Control Design Strategy to Enhance Fault Ride through Capability of VSC-HVDC Transmission System Interconnecting Offshore Wind Power Plant - (PPT)

摘要

For the integrated European energy market, HVDC transmission system has proven itself as an essential component. In AC submarine cable, reactive power is one of the major factor in limiting the active power transfer capability of a transmission system. On the other hand, DC cables does not have reactive power to impose limitation for transferring power, also VSC based HVDC system has a capability to established an electrical network which is an essential requirement for offshore electrical network. Converters in VSC based transmission system must not only behave as a grid in the offshore network but also must fulfill the onshore grid integration requirements. The presented research envisage the design and development of voltage source converter (VSC) control system for offshore wind power plant integrated with the grid. Converter control system is based on vector control scheme and designed in voltage synchronous rotating frame. Small signal stability analysis have been carried out to design the converter current, voltage and power control system. To enhance the fault ride through capability of the converter during onshore fault, active current reduction method based on reference AC bus voltage has been proposed in order to improve the transient during voltage recovery period.