Research On Shunt PFC Technology

As an effective method to restrain the harmonic and improve power factor, Power Factor Correction (PFC) technology has become hot research topic in the power electronics technology field. Compared with the traditional Series PFC technology, Shunt PFC technology has merits such as following: It doesn't need to manage all the AC/DC transform power, and it just has to manage harmonic and passive power; with shunt inverter, it can achieve large capability harmonic compensation under low switch frequency.In this paper the principle of Shunt PFC technology is introduced. Then shunt inverter with CPS-SPWM technique has been proposed, which is the combination of shunt structure and CPS-SPWM technique. The high equivalent switch frequency can be obtained with low switch frequency devices, and it has a perfect performance on harmonic feature. Shunt structure is applied to reduce the device currents rate and switch stress, and the dc bus voltage balance can be achieved easily. As the topology of shunt PFC technology, shunt inverter based on CPS-SPWM technique is very promising in large power applications.Shunt inverter with CPS-SPWM technique has been discussed in application of Shunt PFC technology. The dc-side and ac-side control strategies have been researched, and the simulation study is carried out. Simulation result shows the Shunt PFC system is of good compensation and PFC performance.On the base of theoretical analysis and simulated research, a prototype of the shunt PFC system based on TMS320LF2407 is realized. The system contains some modules such as detecting circuit, DSP micro-controller, power circuit, and so on. All the design rules of the modules above have been introduced in detail. The system experiment is performed and the experimental result is given. The experimental result proves that the shunt PFC system can achieve excellent PFC effect even under low switch frequency.