Application And Research Of Inverter Technology In AC Regulator

For the time being, the grid voltage problems such as the grid unsteady and the serious harmonics injected by a large number of non-linear loads are becoming more and more serious and are spreading widely. The non-ideal grid voltage has greatly impact on the performance and security of electrical equipments, especially on the accurate electrical equipments which demand high quality of grid voltage. Adopting stabilized power supply can meet the needs of the equipments for the AC supply, and therefore the stabilized power supply has been widely used in daily life, agricultural and industrial productions.The structure and working principle of AC stabilized voltage power supply is presented in detail in this paper, and a compensative AC stabilized voltage power supply, which is based on inverter technology, is designed. The proposed power supply is with series structure and can realize the high output accuracy of sinusoidal steady voltage by utilizing the voltage compensation principle and inverter technology. The main work of this paper is as follows:The existing states on the AC stabilized voltage power supply are analyzed, and the advantages and disadvantages of them are summarized, and then the significance of this research is given.The structure and the working principle of the inverter AC regulator are studied, and the main circuit, voltage detection method, regulator principle and energy transmission for the regulator are also detailed. The series compensative AC stabilized voltage power supply topology, which is consisted of a voltage control unit of H-bridge inverter and a SPWM rectifier circuit, is presented and the theoretical calculation is carried out. The proposed topology can effectively reduce a large number of harmonic current generated by the diode rectifier, which is contribute to the bidirectional energy flow between grid and the inverter.The control structure of the previous power supply is investigated, and a novel three closed-loop feedback control strategy is proposed. After deeply study of the basic working principle of the novel control strategy, the novel controller is designed, which contains an out ring of output voltage RMS, a middle ring of instantaneous output voltage value and an inner ring of instantaneous capacitor current value.In the platform of MATLAB/SIMULINK, the proposed power supply model is established, and the circuit structure and control algorithm is simulated. Analyzing the experimental data, it is easy to conclude that the novel control strategy effectively improves the accuracy of the stabilized voltage power supply and reduces the output voltage harmonic components. Thus results also demonstrate the correctness and feasibility of the proposed AC stabilized voltage power supply topology and the three-loop feedback control strategy.