invention and the operator not only includes the operation of the analog circuit breaker but also the operation of the line working conditions. By integrating all the modules required for testing into a circuit board and placing them in the secondary terminal equipment of the distribution network, the portability of the present invention can be improved and the cost can be reduced. The present invention has the characteristics of high integration and light weight, low cost, comprehensive functions for testing the characteristics of the secondary terminal equipment of the distribution network, and strong applicability, which can greatly improve the popularization rate.

[0102] Referring to Figure 1 and Figure 2 , further, in some embodiments of the present invention, the line power generation module includes:

[0103] A DC power supply 110 for providing line power and control power;

[0104] A single-chip microcomputer 120, electrically connected to the DC power supply, for receiving and adjusting the line power;

[0105] A voltage three-phase inverter 130, the input end of the voltage three-phase inverter is electrically connected to the single-chip microcomputer 120, and the output end is electrically connected to the line working environment simulation module, for converting the line power into three-phase AC voltage and outputting it to the line working environment simulation module;

[0106] A current three-phase inverter 140, the input end of the current three-phase inverter 140 is electrically connected to the single-chip microcomputer, and the output end is electrically connected to the switch body module, for converting the line power into three-phase AC current and outputting it to the switch body module;

[0107] A voltage amplitude adjustment knob 150, electrically connected to the single-chip microcomputer 120;

[0108] A current amplitude adjustment knob 160, electrically connected to the single-chip microcomputer 120;

[0109] A frequency adjustment knob 170, electrically connected to the single-chip microcomputer 120.

[0110] Specifically, in this embodiment, the DC power supply 110 is used to supply power to the entire test platform, such as the DC bus power supply of the inverter and the internal control signal power supply. A buck DC / DC power supply chip is used to generate a 5V power supply and a 12V power supply respectively, which are used as the working power supplies for components such as the internal single-chip microcomputer, logic chip, and signal relay.

[0111] Two DC / AC modules (including the voltage three-phase inverter 130 and the current three-phase inverter 140) are respectively used to generate two groups of three-phase three-wire UVW signals with the same phase, which are respectively input into two independent SD-type transformers. After the △-Y transformation, three-phase four-wire AC voltages of ABCN are output. One path is a power supply boosted to a maximum effective value of AC120V, which is used to simulate the output of a voltage transformer in a real scenario; the other path is a power supply with a maximum effective value of AC6V generated by voltage reduction. A small-value and high-power resistor is respectively connected in series to form a current, which is used to simulate the output of a current transformer in a real scenario.

[0112] The voltage amplitude and frequency adjustment part (including the voltage amplitude adjustment knob 150, the current amplitude adjustment knob 160, and the frequency adjustment knob 170) belongs to the extended part of the two DC / AC modules. The requirements for amplitude and frequency can be input to the single-chip microcomputer by means of a mechanical knob or a liquid crystal plus operation panel. The single-chip microcomputer 120 performs adjustment actions to change the output voltage amplitude.

[0113] By setting the line power generation module 100, low-voltage direct current can be converted into three-phase four-wire alternating current simulating the actual working conditions of the distribution network terminal, which can supply power to devices such as the tested distribution terminal and does not require an additional power supply.

[0114] Refer to Figure 1 and Figure 2 , further, in some embodiments of the present invention, the line working environment simulation module 300 includes:

[0115] The first relay RLY1, the input end of the first relay RLY1 is electrically connected to the output end of the voltage three-phase inverter 130, and the output end of the first relay RLY1 is electrically connected to the input end of the switch body module 400. The first relay RLY1 is used to simulate the voltage input scenario on the incoming line side of the circuit breaker;

[0116] The first self-locking button SB1, the first self-locking button SB1 is electrically connected to the control end of the first relay RLY1;

[0117] The second relay RLY2, the input end of the second relay RLY2 is electrically connected to the output end of the voltage three-phase inverter 130, and the output end of the second relay RLY2 is electrically connected to the output end of the switch body module 400. The second relay RLY2 is used to simulate the voltage input scenario on the outgoing line side of the circuit breaker;

[0118] The second self-locking button SB2, and the second self-locking button SB2 is electrically connected to the control terminal of the second relay RLY2.

[0119] Specifically, in this embodiment, when the line working environment simulation module 300 realizes the scenario where the power input end is the incoming line side or the outgoing line side or both sides are powered, as Figure 2 shown, the normally open contacts of the relays RLY3 and RLY4 representing the switch body are respectively connected to the power bus through the normally open contacts of the relays RLY1 and RLY2, and finally the voltage sampling is output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal. The self-locking buttons SB1 and SB2 respectively control the monostable relays RLY1 and RLY2. When the button SB1 is pressed, RLY1 is energized, indicating that the incoming line side of the switch body is powered; when the button SB2 is pressed, RLY2 is energized, indicating that the outgoing line side of the switch body is powered; when the buttons SB1 and SB2 are pressed simultaneously, RLY1 and RLY2 are energized simultaneously, indicating that both sides of the switch body are powered.

[0120] Referring to Figure 2 , further, in some embodiments of the present invention, the line working environment simulation module 300 further includes:

[0121] The zero-voltage input / output self-locking switch SB7, one end of the zero-voltage input / output self-locking switch SB7 is electrically connected to one phase of the output end of the voltage three-phase inverter 130, and the other end of the zero-voltage input / output self-locking switch is electrically connected to the input ends of the first relay RLY1 and the second relay RLY2;

[0122] The zero-current input / output self-locking switch SB8, one end of the zero-current input / output self-locking switch SB8 is electrically connected to one phase of the output end of the current three-phase inverter 140, and the other end of the zero-current input / output self-locking switch is electrically connected to the input end of the third relay RLY3.

[0123] Specifically, in this embodiment, when the line working environment simulation module 300 realizes zero-voltage input / output and zero-current input / output, since the phase of the zero-sequence voltage and the zero-sequence current is the same as that of the B phase, the present invention uses two self-locking switches SB7 and SB8 to be respectively connected to the B phase to achieve this. When it is necessary to input the zero-sequence voltage, when the self-locking switch SB7 is pressed, the B-phase voltage of the voltage three-phase inverter 130 is connected to the bus through SB7 and connected to RLY4 representing the switch body through the normally open contacts of RLY1 and RLY2; when it is necessary to input the zero-sequence current, when the self-locking switch SB8 is pressed, the B-phase current of the current three-phase inverter 140 is connected to the resistor R1 through SB8 and the normally open contact of RLY3, thereby forming a current. Finally, like the in-phase voltage and current, the zero-sequence voltage and current sampling are also output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal.

[0124] Reference Figure 2 Furthermore, in some embodiments of the present invention, the switch body module 400 includes:

[0125] A third relay RLY3 for simulating a three-phase current circuit breaker. The input end of the third relay RLY3 is electrically connected to the current three-phase inverter 140, and the output end of the third relay RLY3 is electrically connected to the port module 500;

[0126] A fourth relay RLY4 for simulating a three-phase voltage circuit breaker. The input end of the fourth relay RLY4 is electrically connected to the output end of the first relay RLY1. The input end of the fourth relay RLY4 is also electrically connected to the port module 500. The output end of the fourth relay RLY4 is electrically connected to the output end of the second relay RLY2, and the output end of the fourth relay RLY4 is also electrically connected to the port module 500;

[0127] A fifth relay RLY5. The input end of the fifth relay RLY5 is electrically connected to the control power supply. The output end of the fifth relay RLY5 is electrically connected to the control ends of the third relay RLY3 and the fourth relay RLY4. The fifth relay RLY5 adopts a double-coil magnetic latching relay.

[0128] Specifically, in this embodiment, when the switch body module 400 realizes the point-by-point switch closing and opening control, as described above, RLY3 and RLY4 simulate the contacts of the circuit breaker. The working mode of a real circuit breaker is to give a 30 - 100 ms electrical signal to the opening coil or closing coil, and the circuit breaker releases the internal spring energy storage to perform closing and opening. In this platform, a double-coil magnetic latching relay RLY5 is used to achieve this. When the coil action or the reset coil action of RLY5 is completed, the open / closed state of the contacts is maintained by the permanent magnet inside the relay, and further, a clear closing and opening signal is given to RLY3 and RLY4. It perfectly simulates the working mode of a real circuit breaker.

[0129] Reference Figure 2 Furthermore, in some embodiments of the present invention, the switch body module 400 further includes:

[0130] A local logic module. The output end of the local logic module is electrically connected to the control end of the fifth relay RLY5;

[0131] A local switch closing button SB5, one end of which is electrically connected to the control power supply and the other end of which is electrically connected to the input end of the local logic module;

[0132] A local switch tripping button SB6, one end of which is electrically connected to the control power supply and the other end of which is electrically connected to the input end of the local logic module;

[0133] Remote / local switching button, one end electrically connected to the control power supply, and the other end electrically connected to the input terminal of the local logic module;

[0134] Jumping position with current button SB4, one end electrically connected to the control power supply, and the other end electrically connected to the control terminal of the third relay RLY3;

[0135] Switch refusal to operate normally closed button SB3, one end electrically connected to the control power supply, and the other end electrically connected to the input terminal of the local logic module;

[0136] Switch uncharged time adjustment knob, electrically connected to the input terminal of the local logic module;

[0137] Switch uncharged indicator light La3, electrically connected to the output terminal of the local logic module.

[0138] Specifically, in this embodiment, when the switch body module 400 realizes the functions of local opening / closing buttons, remote / local switching, intuitive display of the switch state of the local opening / closing buttons, and electrical signal indication, it is implemented by the local logic module. A tripping button is arranged on the test platform to control the tripping / closing action of the circuit breaker body part of the test platform. A remote / local button is arranged on the test platform. When placed in the remote position, the local opening / closing buttons are invalid, and only remote control (which can be an intelligent power distribution terminal) can be used; when placed in the local position, the remote control is invalid, and only the local opening / closing buttons can be used for operation. Two LED indicator lights are arranged on the test platform to indicate the working state of the circuit breaker. A red LED is used to represent that the simulated circuit breaker is in the closed position, and a green LED is used to represent that the simulated circuit breaker is in the open position. All the buttons on the test platform use indicator lights to indicate the working state of the buttons.

[0139] When the switch body module 400 realizes the energy storage time and sets the energy storage time, since the real circuit breaker will have an energy storage motor driving the energy storage spring to store energy after tripping, and the circuit breaker cannot perform actions when the energy storage is not completed. The present invention simulates this characteristic using an integrated circuit, and uses a red indicator light La3 to display the energy storage state (defined as the uncharged light). After the switch trips, the uncharged platform starts timing, and the uncharged light La3 lights up. The operation circuit is locked before the timing is completed and no operation can be performed; after the timing is completed, the uncharged light La3 goes out and operations can be performed. The uncharged time can be set. A knob, namely the uncharged time adjustment knob, is arranged on the platform, and the energy storage time can be set by turning the knob.

[0140] When the switch body module 400 simulates the switch faults, it mainly simulates "jumping position with current" in line faults and "switch refusal to operate" in switch body faults;

[0141] Use the self-locking switch SB4 to implement the function of "current flowing in the tripped position". That is, when SB4 is turned on, RLY3 is driven by SB4, so that the current sampling signal is output to the outside of the test platform through the banana socket and connected to the intelligent power distribution terminal, thereby simulating the fault phenomenon of "current flowing in the tripped position".

[0142] Use the normally closed button SB3 for switch refusal to operate to implement the function of "switch refusal to operate". SB3 is normally closed. When SB3 is turned off, the power supply of RLY5 is turned off. Then, regardless of what signal is given externally, RLY5 will not operate, thereby simulating the fault phenomenon of "switch refusal to operate".

[0143] Refer to Figure 2 , further, in some embodiments of the present invention, the port module 500 includes:

[0144] The incoming line terminal voltage sampling socket (U01~Un1), which is electrically connected to the input end of the fourth relay RLY4 and is also used to be electrically connected to the secondary terminal of the distribution network;

[0145] The outgoing line terminal voltage sampling socket (U02~Un2), which is electrically connected to the output end of the fourth relay RLY4 and is also used to be electrically connected to the secondary terminal of the distribution network;

[0146] The current sampling socket (I0~In), which is electrically connected to the output end of the third relay RLY3 and is also used to be electrically connected to the secondary terminal of the distribution network;

[0147] The switch tripped position remote signaling terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network;

[0148] The switch closed position remote signaling terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network;

[0149] The switch remote closing terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network;

[0150] The switch remote tripping terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network;

[0151] The switch uncharged position terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network.

[0152] Refer to Figure 1 and Figure 2 , further, in some embodiments of the present invention, a meter module 200 is also provided. The meter module 200 includes:

[0153] The three-phase AC voltage meter 210 is disposed between the voltage three-phase inverter 130 and the line working environment simulation module 300;

[0154] The three-phase AC ammeter 220 is disposed between the current three-phase inverter 140 and the switch body module 400.

[0155] The meter module 200 includes a three-phase AC voltage meter 210 and a three-phase AC ammeter 220, and is used to indicate the effective voltage value and the effective current value of the analog voltage transformer and the current transformer output by the voltage three-phase inverter 130 and the current three-phase inverter 140.

[0156] Refer to Figure 3 、 Figure 4 and Figure 5 ,the present invention also provides a secondary terminal test device for a distribution network, including:

[0157] The housing 700;

[0158] The operation panel 600 is disposed on one side of the housing and is used for electrically connecting with the secondary terminal of the distribution network;

[0159] The circuit board module is disposed in the housing 700 and is electrically connected to the operation panel 600. The circuit board module is provided with the secondary terminal test circuit for the distribution network as described in any one of the above embodiments, and the operation panel is also used to adjust the working state of the circuit board module.

[0160] Specifically, in this embodiment, by integrating all the modules required for testing into a circuit board and placing them in the secondary terminal device of the distribution network, the portability of the present invention is improved and the cost is reduced. The housing 700 is surrounded by the operation panel 600, the front panel 710, two side panels 720, the rear panel 730, and the bottom panel 740 to form a cuboid hollow closed structure. The cavity is used to fixedly place the circuit board module with the secondary terminal test circuit for the distribution network, and the front panel 710 is provided with corner guards 711. The ports and knobs on the operation panel 600 are distributed as Figure 5 shown. The operation panel 600 is fixedly provided with foot pads 620 and panel anti-collision bars 610, so as to prevent accidental touch and misoperation, and at the same time improve the portability of the device. The operation panel is also fixedly provided with a three-phase AC voltage meter 210 and a three-phase AC ammeter 220, which can conveniently observe the effective voltage value and the effective current value of the current bus from the outside.

[0161] Refer to Figure 4 ,furthermore, in some embodiments of the present invention, the circuit board module includes:

[0162] The operation panel PCB 810 is electrically connected to the operation panel 600, and the operation panel PCB 810 is provided with a port module 500;

[0163] The DC power supply 110 and the inverter control board 820 are electrically connected to the operation panel PCB 810, and the DC power supply 110 and the inverter control board 820 are used to form the line power generation module 100;

[0164] The main control board 830 is electrically connected to the DC power supply 110 and the inverter control board 820, and is also electrically connected to the operation panel PCB 810. The main control board 830 is provided with a line working environment simulation module 300 and a switch body module 400.

[0165] Specifically, in this embodiment, the main control board 830 and the three-phase transformer 831 are fixed on the bottom plate 740. The operation panel PCB 810 and the operation panel 600 are fixedly connected by screws. The DC power supply 110 can convert alternating current into direct current energy storage, thus facilitating the charging of the device and improving the applicability of the device. The inverter control board 820 is electrically connected to the main control board 830 through a socket terminal.

[0166] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made without departing from the spirit of the present invention within the knowledge scope of those of ordinary skill in the art. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A secondary terminal test circuit for a distribution network, characterized in that, Comprising: A line power generation module for providing three-phase power; A line working environment simulation module electrically connected to the line power generation module, for simulating several input scenarios of the three-phase power, and also for implementing the functions of inputting or withdrawing zero-sequence voltage and inputting or withdrawing zero-sequence current; A switch body module electrically connected to the line working environment simulation module and also electrically connected to the line power generation module, for simulating the working state and fault conditions of a circuit breaker; A port module electrically connected to the switch body module and also for electrically connecting to a secondary terminal of a distribution network; The line power generation module includes: A DC power supply for providing line power and control power; A single-chip microcomputer electrically connected to the DC power supply, for receiving and adjusting the line power; A voltage three-phase inverter, the input end of which is electrically connected to the single-chip microcomputer, and the output end of which is electrically connected to the line working environment simulation module, for converting the line power into three-phase AC voltage and outputting it to the line working environment simulation module; A current three-phase inverter, the input end of which is electrically connected to the single-chip microcomputer, and the output end of which is electrically connected to the switch body module, for converting the line power into three-phase AC current and outputting it to the switch body module; A voltage amplitude adjustment knob electrically connected to the single-chip microcomputer; A current amplitude adjustment knob electrically connected to the single-chip microcomputer; A frequency adjustment knob electrically connected to the single-chip microcomputer; The line working environment simulation module includes: A first relay, the input end of which is electrically connected to the output end of the voltage three-phase inverter, and the output end of which is electrically connected to the input end of the switch body module, and the first relay is used for simulating the voltage input scenario on the incoming line side of the circuit breaker; A first self-locking button electrically connected to the control end of the first relay; A second relay, the input end of which is electrically connected to the output end of the voltage three-phase inverter, and the output end of which is electrically connected to the output end of the switch body module, and the second relay is used for simulating the voltage input scenario on the outgoing line side of the circuit breaker; A second self-locking button electrically connected to the control end of the second relay; The line working environment simulation module further includes: A zero-voltage input / output self-locking switch, one end of which is electrically connected to one phase of the output end of the voltage three-phase inverter, and the other end of which is electrically connected to the input ends of the first relay and the second relay; A zero-current input / output self-locking switch, one end of which is electrically connected to one phase of the output end of the current three-phase inverter, and the other end of which is electrically connected to the switch body module.

2. The secondary terminal test circuit of the distribution network according to claim 1, wherein The switch body module includes: A third relay for simulating a three-phase current circuit breaker, the input end of which is electrically connected to the current three-phase inverter, and the output end of which is electrically connected to the port module; The fourth relay is used to simulate a three-phase voltage circuit breaker. The input end of the fourth relay is electrically connected to the output end of the first relay. The input end of the fourth relay is also electrically connected to the port module. The output end of the fourth relay is electrically connected to the output end of the second relay. The output end of the fourth relay is also electrically connected to the port module; The fifth relay. The input end of the fifth relay is electrically connected to the control power supply. The output end of the fifth relay is electrically connected to the control end of the third relay and the control end of the fourth relay. The fifth relay adopts a double-coil magnetic latching relay.

3. The secondary terminal test circuit of the distribution network according to claim 2, characterized in that, The switch body module further includes: The local logic module. The output end of the local logic module is electrically connected to the control end of the fifth relay; The local switch closing button, with one end electrically connected to the control power supply and the other end electrically connected to the input end of the local logic module; The local switch tripping button, with one end electrically connected to the control power supply and the other end electrically connected to the input end of the local logic module; The remote / local switching button, with one end electrically connected to the control power supply and the other end electrically connected to the input end of the local logic module; The tripping position with current button, with one end electrically connected to the control power supply and the other end electrically connected to the control end of the third relay; The switch refusal to operate normally closed button, with one end electrically connected to the control power supply and the other end electrically connected to the input end of the local logic module; The switch unenergized time adjustment knob, which is electrically connected to the input end of the local logic module; The switch unenergized indicator light, which is electrically connected to the output end of the local logic module.

4. The secondary terminal test circuit of the distribution network according to claim 3, wherein, The port module includes: The incoming line voltage sampling socket, which is electrically connected to the input end of the fourth relay and is also used to be electrically connected to the secondary terminal of the distribution network; The outgoing line voltage sampling socket, which is electrically connected to the output end of the fourth relay and is also used to be electrically connected to the secondary terminal of the distribution network; The current sampling socket, which is electrically connected to the output end of the third relay and is also used to be electrically connected to the secondary terminal of the distribution network; The switch tripping position remote signaling terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network; The switch closing position remote signaling terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network; The switch remote closing terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network; The switch remote tripping terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network; The switch unenergized position terminal, which is electrically connected to the output end of the local logic module and is also used to be electrically connected to the secondary terminal of the distribution network.

5. The secondary terminal test circuit of the distribution network according to claim 1, characterized in that, A meter module is also provided. The meter module includes: A three-phase AC voltage meter, which is arranged between the voltage three-phase inverter and the line working environment simulation module; A three-phase AC ammeter, which is arranged between the current three-phase inverter and the switch body module.

6. A secondary terminal test device for a distribution network, characterized in that, It includes: A housing; An operation panel, which is arranged on one side of the housing and is used for electrically connecting with the secondary terminal of the distribution network; A circuit board module, which is arranged in the housing and is electrically connected with the operation panel. The circuit board module is provided with the test circuit for the secondary terminal of the distribution network as described in any one of claims 1-5, and the operation panel is also used for adjusting the working state of the circuit board module.

7. The secondary terminal test equipment for a distribution network according to claim 6, characterized in that, The circuit board module includes: An operation panel PCB, which is electrically connected with the operation panel and is provided with a port module; A DC power supply and an inverter control board, which are electrically connected with the operation panel PCB and are used for forming a line power generation module; A main control board, which is electrically connected with the DC power supply and the inverter control board and is also electrically connected with the operation panel PCB. The main control board is provided with a line working environment simulation module and a switch body module.

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