System and Method for Controlling DC Link Voltage of a Power Converter

A method for operating a wind turbine power system connected to a power grid, the wind turbine power system having a power converter electrically coupled to a generator, the method comprising:

• operating the generator within a first operating rotor speed range and monitoring a rotor speed of the generator;
• increasing the operating rotor speed range to a second operating rotor speed range and monitoring the rotor speed of the generator;
• determining at least one of a line-side voltage of a line-side converter of the power converter or a rotor-side voltage of a rotor-side converter of the power converter during operation of the electrical power circuit;
• and,
• controlling, via a converter controller, a DC link voltage of a DC link of the power converter as a function of at least one of the line-side voltage or the rotor-side voltage and the rotor speed.

An electrical power circuit, comprising:

• a generator having a rotor and a stator;
• a power converter comprising a line-side converter electrically coupled to a power grid and a rotor-side converter electrically coupled to the generator;
• and,
• a controller communicatively coupled to at least one of the power converter and the generator, the controller configured to perform one or more operations, the operations comprising:
• monitoring a rotor speed of the generator during operation of the electrical power circuit;
• increasing an operating range of the rotor speed of the generator;
• determining at least one of a line-side voltage of the line-side converter or a rotor-side voltage of the rotor-side converter during operation of the electrical power circuit;
• and,
• controlling a DC link voltage of a DC link of the power converter as a function of at least one of the line-side voltage, the rotor-side voltage, or the rotor speed.