DSP-based Analysis Of The Error Measurement For Electromagnetic Instrument Transformer

The main work of the instrumenttransformer in the grid is current andvoltagemeasurement, electric energy measuring and the supervision and protection for thepower system. These parameters are essential to the stable and economical operation ofthe power system. So the instrument transformer is indispensable for the system,especially its high accuracy. And the calibration of the instrument transformer is veryimportant.As the structure of the traditional transformer calibrator is complex and it is uneasy touse, this paper presents a new error measurement technology, which is based-on theDSP(Digital Signal Processor), to increase the system stability and measuring accuracy.Meanwhile, the efficiency of the calibration should be improved, too.This paper mainly focuses on the error analysis of the transformer and the design ofthe system. By comparing advantages and disadvantages of different CPU chips, the DSPis chosen to implement the scheduled function.The design and implement of the hardware and software of the measurement systemis introduced in detail. The design of analog hardware circuit and digital hardware circuitof the system is important and its EMC should also be concerned. After analyzing kinds ofsampling algorithms, the FFT (Fast Fourier Transform) algorithm is adapted to process thesignals. The measurement system programming ideas are introduced, main program flowchartsare provided, and design ideas of specific functions of the program are described.