| High-voltage high-power Insulated Gate Bipolar Transistor(IGBT)devices have the advantages of easy driving,fast switching speed,low saturation voltage and wide safe working area,and are widely used in high-voltage large-capacity converter equipment.However,IGBT devices in converter equipment inevitably generate Power Loss(PL)and Electromagnetic Interference(EMI)during switching,which seriously affects the operation reliability of IGBT devices and their converter equipment.The existing research is difficult to accurately characterize the dynamic characteristics of high-voltage high-power IGBT devices so it is impossible to accurately evaluate and control the PL and EMI generated by IGBT devices in converter equipment.Therefore,aiming at the problem of Electromagnetic Transient Model(ETM)and its application of high voltage and high power IGBT devices,this paper has carried out more in-depth research on the ETM,PL and EMI source models and their tradeoff methods of high voltage and high power IGBT devices in converter equipment using theoretical analysis and calculation,supplemented by experimental measurement and verification.Firstly,aiming at the problem of unclear understanding of the electromagnetic transient process of high-voltage and high-power IGBT devices,according to the structural characteristics of high voltage and high power IGBT chips,and considering the carrier storage effect,the idea of modeling the nondual relationship of switching process is proposed,thus establishing the ETM of high-voltage and high-power IGBT devices based on Finite State Machine(FSM),and achieving accurate simulation of the dynamic characteristics of IGBT devices under complex conditions.Compared with the experimentally measured waveform,the simulation error of key parameters such as current and voltage change rate and extreme value is less than 5%.Next,considering the typical characteristics of IGBT device’s switching process in converter,the Switching Equivalent Waveform(SEW)of high-voltage and high-power IGBT devices is proposed.Based on the ETM,the analytical characterization between the time-domain characteristic parameters of the SEW and the system parameters is realized utilizing the time-domain solution of the circuit equation and the low-order linear approximation.Compared with the experimentally measured waveform,the key parameters of SEW have better simulation accuracy,and can accurately characterize the dynamic characteristics of high-voltage and high-power IGBT devices analytically.Then,the spectrum envelope characteristic parameters of SEW are discussed in different frequency bands based on the fundamental properties of Fourier transform,and the analytical characterization of the frequency domain characteristic parameters of the SEW using system parameters is realized.In addition,considering the fastest change of current and voltage in the switching process of the device,the polyline waveform in the SEW is simplified to an asymmetric trapezoidal wave,and the analytical formula of the spectrum envelope of the asymmetric trapezoidal wave is deduced mathematically,which greatly simplifies the characteristic parameters of the SEW in time and frequency domain.Compared with the amplitude-frequency characteristics of the SEW and the experimentally measured waveform before simplification,the spectrum characteristics of the voltage equivalent waveform are almost unaffected,while the current equivalent waveform has a gap of nearly 25dBμA due to the reverse recovery process.Therefore,when the asymmetrical trapezoidal wave is used to simplify the SEW,the influence of current and voltage overshoot on the spectrum characteristics needs to be considered.Further,the time-domain and frequency-domain analysis of the SEW is applied to the solution of PL and conducted EMI in the basic commutation circuit,respectively.The analytical model of PL and conducted EMI in the frequency domain of high-voltage high-power IGBT devices in the basic commutation circuit are established,and the analytical characterization of PL and conducted EMI using system parameters is realized.For the PL analytical model,compared with the experimental measurement results,the PL calculation error of the PL analytical model at the key stage of the device switching process is not more than 10%,and the total PL calculation error is not more than 15%;For the frequency domain analytical model of conducted EMI,taking the spectrum envelope of the current and voltage equivalent waveform as the interference source of Differential Mode(DM)and Common Mode(CM),combining the DM and CM conduction paths,the frequency domain prediction analytical model of conducted EMI is established and compared with the time domain prediction method of conducted EMI,the accuracy of the frequency domain analytical model is verified.Finally,based on the established analytical model of PL and EMI sources,the influence of system parameters on PL and EMI sources is discussed,and the influence rules of drive parameters,device parameters and loop parameters are clarified,thus the tradeoff method of PL and EMI sources based on Nondominated Sorted Genetic Algorithm-Ⅱ(NSGA-Ⅱ)is proposed.Based on the optimization of drive parameters and device parameters,the optimal solution set of drive parameters and device parameters are obtained respectively,which provides the theoretical basis and analysis method for the balance of PL and EMI in the application of IGBT devices. |
PDF Full Text Request