CN110161446A - Relay protection device for high-voltage dc voltage mutual inductor - Google Patents

Abstract

The invention discloses a transient test device for a high voltage direct current voltage transformer, comprising a high voltage direct current charging power supply, a direct current square wave generator, a high voltage standard device, a voltage transformer, a transformer transient calibrator, a PC terminal and the like , so that the transient test of the voltage transformer is realized through the high-voltage DC charging power supply, etc.; moreover, the DC square wave generator includes several charging and discharging units connected in parallel and a Therefore, by changing the number of the charging and discharging units, the high voltage output by the DC square wave generator can be adjusted to meet the transient test requirements of voltage transformers of different voltage levels.

Description

Transient test device for high voltage DC voltage transformers

technical field

The invention relates to the technical field of power grid detection, in particular to a transient test device for a high-voltage direct current voltage transformer.

Background technique

HVDC technology is widely used due to its advantages of long distance, large capacity and no synchronization problems. However, due to the small circuit impedance of the DC side fault in the HVDC It will generate a large fault current, which requires the control and protection signal to have a faster sampling speed and a wider bandwidth, which puts forward higher requirements for the transient response of the transformer in the DC transmission system. It is necessary to carry out on-site calibration and test verification of the transformer before use.

According to the national standard GB/T 26217-2010 "DC voltage measurement device for high-voltage DC transmission system", the "transient response" of the DC voltage measurement device is the response of the secondary voltage to the transient change of the primary voltage, which requires Apply a step voltage over 10% of the measurement range to the high-voltage terminal of the measuring device, and measure the transient response of the output terminal. The response time at this time should not be greater than 250us, and as a test device, a voltage with a response time much shorter than the response time should be provided. waveform, reaching the order of 10us. However, due to the lack of relevant theoretical research and the lack of corresponding testing equipment, the transient test for the voltage transformer cannot be carried out normally.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the technical problem solved by the present invention is to provide a transient test device and a control method for high-voltage DC voltage transformers, which can perform transient tests for high-voltage DC voltage transformers connected to the grid.

In order to solve the above-mentioned technical problems, the content of the technical solution adopted in the present invention is as follows:

A transient test device for a high-voltage DC voltage transformer, comprising a high-voltage DC charging power supply, a DC square wave generator, a high-voltage standard, a voltage transformer, a transformer transient calibrator and a PC terminal, wherein: the The high-voltage DC charging power supply is used to charge the DC square wave generator, and the DC square wave generator is used to upgrade the received charging voltage and transmit the upgraded voltage to the high-voltage standard device and the voltage Transformer, the transformer transient calibrator is used to sample the signals output by the high-voltage standard device and the voltage transformer, and transmit the sampled signals to the PC end, and the PC end uses It is used to calculate, store and display the received signal.

Further, the DC square wave generator includes a plurality of charging and discharging units connected in parallel and a relay switch assembly for controlling the working state of the charging and discharging units, and each charging and discharging unit includes an energy storage capacitor, an IGBT switch, The first diode and the second diode, the first diode, the energy storage capacitor and the second diode are sequentially connected in series and then connected in parallel with the IGBT switch.

Further, the relay switch assembly includes a first relay switch arranged at the input end of the first diode, a second relay switch arranged at the output end of the high-voltage standard and the voltage transformer, and a second relay switch arranged at the ground terminal. A third relay switch at the resistor output.

Furthermore, the transformer transient calibrator includes a first signal interface for connecting to the high-voltage standard, and a second signal interface for connecting to the voltage transformer.

Further, the transient test device further includes a remote digital module connected to the voltage transformer, and an output end of the remote digital module is connected to the transformer transient calibrator.

Further, the high voltage DC charging power supply, the DC square wave generator, the high voltage standard device and the voltage transformer are all provided with ground terminals.

Further, the transformer transient calibrator includes an isolated sampling and communication unit connected to the high-voltage standard device and the voltage transformer, and a host connected to the isolated sampling and communication unit, so The isolated sampling and communication unit is connected with the host through an optical fiber.

The invention also discloses a transient test method for the high voltage direct current voltage transformer, comprising the following steps:

S1: Control the on and off states of the relay switch assembly, so that the high-voltage DC charging power supply charges the DC square wave generator with a set charging voltage;

S2: After the charging of the DC square wave generator is completed, the on and off states of the relay switch components are controlled, and the IGBT switch is turned on at the same time, so that the DC square wave generator discharges, and the released voltage is transmitted to the high-voltage standard and all said voltage transformer;

S3: The transformer transient calibrator samples the signals output by the high-voltage standard device and the voltage transformer, and transmits the sampled signals to the PC terminal;

S4: The PC terminal calculates, stores and displays the received signal.

Further, step S1 is specifically: turning on the first relay switch, turning off the second relay switch, the third relay switch and the IGBT switch, then the high-voltage DC charging power supply will charge the DC square wave generator, and After the charging current flows through the first diode, the energy storage capacitor will be charged in parallel.

Further, step S2 is specifically: turning on the second relay switch, turning off the first relay switch and the third relay switch, and turning on the IGBT switch, then the first diodes, the energy storage capacitors and the second diodes will The discharge is performed after being connected in series, and the discharged voltage is transmitted to the high voltage standard and the voltage transformer.

Compared with the prior art, the beneficial effects of the present invention are:

The invention discloses a transient test device for a high voltage direct current voltage transformer, comprising a high voltage direct current charging power supply, a direct current square wave generator, a high voltage standard device, a voltage transformer, a transformer transient calibrator, a PC terminal, etc. , so that the transient test of the voltage transformer is realized through the high-voltage DC charging power supply, etc.; moreover, the DC square wave generator includes a plurality of charging and discharging units connected in parallel and a Therefore, by changing the number of the charging and discharging units, the high voltage output by the DC square wave generator can be adjusted to meet the transient test requirements of voltage transformers of different voltage levels.

The above description is only an overview of the technical solutions of the present invention, in order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand , the following specific preferred embodiments, and in conjunction with the accompanying drawings, are described in detail as follows.

Description of drawings

1 is a schematic structural diagram of a transient test device for a high DC voltage transformer according to the present invention;

Fig. 2 is the circuit diagram when the DC square wave generator is in the charging state;

Fig. 3 is the circuit diagram when the DC square wave generator is in the discharge state;

4 is a schematic diagram of performing a transient test using the transient test device for a high DC voltage transformer according to the present invention;

FIG. 5 is a schematic flowchart of the transient test method for a high-voltage DC voltage transformer according to the present invention;

Among them, the reference numerals in Fig. 1-Fig. 4 are:

1. High voltage DC charging power supply; 2. DC square wave generator; 3. High voltage standard device; 4. Voltage transformer; 5. Transformer transient calibrator; 6. PC terminal; 7. Isolated sampling and communication unit; 8. Host; 9. Remote digital module; 10. First diode; 11. Energy storage capacitor; 12. IGBT switch; 13. First relay switch; 14. Second relay switch; 15. Third relay switch ; 16, the second diode.

Detailed ways

In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, below in conjunction with the accompanying drawings and preferred embodiments, the specific embodiments, structures, features and effects according to the present invention are described in detail as follows:

As shown in FIG. 1, the present invention discloses a transient test device for a high-voltage DC voltage transformer, which includes a high-voltage DC charging power supply 1, a DC square wave generator 2, a high-voltage standard 3, a voltage transformer 4, Transformer transient calibrator 5 and PC terminal 6, wherein: the high-voltage DC charging power supply 1 is used to charge the DC square wave generator 2, and the DC square wave generator 2 is used to charge the received The voltage is upgraded, and the upgraded voltage is transmitted to the high-voltage standard device 3 and the voltage transformer 4, and the transformer transient calibrator 5 is used for the high-voltage standard device 3 and the voltage transformer. The signal output by the device 4 is sampled, and the sampled signal is transmitted to the PC terminal 6, and the PC terminal 6 is used to calculate, store and display the received signal, so as to pass the high-voltage DC charging power supply 1, etc. The transient test of the voltage transformer is realized.

In the present invention, the basic function of the high-voltage DC charging power supply 1 is to generate a voltage of the magnitude of kV, and supply the voltage to the DC square wave generator 2 for boosting. Voltage, over-current and over-temperature protection functions; the main function of the DC square wave generator 2 is to upgrade the charging voltage input by the high-voltage DC charging power supply 1, and transmit the upgraded voltage to the high-voltage standard device 3 and the voltage transformer 4, and the magnitude of the voltage upgrade depends on the size of the charging voltage input by the high-voltage DC charging power supply 1 and the internal circuit and cascading mode of the DC square wave generator 2; the voltage mutual inductance The device 4 is an important primary device for high-voltage measurement in the DC power transmission project; the high-voltage standard device 3, as a measuring instrument, needs to be calibrated before use, and has a waveform rise response time of less than 1 μs; the PC terminal 6 is used for receiving The information is calculated, stored and displayed.

The DC square wave generator 2 includes several charging and discharging units connected in parallel and a relay switch assembly for controlling the working state of the charging and discharging units. Therefore, by changing the number of the charging and discharging units, the DC square wave can be adjusted. The size of the high-voltage electricity output by the wave generator 2 is adjusted to meet the transient test requirements of the voltage transformers 4 of different voltage levels.

As shown in FIG. 2 and FIG. 3 , each of the charging and discharging units includes a storage capacitor 11 , an IGBT switch 12 , a first diode 10 and a second diode 16 . The energy storage capacitor 11 and the second diode 16 are sequentially connected in series and then connected in parallel with the IGBT switch 12 ; the relay switch assembly includes a first relay switch 13 disposed at the input end of the first diode 10 . , a second relay switch 14 arranged at the output end of the high voltage standard device 3 and the voltage transformer 4 and a third relay switch 15 arranged at the output end of the grounding small resistance.

Specifically, as shown in FIG. 2 , when the DC square wave generator 2 is in a charging state, the first relay switch 13 is turned on, and the second relay switch 14 and the third relay switch 15 are turned off. , and the IGBT switches 12 are all in the off state; at this time, the high-voltage DC charging power supply 1 will charge the DC square wave generator 2, and during charging, the charging current flows through the first diode After 10, the storage capacitor 11 will be charged in parallel. Assuming that the charging voltage is U ₀ , after charging, the voltage on each energy storage capacitor 11 is U ₀ -(n+1)V _f , where n is the number of stages included in the DC square wave generator 2 , and V _f It is the forward conduction voltage drop of the first diode 10 . Generally, the voltage drop of the first diode 10 can be ignored. It can be considered that the voltages of the energy storage capacitors 11 at all levels after charging are all U ₀ .

As shown in FIG. 3 , when the DC square wave generator 2 is in a discharge state, the voltage of each energy storage capacitor 11 is U ₀ , each of the IGBT switches 12 , the first diode 10 and the first The two diodes 16 are both in the off state, and the current is zero; then the IGBT switches 12 at all levels are triggered to conduct, and the triggering mode of the IGBT switches 12 is the synchronous contact of the optical fiber. Therefore, each of the first diodes 10 and the second diode 16 will be reverse biased and turned off, so that the energy storage capacitors 11 are connected in series to discharge the high-voltage standard 3 and the voltage transformer 4, and obtain more power on the load. times the U ₀ negative polarity pulse.

In addition, the DC square wave generator 2 also has a standby state, that is, the first relay switch 13 and the second relay switch 14 are disconnected, and the third relay switch 15 is closed, and the IGBT switches 12 are all in a controllable conduction state. , so that the electricity that is not completely discharged in each of the energy storage capacitors 11 is completely discharged through the small grounding resistance, so as to ensure that the DC square wave generator 2 is in a safe and voltage-free working condition.

As shown in FIG. 1 , the transformer transient calibrator 5 includes a first signal interface for connecting to the high-voltage standard device 3 and a second signal interface for connecting to the voltage transformer 4. Specifically, the connection is as follows: , the output end of the high voltage standard device 3 is connected to the first signal interface through a cable, and the output end of the voltage transformer 4 is connected to the second signal interface through a cable.

As a further preferred embodiment, the transient test device further includes a remote digital module 9 connected to the voltage transformer 4, and the output end of the remote digital module 9 is connected to the transformer for transient verification. instrument 5 , so that the transformer transient calibrator 5 can be applied to both cases with the remote digital module 9 and without the remote digital module 9 . Moreover, in the test, it is enough to directly sample and compare the secondary analog signal of the voltage transformer 4 and the secondary analog signal of the high-voltage standard 3, and when the voltage transformer 4 is connected with a remote digital module At 9 o'clock, it is necessary to connect the remote digital module 9 and the host 8 through an optical fiber, and then perform waveform comparison after data analysis and time delay compensation.

As shown in FIG. 1 , the high-voltage DC charging power supply 1 , the DC square wave generator 2 , the high-voltage standard device 3 and the voltage transformer 4 are all provided with ground terminals.

In order to facilitate the data collection by the transformer transient calibrator 5, the transformer transient calibrator 5 includes an isolated sampling and communication unit 7 connected to the high-voltage standard 3 and the voltage transformer 4, and a host computer 8 connected to the isolation sampling and communication unit 7, the isolation sampling and communication unit 7 and the host computer 8 are connected by optical fibers.

As shown in FIG. 5 , the present invention also discloses a transient test method for a high-voltage DC voltage transformer, which includes the following steps:

S1: Set the charging voltage of the high-voltage DC charging power source 1 .

In the present invention, the high voltage DC charging power source 1 is used to charge the DC square wave generator 2, and the charging voltage is set to U ₀ .

S2: Connect the high-voltage DC charging power source 1 and the DC square wave generator 2, and control the on/off state of the relay switch assembly, so that the high-voltage DC charging power source 1 charges the DC square wave generator.

Specifically, step S2 is: turning on the first relay switch 13, turning off the second relay switch 14, the third relay switch 15 and each of the IGBT switches 12, at this time the high-voltage DC charging power supply 1 will charge the DC square wave generator 2, and after the charging current flows through the first diode 10, the energy storage capacitor 11 will be charged in parallel. During the charging process, observe the voltage of the output terminal of the high-voltage DC charging power supply 1 until the voltage of the high-voltage DC charging power supply 1 rises to _U0 and remains stable, indicating that the charging is completed, that is, the voltage of each energy storage capacitor 11 approximately reaches U ₀ .

S3 : Control the on/off state of the relay switch assembly, and turn on the IGBT switch 12 at the same time, so that the DC square wave generator 2 discharges, and the discharged voltage is transmitted to the high-voltage standard 3 and the voltage transformer 4 .

Specifically, step S3 is: turning on the second relay switch 14, turning off the first relay switch 13 and the third relay switch 15, at this time, each of the IGBT switches 12 is in an off state; Set the transformer transient calibrator 5, if the secondary output of the voltage transformer 4 is an analog quantity, only the secondary changes of the high voltage standard 3 and the voltage transformer 4 need to be set; if If the output of the voltage transformer 4 is a digital quantity, not only the secondary changes of the high voltage standard 3 and the voltage transformer 4 should be set, but also the inherent delay time of the voltage transformer 4; Then, the transformer transient calibrator 5 is controlled to be in a ready state for triggering, and the trigger source is the secondary conversion voltage in the channel 3 of the high-voltage standard device; then, the IGBT switch 12 is turned on, and each first diode The tube 10, the energy storage capacitor 11 and the second diode 16 will be connected in series for discharge, and the released voltage will be transmitted to the high-voltage standard device 3 and the voltage transformer 4, that is, the DC square wave generator 2. The released current will pass through the high-voltage standard device 3 and the voltage transformer 4, and the duration of discharge is controlled at about 10ms. Both the high-voltage standard device 3 and the voltage transformer 4 bear the test voltage.

S4 : The transformer transient calibrator 5 samples the signals output by the high-voltage standard device 3 and the voltage transformer 4 , and transmits the sampled signals to the PC terminal 6 .

Specifically, if the secondary conversion output of the voltage transformer 4 is an analog quantity, the isolation sampling and communication unit 7 collects the voltages in the channels of the voltage transformer 4 and the high-voltage standard 3. Once When the size of the collected voltage reaches the trigger reserved value, the isolated sampling and communication unit 7 performs AD conversion on the collected voltage and stores it, and transmits the converted data to the host 8 at the same time. Since the isolation sampling and communication unit 7 is a high-speed analog sampling, it can be considered as a sampling signal without delay, and the digital signal transmitted from the remote digital module 9 will generate an inherent delay in the processing process, This is an inherent characteristic of the voltage transformer 4 and requires an accurate compensation, and the delay data is provided by the manufacturer of the voltage transformer 4 .

In addition, as shown in FIG. 4 , the calculation method of the waveform result is: firstly, compare the data of the high-voltage standard device 3 and the voltage transformer 4, and when the voltage transformer 4 is connected to the remote digital module 9 o’clock, for example, when the inherent time delay of the voltage transformer 4 is 0.125ms, and this part of the delay is compensated, the sampling waveform of the transient voltage can basically coincide with the analog sampling wave of the high-voltage standard 3, and the compensation amount is determined by PC terminal 6 sends it, and when the voltage transformer 4 is directly connected to the analog output, no time synchronization is required.

S5: The PC terminal 6 calculates, stores and displays the received signal.

Specifically, the transformer transient calibrator 5 transmits the two-way test data to the PC terminal 6, and then the PC terminal 6 calculates the measurement error. The main contents of the measurement error include rise time, peak value, and instantaneous error, wherein the instantaneous error It is the error between all sampling points of the two sets of sampling data in the whole test process, and the maximum error value between the two points is the maximum instantaneous error; the national standard has clear restrictions on multiple measurement errors of the voltage transformer 4. Compared with the high-voltage standard Quantitative analysis of the results can be done by analyzing the data of 3 channels of the transformer and 4 channels of the voltage transformer.

The above-mentioned embodiments are only preferred embodiments of the present invention, and cannot be used to limit the scope of protection of the present invention. Any insubstantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of the present invention. Scope of protection claimed.

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

Claims (10)

1. a kind of transient test device for high voltage direct current voltage transformer, it is characterized in that: comprise high voltage direct current charging power supply, direct current square wave generator, high voltage standard device, voltage transformer, transformer transient calibrator and PC terminal, wherein: the high voltage DC charging power supply is used to charge the DC square wave generator to which it belongs, and the DC square wave generator is used to upgrade the received charging voltage and transmit the upgraded voltage to the high voltage standard and the voltage transformer, the transformer transient calibrator is used to sample the signals output by the high-voltage standard device and the voltage transformer, and transmit the sampled signals to the PC terminal. The PC terminal is used to calculate, store and display the received signal. 2. The transient test device according to claim 1, wherein the DC square wave generator comprises a plurality of charging and discharging units connected in parallel and a relay switch assembly for controlling the working state of the charging and discharging units, Each of the charging and discharging units includes an energy storage capacitor, an IGBT switch, a first diode and a second diode, and the first diode, the energy storage capacitor and the second diode are connected in series in sequence After being connected, it is connected in parallel with the IGBT switch. 3 . The transient test device according to claim 2 , wherein the relay switch assembly comprises a first relay switch arranged at the input end of the first diode, a first relay switch arranged at the high voltage standard and the The second relay switch at the output end of the voltage transformer and the third relay switch arranged at the output end of the grounding small resistance. 4 . The transient test device according to claim 1 , wherein the transformer transient calibrator comprises a first signal interface for connecting to the high-voltage standard, and a first signal interface for connecting the voltage transformer. 5 . The second signal interface of the device. 5. The transient test device according to claim 1, characterized in that: the transient test device further comprises a remote digital module connected with the voltage transformer, and the output end of the remote digital module is connected to The transformer transient calibrator. 6 . The transient test device according to claim 1 , wherein the high-voltage DC charging power supply, the DC square wave generator, the high-voltage standard device and the voltage transformer are all provided with ground terminals. 7 . 7. The transient test device for a high DC voltage transformer according to any one of claims 1 to 6, wherein the transformer transient calibrator comprises a combination of the high voltage standard and the The isolated sampling and communication unit connected with the voltage transformer, and the host connected with the isolated sampling and communication unit, the isolated sampling and communication unit is connected with the host through an optical fiber. 8. A transient test method for high-voltage direct current voltage transformer, characterized in that: comprising the steps: S1: Control the on and off states of the relay switch assembly, so that the high-voltage DC charging power supply charges the DC square wave generator with a set charging voltage; S2: After the charging of the DC square wave generator is completed, the on and off states of the relay switch components are controlled, and the IGBT switch is turned on at the same time, so that the DC square wave generator discharges, and the released voltage is transmitted to the high-voltage standard and all said voltage transformer; S3: The transformer transient calibrator samples the signals output by the high-voltage standard device and the voltage transformer, and transmits the sampled signals to the PC terminal; S4: The PC terminal calculates, stores and displays the received signal. 9. The transient test method for a high-voltage DC voltage transformer according to claim 7, wherein step S1 is specifically: turning on the first relay switch, turning off the second relay switch, the third relay switch, and Each IGBT is switched on and off, the high voltage DC charging power supply will charge the DC square wave generator, and the charging current will charge the energy storage capacitor in parallel after flowing through the first diode. 10. The transient test method for a high-voltage direct current voltage transformer according to claim 7, wherein step S2 is specifically: turning on the second relay switch, turning off the first relay switch and the third relay switch, When each IGBT switch is turned on, each first diode, energy storage capacitor and second diode will be connected in series and then discharged, and the released voltage will be transmitted to the high voltage standard device and the voltage transformer.