CN101696988A - Monitor for three-section type lightning arrester - Google Patents

Abstract

A monitor for three-stage arresters, especially suitable for UHV arresters, including a current monitoring device and three counting devices. The current monitoring device is composed of a protection circuit and an ammeter, and the three counting devices are composed of sampling resistors, bridge rectifier circuits, energy storage capacitors, and counter coils, but the types and specifications of the energy storage capacitors and counter coils of the three counting devices are different. Same. The invention can monitor the magnitude of the current flowing through the arrester, and the three counting devices can respectively display the operation times of the arrester after the overvoltage flows through the arrester under different waveforms and energies, so as to better judge the operation of the arrester.

Description

Monitor for three-stage arrester

technical field

The invention relates to a monitor for a three-stage lightning arrester, which is especially suitable for monitoring the current and various overvoltage times of an ultra-high voltage arrester.

Background technique

According to the Jindongnan-Jingmen 1000 kV UHV AC Test Demonstration Project 1000 kV Porcelain Jacketed Metal Oxide Surge Arrester Technical Agreement, the UHV metal oxide surge arrester must be equipped with a monitor, and the installed monitor must have two functions. One: Monitor the current flowing through the arrester. Second: Monitor the number of arrester actions. Judging from the operation of the arrester monitors in the 1000 kV UHV AC test base, the base has carried out 4 times of 1000kV transformer switching. In the same switching process, the number of actions of the 4 types of 6-phase monitors is different. In a switching process Among them, some move once, some move twice, some don't move, and some move several times, dozens of times or even hundreds of times. If this situation occurs in formal engineering, it will be very unfavorable for operation monitoring and analysis, and it is necessary to study this and propose solutions.

Contents of the invention

In view of this, the object of the present invention is to provide a monitor for a three-stage arrester, which provides a monitor that can monitor the current flowing through the arrester, and can record the number of times that the overvoltages of different waveforms and energies flow through the arrester, Provide good data support for the correct monitoring of the operation of the arrester.

The technical scheme of the present invention is: a monitor for three-stage lightning arrester, including a current monitoring device, characterized in that it also includes three counting devices, and the relationship between each device is: the current monitoring device and the counting device are connected in parallel with the lightning arrester Connection, the current monitoring device is composed of a protection circuit and an ammeter connected in parallel, the counting device is composed of three counting circuits in series, the first counting circuit is composed of a rectifier circuit, resistor R1, capacitor C1 and counter coil L1, resistor R1 and rectifier In parallel, the rectifier circuit is connected to the capacitor C1, and the capacitor C1 is connected to the counter coil L1; the second counting circuit is composed of the rectifier circuit, the resistor R2, the capacitor C2 and the counter coil L2, the resistor R2 is connected in parallel with the rectifier circuit, and the rectifier circuit is connected to the capacitor C2, The capacitor C2 is connected to the counter coil L2; the third counting circuit is composed of a rectifier circuit, a resistor R3, a capacitor C3 and a counter coil L3, the resistor R3 is connected in parallel with the rectifier circuit, the rectifier circuit is connected to the capacitor C3, and the capacitor C3 is connected to the counter coil L3.

The above-mentioned three-stage lightning arrester monitor is characterized in that: the three sampling resistors R1, R2, R3 are of the same type, its technical index is 10kA, and the residual voltage is 1450V.

The above-mentioned three-stage arrester monitor is characterized in that: the capacitance of the three capacitors C1, C2, and C3 is 10 μf, and the rated voltage is 630V.

The above three-stage arrester monitor is characterized in that the operating voltage of the counter coil L1 is 12V, the operating voltage of the counter coil L2 is 24V, and the operating voltage of the counter coil L3 is 36V.

The beneficial effect of the present invention is that the magnitude of the current flowing through the arrester can be monitored, and the three counting devices can respectively display the operation times of the arrester after the overvoltage flows through the arrester under different waveforms and energies, so as to better judge the operation of the arrester .

Description of drawings

Fig. 1 is a principle structural diagram of the present invention.

Detailed ways

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

Marking description in Fig. 1: 1-rectification circuit, 2-rectification circuit, 3-rectification circuit.

As shown in Figure 1, the current monitoring device is composed of a protection circuit and an ammeter. The function of the protection circuit is to protect the voltage applied to both ends of the ammeter from being less than the allowable value of the ammeter. The first counting circuit is composed of a resistor R1, a rectifier circuit 1, a capacitor C1, and a counter coil L1. The voltage signal obtained through the resistor R1 passes through the rectifier circuit 1 to charge the capacitor C1. After the charging is completed, the counter coil L1 discharges to achieve the counting function; the second counting circuit is composed of resistor R2, rectifier circuit 2, capacitor C2, and counter coil L2. The voltage signal obtained through resistor R2 passes through rectifier circuit 2 to charge capacitor C2 , after the charging is completed, the counter coil L2 is discharged to achieve the counting function; the third counting circuit is composed of a resistor R3, a rectifier circuit 3, a capacitor C3, and a counter coil L3. The voltage signal obtained through the resistor R3 passes through the rectifier circuit After 3, the capacitor C3 is charged, and after the charging is completed, the counter coil L3 is discharged to achieve the counting function.

When there is an overvoltage flowing through the arrester, the arrester will flow a considerable current at this time, and the current will flow through the sampling resistors R1, R2 and R3. When the current flows through R1, if the voltage applied to both ends is too high, the protection circuit will limit the voltage to avoid burning out the ammeter. When the current is within the display range of the ammeter, the ammeter will correctly display the current flowing through R1, and also That is, the current flowing through the arrester.

Example 1: When the current flows through R1, a voltage signal will be generated on R1, which will become a DC voltage after passing through the rectifier circuit 1, and the capacitor C1 will be charged by the DC voltage, and the counter coil L1 will be discharged after the charging is completed. , to complete a count, so as to achieve the counting function.

Embodiment 2: When the current flows through R2, a voltage signal will be generated on R2, which will become a DC voltage after passing through the rectifier circuit 2, and the capacitor C2 will be charged by using the DC voltage. After the charging is completed, the counter coil L2 will be discharged , to complete a count, so as to achieve the counting function.

Embodiment 3: When the current flows through R3, a voltage signal will be generated on R3, which will become a DC voltage after passing through the rectifier circuit 3, and the capacitor C3 will be charged by using the DC voltage. After the charging is completed, the counter coil L3 will be discharged , to complete a count, so as to achieve the counting function.

Among them: (1) The function of the counter coil L1 is to record the number of times the overvoltage passes through the arrester under all waveforms and energy;

(2) The function of the counter coil L2 is to record the wave head time of 30 microseconds, the wave tail time of 80 microseconds, the waveform and energy of the current amplitude above 250A and the number of times the overvoltage passes through the arrester;

(3) The function of the counter coil L3 is to record the number of times the overvoltage passes through the arrester under the waveform and energy of the current amplitude above 10kA when the wave head time is 8 microseconds and the wave tail time is 20 microseconds.

Claims (4)

1. monitor for three-section type lightning arrester, comprise a current monitoring device, it is characterized in that: also comprise three counting assemblys, relation between each device is: be connected with lightning arrester after current monitoring device and the counting assembly parallel connection, current monitoring device is composed in parallel by holding circuit and reometer, counting assembly is composed in series by three counting circuits, first counting circuit is made up of rectification circuit, resistor disc R1, capacitor C 1 sum counter coil L1, resistor disc R1 is in parallel with rectification circuit, rectification circuit connects capacitor C 1, capacitor C 1 linkage counter coil L1; Second counting circuit is made up of rectification circuit, resistor disc R2, capacitor C 2 sum counter coil L2, and resistor disc R2 is in parallel with rectification circuit, and rectification circuit connects capacitor C 2, capacitor C 2 linkage counter coil L2; The 3rd counting circuit is made up of rectification circuit, resistor disc R3, capacitor C 3 sum counter coil L3, and resistor disc R3 is in parallel with rectification circuit, and rectification circuit connects capacitor C 3, capacitor C 3 linkage counter coil L3.

2. monitor for three-section type lightning arrester according to claim 1 is characterized in that: three sample resistance sheet R1, R2, R3 are that its technical indicator is 10kA with a kind of model, and residual voltage is 1450V.

3. monitor for three-section type lightning arrester according to claim 1 is characterized in that: the electric capacity of capacitor C 1, C2, three capacitors of C3 is 10 μ f, rated voltage 630V.

4. monitor for three-section type lightning arrester according to claim 1 is characterized in that: the operating voltage of counter coil L1 is 12V, and the operating voltage of counter coil L2 is 24V, and the operating voltage of counter coil L3 is 36V.

Images