徐濱全 王元東 宋程
摘? 要:文章首先根據(jù)高速動(dòng)車組網(wǎng)絡(luò)控制系統(tǒng)的結(jié)構(gòu)建立前向通道時(shí)延及反饋通道時(shí)延的多功能車輛總線網(wǎng)絡(luò)控制系統(tǒng)。然后基于T-S模糊模型建立非線性網(wǎng)絡(luò)控制系統(tǒng)模型,設(shè)計(jì)各子系統(tǒng)基于狀態(tài)空間滾動(dòng)優(yōu)化的廣義預(yù)測(cè)控制(Generalized Predictive? Control,GPC)算法,但傳統(tǒng)的GPC算法在線計(jì)算量大,不能保證高速動(dòng)車組網(wǎng)絡(luò)控制的實(shí)時(shí)性,故文章提出了一種改進(jìn)的GPC算法,利用GPC算法與動(dòng)態(tài)矩陣控制律的等價(jià)性直接求解最優(yōu)控制,可極大地減少計(jì)算量。最后分別采用不考慮時(shí)延的基于T-S模糊模型GPC控制方法、基于T-S模糊模型GPC時(shí)延控制方法及基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法進(jìn)行實(shí)驗(yàn)仿真。實(shí)驗(yàn)結(jié)果表明:采用基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法優(yōu)于其它兩種控制方法,該方法可精確地跟蹤參考方波信號(hào),也能較好地抑制時(shí)延對(duì)控制性能的影響且動(dòng)車組制動(dòng)開(kāi)始時(shí)速度輸出的滯后時(shí)間非常短、無(wú)劇烈的震蕩輸出,故保證了高速動(dòng)車組網(wǎng)絡(luò)控制的實(shí)時(shí)性。
關(guān)鍵詞:高速動(dòng)車組;T-S模糊模型;GPC算法;多功能車輛總線;時(shí)延
中圖分類號(hào):U285? ? ? ? ? 文獻(xiàn)標(biāo)志碼:A? ? ? ? ?文章編號(hào):2095-2945(2020)17-0122-04
Abstract: In this paper, a multifunctional vehicle bus network control system with forward channel delay and feedback channel delay is established according to the structure of high-speed EMU network control system. Then, the nonlinear networked control system model is established based on the T-S fuzzy model, and the generalized predictive control (GPC) algorithm for each subsystem based on state space rolling optimization is designed. But the traditional GPC algorithm has a large amount of online calculation and can not guarantee the real-time performance of the networked control of high-speed EMU, so this paper proposes an improved GPC algorithm, which uses the equivalence of the GPC algorithm and the dynamic matrix control law to solve the optimal control directly, thereby can greatly reduce the amount of calculation. Finally, the experimental simulation is carried out by using the GPC control method based on T-S fuzzy model without considering time delay, the GPC time delay control method based on T-S fuzzy model and the improved GPC time delay control method based on T-S fuzzy model. The experimental results show that the improved GPC time delay control method based on T-S fuzzy model is better than the other two control methods. This method can not only accurately track the reference square wave signal, but also restrain the influence of time delay on the control performance. The lag time of speed output at the beginning of EMU braking is very short and there is no severe vibration output, so it ensures the real-time performance of high-speed EMU network control.
Keywords: high-speed EMU; T-S fuzzy model; GPC algorithm; multifunctional vehicle bus; time delay
1 概述
列車通信網(wǎng)絡(luò)(TrainCommunicationNet,TCN)作為列車控制系統(tǒng)的關(guān)鍵部位,所有的控制信號(hào)都通過(guò)列車總線(Wire Train Bus,WTB)與多功能車輛總線(Multifunction Vehicle Bus,MVB)傳送至相應(yīng)的執(zhí)行單元[1]。近年來(lái),國(guó)內(nèi)外已開(kāi)始關(guān)注網(wǎng)絡(luò)時(shí)延與列車通信網(wǎng)絡(luò)控制算法的研究,因?yàn)榱熊嚳刂葡到y(tǒng)具有非常復(fù)雜的非線性特性,故在控制與建模方面的研究難度非常高。由于T-S模糊模型可任意精度逼近非線性模型且其參數(shù)受影響的程度較小,故已被大規(guī)模地應(yīng)用于非線性網(wǎng)絡(luò)控制系統(tǒng)之中。本文搭建基于MVB的網(wǎng)絡(luò)控制系統(tǒng)、考慮系統(tǒng)時(shí)延并采用T-S模糊模型對(duì)非線性系統(tǒng)建模,為各子線性系統(tǒng)設(shè)計(jì)廣義預(yù)測(cè)控制器。最后,通過(guò)實(shí)驗(yàn)仿真來(lái)驗(yàn)證上述方法的正確性與有效性。
2 高速動(dòng)車組網(wǎng)絡(luò)控制系統(tǒng)
高速動(dòng)車組通信網(wǎng)絡(luò)控制系統(tǒng)包含一個(gè)顯示屏(HumanMachin Interface,HMI)和兩個(gè)中央控制單元(Central Control Unit,CCU)且都以過(guò)程數(shù)據(jù)在MVB上通信[2]。用CCU-1作為控制器節(jié)點(diǎn)對(duì)牽引、制動(dòng)系統(tǒng)進(jìn)行控制,通過(guò)組態(tài)軟件把控制算法嵌入CCU-1之中,根據(jù)傳感器節(jié)點(diǎn)檢測(cè)的最新數(shù)據(jù)將控制量計(jì)算出來(lái),再傳輸給執(zhí)行器節(jié)點(diǎn)CCU-2并模擬制動(dòng)或牽引的執(zhí)行過(guò)程,之后把結(jié)果傳輸給傳感器節(jié)點(diǎn)。系統(tǒng)可通過(guò)HMI傳感器輸出信號(hào)的測(cè)量結(jié)果并傳輸給CCU-1。故高速動(dòng)車組網(wǎng)絡(luò)控制系統(tǒng)的傳輸時(shí)延包括執(zhí)行器節(jié)點(diǎn)與控制器節(jié)點(diǎn)之間的前向通道時(shí)延τca和控制器節(jié)點(diǎn)與傳感器節(jié)點(diǎn)之間的反饋通道時(shí)延τsc,整個(gè)系統(tǒng)的網(wǎng)絡(luò)時(shí)延為τ=τca+τsc。MVB網(wǎng)絡(luò)控制系統(tǒng)結(jié)構(gòu)如圖1所示。
3 基于T-S模糊模型與改進(jìn)的GPC時(shí)延控制方法
4 實(shí)驗(yàn)與結(jié)果分析
本文將高速動(dòng)車組的制動(dòng)非線性系統(tǒng)作為研究的對(duì)象,系統(tǒng)的輸入與輸出分別為制動(dòng)力、高速動(dòng)車組的速度。分別采用不考慮時(shí)延的基于T-S模糊模型GPC控制方法、基于T-S模糊模型GPC時(shí)延控制方法及基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法進(jìn)行對(duì)比實(shí)驗(yàn)。采用MATLAB作為仿真軟件,首先創(chuàng)建包含5條模糊規(guī)則的T-S模糊模型,然后再設(shè)計(jì)5個(gè)廣義預(yù)測(cè)控制器,控制步長(zhǎng)M、預(yù)測(cè)步長(zhǎng)P、收斂因子μ及控制加權(quán)系數(shù)λ分別設(shè)置為3、20、0.1及0.1;選擇Z函數(shù)作為模糊隸屬度函數(shù)。跟蹤方波輸出響應(yīng)曲線如圖2與圖3所示。由圖2可知:當(dāng)采用不考慮時(shí)延的基于T-S模糊模型GPC控制方法時(shí),跟蹤信號(hào)每次跳變瞬間輸出劇烈的震蕩,一段時(shí)間后才穩(wěn)定且不能很快精確地跟蹤方波。當(dāng)采用基于T-S模糊模型GPC時(shí)延控制方法時(shí),制動(dòng)開(kāi)始時(shí)速度輸出滯后時(shí)間較長(zhǎng),但跟蹤信號(hào)能很快精確地跟蹤方波且無(wú)劇烈的震蕩輸出。由圖3可知:當(dāng)采用基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法時(shí),高速動(dòng)車組制動(dòng)開(kāi)始時(shí)速度輸出的滯后時(shí)間非常短,跟蹤信號(hào)也能較快精確地跟蹤方波且不超調(diào),無(wú)劇烈的震蕩輸出。綜上,基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法優(yōu)于其它兩種方法。
5 結(jié)束語(yǔ)
本文基于T-S模糊理論建立高速動(dòng)車組網(wǎng)絡(luò)控制模型,并對(duì)各線性子模型設(shè)計(jì)了廣義預(yù)測(cè)控制器進(jìn)行模糊加權(quán)控制,提出了一種改進(jìn)的GPC算法。實(shí)驗(yàn)結(jié)果表明:基于T-S模糊模型改進(jìn)的GPC時(shí)延控制方法可有效地控制時(shí)延、快速精確地跟蹤參考信號(hào)且高速動(dòng)車組制動(dòng)開(kāi)始時(shí)速度輸出的滯后時(shí)間非常短、無(wú)劇烈的震蕩輸出,保障了高速動(dòng)車組網(wǎng)絡(luò)控制的實(shí)時(shí)性與魯棒性。
參考文獻(xiàn):
[1]Yang T.Coupling onto radio frequency components enclosed within canonical structure[D].Adissertation for the Phd in the university of Michingan,2006.
[2]張曉晉,張順廣,黃楓.CRH3型動(dòng)車組旅客信息系統(tǒng)與列車網(wǎng)絡(luò)控制系統(tǒng)通信接口分析[J].鐵道機(jī)車車輛,2014,34(4):47-51.
[3]LI shu jiang,WUYing,WANG Xiang dong,et al.VAVTerminal Unitcontrol Based on-S Model With the Generalized PredictiveControl[J].Applied Mechanics and Materials,2013,303/304/305/306:1234-1237.
[4]倪銳.無(wú)線網(wǎng)絡(luò)的業(yè)務(wù)研究[D].中國(guó)科學(xué)技術(shù)大學(xué),2011.
[5]Cohn.Determination of aperture parameters by electro-lvtic tank measurements[J].IEE,1980(32):1416-1421.