Analysis and comparison of current-source-converter-based medium-voltage PMSG wind energy conversion systems

CSC topology with natural advantages in terms of simple structure, grid friendly waveforms, controllable power factor, and reliable grid short-circuit protection is considered to be a promising converter configuration for use in mediumvoltage (kV) high-power (MW) PMSG based wind energy systems. In view of this, three types of configurations for current source converter (CSC) based medium-voltage PMSG wind energy conversion system (WECS) are investigated, analyzed and compared in this paper. The advantages and disadvantages of these configurations are illustrated. And detailed control scheme for each configuration is analyzed and conducted. Comparisons are carried out based on analysis and simulation results in terms of converter cost, operation range, generator-side current THD, maximum power point tracking (MPPT), dynamic performance, and number of control freedoms. Among all, the back-to-back pulse-width modulated (PWM) current source converter is considered to be the most promising converter. Additionally, it is further illustrated that the DC-current value determined by both generator-side and grid-side can ensure a full operation range under all operation conditions.