DSP-based implementation of a simple space vector pulse width modulation algorithm for three-level NPC inverter

With the development of power semiconductor and digital processor technology, the design and application of three-level inverter in electric multiple units(EMU) are more and more extensive. The traditional space vector pulse width modulation (SVPWM) method for the three-level inverter requires estimating the sectors and calculating a lot of trigonometric functions. As a result, the calculation of SVPWM method for microprocessor is very complicated and large. To reduce the calculation working of the PWM module, a SVPWM method based on 60° coordinate system for three-level inverter is focused and discussed in this paper. Finally, a vector control system of asynchronous motor based on DSP was built up to verify the feasibility of this SVPWM method in this paper. Experimental results show that the adopted method can omit a lot of trigonometric functions, and reduce the calculating burden of the control system.