Pulse harmonic signal direct current transformer error detection device and calibration method thereof

Abstract

The invention provides a pulse harmonic signal direct current transformer error detection device. The device comprises a direct current and pulse harmonic current output module and an external detected input module, wherein the direct current and pulse harmonic current output module outputs direct current and direct current superposition pulse harmonic current to an internal sampling circuit and a self-calibration standard resistor array; the internal sampling circuit converts the input direct current and direct current superposition pulse harmonic current into voltage signals, and sends the voltage signals to an AD sampling measurer through a front-end conditioning circuit and a detected input channel. According to the error detection device, a standard resistor array with high accuracy, good long-term stability and small inductive reactance is used as a traceability standard, accuracy of a direct-current transformer and a direct-current amplifier under direct-current and direct-current superposed pulsation harmonic signals is detected, and self-calibration of direct-current and pulsation harmonic signal measurement is completed on a test site.

Description

technical field [0001] The invention relates to the technical field of DC power transmission, in particular to a device for detecting errors of DC transformers with pulsating harmonic signals and a calibration method thereof. Background technique [0002] The DC transformer and its DC signal amplifier in the converter station are important secondary measurement equipment for the DC transmission system. Provide key information and data for the control, protection and measurement of power transmission system. The accurate and reliable operation of the equipment is directly related to the safe and stable operation of the entire DC transmission system. The accuracy and reliability of DC transformers and DC amplifiers requires a DC transformer error detection device with standard values ​​for on-site detection and error calibration. Therefore, the DC transformer error verification device is the key equipment for detecting the errors of DC transformers and DC amplifiers. The DC ...

AI Technical Summary

Problems solved by technology

Therefore, the DC transformer error verification device is the key equipment for detecting the errors of DC transformers and DC amplifiers. The DC transformer error detection device needs to be verified and calibrated by relevant institutions before the errors of other DC transformers can be verified; however, in order to reduce radiation The impact on the surrounding residents is generally built in remote areas. Therefore, for the detection of DC transformers and DC amplifiers in the converter station, the detection staff must carry the DC transformer error detection device to the site to detect the DC transformers and DC amplifiers in the converter station. , the transformer error verification device has undergone long-distance transportation and bumpy mountain roads, and its accuracy is difficult to guarantee strictly; at the same time, when testing the transformer, once abnormal conditions such as overcurrent, overvoltage, and abnormal wiring occur, the error detection of the DC transformer may The accuracy of the device is affected, and its accuracy cannot be strictly guaranteed. It needs to be verified and calibrated by the verification institution again, and the distance from the calibration institution is far away, so it cannot be verified and calibrated again in a short time, thus causing the inspectors to go back and forth for several days. stations and testing agencies, resulting in a great waste of manpower and time; and, in the prior art, when verifying the error detection device of the DC transformer, the DC calibration is often performed through the DC source plus the DC standard transformer, and the AC source plus the AC standard transformer. For the pulsating harmonic signal above 50Hz to 1.2KHz, additional equipment calibration is required. Although there are high-precision and wide-range AC and DC current high-precision shunts abroad, they are expensive, and relevant institutions or manufacturers may not be able to purchase them. , so the verification operation process of the existing technology is complicated, and the requirements for the verification personnel are high, and the verification results may need to be tested repeatedly, resulting in a great waste of manpower and time. It operates under signal conditions, so the verification should be consistent with the actual situation, and it also needs to be detected under the DC superimposed pulsating harmonic signal, and the existing technology lacks corresponding verification methods for DC transformers and DC amplifier error detection devices

Images