A power generation system (10, 110, 210) comprising: a renewable power source (12, 112, 212) configured to produce a source power; a source side converter (32, 132, 232) configured to convert the source power to converted DC power; a source side controller (38, 138, 238) configured to drive the converted DC power towards a maximum power point; a DC link (34, 134): configured to receive the converted DC power; a grid side converter (36, 236) coupled to the DC link configured to convert DC link power from the DC link to AC output power for a grid; a grid side controller (40, 140, 240) configured to control the AC output power of the grid side converter to achieve grid interconnection requirements; an electrical energy storage device (42, 142); an energy storage converter (44, 144, 244) configured to couple the energy storage device to the DC link; an energy storage controller (46, 146) configured to control the energy storage converter to achieve a desired power balance on the DC link; and a state of charge SOC, manager configured to receive a SOC signal from the energy storage device (42, 142) and, if the SOC signal is below an acceptable SOC operating range, to provide a respective adjustment signal to the grid side controller (40, 140, 240) to reduce the output power from the grid side converter (36, 236), and/or to the source side controller (38, 138, 238) to increase the source side power so that some energy can be absorbed in the energy storage device (42, 142), and if the SOC is above the acceptable SOC operating range, to provide a grid control signal to the grid side controller (40, 140, 240) to increase the output power to the grid, to switch diverting power to a dynamic braking resistor and thus bleed off excess charge from energy storage device, and/or to provide a source control signal to the source side controller (38, 138, 238) to decrease the source side power, wherein the source and grid side controllers are each configured to operate independently when the SOC of the energy storage device is within an acceptable SOC operating range. a renewable power source (12, 112, 212) configured to produce a source power; a source side converter (32, 132, 232) configured to convert the source power to converted DC power; a source side controller (38, 138, 238) configured to drive the converted DC power towards a maximum power point; a DC link (34, 134): configured to receive the converted DC power; a grid side converter (36, 236) coupled to the DC link configured to convert DC link power from the DC link to AC output power for a grid; a grid side controller (40, 140, 240) configured to control the AC output power of the grid side converter to achieve grid interconnection requirements; an electrical energy storage device (42, 142); an energy storage converter (44, 144, 244) configured to couple the energy storage device to the DC link; an energy storage controller (46, 146) configured to control the energy storage converter to achieve a desired power balance on the DC link; and a state of charge SOC, manager configured to receive a SOC signal from the energy storage device (42, 142) and, if the SOC signal is below an acceptable SOC operating range, to provide a respective adjustment signal to the grid side controller (40, 140, 240) to reduce the output power from the grid side converter (36, 236), and/or to the source side controller (38, 138, 238) to increase the source side power so that some energy can be absorbed in the energy storage device (42, 142), and if the SOC is above the acceptable SOC operating range, to provide a grid control signal to the grid side controller (40, 140, 240) to increase the output power to the grid, to switch diverting power to a dynamic braking resistor and thus bleed off excess charge from energy storage device, and/or to provide a source control signal to the source side controller (38, 138, 238) to decrease the source side power, wherein the source and grid side controllers are each configured to operate independently when the SOC of the energy storage device is within an acceptable SOC operating range.