The control of a series wound electrical machine in an electrically operated vehicle

摘要

For control of the field weakening (5, 6) in a series wound machine (2, 3) in an electrically operated vehicle such as a fork lift truck, the request (8) for field weakening given by the operator is carried out only if certain conditions (9, 10, 11, 12) are met, such as a prescribed actual travel speed (10) and a prescribed speed demand setting (9) of the travel command pickup being exceeded. Predetermined operating mode(s) (ie whether generation or motor operation or direction setting) must also be detected (11, 12) before field weakening is instigated or maintained.