Maximum Power Point Tracking for Wind Turbine Using Integrated Generator-Rectifier Systems

Off-shore wind is a rapidly growing renewable energy resource. Harvesting energy far from the coast requires multi-megawatt wind turbines and high efficiency, high power density, and reliable power conversion systems to achieve a competitive levelized cost of energy. An integrated system utilizing one active and multiple passive rectifiers with a multi-port permanent magnet synchronous generator is a promising alternative compared to the conventional electro-mechanical power conversion systems. Deployment of the integrated systems in off-shore wind energy requires maximum power point tracking (MPPT) capability, which seems to be challenging due to the presence of numerous uncontrolled passive rectifiers. This paper shows MPPT is feasible through a power-flow control framework. The framework is based on a finding that the active rectifier d-axis current can control the total system output power. The MPPT capability opens up multiple opportunities for the integrated systems in off-shore wind applications.