A full load test device and test method

Abstract

The present invention provides a full-load test device and test method, including: a power supply, a compensation capacitor, a detection device, a shunt reactor, a voltage regulator and an intermediate transformer; the shunt reactor is connected in series with the device under test, and then connected in parallel with the compensation capacitor, and then connected to the power supply through the intermediate transformer and the voltage regulator for adjusting the voltage of the intermediate transformer; the outlet of the device under test is connected to the detection device. The test device provided by the present invention overcomes the problem that the existing detection device cannot reach the rated design capacity during on-site operation, resulting in the inability to detect whether the produced compensation equipment is qualified.

Description

Technical Field

[0001] The invention relates to low voltage management of a distribution network, and in particular to a full-load test device and a test method. Background Art

[0002] In recent years, with the increase in user electricity demand and the diversification of load structure, some 10kV distribution lines have experienced terminal voltage reduction due to geographical location, technical factors and management timeliness, which directly leads to a series of problems such as low power factor of 10kV lines, increased voltage drop, increased power loss, reduced service life of distribution equipment, and increased grid safety risks. It has seriously affected the production and quality of life of users and brought certain negative impacts to enterprises. By using the concentrated capacitance impedance formed by the capacitor bank connected in series on the line to compensate for the distributed inductance impedance on the line, the purpose of increasing the line transmission capacity, improving the distribution voltage quality, and improving the load distribution between the parallel lines can be achieved to reduce the total loss. At present, the distribution network series capacitor compensation device has been widely used in the field of "low voltage" management of the distribution network.

[0003] At present, the number of manufacturers that can design and manufacture distribution network series capacitor compensation devices is gradually increasing, but most manufacturers design and manufacture products based on parallel capacitor products. Due to the fundamental difference between their functions and parallel capacitor products, many manufacturers are able to design products but find it difficult to conduct relevant product tests, especially the full-load test of distribution network series capacitor compensation devices in the factory. Most distribution network series capacitor compensation devices only conduct partial tests, such as insulation tests, withstand voltage tests, no-load tests, etc., and rarely conduct load tests. Even if individual manufacturers can conduct load tests, they can only conduct load tests of about 10% of the product capacity, which leads to some problems such as the inability of some distribution network series capacitor compensation devices to reach the rated design capacity during on-site operation and the unqualified distribution network series capacitor compensation device products.

[0004] Therefore, the full-load test of the distribution network series capacitor compensation device has become a major problem that troubles many distribution network series capacitor compensation device manufacturers, and has also become the last barrier restricting whether the distribution network series capacitor compensation device is truly qualified. Summary of the invention

[0005] In order to solve the problem that a series capacitor compensation device in a distribution network cannot be fully loaded for testing, the present invention provides a full load testing device and a testing method.

[0006] The technical solution provided by the present invention is:

[0007] A full-load test device, the device comprising: a power supply, a compensation capacitor, a detection device, a shunt reactor, a voltage regulator and an intermediate transformer;

[0008] The shunt reactor is connected in series with the device under test and in parallel with the compensation capacitor, and then connected to the power supply through an intermediate transformer and a voltage regulator for adjusting the voltage of the intermediate transformer;

[0009] The outlet of the device under test is connected to the detection device.

[0010] Preferably, the measuring device comprises: a voltage transformer, a voltmeter, a current transformer and an ammeter;

[0011] The voltage transformer and the current transformer are arranged at the outlet side of the device under test;

[0012] The voltage transformer is connected in parallel with a voltmeter;

[0013] The current transformer is connected in series with an ammeter.

[0014] Preferably, the device under test includes: a distribution network series capacitor compensation device.

[0015] Preferably, the compensation capacitor includes: the capacitive reactance value of the compensation capacitor is greater than the equivalent capacitive reactance value after the distribution network series capacitor compensation device is connected in series with the shunt reactor.

[0016] Preferably, the intermediate transformer comprises: the primary voltage rating of the intermediate transformer is equal to the maximum output voltage of the voltage regulator, and the voltage value across the secondary voltage rating shunt reactor is equal to the rated voltage value;

[0017] Preferably, the power supply comprises:

[0018] A three-phase 50 Hz power supply, the rated voltage of which matches the input voltage of the voltage regulator.

[0019] A test method using the full-load test device as described in claims 1 to 6, the method comprising:

[0020] The device under test is connected in series with the shunt reactor and then in parallel with the compensation capacitor, and a detection device is connected at the outlet of the device under test;

[0021] The voltage regulator is adjusted according to preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the distribution network series capacitor compensation device detects that the current reaches the rated current of the device under test, and then the adjustment is stopped to obtain the detection data.

[0022] Preferably, before connecting the device under test to the shunt reactor and the compensation capacitor and connecting the detection device at the outlet of the device under test, the method further includes: selecting a device model in a preset test circuit according to the device under test.

[0023] Preferably, the device model in the preset test circuit is selected according to the capacitor connected in series with the distribution network, including:

[0024] The capacitive reactance value of the compensation capacitor is greater than the equivalent capacitive reactance value of the distribution network series capacitor compensation device connected in series with the shunt reactor;

[0025] The primary voltage rating of the intermediate transformer is equal to the maximum output voltage of the voltage regulator, and the voltage value across the secondary voltage rating shunt reactor is equal to the rated voltage value;

[0026] The power supply is a three-phase 50 Hz power supply, and the rated voltage matches the input voltage of the voltage regulator.

[0027] Preferably, the measuring device comprises: a voltage transformer, a voltmeter, a current transformer and an ammeter;

[0028] The voltage transformer and the current transformer are arranged at the outlet side of the series capacitor of the distribution network;

[0029] The voltage transformer is connected in parallel with a voltmeter;

[0030] The current transformer is connected in series with an ammeter.

[0031] Preferably, the device under test includes: a distribution network series capacitor compensation device.

[0032] A test system for a full-load test device, the system comprising:

[0033] A placement module is provided for connecting the device under test in series with the shunt reactor and then in parallel with the compensation capacitor, and connecting the detection device at the outlet of the device under test;

[0034] The adjustment test module is used to adjust the voltage regulator according to preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the device under test detects that the current reaches the rated current of the device under test and stops adjusting to obtain detection data.

[0035] Preferably, the adjustment test module comprises: an adjustment unit, a detection unit, a judgment unit and a test unit;

[0036] The regulating unit is used to adjust the voltage regulator to change the voltage of the intermediate transformer according to preset data;

[0037] The detection unit is used to detect the current and voltage through the detection device located at the outlet of the device under test;

[0038] The judging unit is used to judge whether the current detected by the detection device at the outlet of the device under test reaches the rated current of the device under test;

[0039] The acquisition unit is used to acquire detection data.

[0040] Preferably, the detection unit includes a current detection subunit and a voltage detection subunit;

[0041] The current detection subunit is used to detect the loop current;

[0042] The voltage detection subunit is used to detect the circuit voltage.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] (1) The present invention provides a full-load test device, which solves the problem of using a voltage regulator and an intermediate transformer to adjust the circuit voltage, and determining whether the device under test is under full-load test by detecting the current by a detection device, thereby overcoming the problem that the existing detection device cannot reach the rated design capacity during on-site operation, resulting in the inability to detect whether the produced compensation equipment is qualified;

[0045] (2) The technical solution provided by the present invention adopts a test circuit with a shunt reactor, and the test transformer is compensated by the capacitive reactive power of the capacitor bank, so that the distribution network series capacitor is tested at full load;

[0046] (3) The technical solution provided by the present invention can greatly improve the output capacity of the distribution network series capacitor compensation device when the transformer capacity is insufficient, making it close to the rated load without configuring a large-capacity transformer, which can greatly save the production cost and ensure that the distribution network series capacitor compensation device meets the design requirements before leaving the factory and can operate safely and reliably after arriving at the site;

[0047] (4) The technical solution provided by the present invention adopts a method of optimizing parameters to design a slow voltage increase, thereby avoiding the impact and inrush current problems caused by the direct input of the capacitor bank, and eliminating the switching switch and series reactor of the compensation capacitor;

[0048] (5) The technical solution provided by the present invention adopts the method that the inductive reactive power of the equivalent load branch is slightly larger than the capacitive reactive power of the compensation capacitor at low voltage, and then the voltage is increased, so that the resonance point is avoided at low voltage and small capacity, thereby protecting the test equipment and avoiding the adverse consequences of power outage of the entire plant caused by resonance. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a schematic diagram of a full-load test circuit of a distribution network series capacitor compensation device of the present invention;

[0050] Figure 2 This is a full-load test flow chart of the distribution network series capacitor compensation device of the present invention;

[0051] Among them, 1 is the device under test, 2 is the shunt reactor, 3 is the compensation capacitor, 4 is the intermediate transformer, 5 is the voltage regulator, 6 is the power supply, 7 is the voltage transformer, 8 is the voltmeter, 9 is the current transformer, and 10 is the ammeter. DETAILED DESCRIPTION

[0052] In order to better understand the present invention, the content of the present invention is further described below in conjunction with the accompanying drawings and examples.

[0053] like Figure 1 As shown, the present invention provides a full-load test device, which includes: a power supply, a compensation capacitor, a detection device, a shunt reactor, a voltage regulator and an intermediate transformer;

[0054] The shunt reactor is connected in series with the device under test and in parallel with the compensation capacitor, and then connected to the power supply through an intermediate transformer and a voltage regulator for adjusting the voltage of the intermediate transformer;

[0055] The outlet of the device under test is connected to the detection device.

[0056] The measuring device includes: voltage transformer, voltmeter, current transformer and ammeter;

[0057] The voltage transformer and the current transformer are arranged on the outlet side of the device under test;

[0058] Voltage transformer in parallel with voltmeter;

[0059] Current transformer connected in series with ammeter.

[0060] The devices under test include: distribution network series capacitor compensation device.

[0061] The compensation capacitor includes: the capacitive reactance value of the compensation capacitor is greater than the equivalent capacitive reactance value after the distribution network series capacitor compensation device is connected in series with the shunt reactor.

[0062] The intermediate transformer includes: the primary voltage rating of the intermediate transformer is equal to the maximum output voltage of the voltage regulator, and the voltage value across the secondary voltage rating shunt reactor is equal to the rated voltage value;

[0063] The power supply adopts a three-phase 50Hz power supply, and the rated voltage of the power supply matches the input voltage of the voltage regulator.

[0064] The test method using the above full load test device, such as Figure 2 As shown, the device under test is connected in series with the shunt reactor and then connected in parallel with the compensation capacitor, and a detection device is connected at the outlet of the device under test;

[0065] The voltage regulator is adjusted according to preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the distribution network series capacitor compensation device detects that the current reaches the rated current of the device under test, and then the adjustment is stopped to obtain the detection data.

[0066] After the device under test is connected in series with the shunt reactor and then connected to the compensation capacitor, and before the detection device is connected at the outlet of the device under test, the following also includes: selecting the equipment model in the preset test circuit according to the capacitor in series with the distribution network, including:

[0067] The capacity of the shunt reactor 2 should be slightly greater than or equal to the rated current of the distribution network series capacitor compensation device 1 to ensure that the shunt reactor can operate safely and reliably under full load conditions and that the temperature rise is within the design range.

[0068] The capacitive reactance value of the compensation capacitor 3 should be slightly larger than the equivalent capacitive reactance value of the distribution network series capacitor compensation device 1 and the shunt reactor 2 connected in series.

[0069] The primary voltage rating of the intermediate transformer 4 should be equal to the maximum output voltage of the voltage regulator 5, and the secondary voltage rating should ensure that the voltage value at the two ends of the shunt reactor can reach the rated voltage value, which needs to be determined by calculation.

[0070] The rated voltage of the voltage regulator 5 is equal to the maximum value of the test power supply, and its voltage regulation range should be 0 to 100%.

[0071] The power supply 6 uses a three-phase 50Hz power supply, and the rated voltage matches the input voltage of the voltage regulator.

[0072] The measuring device includes a transformer and a measuring instrument. The voltage transformer 7 and the current transformer 9 are voltage and current transformers of the same voltage level as the test product. The voltage measuring instrument is a voltmeter 8, and its rated voltage measurement range is consistent with the secondary voltage of the voltage transformer. The current measuring instrument is an ammeter 10, and its rated current measurement range is consistent with the secondary current of the current transformer. The above equipment can be used to view the effective values ​​of the voltage and current at the measuring point. Its access point is as follows: Figure 1 shown.

[0073] Connect the capacitors in series with the distribution network to the preset test circuit for full load testing, including:

[0074] It is necessary to ensure that the internal bypass switch of the test product is in the open state;

[0075] Connect the test product and the test device according to the above requirements;

[0076] Then the voltage is slowly increased through the voltage regulator. Due to the presence of the compensation capacitor, the current passing through the voltage regulator 4 and the intermediate transformer 5 is small, which will not cause overload of the voltage regulator 5, the intermediate transformer 4 and the test power supply 6. When the loop current reaches the rated current of the distribution network series compensation device, the distribution network series capacitor compensation device can be tested under full load.

[0077] The preset test circuit includes: the shunt reactor and the supplementary capacitor are connected in parallel and then connected to the intermediate transformer, and the intermediate transformer is connected to the power supply through the voltage regulator:

[0078] The distribution network series capacitor compensation device 1 is connected in series with the shunt reactor 2, and then connected in parallel with the compensation capacitor 3, and then connected to the secondary side of the intermediate transformer 4. The primary side of the intermediate transformer is connected to the power supply 6 through the voltage regulator 5. The voltage transformer and the current transformer are connected to the outlet side of the test product. The voltmeter 9 is connected to the secondary circuit of the voltage transformer 7, and short circuit is not allowed; the ammeter 10 is connected to the secondary circuit of the current transformer 8, and open circuit is not allowed. Specific embodiment:

[0080] exist Figure 1 In the embodiment shown, the distribution network series capacitor compensation device 1 is connected to the full-load test device as the device under test. The rated voltage of the distribution network series capacitor compensation device 1 is 10kV, the rated capacity is 2700kvar, the rated terminal voltage is 3kV, and the rated current is 300A. The shunt reactor 2 has a rated current of 300A, a rated voltage of 10kV, a rated reactance of 19.23Ω, a rated inductance of 61.21mH, and a rated capacity of 5193kvar. The compensation capacitor 3 is composed of 12 BFMH3.0-240-1W full-film capacitors, 4 in parallel per phase. The test transformer is composed of an 800kVA, 400V / 0~400V voltage regulating transformer 5 and an 800kVA, 400V / 10kV intermediate transformer. The primary power supply of the voltage regulator is 400V, 50Hz. The voltage transformer 7 has a transformation ratio of 10 / 0.1kV, and the current transformer has a transformation ratio of 400 / 5A. During the test, the distribution network series capacitor compensation device can be tested under full load by adjusting the parameters in Table 1 below.

[0081]

[0082]

[0083] Table 1

[0084] It can be seen from Table 1 that the output capacity of the test sample 1 branch is slightly larger than the output capacity of the compensation capacitor bank, which can enable the complete set of equipment to avoid the resonance point, protect the test equipment, and avoid the adverse consequences of complete resonance.

[0085] The present invention also provides a test system of a full-load test device, the system comprising:

[0086] A placement module is provided for connecting the device under test in series with the shunt reactor and then in parallel with the compensation capacitor, and connecting the detection device at the outlet of the device under test;

[0087] The adjustment test module is used to adjust the voltage regulator according to preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the device under test detects that the current reaches the rated current of the device under test and stops adjusting to obtain detection data.

[0088] The adjustment test module includes: an adjustment unit, a detection unit, a judgment unit and a test unit;

[0089] An adjusting unit, used for adjusting the voltage regulator to change the voltage of the intermediate transformer according to preset data;

[0090] A detection unit, used for detecting current and voltage through a detection device located at an outlet of the device under test;

[0091] A judging unit, used to judge whether the current detected by the detection device at the outlet of the device under test reaches the rated current of the device under test;

[0092] The acquisition unit is used to acquire detection data.

[0093] The detection unit includes a current detection subunit and a voltage detection subunit;

[0094] A current detection subunit, used for detecting loop current;

[0095] Voltage detection subunit, used to detect circuit voltage

[0096] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0097] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0098] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0099] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0100] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A full load test device, characterized in that: The device comprises: a power supply, a compensation capacitor, a detection device, a shunt reactor, a voltage regulator and an intermediate transformer; The shunt reactor is connected in series with the device under test and in parallel with the compensation capacitor, and then connected to the power supply through an intermediate transformer and a voltage regulator for adjusting the voltage of the intermediate transformer; The outlet of the device under test is connected to the detection device; The device under test includes: a distribution network series capacitor compensation device; The compensation capacitor comprises: the capacitive reactance value of the compensation capacitor is greater than the equivalent capacitive reactance value of the distribution network series capacitor compensation device connected in series with the shunt reactor; The compensation capacitors consist of 12 BFMH3.0-240-1W full-film capacitors, 4 in parallel per phase; The capacity of the shunt reactor should be equal to the rated current of the series capacitor compensation device of the distribution network; The distribution network series capacitor compensation device comprises: a capacitor, an inductor, a resistor, a first switch, a second switch, a third switch and a fourth switch; The inductor and the resistor are connected in parallel and in series with the fourth switch to form a third branch; The first switch constitutes a first branch; The capacitor constitutes a second branch; The two ends of the first branch are connected in parallel with the second branch through a second switch and a third switch respectively; the second branch is connected in parallel with the third branch.

2. The device according to claim 1, characterized in that The detection device comprises: a voltage transformer, a voltage meter, a current transformer and an ammeter; The voltage transformer and the current transformer are arranged at the outlet side of the device under test; The voltage transformer is connected in parallel with a voltmeter; The current transformer is connected in series with an ammeter.

3. The device according to claim 1, characterized in that The intermediate transformer comprises: a primary voltage rating of the intermediate transformer is equal to the maximum output voltage of the voltage regulator, and a secondary voltage rating ensures that the voltage value at both ends of the shunt reactor is equal to the rated voltage value.

4. The device according to claim 1, characterized in that The power supply comprises: A three-phase 50 Hz power supply, the rated voltage of which matches the input voltage of the voltage regulator.

5. A test method using the full-load test device as described in any one of claims 1 to 4, characterized in that: The method comprises: The device under test is connected in series with the shunt reactor and then in parallel with the compensation capacitor, and a detection device is connected at the outlet of the device under test; The voltage regulator is adjusted according to preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the distribution network series capacitor compensation device detects that the current reaches the rated current of the device under test, and then the adjustment is stopped to obtain the detection data.

6. The method according to claim 5, characterized in that The device under test is connected in series with the shunt reactor and then connected in parallel with the compensation capacitor, and before the detection device is connected at the outlet of the device under test, the method also includes: selecting an equipment model in a preset test circuit according to the device under test.

7. The method according to claim 6, characterized in that The device model in the preset test circuit is selected according to the device under test, including: The capacitive reactance value of the compensation capacitor is greater than the equivalent capacitive reactance value of the distribution network series capacitor compensation device connected in series with the shunt reactor; The primary voltage rating of the intermediate transformer is equal to the maximum output voltage of the voltage regulator, and the secondary voltage rating ensures that the voltage value across the shunt reactor is equal to the rated voltage value; The power supply is a three-phase 50 Hz power supply, and the rated voltage of the power supply matches the input voltage of the voltage regulator.

8. The method according to claim 5, characterized in that The detection device comprises: a voltage transformer, a voltage meter, a current transformer and an ammeter; The voltage transformer and the current transformer are arranged at the outlet side of the device under test; The voltage transformer is connected in parallel with a voltmeter; The current transformer is connected in series with an ammeter.

9. A test system for a full-load test device, characterized in that: The system comprises: A placement module is provided for connecting the device under test in series with the shunt reactor and then in parallel with the compensation capacitor, and connecting the detection device at the outlet of the device under test; The adjustment test module is used to adjust the voltage regulator according to the preset data to change the voltage of the intermediate transformer until the detection device located at the outlet of the device under test detects that the current reaches the rated current of the device under test, stops adjusting, and obtains the detection data; The device under test includes: a distribution network series capacitor compensation device; The distribution network series capacitor compensation device comprises: a capacitor, an inductor, a resistor, a first switch, a second switch, a third switch and a fourth switch; The inductor and the resistor are connected in parallel and in series with the fourth switch to form a third branch; The first switch constitutes a first branch; The capacitor constitutes a second branch; The two ends of the first branch are connected in parallel with the second branch through a second switch and a third switch respectively; the second branch is connected in parallel with the third branch.

10. The system according to claim 9, characterized in that The adjustment test module includes: an adjustment unit, a detection unit, a judgment unit and an acquisition unit; The regulating unit is used to adjust the voltage regulator to change the voltage of the intermediate transformer according to preset data; The detection unit is used to detect the current and voltage through the detection device located at the outlet of the device under test; The judging unit is used to judge whether the current detected by the detection device at the outlet of the device under test reaches the rated current of the device under test; The acquisition unit is used to acquire detection data.

11. The system according to claim 10, characterized in that The detection unit includes a current detection subunit and a voltage detection subunit; The current detection subunit is used to detect the loop current; The voltage detection subunit is used to detect the circuit voltage.

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