Research On Current Mode High Frequency Link Matrix Rectifier Based On De-re-coupling Vector Modulation

Current mode high-frequency link matrix rectifier is a new type of power converter which derived from the traditional matrix converter topology,it consists of LC input filter,matrix converter,high-frequency transformer,uncontrolled rectifier,output filter L and load.It can not only realize the AC/DC transformation,but also has sinusoidal input current and unity power factor,lack of bulky energy storage compoents,high frequency and other fine performance.Due to the high frequency link matrix rectifier uses bidirectional switch to carry out energy conversion,so modulation is the foundation of the rectifier.Because the high frequency transformer and the circuit contain leakage inductance,improper selection of modulation strategy will result in large voltage spikes across the switch,so now the urgent need to study a new modulation strategy to solve the safe commutation of high-frequency link matrix rectifier switch tubes.Firstly,this paper takes direct transformation three-phase to single-phase matrix converter and three-phase current mode high-frequency link matrix rectifier as the research objects,in order to make direct transformation three-phase to single-phase matrix converter output positive and negative DC,this paper proposes traditional three-phase current type de-re-coupling vector modulation,it combines de-re-coupling modulation with current space vector pulse width modulation(SVPWM)which based on the expected input current of 12 sectors classification.Then,in order to make the direct transformation three-phase to single-phase matrix converter output high frequency AC and frequency AC under the sense of resistance-inductance load,and ensure bidirectional switch tubes can realize safe commutation,this paper proposes the optimized three-phase current type de-re-coupling vector modulation.Afterwards,the above two modulation strategies are applied to the three-phase current mode high-frequency link matrix rectifier,in this paper,it analyzes the working principle of two kinds of modulation in the case of high frequency transformer,and carries out modal analysis for three-phase current mode high-frequency link matrix rectifier based on traditional three-phase current type de-re-coupling vector modulation.Secondly,aiming at the modulation of single-phase current mode high-frequency link matrix rectifier,in this paper,de-re-coupling unipolar PWM modulation and single-phase current space vector modulation are improved respectively,this paper puts forward optimized de-re-coupling unipolar PWM modulation and single-phase de-re-coupling vector modulation,and analyzes the specific work process.Then,this paper establishes mathematical model of three-phase current mode high-frequency link matrix rectifier which combines optimized three-phase current type de-re-coupling vector modulation with the modeling method of three-phase current source rectifier(CSR).After that,this paper designs the parameters of double closed-loop which includes DC side current outer loop and network side AC current inner loop based on dq coordinate.Finally,this paper designs hardware circuit and software program of the experimental system based on theoretical analysis and simulation verification,and builds high-frequency link matrix rectifier experimental platform with the controlling core of DSP+CPLD,and the experimental results verify the the validity of the proposed modulation strategy.