Transformer coupling and separately excited active tuned hybrid filter and control method

The invention relates to a transformer coupling and separately excited active tuned hybrid filter and a control method. The hybrid filter comprises a separately excited supply (SES), an active power filter (APF) and a passive power filter (PPF), wherein the PPF comprises a filter capacitor C and a filter reactor L, which are connected in series with each other; the output of the SES is connected to the direct current side of the APF, and the output end of the APF is connected in parallel to two ends of the filter reactor L of the PPF via a coupling transformer T; and both the SES and the APF adopt voltage source converter circuits of insulated gate bipolar transistor (IGBT) and PWM (Pulse Width Modulation) technologies. The hybrid filter is better in compensation performance and simpler in control structure; the PPF branch serves as a main channel for carrying harmonics, and the APF achieves a tuning control effect, so that the passive LC filter branch can achieve a good effect of filtering multiple specific