It is one of the main development trends of offshore wind power system to develop a DC wind farm consisting of a DC wind turbine (DCWT) in order to realize DC collection and DC transmission in wind energy. In order to reach functions of DCWT in high-voltage insulation isolation, bidirectional energy flow and DC short-circuit fault self-cleaning, a new DCWT topology suitable for series-connected wind farms is proposed. Adopting a DC/DC converter with H-bridge structure in place of the traditional isolated DC/DC converter, DCWT directly connected in series and modulated can realize the conversion from low-voltage DC to high-voltage DC. Based on PSCAD/EMTDC, the simulation model of DCWT series-connected wind farm is built. Through the simulation of the DCWT of the wind system under steady-state operation conditions such as balanced output power, unbalanced output power, voltage fluctuation of high-voltage DC bus, and fault operation conditions such as dynamic cut-in and cut-out of faulted DCWT, it verifies the output characteristics of the DCWT, the operational characteristics of the system, and the processing capacity of the system for fault DCWT. This improves the operational reliability and flexibility of DCWT, and provides a practical solution plan for the construction of a DC wind farm. This work is supported by the National Key Research and Development Program of China (No. 2021YFB1507005).