Grid-side winding alternating-current harmonic detection system based on converter transformer

Abstract

The invention discloses a grid-side winding alternating-current harmonic detection system based on a converter transformer. The system comprises a current harmonic measurement sensor installed outsidea grid side sleeve ascending flanged base, a voltage harmonic measurement sensor sleeving a parallel coupling capacitor grounding wire, a signal acquisition module, a voltage-stabilized power supplyand a portable computer. The current harmonic measurement sensor can obtain a current signal of a converter transformer winding. A voltage harmonic measurement sensor sleeving a coupling capacitor ground wire can obtain a converter transformer grid side winding voltage signal by detecting a ground current signal and calculating the ground current signal, the signal acquisition module is responsible for acquiring and transmitting the signals, and calculation software performs harmonic analysis on the signals. The alternating current harmonic detection system can detect the voltage and current harmonic content of the converter transformer grid side winding, is high in anti-electromagnetic interference capability, meets the requirement for synchronous acquisition of multiple signals, and hashigh real-time performance and accuracy.

Description

technical field [0001] The invention relates to the technical field of electric power systems, in particular to an AC harmonic detection system based on a grid side winding of a converter transformer. Background technique [0002] The basic requirement of the power system is to ensure safe and reliable power supply for power users, and whether the power quality is qualified is very important for the operation of the power grid. The converter transformer, which plays the core role of AC-DC conversion in the process of UHVDC transmission, bears the combined action of AC and DC voltages during operation, and contains a large number of high-order harmonic components in the load current. This high-order harmonic component It will cause harmonic leakage magnetic field and higher harmonic loss in the converter transformer. Under the joint action of high-order harmonics and fundamental wave losses, extremely uneven harmonic losses are generated inside each component of the converte...

AI Technical Summary

Problems solved by technology

However, the measurement of both PT and CT is based on the measurement of the power frequency component, and the measurement accuracy and accuracy of the harmonic component have not attracted enough attention. Whether the existing transformer is suitable for the measurement of broadband voltage and current is unclear. learned that

In addition, for the converter transformer, under the working condition of 12 pulses, the characteristic harmonics of the grid-side system are 12n±1 order, but in fact the 6n±1 (n is an odd number) harmonics are self-contained in the winding loop, which cannot be measured in the outer loop this time, so for the converter transformer, its harmonic characteristics cannot be grasped only by measuring the transformer

In addition, the current harmonic detection technology for power systems still has problems such as poor real-time performance, low efficiency, and large electromagnetic interference.

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