Application of Z-source sparse matrix converter for microturbine generators

This paper presents a Z-source inverter control strategy for controlling a micro-turbine in autonomous mode. Traditional topologies like back to back PWM converter have some considerable dilemmas such as problems related to usage of bulky DC-link. Matrix converter has been proposed to overcome the problems. But it has some disadvantages such as maximum transfer ratio of 0.86. Here, a z-source sparse matrix converter is proposed to overcome some problems of conventional matrix converter. Reduction of the number of unipolar turn-off power semiconductors, solving the inherent drawback of the low voltage transfer ratio and simple switching strategy are some advantages of the proposed topology. Microturbine dynamic modeling and the proposed converter as well as its controller are introduced in details. A simulation of the overall system is carried out by MATLAB/Simulink. The simulation results show that contrary to matrix converter, the proposed topology can achieve suitable range of voltage transfer ratio and regulates the output voltage in step load variation and disturbance conditions. In addition to mentioned advantages the proposed converter facilitates to employ battery storage for starting up the microturbine and reduce the mutual impact between both sides.