Portable resistive leakage current detection device of arrester

Abstract

The invention discloses a portable resistive leakage current detection device of an arrester. The portable resistive leakage current detection device comprises a measurement device and a handheld receiver, wherein the measurement device and the handheld receiver are connected through wireless communication; the measurement device comprises a measurement circuit; the measurement circuit comprises a current transformer circuit, a coupling voltage phase collection circuit, a signal processing circuit, a measurement device power supply circuit, a measurement device switching circuit, a measurement device microprocessor circuit, an alarm circuit, a work indication circuit and a measurement terminal radio frequency circuit; and the input end of the current transformer circuit is connected with an upper-end current measurement line and a lower-end current measurement line separately. A phase signal of voltage of a working transmission line of the arrester is obtained by using a capacitance effect formed between a copper-clad plate and a transmission line conductor in an electric field coupling non-contact manner, so that the phase signal of the working voltage of the arrester can be obtained simply and feasibly.

Description

technical field [0001] The invention relates to a detection device for a resistive leakage current of a lightning arrester, in particular to a detection device for a portable resistance leakage current of a lightning arrester. Background technique [0002] In terms of arrester performance testing, there are many researches at home and abroad. At present, the detection methods of gapless oxide arrester (MOA) mainly include periodic power failure prevention test and online live test and detection. [0003] The periodic preventive test is generally carried out in the state of power failure, and it is the earliest and most common detection method used in the power system. At present, for the periodic preventive test, the main test item is the DC test, which measures the leakage current of the surge arrester under the critical action reference voltage U1mA of DC 1mA and 75% of U1mA. Through the test, it can be checked whether the valve plate is damp and whether the action perform...

AI Technical Summary

Problems solved by technology

There are two main common problems in these two methods: 1) The wired detection method is used, the dragging line is long, the operation is very inconvenient, and the high-voltage operation has certain dangers; 2) The voltage reference signal comes from the secondary side of the PT of the phase under test , which is an indirect acquisition signal, the parameters are easy to be distorted and cause errors, and sometimes the distance between the arrester and the substation is far away and the voltage signal cannot be obtained

However, the heating of MOA largely depends on the voltage distribution during operation. When the phase voltage changes by 5%, the energy loss of MOA can reach 20%, which directly causes the temperature of MOA to change by 1 to 2 degrees, and is easily affected by external interference.

[0009] The above two methods are based on the principle of temperature detection, and the main problems are: 1) It is necessary to place a sensor inside the arrester. Due to the limitation of the operation mode, it cannot be widely used for the MOA that has been put into safe operation of the power grid; 2) The temperature signal is easily affected. External influence is not conducive to the accuracy of detection; 3) There is no unified standard for current methods, and the accurate diagnosis of MOA largely depends on field experience

[0010] To sum up, the currently recognized effective detection method for the performance of oxide arresters at home and abroad is to use the wired method to obtain voltage signals from the PT line and use the resistive current method or phase angle difference method to detect, but in practice, the installation position of most arresters is far from the substation. Far, it is difficult to obtain the voltage signal, so it is impossible to directly use the resistive current method or the phase angle difference method to detect the performance of the arrester

[0011] Because the resistive current method or the phase angle difference method is used directly to detect the performance of the arrester, it is necessary to obtain the voltage phase signal, and the voltage phase signal cannot be obtained directly from the high-voltage line, which brings difficulties to the performance of the arrester using the traditional detection method.

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