Research On Power Harmonic Detection System Based On DSP And CPLD

In recent years the rapid development of power electronic technology, power electronic communication equipment and nonlinear load are widely used in coal mine power network, caused serious harmonic pollution. Harmonic influence to the coal mine production system is becoming more and more serious, to the enterprise created a lot of economic loss. The management of mine power system harmonic is imperative technical problem, so first of all to the power system harmonic accurate online detection, and current harmonic detector or detection system generally only for inspection accuracy and developed, and can’t with control system together to harmonic real-time detection and inhibition, so to develop a can quickly detect the harmonic wave in the power grid, and the test results as the reference for the tracking control of harmonic detection system is very necessary.In order to real time accurate monitoring coal mine electric power system harmonic, accurately mastering the harmonic in mine situation in the grid, this paper developed a set of harmonic detection system, in view of the fast Fourier transform (FFT) spectrum leakage and existing problems such as fence effect, the add window bimodal line interpolation FFT algorithm for harmonic amplitude, phase and frequency correction and improve the precision of the algorithm. This system offered to TMS320F2812as a digital signal processor, the system increases the Complex Programmable Logic Device (CPLD) on the peripheral circuit Logic control, CPLD of programmability makes the system more flexible and easy to use, and the price is low. DSP+CPLD system design makes man-machine interface, data display more convenient. Application of the expansion of the high precision14external expanding AD converter MAX125, harmonic signal for high precision high-speed collection, through the system hardware and software design, realized the power to the three phase voltage and three phase current of the basic parameters of the real time measurement, through the liquid crystal display (LCD) on-line monitoring, and is convenient for measurement data for further analysis, statistics and storage. And the detection system and control system of combining a set of electric power harmonic on-line detection and real-time suppression device, the experimental results show that this system can realize to the power system voltage, current value and harmonic component parameters real-time accurate measurement, can satisfy the harmonic measurement standard. Application of the detection system prototype can realize power harmonic online testing, combined with control system achieves a good harmonic suppression effect.