The present invention provides coordinated control methods of generator and SVC for improving power plant active power throughput and controller thereof. The method comprises: measuring the required input parameters for the generator and SVC control; judging the system topology and the control mode of SVC to determine the operation mode; and calculating the control reference based on the operation mode to control the generator and/or SVC. The proposed methods and coordinated controllers enable the SVC to share the required reactive power output of the power plant, convert the generator into “unity-power-factor-generator”, and therefore extend the active power output capability of the power plant.