In predictive direct power control(PDPC)system of three-phase pulse width modulation(PWM)rectifier,grid voltage sensor makes the whole system more complex and costly.Therefore,third-order generalized integrator(TOGI)i...In predictive direct power control(PDPC)system of three-phase pulse width modulation(PWM)rectifier,grid voltage sensor makes the whole system more complex and costly.Therefore,third-order generalized integrator(TOGI)is used to generate orthogonal signals with the same frequency to estimate the grid voltage.In addition,in view of the deviation between actual and reference power in the three-phase PWM rectifier traditional PDPC strategy,a power correction link is designed to correct the power reference value.The grid voltage sensor free algorithm based on TOGI and the corrected PDPC strategy are applied to three-phase PWM rectifier and simulated on the simulation platform.Simulation results show that the proposed method can effectively eliminate the power tracking deviation and the grid voltage.The effectiveness of the proposed method is verified by comparing the simulation results.展开更多
In this paper, a vector regulating principle of the phase and amplitude control PAC method for three-phase grid-connected inverters is presented.To solve the problem of heavy inrush current and slow dynamic response w...In this paper, a vector regulating principle of the phase and amplitude control PAC method for three-phase grid-connected inverters is presented.To solve the problem of heavy inrush current and slow dynamic response when system starts up, the starting voltage prediction control and the current feed-forward control are proposed and used, which improve the dynamic performance of the system in the PAC.The experimental results carried out on a three-phase grid-connected inverter proved the validity of the proposed method.展开更多
To solve the input current harmonic pollution of the high power rectifier system,18-pulse rectifier based on a kind of active harmonic suppression technique at dc side is proposed in this paper.The pulse rectifier emp...To solve the input current harmonic pollution of the high power rectifier system,18-pulse rectifier based on a kind of active harmonic suppression technique at dc side is proposed in this paper.The pulse rectifier employs three-phase diode bridges,each of them followed by a boost converter.Unlike the conventional three-phase unity-power-factor diode rectifier,the ideal sinusoidal main currents of circuit topology are obtained by control its output current or input currents of three boost converters for approximately triangular modulation.The theoretical of modulation strategy and characteristics of input and output currents about the proposed rectifier are analyzed in detail.Simulation results by Matlab/Simulink demonstrate that the proposed rectifier draws nearly sinusoidal current and power quality index is improved.The correctness of the theoretical analysis is validated.展开更多
This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in t...This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in the alternator changes according to the vehicle speed, more over the loading effect on the alternator introduces harmonic currents and increases the alternator apparent power requirements. To overcome these problems and aiming more stability and better design of the alternator, a new third harmonic injection technique is proposed. This technique allows to preserve a good THD (Total Harmonic Distortion) of the input source at any frequency and to decrease losses in semiconductors switches, thereby allowing more stability and reducing the apparent power requirements. A comparative study between the standard and the new technique is made and highlights the effectiveness of the new design. A detailed analysis of the proposed topology is presented and simulations as well as experimental results are shown.展开更多
基金National Natural Science Foundation of China(Nos.51767013,52067013)。
文摘In predictive direct power control(PDPC)system of three-phase pulse width modulation(PWM)rectifier,grid voltage sensor makes the whole system more complex and costly.Therefore,third-order generalized integrator(TOGI)is used to generate orthogonal signals with the same frequency to estimate the grid voltage.In addition,in view of the deviation between actual and reference power in the three-phase PWM rectifier traditional PDPC strategy,a power correction link is designed to correct the power reference value.The grid voltage sensor free algorithm based on TOGI and the corrected PDPC strategy are applied to three-phase PWM rectifier and simulated on the simulation platform.Simulation results show that the proposed method can effectively eliminate the power tracking deviation and the grid voltage.The effectiveness of the proposed method is verified by comparing the simulation results.
基金supported by the Shanghai Education Committee Scientific Research Subsidization (Grant No.05AZ30)the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20060280018)
文摘In this paper, a vector regulating principle of the phase and amplitude control PAC method for three-phase grid-connected inverters is presented.To solve the problem of heavy inrush current and slow dynamic response when system starts up, the starting voltage prediction control and the current feed-forward control are proposed and used, which improve the dynamic performance of the system in the PAC.The experimental results carried out on a three-phase grid-connected inverter proved the validity of the proposed method.
基金Natural Science Foundation of Gansu Province Education Department(No.2017A-020)National Natural Science Foundation of China(No.51767013)Science and Technology Research and Development Plan of China Railway Corporation(No.2017J012-A)
文摘To solve the input current harmonic pollution of the high power rectifier system,18-pulse rectifier based on a kind of active harmonic suppression technique at dc side is proposed in this paper.The pulse rectifier employs three-phase diode bridges,each of them followed by a boost converter.Unlike the conventional three-phase unity-power-factor diode rectifier,the ideal sinusoidal main currents of circuit topology are obtained by control its output current or input currents of three boost converters for approximately triangular modulation.The theoretical of modulation strategy and characteristics of input and output currents about the proposed rectifier are analyzed in detail.Simulation results by Matlab/Simulink demonstrate that the proposed rectifier draws nearly sinusoidal current and power quality index is improved.The correctness of the theoretical analysis is validated.
文摘This paper presents a PFCVF (Power Factor Correction) rectifier that uses a variable frequency source for alternators for electric and hybrid vehicles application. In such application, the frequency of the signal in the alternator changes according to the vehicle speed, more over the loading effect on the alternator introduces harmonic currents and increases the alternator apparent power requirements. To overcome these problems and aiming more stability and better design of the alternator, a new third harmonic injection technique is proposed. This technique allows to preserve a good THD (Total Harmonic Distortion) of the input source at any frequency and to decrease losses in semiconductors switches, thereby allowing more stability and reducing the apparent power requirements. A comparative study between the standard and the new technique is made and highlights the effectiveness of the new design. A detailed analysis of the proposed topology is presented and simulations as well as experimental results are shown.
