In the hybrid AC-DC-AC electric drive system of engineering equipment，the PMSM usually regenerates excessive braking energy to the D.C bus during the regenerated braking process.The excessive energy is likely to cause the D.C bus voltage pumping and reduces the operating performance of engine.To solve this problem，this paper analyzes the reason of D.C bus voltage pumping in the braking process from the view of the non-coincidence of the DC/DC and the inverter.On this basis，a control strategy of a feed-forward compensation added to the FOC outer loop is proposed.This strategy uses the PD controller to deal with the error between the D.C bus voltage and its reference value，and then adds the outputs of PD controller to the reference of iq，so that the iq and the duty cycle of inverter can be both reduced.The regenerated power of PMSM is also limited.The simulation results show that the proposed control strategy can effectively improve the problem of D.C bus voltage pumping during the PMSM regenerated braking process，which is good for the electrical safety protecting in the D.C bus.