Development Of Data Acqusition And Recording Unit Of Power Transient Signal Based On TMS320F2812

When the power system equipments are under handing over, repairing and working, in order to grasp the running state of the equipment, the electricity parameter are needed to measure, specially, the transient signal is the most important. In the aspect of fault analysis and transient protection of power system, most of methods are based on analysis of the electric power transient signal. Therefore, the acquisition and recording system of transient signal have to be developed.On the basic of analyzing the existing state of the acquisition and recording unit and studying the characteristics of TMS320F2812, the development of the acquisition and recording unit are determined.On the aspect of hardware circuit, it is made of five parts: DSP, A/D, power manage, signal adjustment and communication interface. The hardware board of first four parts have been completed. According to the request about acquisition and recording of electric power transient signal. TMS320F2812 will be as the main center processing unit, it will be charge of controlling each module of DSP and acquising transient signal. At the same time, the embedment A/D module is used to acquising the voltage and current. Bacuse of the higher acquisition speed, the data transmission speed between the recording unit and PC should be higher. Based on the high speed and easily taking of USB, it is chosen as the main transmission way. Besides, in order to make signal be suitable for acquisition, the range of current and voltage is transformed by the signal adjustment circuit.With regard to the software design, the traditional fast Fourier transformation(FFT) are used to analyze the harmonic of the voltage and current, and the power system parameters is also calculated. Considering the data quantity is large and timely request, the realization of algorithm processing is based on TMS320F2812 assembly command system. Besides, the main program uses the C language, which is advantageous for thereadability and transportability.With regard to the experiment, the part of A/D, data processing, data recording, UART and USB have been tested through the three-phase reference power source. The experiment indicates that the unit can work and satisfy the acquisition and recording of electric power transient signal.