基于諧波等值電路的兩級(jí)式DC/DC變換器建模方法研究
王建宇1，徐修華2，李晗3
（1 江蘇句容抽水蓄能有限公司, 江蘇 句容 212416；2 國網(wǎng)浙江寧波市奉化區(qū)供電有限公司，浙江 寧波 315500；
3 國網(wǎng)江蘇省電力有限公司徐州供電分公司，江蘇 徐州 221006）
摘 要：采用諧波狀態(tài)空間法對(duì)兩級(jí)式DC/DC變換器建模時(shí)，狀態(tài)變量的增加使系統(tǒng)變得復(fù)雜，斬波子模塊間開關(guān)頻率的不同導(dǎo)致模型基頻不確定，系統(tǒng)諧波狀態(tài)描述難以獲得。基于時(shí)變周期系統(tǒng)理論和狄利克雷條件，建立了各子模塊的諧波狀態(tài)空間模型，繪制了各子模塊的諧波等值電路圖；根據(jù)基爾霍夫定律，得到了整個(gè)系統(tǒng)的諧波；用諧波阻抗代替周期性開關(guān)行為簡化了電路；提出了多開關(guān)頻率背景下諧波狀態(tài)方程基頻的確定方法，在簡化等值電路的基礎(chǔ)上推導(dǎo)了兩級(jí)DC/DC變換器的諧波狀態(tài)空間模型。仿真結(jié)果表明，等值電路引入的諧波狀態(tài)空間模型具有較高的精度，在以直流配電網(wǎng)為背景的多級(jí)DC/DC變換器頻率耦合研究中具有較高的應(yīng)用價(jià)值。
關(guān)鍵詞：諧波狀態(tài)空間；時(shí)變周期系統(tǒng)；諧波等值電路；多開關(guān)頻率
中圖分類號(hào)：TM46 文獻(xiàn)標(biāo)識(shí)碼：A 文章編號(hào)：1007-3175(2021)03-0013-07
Two-Stage DC/DC Converter Modeling Method Based on Harmonic Equivalent Circuit
WANG Jian-yu1, XU Xiu-hua2, LI Han3
（1 Jiangsu Jurong Pumped Storage Co., Ltd, Jurong 212416, China;
2 Fenghua Power Supply Company, State Grid Zhejiang Electric Power Company, Ningbo 315500, China;
3 State Grid Jiangsu Electric Power Co., Ltd Xuzhou Power Supply Company, Xuzhou 221006, China）
Abstract: When the two-stage DC/DC converter is modeled by the harmonic state space method, the harmonic state equation cannot be written due to the complicated system operation and the increase of state variables. The different switching frequencies between the chopping sub-modules lead to the model fundamental frequency unconfirmed. Based on the time-varying periodic system theory and the Dirichlet condition, the harmonic state space model of the sub-module is established, and the harmonic equivalent circuit of each sub-module is drawn. According to Kirchhoff 's law, the harmonics of the whole system are obtained. The circuit is simplified by using harmonic impedance instead of periodic switching behavior. Finally, the fundamental frequency determination method of harmonic state equation in multi-switching frequency background is proposed. The harmonic state space model of two-stage DC/DC converter is derived based on the simplified circuit. The simulation results show that the harmonic state space model introduced by the simplified equivalent circuit has higher accuracy and has higher value in the study of the frequency coupling of multi-stage DC/DC converters with DC distribution network as background.
Key words: harmonic state space; time-varying periodic system; harmonic equivalent circuit; multi-switching frequency
參考文獻(xiàn)
[1] MIDDLEBROOK R D.Small-signal modeling of pulse-width modulated switched-mode power converters[J].Proceedings of the IEEE，1988，76(4)：343-354.
[2] PERREAULT D J, VERGHESE G C.Time-varying effects and averaging issues in models for current-mode control[J].IEEE Transactions Power Electronics，1997，12(3) ：453-461.
[3] MAHDAVI J, EMAADI A, BELLAR M D, et al. Analysis of power electronic converters using the generalized state-space averaging approach[J].IEEE Transactions Circuits and Systems I：Fundamental Theory and Applications，1997，44(8) ：767-770.
[4] YAHYAIE F, LEHN P W.On dynamic evaluation of harmonics using generalized averaging techniques[J]. IEEE Transactions Power Systems，2015，30(5) ：2216-2224.
[5] YUE X, WANG F, YANG S, et al.Modeling for input impedance of buck converters and its application analysis[C]//2015 IEEE Energy Conversion Congress and Exposition，2015 ：2400-2406.
[6] YUE X, ZHU Y, YANG S, et al.A modulation and sampling based modeling method for the nonlinearities of power converters and its application analysis[C]//2015 17t h European Conference on Power Electronics and Applications，2015 ：1-10.
[7] ARRILLAGA J, WATSON N.The harmonic domain revisited[C]//13th International Conference on Harmonics and Quality of Power，2008 ：1-9.
[8] VYAKARANAM B, MADRIGAL M, VILLASECA F E, et al. Dynamic harmonic evolution in FACTS via the extended harmonic domain method[C]//2010 Power and Energy Conference Illinois，2010：29-38.
[9] WERELEY N M.Analysis and control of linear periodically time varying systems[D]. Massachusetts ：Massachusetts Institute of Technology，1991：217-223.
