風(fēng)力發(fā)電網(wǎng)側(cè)變流器控制策略研究(編輯修改稿)

　

【文章內(nèi)容簡(jiǎn)介】 e. Modern power eletronics and AC drives. Beijing: China Machine Press, 2003.]。線性控制包括PI調(diào)節(jié)控制[6,J. R. Rodrigue, J. W. Dixon, J R Espiaoza, et al. PWM regenerative rectifier: state of the art. IEEE Trans. on Industrial Electronics, 2005,52(1):522.,M. P. Kazmierkowski, L. Malesani. Current control techniques for threephase voltagesource PWM converters: a survey. IEEE Trans. on Industrial Electronics, 1998, 45(5):691703.]、狀態(tài)反饋控制[T. M. Rowan, R. J Kerkman. A New Synchronous Current Regulator and Analysis of Current Regulator PWM Inverter. IEEE Trans. on , 1986,IA22(4):678690.,N. R. Zargari, G .Joos. Performance investigation of a currentcontrolled voltageregulated PWM rectifier in rotating and stationary frames. IEEE Trans. on Industrial Electronics, 1995,42(4):396401.]、預(yù)測(cè)電流控制[C. T. Rim, N. S. Choi, G. C. Cho,et al. A plete DC and AC analysis of three of threephase controlledcurrent PWM rectifier using DQ transformation. IEEE Trans. on Industrial Electronics, 1994, 9(4): 390396.,A. Draou, Y. Sato, T. Kataoka. A new state feedback based transient control of PWM AC to DC voltage type converters, Trans. on Industrial Electronics, 1995, 10(6): 716724.]等；非線性控制包括滯環(huán)電流控制[鄧衛(wèi)華，張波，氏東元．二相電壓型PWM整流器狀態(tài)反饋精確線性化解耦控制研究．中國(guó)電機(jī)一程學(xué)報(bào)，2005，25（7）：97103.,R. Wu, S. B. Dewan, G. R. Slemon. Analysis of a PWM AC to DC voltage source converter under the predicted current control with a fixed switching frequency. IEEE Trans. on Industry Application, 1991, 27(4):756764.,L. Zhang, F. Hardan. Vector controlled VSIfed AC drive using a predictive spacevector regulation scheme. 20th International Conference on Industrial Electronics, Control and Instrumentation, Bologna, Italy, 1994, 1: 6166.]、模糊控制[W. McMurray. Modulation of the chopping frequency in DC choppers and PWM inverters having currenthysteresis controllers. IEEE Trans. on Industry Application, 1984, IA20(4):763768.,L. Malesani, P. Tenti. A novel hysteresis control method for currentcontrolled voltagesource PWM inverters with constant modulation frequency. IEEE Trans. on Industry Application, 1990, 26(1): 8892,I. Nagy. Novel adaptive tolerance band based PWM for field oriented control of induction machines. IEEE Trans. on Industrial Electronics, 1994, 41(4):406417.]、神經(jīng)網(wǎng)絡(luò)控制[C. Cecati, A. Dell’Aquila, M. Liserre, et al. A FuzzyLogicBased Controller for Active Rectifier. IEEE Trans. on Industry Application, 2003, 39(1):105112.,S. Saetieo, D. A. Torrey. Fuzzy logic control of a spacevector PWM current regulator for threephase power converters. IEEE Trans. on Power Electronics, 1998, 13(3): 419426.,C. Cecati, A. Dell’Aquila, A Lecci, et al. Implemention issues of a fuzzy logic based three phase active rectifier employing only voltage sensors. IEEE Trans. on Industrial Electronics, 2005, 52(2): 378385. ]等。其中，基于坐標(biāo)變換理論的調(diào)節(jié)控制獲得了最為廣泛的應(yīng)用，按照坐標(biāo)定向方法的不同，又可將其分為基于網(wǎng)側(cè)電壓（Voltagebased）的控制策略和基于虛擬磁鏈（Virtual fluxbased）的控制策略?xún)深?lèi)，前者主要包括電壓定向控制（Voltage orientd control, VOC），和直接功率控制（Direct power control, DPC），后者主要包括虛擬磁鏈定向控制（Virtual flux orientd control, VFOC）和虛擬磁鏈—直接功率控制（Virtual flux direct power control, VFDPC），如文獻(xiàn)[, K. Khorasani. DSP implementation of neural network based controller for voltage PWM rectifier neural. IEEE TENCON Digital Signal Processing Applications Proceedings, Perth, WA, Australia, 1996, 2: 883888.]所述。以上控制算法還可以和電壓、電流估算方法相結(jié)合，形成三相VSC無(wú)電壓、電流傳感器控制策略，進(jìn)一步提高系統(tǒng)可靠性。例如，文獻(xiàn)[M. Cichowlas, M. P. Kazmierkowski. Comparison of current control techniques for PWM rectifiers. IEEE International Symposium on Industrial Electronics, L’Aquila, L’Aquila, Italy, 2002, 4: 12591263]研究了網(wǎng)側(cè)電壓和中間直流電壓的估算方法，文獻(xiàn)[L. H. Tey, P. L. So, Y. C. Chu. Adaptive neural network control of active filters. Electric Power System Research, 2005, 74(1):3756]研究了無(wú)網(wǎng)壓傳感器的VOC和DPC控制策略，并對(duì)兩者的優(yōu)缺點(diǎn)進(jìn)行了分析對(duì)比。鑒于濾波效果較好且使用的電感值也較小的優(yōu)點(diǎn)，LCL濾波器在MW級(jí)風(fēng)機(jī)并網(wǎng)變流器中得到廣泛使用。然而LCL濾波器對(duì)系統(tǒng)引入了一個(gè)零阻抗諧振頻率點(diǎn)，如果沒(méi)有適當(dāng)?shù)淖枘?，系統(tǒng)穩(wěn)定性將受到影響。為了抑制濾波器的諧振，人們研究了相應(yīng)的諧振阻尼辦法，主要可分為無(wú)源阻尼（Passive damping）和有源阻尼（Active damping）兩大類(lèi)。無(wú)源阻尼法是通過(guò)直接加入電阻以增加系統(tǒng)阻尼，設(shè)計(jì)上簡(jiǎn)單可靠，文獻(xiàn)[M. Liserre,F. Blaabjerg, S. Hansen. Design and control of an LCLfilter based threephase active rectifier. IEEE Trans. on Industrial Applications. 2005, 41(5):12811291.,T. C. Wang, Z. H. Ye, G. Sinha, et al. Output Filter Design for a Grid interconnected Three Phase Inverter [C]// Proc. of PESC’03, 2003,2: 779784.]即采用這種方法。但是阻尼電阻的損耗使得系統(tǒng)效率降低，在高壓大功率場(chǎng)合阻尼電阻發(fā)熱嚴(yán)重，可能需要強(qiáng)制風(fēng)冷。為有效解決效率和穩(wěn)定性之間的矛盾，用算法來(lái)代替實(shí)際電阻的有源阻尼法逐漸引起了學(xué)術(shù)界的關(guān)注，具體實(shí)現(xiàn)方法多種多樣，目前主要有虛擬電阻、超前滯后網(wǎng)絡(luò)等方法。和無(wú)源阻尼相比,有源阻尼方法能夠避免阻尼電阻引起的額外效率損失，但也造成了控制算法的復(fù)雜化。Pekik Argo Dahono提出了“虛擬電阻”的思想來(lái)替代實(shí)際電阻[P. A. Dahono. A control method for DCDC converter that has an LCL output filter based on new virtual capacitor and resistor concepts [C]// Proc. of PESC’04, 2004, 1: 36 42.]，與無(wú)源阻尼類(lèi)似，該文提出了四個(gè)可能的可以替代實(shí)際電阻的控制算法。該方法由于具有簡(jiǎn)明的物理意義，因而在工業(yè)上獲得了一定的應(yīng)用。V. Blasko提出了基于超前滯后模塊（LeadLag）的濾波電容電壓反饋AD方法[V. Blasko, V. Kaura. A novel control to actively damp resonance in input LC filter of a three phase voltage source converter[J]. IEEE Transactions on Industry Applications, 1997, 33(2): 542550.]。在此基礎(chǔ)上，Marco Liserre利用z域分析系統(tǒng)傳遞函數(shù)的方法對(duì)超前網(wǎng)絡(luò)參數(shù)的選擇以及對(duì)系統(tǒng)特性的影響做了分析[M. Liserre, A. Dell’Aquila, F. Blaabjerg. Stability improvements of an LCLfilter based threephase active rectifier [C]// Power Electronics Specialists Conference, PESC 2002, 3: 11951201.]，為超前網(wǎng)絡(luò)參數(shù)的選擇提供了一定的參考。此外，Marco Liserre又提出了基于雙帶通濾波器的方法[M. Liserre, A. Dell’Aquila, F. Blaabjerg. Genetic algorithmbased design of the active damping for an LCLfilter threephase active rectifier.[J]. IEEE Trans. on Power Electronics, 2004, 19(1): 7686.]，該方法不需要額外的傳感器。但是采用的遺傳算法增加了控制系統(tǒng)的復(fù)雜程度，目前在工業(yè)上還很難得到應(yīng)用。從實(shí)際的角度即工業(yè)應(yīng)用的角度來(lái)看，有源阻尼有一些缺點(diǎn)，Pekik Argo Dahono提出的“虛擬電阻”需要增加電容電流傳感器；，增加了系統(tǒng)的造價(jià)，此外這種方法需要配置增益和零點(diǎn)、極點(diǎn)，有三個(gè)參數(shù)需要調(diào)節(jié)，設(shè)計(jì)過(guò)程比較復(fù)雜，不太適合工程設(shè)計(jì)；Marco Liserre用遺傳算法來(lái)調(diào)節(jié)系統(tǒng)，不需要增加傳感器，但復(fù)雜了控制算法。因而，與普通帶L濾波器的并網(wǎng)逆變器相比，增加了傳感器的數(shù)量，也就增加了系統(tǒng)的成本，并降低了運(yùn)行的可靠性。為此，研究減少傳感器數(shù)量的控制策略很有必要。文獻(xiàn)[M. Malinowski, W. Szczygiel, M. Pkazmierkowski, et al. Sensorless operation of active damping method for threephase PWM conveters [C]// Industrial Electronics, 2005. ISIE 2005. Proceeding