Alternating current and direct current integrated multifunctional test device

Abstract

The invention discloses an alternating current and direct current integrated multifunctional test device, which belongs to the technical field of alternating current and direct current voltage tests and comprises a box body and an input module, the alternating current test module is arranged in the box body and is used for testing a switching function, an open-phase automatic input function and an under-voltage tripping function of the automatic transfer switch device; the impedance test module is arranged in the box body and is used for carrying out a single-pole grounding fault test and a two-pole grounding fault test on the direct current system; and the direct current output module is arranged in the box body and is used for testing the alternating current into the direct current system. The device realizes multiple functions, has multiple test items, can be widely applied to substation transformation and capital construction acceptance sites, and improves the test efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of AC and DC voltage testing, and more specifically, relates to an AC and DC integrated multifunctional testing device. Background Art

[0002] Substations require access to a test power supply during electrical testing, overhaul, and maintenance. These substations typically have very few (or even no) outdoor power connectors. Therefore, a large number of power boxes are required for series and parallel integration to meet the power requirements of on-site maintenance. For remote sites, the external power supply is far away, and a power box with a 50m cable length still cannot meet on-site needs, which is very inconvenient. When the entire station is shut down for overhaul, a self-provided generator is required. However, the large size and weight of the generator make it inconvenient to transport, and the power quality does not meet the requirements, posing a risk of damage to precision instruments.

[0003] Installing and replacing protective devices in substations is a daunting task, and obtaining DC power on-site is challenging. Traditionally, long temporary wires or cables have been used to connect the test power panel to the protective panel, creating a high risk of electric shock.

[0004] Furthermore, existing power boxes, which power other devices, have specific requirements for voltage, current, and voltage or current. These boxes cannot meet the testing requirements of various devices, significantly limiting their application. Power plugs for protective devices must be replaced frequently, typically every five years. Relay spare parts must also be tested using AC and DC power supplies to ensure they meet field requirements.

[0005] Therefore, it is very necessary to develop an AC / DC integrated multifunctional test device. Summary of the Invention

[0006] In view of the above-mentioned deficiencies or existing technologies, the present invention proposes an AC / DC integrated multifunctional test device, which integrates multiple tests in one body, has a simple structural design, is easy to operate, and improves test efficiency.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] The present invention provides an AC / DC integrated multifunctional test device, comprising:

[0009] Box,

[0010] Input module, used to provide test voltage;

[0011] AC test module, installed in the box, is used to test the switching function, phase loss automatic input function and undervoltage tripping function of the automatic transfer switch (ATS);

[0012] Impedance test module, installed in the box, used for DC system single-pole ground fault test and two-pole ground fault test;

[0013] The DC output module is installed in the box and is used for AC leakage into DC system testing.

[0014] As a further technical solution of the present invention, an operation panel is provided on the box, wherein the operation panel includes:

[0015] AC module operation area, including two three-phase voltage indicating instruments and a time relay control panel;

[0016] The DC module operation area is equipped with a resistance value selection knob and a grounding mode selection switch;

[0017] The low-voltage output operation area is equipped with a voltage gear selection switch and an output indicator light.

[0018] Furthermore, the input module is a single-phase 220V AC power supply.

[0019] As a further technical solution of the present invention, the AC test module includes:

[0020] A frequency converter connected to the input module and configured to output two independent three-phase AC voltages, wherein a voltage regulator is also provided at the output end of the frequency converter;

[0021] Two three-phase output branches, each three-phase output branch is sequentially provided with a three-phase air switch, a three-phase terminal group and a phase-splitting air switch, the input end of the three-phase air switch is connected to the output end of the inverter, the output end of the three-phase air switch is connected to the phase-splitting air switch, and the output end of the phase-splitting air switch is connected to the three-phase terminal group;

[0022] Time relays, connected in parallel in two three-phase output branches, are configured to monitor the switching time and tripping time of the low-voltage circuit breaker.

[0023] As a further technical solution of the present invention, the DC impedance module includes:

[0024] Resistor unit, configured with resistors of different resistance values;

[0025] A reconfigurable connection circuit is configured to realize series connection, parallel connection or individual output of the resistance units by switching switches;

[0026] Grounding terminal group, including positive grounding terminal, negative grounding terminal and two-pole composite grounding terminal;

[0027] Impedance output terminal group, used to output terminals of different resistance values.

[0028] Furthermore, the resistance unit includes four groups of resistors: 10kΩ, 25kΩ, 30kΩ, and 50kΩ.

[0029] As a further technical solution of the present invention, the DC output module includes:

[0030] A multi-winding transformer, wherein the input side of the multi-winding transformer is connected to the input module, and the output side of the multi-winding transformer is configured with multiple sets of voltage gears;

[0031] a voltage selector switch connected to a tap of a multi-winding transformer;

[0032] The low-voltage output terminal group is connected to the output terminals of each voltage level through a shunt air switch.

[0033] Furthermore, the multiple voltage gears include 10V DC voltage, 12V DC voltage, 24V DC voltage, and 36V DC voltage.

[0034] As a further technical solution of the present invention, it further includes a test protection module, and the test protection module includes:

[0035] Overcurrent protection unit, real-time monitoring of each branch current;

[0036] Insulation monitoring unit, which detects the insulation status of the DC system;

[0037] Fault recording unit, records changes in electrical parameters under abnormal working conditions.

[0038] The beneficial effects of the present invention are:

[0039] 1. The housing of the present invention provides a test platform, and the input module provides operating voltage for the test device. The housing integrates an AC test module, an impedance test module, and a DC output module, forming a single-unit test device. This device can perform ATS switching tests, phase loss automatic switching tests, and undervoltage trip tests for AC systems, as well as single-pole and two-pole grounding tests, and AC-DC crosstalk tests for DC systems. This multifunctional device, capable of a wide range of test items, and economical operation, is easily portable and widely applicable to substation renovations and infrastructure acceptance inspections, demonstrating its high potential for widespread adoption.

[0040] 2. The operation panel is divided into AC module operation area, impedance module operation area and low voltage output operation area according to function. The indicator lights and operation buttons are set to facilitate operation. The test wiring and resistance value can be selected according to different test requirements. The test process is simple and fast, which can improve the test efficiency.

[0041] 3. Output circuit breaker is realized by setting a three-phase air switch. By setting a phase-splitting air switch on each phase of the three-phase output line, it can be used to close the output of any phase for phase loss test. The output voltage can be set as a percentage of the rated value for undervoltage test.

[0042] 4. A time relay is connected in parallel to each three-phase output branch to measure the ATS switching time or circuit breaker tripping time.

[0043] 5. The multi-winding transformer adopts EI type iron core with electrostatic shielding layer to reduce high-frequency interference. The voltage selector switch can adopt rotary band switch and adopt mechanical interlock structure to prevent misoperation.

[0044] 6. The overcurrent protection unit monitors the current of each branch in real time. A self-recovery fuse is configured on each output to prevent short-circuit damage. The test device has a built-in SD card to store test data such as switching time and trip voltage. It supports USB data export to facilitate the generation of test reports. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0046] Figure 1 A structural diagram of an AC / DC integrated multifunctional test device provided in an embodiment of the present invention;

[0047] Figure 2 This is a circuit control diagram of the AC / DC integrated multifunctional test device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0050] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments. It should be noted that the embodiments of the present invention can be applied to any applicable scenario.

[0051] Figure 1 The AC / DC integrated multifunctional test device provided by one embodiment of the present invention includes:

[0052] Box,

[0053] Input module, used to provide test voltage;

[0054] AC test module, installed in the box, is used to test the switching function, phase loss automatic input function and undervoltage tripping function of the automatic transfer switch (ATS);

[0055] Impedance test module, installed in the box, used for DC system single-pole ground fault test and two-pole ground fault test;

[0056] The DC output module is installed in the box and is used for AC leakage into DC system testing.

[0057] In the embodiment of the present invention, the box serves as a fixed support for the AC / DC integrated multifunctional test device, providing a test platform for the test. The input module provides working voltage for the test device. An external 220V power supply can be used, and a plug is set on the external power supply for easy connection. A mobile power supply can also be configured as needed, which is subject to specific on-site requirements. The present invention does not limit the specific setting of the power supply, as long as it can provide working power for the test device.

[0058] The test device integrates an AC test module, an impedance test module, and a DC output module within a box. It can perform ATS switching tests, phase loss automatic switching tests, and undervoltage trip tests on AC systems, as well as single-pole and two-pole grounding tests, and AC-DC crosstalk tests on DC systems. This multifunctional device, with its wide range of test items and high cost-effectiveness, is easy to carry and can be widely used in substation renovations and infrastructure acceptance inspections, with high promotion value.

[0059] The box body provided in the embodiment of the present invention is provided with an operation panel, wherein the operation panel includes:

[0060] AC module operation area, including two three-phase voltage indicating instruments and a time relay control panel;

[0061] The impedance module operation area is equipped with a resistance value selection knob and a grounding mode selection switch;

[0062] The low-voltage output operation area is equipped with a voltage gear selection switch and an output indicator light.

[0063] The operation panel is divided into AC module operation area, impedance module operation area and low voltage output operation area according to function. The indicator lights and operation buttons are set to facilitate operation. The test wiring and resistance value can be selected according to different test requirements. The test process is simple and fast, which can improve test efficiency.

[0064] See also Figure 2 In the embodiment of the present invention, the input module is a single-phase 220V AC power supply.

[0065] AC test module, including:

[0066] A frequency converter connected to the input module and configured to output two independent three-phase AC voltages, wherein a voltage regulator is also provided at the output end of the frequency converter;

[0067] Two three-phase output branches, each three-phase output branch is sequentially provided with a three-phase air switch, a three-phase terminal group and a phase-splitting air switch. The input end of the three-phase air switch is connected to the output end of the inverter, the output end of the three-phase air switch is connected to the phase-splitting air switch, and the output end of the phase-splitting air switch is connected to the three-phase terminal group;

[0068] Time relays, connected in parallel in two three-phase output branches, are configured to monitor the switching time and tripping time of the low-voltage circuit breaker.

[0069] The inverter can be Siemens' G120 series, which has a single-phase 220V input and two independently adjustable three-phase 380V outputs. Both outputs can achieve 0-100% voltage adjustment and 45-65Hz frequency adjustment. Output circuit breaker is set by setting a three-phase air switch. By setting a phase-splitting air switch on each phase of the three-phase output line, it can be used to shut off any phase output for phase loss testing. The output voltage can be set as a percentage of the rated value for undervoltage testing. For undervoltage testing, the output voltage can be selected to be 50%-70% of the rated value. The phase-splitting air switch can use a miniature circuit breaker for single-phase output control.

[0070] The time relay can be an Omron H5CX series time relay. Connect a time relay in parallel to each three-phase output branch to measure the ATS switching time or circuit breaker tripping time. For example, the timer starts at the moment of voltage drop and stops when the ATS switching is completed. The time relay uses a dual-channel high-precision time relay with an accuracy of 0.1ms to 10ms, improving timing accuracy.

[0071] For the ATS switching test, the specific test method is: connect the main power input of the ATS device to the first three-phase output of the test device, and the backup power supply to the second three-phase output; set the main power supply to 380V / 50Hz for normal use and the backup power supply to 380V / 50Hz for standby use through the inverter; simulate a main power failure such as a sudden power outage or a voltage drop to 70%, and record the ATS switching time from the occurrence of the failure to the connection of the backup power supply; restore the main power supply, and observe whether the ATS automatically switches back to the main power supply by setting the delayed switching logic.

[0072] For the phase loss automatic switching test, the specific test method is: set the main power supply to lose one phase, such as L1 phase is disconnected, observe whether the ATS detects the phase loss and switches to the backup power supply, and record the phase loss detection time and switching time.

[0073] For the undervoltage tripping test, the specific test method is: set the main power supply voltage to gradually decrease, adjust the output voltage through the voltage regulator, such as from 380V to 300V, 250V, observe whether the undervoltage release is activated, and record the tripping voltage threshold and tripping time.

[0074] In an embodiment of the present invention, the DC impedance module includes:

[0075] Resistor unit, configured with resistors of different resistance values;

[0076] A reconfigurable connection circuit is configured to realize series connection, parallel connection and individual output of the resistance units by switching switches;

[0077] Grounding terminal group, including positive grounding terminal, negative grounding terminal and two-pole composite grounding terminal;

[0078] Impedance output terminal group, used to output terminals of different resistance values.

[0079] In this embodiment of the present invention, the grounding terminal set includes single-pole grounding and bipolar grounding. Single-pole grounding involves connecting only a 10kΩ resistor and connecting either the positive or negative electrode to the ground terminal. Bipolar grounding involves connecting both a 10kΩ resistor and a 25kΩ resistor, with the 10kΩ resistor connected to the positive electrode and the 25kΩ resistor connected to the negative electrode. The grounding terminal set of the present invention uses a copper busbar for connection, ensuring low contact resistance.

[0080] The resistor units include four groups of resistors: 10kΩ, 25kΩ, 30kΩ, and 50kΩ. The resistor units of the reconfigurable connection circuit are manufactured using a non-inductive winding process, with a temperature coefficient of less than 50ppm / °C and a power tolerance of no less than 50W, to prevent inductance from affecting DC grounding tests.

[0081] For a DC single-pole grounding test, connect the positive or negative terminal to a 10kΩ resistor and ground the other end. Monitor the DC system insulation monitoring device for alarms and record the grounding resistance value and alarm time.

[0082] For the DC two-pole grounding test, connect the positive pole to a 10kΩ resistor and the negative pole to a 25kΩ resistor. Observe the DC system for any insulation drop alarms or malfunctions (such as relay tripping).

[0083] In an embodiment of the present invention, the DC output module includes:

[0084] A multi-winding transformer, wherein the input side of the multi-winding transformer is connected to the input module, and the output side of the multi-winding transformer is configured with multiple sets of voltage gears;

[0085] a voltage selector switch connected to a tap of a multi-winding transformer;

[0086] The low-voltage output terminal group is connected to the output terminals of each voltage level through a shunt air switch.

[0087] The multi-winding transformer accepts a 220V AC input and outputs 10V, 12V, 24V, and 36V DC voltages. Multiple voltage ranges are available, including 10V DC, 12V DC, 24V DC, and 36V DC. The multi-winding transformer utilizes an EI-type core with an electrostatic shield to reduce high-frequency interference. The voltage selector switch is a rotary band switch with a mechanical interlock to prevent misoperation.

[0088] The multi-winding transformer adopts an isolation transformer structure, with an electrostatic shielding layer between the primary and secondary windings, and the transformer efficiency is not less than 90%.

[0089] Connect the device under test (e.g., a 24V relay) to the 24V output terminal; observe whether the relay closes normally and measure the actuation voltage and release voltage; simulate voltage fluctuations (e.g., 24V drops to 20V) to test the stability of the device under undervoltage conditions.

[0090] In order to prevent faults such as short circuits, a test protection module is also provided, which includes:

[0091] Overcurrent protection unit monitors the current of each branch in real time; by configuring a self-recovery fuse on each output, it prevents short-circuit damage;

[0092] Insulation monitoring unit, detects the insulation status of the DC system; monitors the leakage situation by setting up residual leakage protector;

[0093] The fault recorder records changes in electrical parameters under abnormal operating conditions. The test device features a built-in SD card for recording test data such as switching time and trip voltage. USB data export is supported for easy test report generation.

[0094] In this embodiment of the present invention, the inverter uses a vector-controlled inverter, with output voltage accuracy controlled within ±1% and a frequency adjustment range of 45-65Hz. The time relay assembly includes a high-precision digital time relay with a measurement range of 0.1ms-10s and a dual-channel time measurement function that simultaneously records switching and tripping times. The low-voltage output module is equipped with a voltage compensation circuit, including an automatic voltage regulator and a transient suppression device, to ensure output voltage fluctuations of less than ±2%.

[0095] Furthermore, although the operations of the method of the present invention are described in a particular order in the accompanying drawings, this does not require or imply that these operations must be performed in this particular order, or that all illustrated operations must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

Claims

1. AC / DC integrated multifunctional test device, characterized in that: include: Box, Input module, used to provide test voltage; AC test module, installed in the box, is used to test the switching function, phase loss automatic input function and undervoltage tripping function of the automatic transfer switch device; Impedance test module, installed in the box, used for DC system single-pole ground fault test and two-pole ground fault test; The DC output module is installed in the box and is used for AC leakage into DC system testing.

2. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: An operation panel is provided on the box, wherein the operation panel includes: AC module operation area, including two three-phase voltage indicating instruments and a time relay control panel; The DC module operation area is equipped with a resistance value selection knob and a grounding mode selection switch; The low-voltage output operation area is equipped with a voltage gear selection switch and an output indicator light.

3. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: The input module is a single-phase 220V AC power supply.

4. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: The AC test module includes: A frequency converter connected to the input module and configured to output two independent three-phase AC voltages, wherein a voltage regulator is also provided at the output end of the frequency converter; Two three-phase output branches, each three-phase output branch is sequentially provided with a three-phase air switch, a three-phase terminal group and a phase-splitting air switch, the input end of the three-phase air switch is connected to the output end of the inverter, the output end of the three-phase air switch is connected to the phase-splitting air switch, and the output end of the phase-splitting air switch is connected to the three-phase terminal group; Time relays, connected in parallel in two three-phase output branches, are configured to monitor the switching time and tripping time of the low-voltage circuit breaker.

5. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: The DC impedance module includes: Resistor unit, configured with resistors of different resistance values; A reconfigurable connection circuit is configured to realize series connection, parallel connection or individual output of the resistance units by switching switches; Grounding terminal group, including positive grounding terminal, negative grounding terminal and two-pole composite grounding terminal; Impedance output terminal group, used to output terminals of different resistance values.

6. The AC / DC integrated multifunctional test device according to claim 5, characterized in that: The resistance unit includes four groups of resistors: 10kΩ, 25kΩ, 30kΩ, and 50kΩ.

7. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: The DC output module includes: A multi-winding transformer, wherein the input side of the multi-winding transformer is connected to the input module, and the output side of the multi-winding transformer is configured with multiple sets of voltage gears; a voltage selector switch connected to a tap of a multi-winding transformer; The low-voltage output terminal group is connected to the output terminals of each voltage level through a shunt air switch.

8. The AC / DC integrated multifunctional test device according to claim 7, characterized in that: The multiple voltage gears include 10V DC voltage, 12V DC voltage, 24V DC voltage, and 36V DC voltage.

9. The AC / DC integrated multifunctional test device according to claim 1, characterized in that: Also included is a test protection module, the test protection module including: Overcurrent protection unit, real-time monitoring of each branch current; Insulation monitoring unit, which detects the insulation status of the DC system; Fault recording unit, records changes in electrical parameters under abnormal working conditions.

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