Synchronous condenser (SC) has a fast reactive power response and extensive reactive power adjustment range, which is suitable for China HVDC transmission system that has a great demand for dynamic power support. However, when the steadystate reactive power output of the SC is large, its transient reactive power output will be limited. In order to make full use of the SC′s transient reactive power output capability and increase its transient reactive power margin, the SC is configured with static reactive power compensation devicescapacitors and reactors, which are different from filter banks in the HVDC converter station. In addition, the SC′s capacity configuration and coordinated control strategy with capacitors and reactors are proposed.Coordinated control makes the response frequency bands of two types of reactive power compensation devices different to make full use of the steadystate reactive power output capacity of capacitors and reactors and the SC′s transient reactive power supporting capability. Finally, the model of an HVDC transmission system with SCs is constructed on the PSCAD platform, and the effectiveness of the capacity configuration and coordinated control strategy is verified.