The Research Of Local Power System With Multi-inverter Loads Based On DC Bus

In traditional AC governor system with multi-inverter load, drive motor is directly supplied by the 3-phase network. Therefore, each motor should be equipped with a set of frequency control device separately. This increases the cost of the system and the high harmonic content, while the energy consumption caused by the braking resistors under the feedback working condition is large.This paper introduces a new program of common DC bus power supply. The program can improve the electric power in two aspects. First, the electric energy generated by the motor under the feedback condition can be absorbed by the motors under the drive condition, optimizing the allocation of energy resources; Second, if the motors get sufficient energy already, the excess electric energy can feed back to the 3-phase network through the feedback device, avoiding the waste of resources.As the full-controlled rectifier shows high power factor, low current harmonics, fast dynamic response, and reversible power supply, it can act well as the AC/DC power conversion device in public DC bus. All-controlled rectifier is usually controlled by SPWM strategy, but SVPWM has the better dynamic performance and voltage utilization than the SPWM. Therefore, the SVPWM control strategy is adopted by my paper. This strategy makes rectifier system with the advantages of two-way flow of energy. Eliminating the feedback device, the system's structure has been simplified.In this paper, the working principle and the structure of the voltage PWM rectifier is expounded; the implementation of SVPWM control strategy is systematically expounded; the dynamic response process of the public DC bus system is analyzed; the local load capacity is calculated. On this basis, under the application of MATLAB software, the mathematical model and the package are constructed. Local power system simulation model under DC bus is set up. The process of the dynamic response of public DC bus is simulated. Finally a reasonable simulation results is given.In this paper, with TI TMS320F2812 development board as the core, the full-controlled PWM rectifier of low-power prototype system is completed. The system hardware includes the main circuit (IGBT drive circuit), and control circuit (phase voltage/current detection, over-current protection, zero detection, phase-locked loop, the DC voltage detection circuit). The model numbers of the devices are selected. Experimental results show that the PWM rectifier under SVPWM strategy acts full control of the Common DC bus with good robust performance.