CN101236228A - A multi-waveform aging test device for surge arresters - Google Patents

Abstract

The present invention relates to a variety of waveform aging test devices for AC and DC arresters, which includes: three ovens, multiple waveform generators, back-to-back simulation devices, and a measurement and control system; multiple waveform generators and back-to-back simulation devices pass through multiple high-voltage lead cables The voltage signal is introduced into the oven and applied to the test object; at the same time, the oven heats the test object; the measurement and control system uses the acquisition card to collect the voltage waveforms on the sampling resistor R ₁ and the voltage divider R ₂ respectively, and compares the current and withstand voltage of the test object The voltage waveform of the sample is collected into the computer, and the power consumption and other parameters of the test product are calculated through mathematical analysis. The invention inputs the current in the test product and various voltage waveforms to the computer through the waveform acquisition system, calculates the power consumption of the test product and other data through mathematical analysis, and conducts comprehensive research on the accelerated aging test method of the AC and DC arrester.

Description

A multi-waveform aging test device for surge arresters

technical field

The invention relates to a test device, in particular to a test device for multiple waveform aging tests of a lightning arrester.

Background technique

In practical application, the aging characteristic of arrester is its key performance, which is related to the safety and reliability of arrester operation. Therefore, it is necessary to conduct an accelerated aging test on the arrester to investigate its aging characteristics, and the equivalent method is used for the test and inspection. At present, a lot of work has been done on the aging test of AC arresters at home and abroad, which can be based on national standards and IEC standards. However, for DC arresters, due to the complexity and diversity of their operating voltages, there is no unified national or international standard for accelerated aging tests. At present, the arrester aging test equipment at home and abroad is specially designed for the aging test of AC arresters or DC arresters. The functions are relatively single and the test capabilities are limited, which is not conducive to comprehensive test research.

Contents of the invention

In view of the above problems, the object of the present invention is to provide a multi-waveform aging test device for arresters that can be comprehensively used in various waveform accelerated aging tests of AC and DC arresters.

In order to achieve the above object, the present invention adopts the following technical solutions: a multi-waveform aging test device for lightning arresters, which includes multiple ovens, multiple waveform generators, back-to-back simulation devices and measurement and control systems, characterized in that: multiple waveform generators The multi-channel voltage signal sent by the back-to-back analog device is introduced into the oven through the high-voltage lead cable; the voltage divider and the sampling resistor are installed outside the oven, the voltage divider is connected in parallel to the two ends of the test sample in the oven through the cable, and the sampling resistor and the test sample in the oven are connected in parallel. The products are connected in series; the measurement and control system uses the acquisition card to collect the current waveform and voltage waveform on the sampling resistor and the voltage divider respectively.

The AC and DC signal waveforms output by the various waveform generators, the switching between different waveforms is controlled by switches.

Because the present invention adopts the above technical scheme, it has the following advantages: 1. The present invention comprehensively develops modules such as oven, various waveform generators, back-to-back simulation devices, measurement and control systems, so that the overall equipment has the ability to carry out comprehensive tests. 2. The present invention inputs the current in the sample and the various voltage waveforms it bears into the computer through the waveform acquisition system, calculates data such as power consumption of the sample through mathematical analysis, and conducts comprehensive research on the accelerated aging test method of the AC/DC arrester.

Description of drawings

Fig. 1 is a module block diagram of the present invention

Fig. 2 is a schematic diagram of various waveform generator circuits of the present invention

Fig. 3 is a schematic diagram of the back-to-back simulation device of the present invention

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, the present invention includes: three ovens, various waveform generators, back-to-back simulation devices, and a measurement and control system. A variety of waveform generators and back-to-back analog devices introduce voltage signals into the oven through multiple high-voltage lead cables and apply them to the test object (arrester proportional unit). At the same time, the oven heats the sample to simulate the actual operating environment. The voltage divider R ₂ and the sampling resistor R ₁ are installed outside the oven, the voltage divider R ₂ is connected in parallel to both ends of the test sample in the oven through cables, and the sampling resistor R ₁ is connected in series with the test sample in the oven. The measurement and control system uses a computer as the main control device, and the computer controls the acquisition card to collect the signal waveforms on the sampling resistor _R1 and the voltage divider _R2 respectively, and then input the current in the test sample and the voltage waveform it withstands to the computer, through Mathematical analysis calculates parameters such as power consumption of test samples. At the same time, the measurement and control system controls the switching operation of the relay through the computer-controlled programmable logic controller (PLC), so as to switch the waveform applied to the test object. In the measurement and control system, computer-controlled acquisition card and computer-controlled programmable logic controller (PLC) to further control the switching operations of relays are mature technologies in this field, and will not be described in detail here.

When the test device is used to check the aging characteristics of DC arresters or AC arresters, different waveforms are required. A variety of waveform generators can output up to 27 signal waveforms, and provide voltage signals to the oven according to a certain combination. Among them, there are 15 channels of waveforms. Since they are completely common AC outputs, no special settings are required, and they can be directly derived from the AC source. As shown in Figure 2, it is the generating circuit of the remaining 12 signals, in which AC is the AC voltage source, the test sample to be tested is connected between the output points 1 and 2, through the switches K ₁ , K ₂ , K ₃ , K ₄ Switching connects rectifier silicon stacks D ₁ , D ₂ , D ₃ , D ₄ and filter capacitor C into the circuit respectively, so as to control the output waveform between 1 and 2. Its control method is as follows:

When K ₁ is closed and K ₂ , K ₃ , and K ₄ are open, 1-2 outputs a full-wave rectified waveform. When the power frequency is a positive half-wave, D ₁ and D ₄ are connected to the circuit, and the current direction is: AC—>D ₁ —> Test sample —> D ₄ —>AC; when the power frequency is negative half-wave, D ₂ and D ₃ are connected to the circuit, and the current direction is: AC —> D ₂ —> Test sample —> D ₃ —> AC.

When K ₁ and K ₄ are closed, and K ₂ and K ₃ are disconnected, 1-2 outputs a DC waveform, and the working state of the silicon rectifier stack is the same as that of full-wave rectification, except that the filter capacitor C is connected to the output end of the circuit.

When K ₂ is closed and K ₁ , K ₃ , and K ₄ are disconnected, 1-2 outputs a half-wave rectified waveform. When the power frequency is a positive half-wave, only D ₁ is connected to the circuit, and the current direction is: AC—>D ₁ —> Test sample under test -> AC.

When K ₂ and K ₃ are closed and K ₁ and K ₄ are disconnected, 1-2 outputs a power frequency waveform, and the silicon rectifier stack and filter capacitor do not work.

As shown in Figure 3, the back-to-back analog device can be obtained from the prior art, and it outputs a maximum of 9 voltage signals, and different voltage signals are provided to the oven according to a certain combination. The AC voltage is applied to the voltage regulator and converter transformer of the back-to-back simulation device, and the converter valve groups on the rectification side and inverter side output different voltage signal waveforms at different points. Among them: points A and L lead to the continuous operation voltage signal of the analog valve arrester; points B and K lead to the continuous operation voltage signal of the analog DC midpoint bus arrester; points D and F lead to the continuous operation voltage signal of the analog converter DC bus arrester ; Points C and G lead to superimposed commutation overlapping angle waveform signals on the power frequency waveform; point E leads to the continuous operation voltage signal of the simulated DC bus arrester.

The invention comprehensively simulates the complexity and diversity of the surge arrester's operating voltage, and has outstanding significance for proposing a unified standard for the accelerated aging test of the DC arrester.

Claims (2)

1. A multi-waveform aging test device for arrester, which includes multiple ovens, various waveform generators, back-to-back simulation devices and measurement and control systems, characterized in that: multiple voltage signals sent by various waveform generators and back-to-back simulation devices The high-voltage lead cable is introduced into the oven; the voltage divider and the sampling resistor are installed outside the oven, the voltage divider is connected in parallel to the two ends of the test sample in the oven through the cable, and the sampling resistor is connected in series with the test sample in the oven; the measurement and control system uses the acquisition card to collect data respectively. Current and voltage waveforms across the sense resistor and voltage divider. 2. A multi-waveform aging test device for lightning arresters according to claim 1, characterized in that: the switching between different waveforms of the AC and DC signal waveforms output by the multi-waveform generator is controlled by a switch.

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