CN203204141U - Verifying device of oxide arrester insulation online monitoring device - Google Patents

Abstract

The utility model relates to a verification device for insulation on-line monitoring equipment of an oxide lightning arrester, which comprises a control unit, a signal generation unit, a precision current unit, a reference precision voltage unit, and a voltage amplification unit. Under the action of the control unit, each signal generation module generates an independent standard sinusoidal signal with adjustable frequency, amplitude, and phase angle, which excites the precision current unit and reference precision voltage unit of the subsequent stage, thereby generating mutually independent current and voltage signals. By changing the frequency, amplitude and phase of the current signal and voltage signal, different full current, resistive current, capacitive current, reference voltage and harmonic signals can be output. The calibration device can be used to perform high-accuracy calibration on the main measurement functions of the oxide surge arrester insulation on-line monitoring equipment, that is, the measurement functions of full current, resistive current, capacitive current, reference voltage and harmonic components.

Description

An oxide surge arrester insulation on-line monitoring equipment calibration device

technical field

The utility model relates to a calibrating device for oxide lightning arrester insulation on-line monitoring equipment, which belongs to the field of calibration, verification and detection of electric power testing instruments. The utility model can be used for the main measurement function of the oxide lightning arrester insulation on-line monitoring equipment, that is, the full current , resistive current, capacitive current, reference voltage, harmonic component and other measurement functions are verified with high accuracy, and the generated standard voltage and current signals can be effectively traced to the source of the value.

Background technique

Oxide arresters are important equipment to ensure the safe operation of power systems. However, due to the harsh working environment of oxide arresters, they are prone to aging and other phenomena, so it is necessary to monitor oxide arresters in real time. In view of this situation, many domestic electric power testing instrument manufacturers have begun to develop and produce oxide arrester insulation on-line monitoring equipment. However, according to the survey, the quality of on-line monitoring equipment for oxide surge arrester insulation in the domestic market is uneven. Calibration of such testers and providing reliable calibration data to users have positive effects on improving the quality of on-line monitoring equipment for oxide surge arrester insulation. significance.

At present, there is no corresponding calibration device to effectively calibrate or verify the on-line monitoring equipment of oxide arrester insulation, and it is impossible to judge the quality of the measurement data of oxide arrester insulation on-line monitoring equipment. Therefore, it is urgent to design oxide arrester insulation with good traceability. The on-line monitoring equipment calibration device, that is, the highly accurate and traceable oxide arrester insulation on-line monitoring equipment calibration device, meets the urgent needs of the current calibration work.

Contents of the invention

The purpose of this utility model is to aim at the working principle of the existing on-line monitoring equipment for the insulation of oxide lightning arresters, taking into account the traceability of the calibration device, to provide a calibration device for the insulation of oxide lightning arrester on-line monitoring equipment, the accuracy of which can meet the requirements of calibration oxides Surge arrester insulation on-line monitoring equipment needs, and has good traceability. The core idea is: the verification device outputs voltage and current signals with accurate and controllable amplitude, frequency and phase. The verification device designed by the utility model can effectively verify the main measurement functions of the oxide lightning arrester insulation on-line monitoring equipment, that is, the measurement of full current, resistive current, capacitive current, reference voltage, and harmonic components.

In order to achieve the above purpose, the technical solution of the utility model provides a verification device for oxide lightning arrester insulation on-line monitoring equipment, including a control unit, a first signal generating unit, a second signal generating unit, a precision current unit, a reference precision voltage unit, a voltage The amplifying unit is characterized in that: the control signal output by the control unit is respectively input to the control terminals of the first and second signal generating units, the output of the first signal generating unit is connected to the input of the corresponding precision current unit, and the output of the second signal generating unit The input of the reference precision voltage unit is connected, the precision current unit outputs a current signal I, the output terminal of the reference precision voltage unit is connected with the input terminal of the voltage amplifying unit, and the voltage amplifying unit outputs a reference voltage U.

The verification device for oxide surge arrester insulation on-line monitoring equipment as described above is characterized in that the signal generation module adopts a circuit based on the chip AD421, and uses a DA chip to directly generate a sinusoidal signal with a stable and adjustable frequency, amplitude and phase and a smooth curve .

The verification device for oxide surge arrester insulation on-line monitoring equipment as described above is characterized in that the voltage amplifying unit includes an impedance matching circuit to adapt to oxide surge arrester insulation on-line monitoring equipment with different characteristic input impedances.

The beneficial effect of the utility model is that the main measurement functions of the oxide lightning arrester insulation online monitoring equipment, namely full current, resistive current, capacitive current, voltage and harmonic High-accuracy verification of measurement functions such as components, and the generated standard signals can be conveniently and effectively traced to the source of the quantity.

Description of drawings

Fig. 1 is a schematic diagram of an oxide surge arrester insulation on-line monitoring equipment verification device according to an embodiment of the present invention.

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples. Those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms are also within the scope of the claims listed in this application.

Marks in Figure 1: 1—control unit, 2, 4—signal generating unit, 3—precise current unit, 5—reference precision voltage unit, 6—voltage amplification unit, I —current, U —reference voltage.

Referring to FIG. 1 , it is a schematic diagram of a verification device for an oxide surge arrester insulation on-line monitoring device according to an embodiment of the present invention. The control signal output by the control unit is connected to the control terminals of the signal generation units 2 and 4, the output of the signal generation unit 2 is connected to the input of the corresponding precision current unit 3, and the output of the precision current unit 3 is current. The output of the signal generating unit 4 is connected to the input of the reference precision voltage unit 5 , the output of the reference precision voltage unit 5 is connected to the input of the voltage amplifying unit 6 , and the voltage amplifying unit 6 outputs the reference voltage U .

Its working principle is: under the control of the control unit 1 (specifically TMS320F2812), each signal generating unit 2, 4 (realized based on the chip AD421) can generate a smooth sine wave with independent frequency, amplitude and phase angle. Signal unit, these sinusoidal signals can excite the independent precision current unit 3, reference precision voltage unit 5, and voltage amplification unit 6 of the subsequent stage, thereby forming mutually independent current signal I and voltage signal U , by adjusting the current signal and voltage The frequency, amplitude and phase angle of the signal can simulate different full current, resistive current, capacitive current, reference voltage and harmonic component signals.

In this embodiment, the signal generating units 2 and 4 adopt the technology based on the AD421 chip to conveniently generate sinusoidal signals with stable and adjustable frequency, amplitude and phase, and smooth and stable curves.

The utility model has also adopted the following core technologies in design:

1. Standard sinusoidal signal generation module with adjustable frequency, phase and amplitude

In order to achieve the purpose of calibration, it is first necessary to generate basic standard sinusoidal signals, which will be used to excite the rear precision current unit and precision voltage unit and generate corresponding standard current signals and reference voltage signals. In order to obtain the standard sinusoidal signal with adjustable frequency, phase and amplitude, TMS320F2812 and 16-bit high-accuracy DA chip AD421 are adopted. Use DSP2812 to control AD421 output frequency, phase and amplitude stable and adjustable and smooth sinusoidal signal. Among them: the frequency of the sinusoidal signal can be very stable; the curve of the sinusoidal signal is very smooth, and no sawtooth can be seen at all with a conventional oscilloscope.

2. Oxide arrester insulation online monitoring equipment adapted to different voltage measurement principles by designing impedance matching circuits.

Since the voltage measurement line and the voltage measurement principle of the oxide arrester insulation online monitoring equipment are different, it is easy to cause the voltage output circuit to oscillate. Therefore, the utility model is specially designed for the voltage measurement principle and input impedance of the oxide arrester insulation online monitoring equipment. The matching circuit, through the impedance matching circuit, can greatly improve the load capacity of the voltage output unit of the calibration device for capacitive loads and inductive loads.

The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims (3)

1. A verification device for oxide surge arrester insulation on-line monitoring equipment, comprising a control unit, a first signal generating unit, a second signal generating unit, a precision current unit, a reference precision voltage unit, and a voltage amplification unit, characterized in that: controlled The unit output control signals are respectively input to the control terminals of the first and second signal generating units, the output of the first signal generating unit is connected to the input of the corresponding precision current unit, and the output of the second signal generating unit is connected to the input of the reference precision voltage unit. The current unit outputs a current signal I , the output terminal of the reference precision voltage unit is connected to the input terminal of the voltage amplifying unit, and the voltage amplifying unit outputs a reference voltage U . 2. The oxide surge arrester insulation on-line monitoring equipment verification device according to claim 1, characterized in that: the signal generation module adopts a circuit based on the chip AD421, directly generates frequency, amplitude and phase with the DA chip and is stable and adjustable and A sinusoidal signal with smooth curves. 3. The verification device for oxide arrester insulation on-line monitoring equipment according to claim 1, characterized in that: the voltage amplifying unit includes an impedance matching circuit to adapt to oxide arrester insulation on-line monitoring equipment with different characteristic input impedances.

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