High Voltage Direct Current (HVDC) Technology has been widely recognized advanced in power transmission. Classical HVDC has shown its advanced features in long distance bulk power delivery, submarine cable crossings, and asynchronous interconnections. Therefore, the new generation of technology, embedded HVDC, is further broadening the range of applications of HVDC transmission. The embedded HVDC is beneficial to all traditional occupations. Meanwhile, perspective novel applications, which are involved in offshore transmissions, infeed large urban areas, DC segment grid, and weak AC system connections, come into service. The installation of the embedded HVDC systems on the existing AC power grid may largely improve the transient stability and power flow oscillation damping factor of power transmission system.