一种具有自黑启动和故障穿越能力的新型经济型高压直流系统

This paper proposes a promising alternative for cost- effective high voltage direct current (HVDC) system that can realize the black start of offshore wind power plants (WPPs), active voltage build-up and harmonic suppression at the point of common coupling, AC fault ride-through and DC fault ride- through. A featured improvement is that the DC voltage reversal of the current source converter is fully explored and introduced into the offshore rectifier station (RS), based on which a special negative feedback is designed into the power circuit stage so that the short-circuit current under DC faults can be actively suppressed even in the absence of controls and protections. Comparing with the classic HVDC systems, the proposed system inherits the low-cost feature of the diode rectifier based HVDC system, but can remove the start-up cables and passive filters, and improve the performance under AC and DC faults. Finally, the feasibility of the analysis is demonstrated by simulation results.