Fast development of a DSP-based control of three-phase four-leg inverter for auxiliary power supply converters using hardware-in-the-loop

This paper presents an easy and relatively fast way to design and implement control system of three-phase four-leg inverter in DSP (digital signal processor). The inverter model is emulated using hardware-in-the-loop simulator and control system is coded in TI DSP identical to the target system using graphically based block-diagram programming environment. A multi-loop cascade control is applied and two control strategies are implemented: i) the PI (proportional-integral) controllers with symmetrical sequence current and voltage decomposition and ii) the PIR (proportional-integral-resonant) controllers. Experimental results with symmetrical and single-phase loads are presented. The control algorithms are evaluated based on the execution time. Results show that PIR based control executes roughly three times fasted that PI control.