A power generation system comprising: at least two electrical systems connected via a medium voltage collector system to an electrical connection point said electrical connection point being a point of common connection with a grid, each electrical system comprising a power conversion system comprising a respective DC-to-AC converter including a plurality of switches for converting direct current power into alternating current power; and a control system (24, 25) including at least two pulse width modulation modulators, each pulse width modulator obtaining a fundamental waveform to generate a pulse width pattern and for providing the pulse width pattern to a respective DC-to-AC converter for driving the switches of the respective DC-to-AC converter; wherein the control system (24, 25) is configured to interleave the fundamental waveforms of the at least two electrical systems to generate interleaved pulse width patterns respectively for the at least two DC-to-AC converters, wherein each power conversion system further comprises a respective generator side converter for converting alternating current power from a wind turbine generator into direct current power; and wherein the control system further comprises a master controller connected to the electrical connection point, characterised in that: the pulse width modulators additionally obtain a carrier signal and use the fundamental waveform and the carrier signal to generate a pulse width pattern, and the control system (24, 25) is further configured to interleave the fundamental waveforms and carrier signals or a combination of the fundamental waveforms and of carrier signals. at least two electrical systems connected via a medium voltage collector system to an electrical connection point said electrical connection point being a point of common connection with a grid, each electrical system comprising a power conversion system comprising a respective DC-to-AC converter including a plurality of switches for converting direct current power into alternating current power; and a control system (24, 25) including at least two pulse width modulation modulators, each pulse width modulator obtaining a fundamental waveform to generate a pulse width pattern and for providing the pulse width pattern to a respective DC-to-AC converter for driving the switches of the respective DC-to-AC converter; wherein the control system (24, 25) is configured to interleave the fundamental waveforms of the at least two electrical systems to generate interleaved pulse width patterns respectively for the at least two DC-to-AC converters, wherein each power conversion system further comprises a respective generator side converter for converting alternating current power from a wind turbine generator into direct current power; and wherein the control system further comprises a master controller connected to the electrical connection point, characterised in that: the pulse width modulators additionally obtain a carrier signal and use the fundamental waveform and the carrier signal to generate a pulse width pattern, and the control system (24, 25) is further configured to interleave the fundamental waveforms and carrier signals or a combination of the fundamental waveforms and of carrier signals. the pulse width modulators additionally obtain a carrier signal and use the fundamental waveform and the carrier signal to generate a pulse width pattern, and the control system (24, 25) is further configured to interleave the fundamental waveforms and carrier signals or a combination of the fundamental waveforms and of carrier signals.