CN204177919U - Based on the high direct voltage impact system of air reactor - Google Patents

Abstract

The utility model relates to a DC high-voltage impact system based on an air-core reactor. The high-voltage electronic switch device is connected in parallel with the series branch composed of adjustable capacitors and dry-type air-core reactors. The remote control chassis is connected to the power supply through the main circuit wiring, and the remote control chassis is also connected to the high-voltage electronic switch device through communication wiring. The remote control chassis is connected to the oscilloscope through the test wiring, and the test voltage divider and the partial discharge test impedance are connected to the oscilloscope through the communication wiring. The high-voltage electronic switch device charges and discharges the adjustable capacitor to realize the charge and discharge of the dry-type air-core reactor, and the test voltage divider detects the discharge spectrum of the dry-type air-core reactor to determine whether the dry-type air-core reactor is damaged. The capacitor makes the frequency of the pulse oscillation voltage 50Hz.

Description

DC High Voltage Impulse System Based on Air Core Reactor

technical field

The utility model relates to a DC high-voltage impact system based on an air-core reactor.

Background technique

The insulation defect detection of series air-core reactors and shunt reactors in the power system, the inter-turn insulation state of the reactor cannot be monitored during the entire operation period, and the reliability of its operation mainly depends on the quality of the product itself (the operation risk is high ) The power grid has repeatedly caught fire, especially in unattended substations, and the consequences are more serious. Especially for reactors that are still in operation and have a lifespan of several to ten years, some of them have major safety hazards.

The existing detection method is to use DC boost to charge the capacitor C, and then close the switch, so that LC damping oscillation occurs between the capacitor C and the reactor LX, the measured oscillation frequency is f1, which is a single oscillation, and the attenuation rate is calculated at the same time delt 1, Y(t) as a transfer function;

Then periodically open and close the switch, so that the damping oscillation continues to occur, and the DC voltage is increased to obtain the frequency of the damping oscillation as f2, and the attenuation rate delt 2 is calculated as X(t) of the transfer function;

By comparing f1 and f2, comparing the attenuation rate delt1 and delt2, and the transfer function of the W(t)=Y(t)/X(t) system, the insulation defect of the test product can be identified;

However, using the existing technology (dry reactor overvoltage test): the resonant capacitance is 3000pF and the following table 1 is obtained after continuous discharge:

Table 1

Comparing the two test schemes, it can be detected that there is a hidden danger in the reactor that has been in operation for 8 years, but the existing technology can effectively identify that the initial discharge voltage needs to be increased to DC 50kV and 55KV to effectively detect the insulation problem of the reactor. .

Although this test plan and detection method (turn-to-turn overvoltage test) use DC to charge the capacitor, and use the ball gap to discharge the air-core reactor instantaneously to form an attenuating oscillation wave, and use the frequency to judge whether there is a defect; but there are deficiencies: due to the ball gap The discharge is affected by the weather and humidity, and the discharge voltage is inconsistent each time; the power frequency doubler rectifier is used to charge the capacitor, which is bulky and not conducive to on-site testing; when the test plan tests the reactor, as the voltage rises, the reactance Insulation damage of the device due to the test.

Contents of the invention

The purpose of the utility model is to overcome the deficiencies of the prior art and provide a DC high-voltage impact system based on an air-core reactor.

The purpose of this utility model is achieved through the following technical solutions:

The DC high-voltage impact system based on air-core reactors is characterized by: including adjustable capacitors, dry-type air-core reactors, power supplies, charging resistors, high-voltage electronic switching devices, test voltage dividers and partial discharge test resistors, power supplies, charging resistors, The adjustable capacitor and the dry-type air-core reactor are connected in series to form a closed circuit, the series branch composed of the test voltage divider and the partial discharge test resistor is connected in parallel with the dry-type air-core reactor, and the high-voltage electronic switch device is connected in parallel with the adjustable capacitor and the dry-type air-core reactor. A series branch composed of reactors, the remote control chassis is connected to the power supply through the main circuit wiring, the remote control chassis is also connected to the high-voltage electronic switch device through the communication wiring, the remote control chassis is connected to the oscilloscope through the test wiring, and the voltage divider and The partial discharge test resistors are all connected to the oscilloscope through communication wiring; the high-voltage electronic switch device is composed of several layers of high-voltage electronic switches connected in series. The freewheeling diode and the voltage equalizing resistor are connected in parallel, and the thyristor and the freewheeling diode are connected in reverse.

Further, the above-mentioned air-core reactor-based DC high-voltage impact system, wherein the adjustable capacitor is a linear adjustment capacitor of 0.1uF-10uF.

Furthermore, in the above-mentioned air-core reactor-based DC high-voltage impact system, the high-voltage electronic switches between the layers are separated by metal partitions.

The substantive features and progress of the technical solution of the utility model are mainly reflected in:

The high-voltage electronic switch device is used to complete the connection and disconnection of the test circuit to generate pulse oscillating voltage. The high-voltage electronic switch device has precise controllability and can be used to improve the controllable range. The high-voltage electronic switch device is used to charge and discharge the adjustable capacitor. To realize the charge and discharge of the dry-type air-core reactor, and use the test voltage divider to detect the discharge spectrum of the dry-type air-core reactor to judge whether the dry-type air-core reactor is damaged. By adjusting the adjustable capacitor, the pulse oscillation voltage can be adjusted. The frequency is 50Hz, which is consistent with the frequency of the actual power supply, and the detection standard is closer to the actual effect.

Description of drawings

Below in conjunction with accompanying drawing, technical scheme of the utility model is further described:

Fig. 1: structural block diagram of the present utility model;

Figure 2: Schematic diagram of the principle structure of a high-voltage electronic switch.

Detailed ways

As shown in Figure 1, the DC high-voltage impact system based on the air-core reactor of the utility model includes an adjustable capacitor 5, a dry-type air-core reactor 6, a power supply 3, a charging resistor 4, a high-voltage electronic switch device 9, and a test voltage divider 7 and the partial discharge test resistor 8, the power supply 3, the charging resistor 4, the adjustable capacitor 5 and the dry-type air-core reactor 6 are connected in series to form a closed loop, and the series branch formed by the test voltage divider 7 and the partial discharge test resistor 8 is connected to The dry-type air-core reactor 6 is connected in parallel, and the high-voltage electronic switch device 9 is connected in parallel to the series branch composed of the adjustable capacitor 5 and the dry-type air-core reactor 6. The remote control chassis 1 is connected to the power supply 3 through the main circuit wiring, and the remote control chassis 1 is also The remote control cabinet 1 is connected to the oscilloscope 2 through the test wiring, and the test voltage divider 7 and the partial discharge test impedance 8 are connected to the oscilloscope 2 through the communication wiring.

When the high-voltage electronic switch is turned off, the voltage of the power supply 3 directly charges the adjustable capacitor 5 through the charging resistor 4, and after the high-voltage electronic switch is closed, the adjustable capacitor 5 with full energy storage discharges the dry-type air-core reactor 6, The dry-type air-core reactor 6 is tested by the test voltage divider 7 and the partial discharge test resistor 8 , and is displayed by the oscilloscope 2 .

As shown in Figure 2, the high-voltage electronic switch device 9 is composed of several layers of high-voltage electronic switches connected in series. The equalizing resistors are connected in parallel, and the thyristor and the freewheeling diode are reversely connected.

The specific working process is as follows:

1) Input the actual calibrated inductance, and the adjustable capacitor 5 is automatically adjusted so that the frequency of the impulse voltage is 50Hz;

2), DC boost: According to the regulations, first boost the voltage to the required test voltage, and charge the adjustable capacitor 5 through the charging resistor 4 (the function of the adjustable capacitor 5 is to store energy during the boosting process);

3) Start the high-voltage discharge, start the high-voltage discharge to adjust the capacitor 5 (closed by the high-voltage electronic switch), then the adjustable capacitor 5 is a resonant capacitor when discharging, at this time, the adjustable capacitor 5 and the dry-type air-core reactor 6 form an LC oscillation , through the adjustable capacitor 5 and the dry-type air-core reactor 6 to form an LC resonant circuit to form an impulse voltage, and measure the waveform and frequency of the impulse voltage; with the increase of the test voltage, the waveform and frequency of the impulse voltage will change accordingly, which can be judged The insulation level of the dry-type air-core reactor 6, and then judge whether the dry-type air-core reactor 6 can continue to operate or be replaced according to national standards.

The DC high-voltage power supply charges the adjustable capacitor 5, and then closes the loop between the dry-type air-core reactor 6 and the adjustable capacitor 5, and an impulse voltage is formed between the capacitor and the inductance, and the impulse voltage is used to test the insulation strength of the air-core reactor. The frequency of the impulse voltage is 50Hz, which is determined by f=1/(2π√L╳C), and C can be adjusted and matched so that f=50Hz.

The utility model uses a high-voltage electronic switch device to complete the connection and disconnection of the test circuit to generate an inductive coil for pulse oscillation voltage. The high-voltage electronic switch device has precise controllability, which can improve the controllable range by using the high-voltage electronic switch device. The charge and discharge of the adjustable capacitor is used to realize the charge and discharge of the dry-type air-core reactor. At the same time, the test voltage divider and partial discharge test resistor are used to detect the partial discharge of the dry-type air-core reactor to determine whether the dry-type air-core reactor is damaged. , the device can effectively reduce the initial voltage to ensure that the insulation of the inductive coil is not damaged.

It should be understood that: the above is only a preferred embodiment of the utility model, for those of ordinary skill in the art, without departing from the principle of the utility model, some improvements and modifications can also be made, these Improvement and retouching should also be regarded as the protection scope of the present utility model.

Claims (3)

1. based on the high direct voltage impact system of air reactor, it is characterized in that: comprise tunable capacitor, dry-type air-core reactor, power supply, charging resistor, high-pressure electronic switchgear, Impedance measurement device is put in the drawn game of test voltage divider, power supply, charging resistor, tunable capacitor and dry-type air-core reactor are composed in series closed-loop path, the series arm that Impedance measurement device composition is put in the drawn game of test voltage divider is in parallel with dry-type air-core reactor, high-pressure electronic switchgear is parallel to the series arm of tunable capacitor and dry-type air-core reactor composition, Long-distance Control cabinet is connected with power supply by major loop wiring, described Long-distance Control cabinet is also connected with high-pressure electronic switchgear by communications line, Long-distance Control cabinet is connected with oscillograph by test wiring, the drawn game of test voltage divider is put Impedance measurement device and is all connected with oscillograph by communications line, described high-pressure electronic switchgear is superposed by the high-pressure electronic switch of some layers of series connection and forms, high-pressure electronic switch comprises controllable silicon, fly-wheel diode, equalizing resistance, controllable silicon, fly-wheel diode, equalizing resistance are in parallel, controllable silicon and fly-wheel diode Opposite direction connection.

2. the high direct voltage impact system based on air reactor according to claim 1, is characterized in that: described tunable capacitor is 0.1uF ~ 10uF linear regulation electric capacity.

3. the high direct voltage impact system based on air reactor according to claim 1, is characterized in that: described high-pressure electronic switch is between layers separated by metal partion (metp).