Abstract:In recent years, with the continuous improvement of the intelligence of low-voltage power distribution systems, the application of compound switches in 0.4 kV reactive power compensation systems has gradually been widely used. Its advantages such as rich protection functions, small inrush current of switching capacitor and low steady loss, are acknowledged by the users. According to incomplete statistics, dozens of new manufacturers have been added to develop the compound switches from 2015 to 2021, but the uneven technical level leads to frequent problems in the use of products. Aiming at the problems existing in the operation of compound switches in reactive power compensation system, the concept of interactive control strategy based on handshake is proposed. The application effect is described, and a stable and reliable hardware output and feedback circuit, software control strategy and practical solution are designed. And the effectiveness and reliability of the proposed control strategy are verified through the practical application in engineering.