Controlled switching current of an on-load tap changer of a wind turbine

• Main Authors: Hillebrandt, Jesper, Kjær, Philip Carne
• Format: Patent
• Language: English
• Published: 23.08.2022
• Subjects: BLASTING; CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORSOR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; HEATING; LIGHTING; MACHINES OR ENGINES FOR LIQUIDS; MECHANICAL ENGINEERING; OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR; PRODUCING MECHANICAL POWER; WEAPONS; WIND MOTORS; WIND, SPRING WEIGHT AND MISCELLANEOUS MOTORS

The invention relates to a method for controlling a wind turbine which comprises a transformer has a variable turns ratio such as an on load tap changer transformer. The adjustment of the turns ratio is possible when a primary side current or a secondary side current of the transformer is less than a switching current threshold. The method comprises operating the wind turbine so that the primary or secondary side current is above the switching current threshold. In response to obtaining a condition for changing the turns ratio of the transformer, the wind turbine is operated so that the primary or secondary side current is reduced below the switching current threshold so that the turns ratio can be changed during the temporary current reduction.