System and method for damping oscillations in power systems

A battery energy storage system, comprising:

• a power conversion system, configured to convert between a direct current power and an alternating current power;
• a battery core including an array of battery cubes, configured to provide the direct current power to the power conversion system;
• a point of connection, configured to couple the power conversion system to an electrical grid and exchange the alternating current power between the electrical grid and the power conversion system;
• a meter, configured to measure an active power sub-controller measured value of the alternating current power and a reactive power sub-controller measured value of the alternating current power at the point of connection;
• and
• a power oscillation damping controller, configured to provide an active power component adjustment that configures or results in an evident dampening of a power oscillation of the active power sub-controller measured value, the active power component adjustment calculated based upon the active power sub-controller measured value, and a reactive power component adjustment that configures or results in an alternative dampening of the power oscillation of the active power sub-controller measured value, the reactive power component adjustment calculated based upon the reactive power sub-controller measured value,
• the power oscillation dampening controller being configured to compute a target active power value by adding the active power component adjustment that configures or results in the evident dampening of the power oscillation to a reference active power dispatch value, and compute a target reactive power value by adding the reactive power component adjustment that configures or results in the alternative dampening of the power oscillation to a reference reactive power value;
• and
• the power oscillation dampening controller being configured to output the target active power value and the target reactive power value to a power plant controller for mitigating power drift.

A power oscillation damping controller comprising:

• a processor;
• a memory accessible to the processor and programmed to configure the power oscillation damping controller to:
• receive an active power sub-controller measured value including an evident oscillation component of a power oscillation;
• receive a reactive power sub-controller measured value including an alternative oscillation component of the power oscillation;
• calculate, based on the evident oscillation component of the active power sub-controller measured value, an active power component adjustment that configures or results in an evident dampening of the power oscillation;
• calculate, based on the alternative oscillation component of the reactive power sub-controller measured value, a reactive power component adjustment that configures or results in an alternative dampening of the power oscillation;
• compute a target active power value by adding the active power component adjustment that configures or results in the evident dampening of the power oscillation to a reference active power dispatch value;
• compute a target reactive power value by adding the reactive power component adjustment that configures or results in the alternative dampening of the power oscillation to a reference reactive power dispatch value;
• and
• output the target active power value and the target reactive power value to a power plant controller for mitigating power drift.