Current Source Converters and Their Control

Abstract This chapter presents the applications and control of current source converters (CSCs). CSCs are among the first-generation power converters adopted in industry and have been widely adopted in high-power applications such as high-voltage direct current (HVDC) and high-power drives. For these high-power applications, the converter switching frequency is typically limited to a few hundred Hz or even lower, which leads to a challenge of converter output harmonics control and passive filter design. This chapter focuses on the design of grid-interfacing high-power CSCs with very low switching frequency and presents the recently proposed harmonics control strategy that not only reduces the harmonics produced by the converter but also mitigate harmonics introduced by the grid. The strategy includes virtual impedance control, selective harmonics compensation (SHC) method, and selective harmonic elimination (SHE) phase jittering technique. Experimental results of the above methods under polluted grid and harmonic resonance conditions are provided.