Method and device for determining the optimal exitation value which minimizes the eletromagnetic losses of electric machines

摘要

The invention relates to a method and an electronic device for determining the optimal excitation value (stator current, magnetic flux, magnetic induction) which minimizes the electromagnetic (copper and iron) losses of dc and vector-controlled ac machines. The invention provides the command to the excitation control loop of the said electric machines.The invention is characterized by the multiplication or amplitude-modulation (1) of a periodic signal of angular frequency proportional to the speed of the electric machine, a first-order low-pass filter (2), an amplifier (3) and a peak detector (4). The output of the peak detector (4) provides the optimal command to the excitation control loop of the electric machine.