Real-Time Implementation of a Hybrid Protection Scheme for Bipolar HVDC Line Using FPGA

A hybrid protection scheme for bipolar HVDC line has been implemented with field-programmable gate array (FPGA) and evaluation of its performance in real time is described in this paper. The protection scheme amalgamates a traveling wave protection unit, a boundary protection unit, and a lightning unit. A stationary wavelet transform (SWT) and its wavelet modulus maxima are used to remove noise and represent a useful traveling wave signal. Boundary protection based on SWT is used jointly with traveling wave protection to distinguish internal faults from external faults. The lightning unit is used to distinguish non-fault transients and to identify the faulty pole. Xilinx XtremeDSP Development Kit-4 is employed for the hardware implementation, with coding done using the Xilinx System Generator and AccelDSP. The cost-efficient hardware co-simulation approach is adopted here to evaluate the real-time performance of the protection scheme.