Wind Turbines

Several different types of power electronics architectures have been used for wind turbines, but 4-quadrant full converters have emerged as the most popular solution due to providing superior grid support and wider turbine operating range.

A conventional full converter consists of a two stage or “back-to-back” converter where the first stage provides asynchronous AC to DC conversion (rectification) and the second stage provides DC to AC conversion (inversion). Lastly a dedicated transformer is required for each turbine to provide isolation and step up the voltage to medium output voltage.




The IPC wind turbine power converter uses a single stage asynchronous AC to synchronous AC conversion without an intermittent DC link stage. The major benefits of IPC’s single stage wind converter include:

• Lower weight, lower size and lower cost of wind converter.
• Higher efficiency, particularly when the turbine is operating at only 10-30% of rated power.
• Support for low cost AC induction generators eliminating the need for permanent magnets with rare earth elements.
• Low dv/dt and harmonics to the generator reducing generator costs, while increasing reliability and efficiency. (See VFD whitepaper)
• Low harmonic energy to the grid reducing output filter requirements. The IPC converter also provides reactive output, low voltage ride-through and the capability to add a low cost battery interface. (See application page for Combined PV and Battery Inverter.)

A wider operating range may help enable use of direct drive turbines without a gearbox. The inherently low harmonic AC output stage supports reactive power and low voltage ride-though. The direct power transfer enables ground isolation and combined with higher AC output voltage, may allow multiple turbines to share a common step up transformer.

IPC initial product for wind turbines will be a 30kW wind converter using that same proven power converter platform as its photovoltaic inverter.  This product will provide 480VAC 3-phase output without requiring a transformer.  It targets a new class of medium-scale distributed wind turbines systems.

Single Stage AC-AC Converter for Wind Turbines Whitepaper