Hysteresis modulation-based sliding mode current control of Z-source DC-DC converter

The Z-source dc-dc converter is a boost-type converter with high voltage gain than conventional boost converter. However, like boost converter, the Z-source dc-dc converter is also a non-minimum phase system, it transfers energy to load indirectly via the Z-network inductors. This paper presents the hysteresis modulation-based control for Z-source converter. Using differential geometry it is proved that Z-source converter with load voltage as the output is a non-minimum phase system. The coordinate sliding function based on inductor current error ensures the stability of zero dynamics. With that proved, a sliding mode current control for Z-source dc-dc converter is proposed. The switching frequency of the converter is constrained by introducing a hysteresis band. The Matlab/Simulink is used for the system simulation and results are presented for the validation of proposed theoretical technique.