The Design Of Polysilicon Deoxidization Furnace Heating Power Supply

As the global energy increasingly scarce and the rapid development of renewable energy, photovoltaic energy industry gradually has mushroomed into the important component of world energy. And polysilicon is the main raw materials of solar cells of photovoltaic power generation, so polysilicon raw material is the bottleneck of photovoltaic industry development. The core production technology of polysilicon is long-term in the hands of several foreign core enterprises, which makes the development of domestic polysilicon industry slowly. Therefore, it is important significance to develop a set of domestic independent polysilicon deoxidization furnace dc electrical system.This paper has developed the domestic first dc electrical system IGBT chopper deoxidization heating power for the deoxidization growth of silicon rods. The experimental circuit of IGBT chopper deoxidization heating power is combination of six Buck circuits, called an IGBT chopper chest. According to the growth character of polysilicon, the whole glowth process of silicon rods can be divided into two stages. In lage voltage and small current, silicon rods run separately and six Buck circuits are respectively divided into three groups operating for three silicon rods alone to supply power. In small voltage and large current stage, silicon rods run in series, six Buck circuits are parallel operating for three serial silicon rods to supply power. Establishing a Buck circuit experimental prototype, and making experiments to choose power device IGBT and power inductor that are suitable for polysilicon deoxidization furnace heating power system to complete the whole system hardware circuit design. The single Buck circuit working principle and multi-channel parallel Buck circuits working principle analyses have been made, and the parallel-running interlacing control strategy has been put forward. The control system adopts TMS320F28335 DSP chip as the master by sampling the inductance current of each Buck circuit, and PWM control has been made both in silicon rods independent operation condition and silicon rods series operating condition, so as to realize the output voltage and current of the silicon rods load required. Detailed introduction of the hardware design of the control system has been made, including DSP control circuit design and based on the M57962L drive chip push-pull amplifier drive circuit plus circuit design.