阅读说明：本技术 基于电流积分的直流高压设备绝缘材料累积电荷测量方法 (Current integration-based method for measuring accumulated charges of insulating materials of direct-current high-voltage equipment ) 是由 李岩 赵信华 程远 孙运涛 杨栋 刘锦泉 颜延利 周庆 李进 赵仁勇 杜伯学 于 2020-06-03 设计创作，主要内容包括：本发明公开了一种基于电流积分的直流高压设备绝缘材料累积电荷测量方法,涉及高电压设备中绝缘材料的质量控制和状态评估领域,包括测量系统、高压电源、待测设备、封装外壳以及PC机,所述测量系统封装于封装外壳内部,所述测量系统包括积分电容器、阻抗变换器、模数(AD)转换器以及发射器,本发明将积分电容器插在高压端子和检测目标之间,对流过积分电容器的电流进行积分进而达到测量检测目标电荷累积量的目的,提高直流高压设备运行的稳定性和电力系统的安全性。(The invention discloses a method for measuring accumulated charges of an insulating material of direct-current high-voltage equipment based on current integration, which relates to the field of quality control and state evaluation of the insulating material in the high-voltage equipment, and comprises a measuring system, a high-voltage power supply, equipment to be measured, a packaging shell and a PC (personal computer), wherein the measuring system is packaged in the packaging shell and comprises an integrating capacitor, an impedance converter, an analog-to-digital (AD) converter and a transmitter.)

1. A method for measuring the accumulated charge of an insulating material of direct current high-voltage equipment based on current integration,the device is characterized by comprising a measuring system, a high-voltage power supply, equipment to be measured, a packaging shell (5) and a PC (personal computer), wherein the measuring system is packaged in the packaging shell (5), the measuring system comprises an integrating capacitor (1), an impedance converter (2), an analog-to-digital (AD) converter (3) and a transmitter (4), and the integrating capacitor (1) is inserted between a high-voltage terminal and a detection target; an impedance converter (2) converts the obtained Q (t) into an analog output voltage V which is not affected by external noise_Q(t)(ii) a The analog-to-digital converter (3) outputs an analog output voltage V_Q(t)Conversion to digital voltage V_D(t)(ii) a The transmitter (4) converts the digital voltage V_D(t)Transmitting the signal to a PC;

measurement of the amount of charge accumulation: applying different voltages for each measurement, then integrating the current I (t) flowing through the high-voltage circuit, and calculating the accumulated charge Q (t) in the sample;

the obtained Q (t) is converted into a stable voltage V which is not influenced by external noise through an impedance converter (operational amplifier)_Q(t)；

Analog output voltage V_Q(t) conversion to a digital voltage V by an A-D converter_D(t) of (d). Then, V_D(t) is transmitted to the transmitter;

finally, the collected signals are transmitted to a receiving unit connected to a PC.

2. A method for measuring accumulated charges in insulating materials of high voltage dc equipment based on current integration according to claim 1, wherein the integrating capacitor (1) is inserted between the high voltage terminal and the target to be detected, so that the current flowing through the capacitor and the target to be detected is the same.

3. Method for measuring accumulated charges in insulating materials of direct current high voltage equipment based on current integration according to claim 1, characterized in that the impedance converter (2) converts the accumulated charges q (t) obtained by the integration capacitor (1) into a stable voltage V (t) that is not affected by external noise_Q(t)。

4. Direct current high voltage device insulation material accumulator based on current integration according to claim 1Method for measuring the accumulated charge, characterized in that the analog-to-digital (AD) converter (3) converts an analog output voltage V_Q(t)Conversion to digital voltage V_D(t)。

5. Method for measuring the accumulated charge of an insulating material of a direct current high voltage device based on current integration according to claim 1, characterized in that the transmitter (4) applies a digital voltage V_D(t)The signal is transmitted to the PC.

Technical Field

The invention belongs to the field of quality control and state evaluation of insulating materials in high-voltage equipment, and relates to a method for measuring accumulated charges of insulating materials of direct-current high-voltage equipment based on current integration, which is mainly applied to measurement of the accumulated charges of the direct-current high-voltage equipment and improves the running stability of the direct-current high-voltage equipment and the safety of an electric power system.

Background

With the rapid development of power electronic technology, computer technology and control theory, the development of direct current transmission and distribution systems has made great progress in modern power grids and energy internet. Compared with the traditional alternating current transmission, the direct current transmission is applied to the aspects of long-distance high-capacity overhead transmission lines, submarine cable transmission, alternating current system interconnection and the like, and has very outstanding advantages in economic benefit and rapid controllability. The voltage class of the dc high voltage equipment is also continuously increased, and people put more severe requirements on the performance of the insulating material of the dc high voltage equipment.

It is generally believed that the aging of the insulating medium is inseparable from the charge transport, and that the trap distribution is believed to affect charge accumulation, dissipation, transport characteristics. In the process of using the insulating material of the direct current high-voltage equipment, charge accumulation can be gradually generated to cause insulation aging, so an effective measurement method is adopted to obtain the accumulated charge, and whether insulation is aged or not is judged according to the accumulated charge.

The integration capacitor is inserted between the high-voltage terminal and the detection target, when voltage is applied, the same current flows through the integration capacitor and the test sample, the current is integrated to obtain the charge accumulated in the test sample, and the method has the advantages of simplicity and convenience in operation, accuracy in measurement and the like, and provides a new method for measuring the charge accumulated in the insulating material of the direct-current high-voltage equipment.

Disclosure of Invention

The invention aims to provide a method for measuring the accumulated charge of an insulating material of direct-current high-voltage equipment based on current integration, which is used for measuring the charge accumulated in the direct-current high-voltage equipment.

In order to achieve the purpose, the invention provides the following technical scheme: the direct-current high-voltage equipment insulating material accumulated charge measuring method based on current integration comprises a measuring system, a high-voltage power supply, equipment to be measured, a packaging shell and a PC (personal computer), wherein the measuring system is packaged in the packaging shell and comprises an integrating capacitor, an impedance converter, an analog-to-digital (AD) converter and a transmitter (4), and the integrating capacitor is inserted between a high-voltage terminal and a detection target; the impedance converter converts the obtained Q (t) into a stable voltage V which is not affected by external noise_Q(t)(ii) a Analog-to-digital (AD) converter converts an analog output voltage V_Q(t)Conversion to digital voltage V_D(t)(ii) a The transmitter converts the digital voltage V_D(t)Transmitting the signal to a PC;

measurement of the amount of charge accumulation: applying different voltages for each measurement, and then integrating the current I (t) flowing through the high-voltage circuit to calculate the accumulated charge Q (t) in the sample;

the obtained Q (t) is converted into a stable voltage V which is not influenced by external noise through an impedance converter (operational amplifier)_Q(t) of (d). Analog output voltage V_Q(t) conversion to a digital voltage V by an A-D converter_D(t) of (d). Then, V_D(t) is transmitted to the transmitter. Finally, the collected signals are transmitted to a receiving unit connected to a PC.

As a further scheme of the invention: the integration capacitor is inserted between the high-voltage terminal and the detection target so that the currents flowing through the capacitor and the detection target are the same.

As a further scheme of the invention: the impedance converter converts the accumulated charge Q (t) obtained by the integrating capacitor into a stable voltage V which is not influenced by external noise_Q(t)。

As a further scheme of the invention: the analog-to-digital (AD) converter converts an analog output voltage V_Q(t)Conversion to digital voltage V_D(t)。

As a further scheme of the invention: the transmitter converts the digital voltage V_D(t)The signal is transmitted to the PC.

Compared with the prior art, the invention has the beneficial effects that: the invention inserts the integrating capacitor between the high-voltage terminal and the detection target, and integrates the current flowing through the integrating capacitor to further achieve the purpose of measuring the charge accumulation amount of the detection target. Therefore, the method has important theoretical value and engineering significance for improving the running stability of the direct-current high-voltage equipment and the safety of the power system.

Drawings

Fig. 1 is a basic circuit diagram of measurement of accumulated charge in an insulating material of a dc high voltage device based on current integration.

Fig. 2 is a measurement setup diagram of the measurement of the accumulated charge in the insulation material of a dc high voltage device based on current integration.

Fig. 3 is a graph of accumulated charge versus time and voltage.

In the figure: 1-integrating capacitor, 2-impedance converter, 3-analog-to-digital (AD) converter, 4-transmitter and 5-packaging shell.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.