The Research And Realization Of Modulation Technology For The High Voltage Inverter

With the rapid development of the economy, it brings huge energy consumption in earth’s resource, at the same time, increasing lack of green energy, people pay more attention to the development and design utilization of energy efficient products, has become a growing concerned research topic. High-voltage inverter in high speed power AC motor control system played the energy-saving effect, but with the traditional motor operating performance, compared to a big improvement. As the rapid process of power electronic technology, the traditional basic math research deeply and the wide application of advanced artificial intelligence, the high-voltage inverter modulation is an important research element of the high-voltage inverter.The staircase modulation technology and SPWM modulation technology are studied in this paper. Considering the staircase can be controlled in fundamental frequency, the switch loss can be effectively reduced, at the same time, the device’s voltage pressure standard, through the reasonable combination of switch angles, the superposition of square wave can be a very good offset for the high content of low harmonic, this control method can be obviously improve the waveform quality. In the course of the study, the mathematical model of harmonic elimination method is a set of extremely complex nonlinear multi-objective equations, there is still no mature solution method, so the staircase modulation technology is difficult to meet the real-time requirement of the actual usage.SPWM modulation technology is through the sine modulation signal compared with the triangle carrier signal, to generate a series of different width pulse, according to the principle of equal impulse, to get the approximate sine wave. This paper analysis of the commonly used control algorithms for the cascade inverter with high-voltage, made a comparative analysis of the output voltage waveform for the three sampling method, take an analysis of carrier phase shifting SPWM technology. Based on these analysis, principle of triangle carrier amplitude modulation equivalent with sinusoidal modulator amplitude modulation, and principle of sinusoidal modulator phase-shifting equivalent with the triangle carrier phase-shifting are proposed, using time-division multiplexed access to reduce the use of hardware resources to generate a multi-channel SPWM signal, then combined with the carrier phase shifting SPWM technology, designed the multi-channel SPWM generator based on FPGA, and carried out the application test.