| With the development of the variable speed system, general inverter have a wide applications in practice. But the part of convert is not reversible, this decide the limit in variable speed system. When motor run during the regenerative braking, the energy is fed back from the motor to the filtering capacitance in the DC side of general inverter, generates pump voltage. Usually by braking resistance and braking unit consume the energy, this is not only waste energy, but also build side effect. For these problems, people give an idea of feeding energy to power.Firstly the basic principle of the energy feedback equipment and SPWM technology is introduced in details. On this basis, the high and low-frequency mathematical model under ABC stationary reference frame and dq rotation reference frame are constructed. In this paper, it presents the indirect and direct current control, and points out the differences between them. Furthermore, it propose the principal algorithm of control strategy and established the simulation model.Then this paper describes the design of the system hardware, including power part and control part. Power part is made up of the main circuit, control part is made up of the current detection circuit, voltage detection circuit, lock-on circuit and drive&protection circuit. Control part adopts dsPIC30f2010 as the core chip generating the drive voltage of SPWM. The software realizes various kinds of functions, including the basic function of the energy-feedback device, assistant function as protection and voltage adaptive control.The experiment has realized the single-phase and three-phase system. The results show that the system has good dynamic performance and steady performance which has notable energy-saving effect. The device breakdown problem is discussed at last, and this paper gives a design of software to solve it.
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