冲击式水轮机喷针同步控制系统研究

发布时间：2018-06-14 19:12

本文选题：冲击式水轮机 + 喷针　；参考：《哈尔滨工业大学》2014年硕士论文

【摘要】：冲击式水轮机中导流机构性能直接决定了水斗的来流特性，对水轮机的水力效率和运行寿命有重要影响,在冲击式水轮机试验台喷针系统设计课题中,对导流机构喷嘴中喷针的同步控制进行了研究。为了提高系统位置控制精度和自动化水平，首次在喷针控制系统中使用电液伺服控制技术代替传统机械控制方式。多液压缸系统的位移同步控制是现代电液伺服系统研究中的重难点，基于改善多喷针位置调节过程中同步特性的目的，本系统借鉴了电机同步中耦合控制策略，通过仿真和试验探究了相邻交叉耦合、环形耦合及其与模型参考自适应算法相结合时对系统同步控制的提升。针对非对称缸系统正反向动态特性差异，本文中分别建立了电液伺服系统模型，，在此基础上利用Z变换、差分方程得到伺服系统离散控制模型；喷针的位移调节要求高位置精度，对控制器设计提出了较高要求，本设计中应用PID遗传算法优化的方式整定PID控制器参数，提高单一回路系统性能；同步控制策略上，将多电机位移同步控制中采用耦合策略移植到液压伺服同步控制系统中，通过LabVIEW软件进行系统仿真，研究了算法特性；为了进一步改善系统对阶跃信号响应同步控制精度以及控制过程的稳定性，设计了模型参考自适应控制器（MRAC），并将MRAC与耦合算法相结合在一定程度上改善了系统同步性能。在哈尔滨电机厂冲击式水力试验台对喷针同步控制系统进行了试验研究，试验结果验证了耦合同步策略控制下系统同步性能大幅提升的仿真结果；分析对比耦合同步策略及其与模型参考自适应算法相结合时系统的同步特性，MRAC相邻交叉耦合控制器拥有最优的控制效果，其阶跃响应同步偏差减小至原始系统的26.7%，多频率正弦信号响应均小于原始系统的16.7%，偏差信号标准差减小，系统控制稳定性增强。研究结果表明模型参考自适应相邻耦合控制算法对本伺服系统同步性能优化效果明显，位置同步精度、控制稳定性等指标都有不同程度的提升，达到使用要求，保证了多喷针调节过程的精确同步控制。
[Abstract]:The performance of the diversion mechanism in the impinging turbine directly determines the characteristics of the inlet flow of the bucket, and has an important effect on the hydraulic efficiency and operation life of the turbine. In the design project of the injection needle system of the impact-type hydraulic turbine test bed, The synchronous control of injection needle in nozzle of diversion mechanism is studied. In order to improve the precision and automation of the system position control, the electro-hydraulic servo control technology is used to replace the traditional mechanical control method in the injection needle control system for the first time. The displacement synchronization control of multi-cylinder system is a difficult point in the research of modern electro-hydraulic servo system. Based on the purpose of improving the synchronization characteristics in the process of multi-injection needle position adjustment, the system uses the coupling control strategy in motor synchronization for reference. By simulation and experiment, this paper explores the improvement of the synchronization control of the system when the adjacent cross-coupling, the ring coupling and the model reference adaptive algorithm are combined together. Aiming at the difference of the positive and backward dynamic characteristics of the asymmetric cylinder system, the electro-hydraulic servo system model is established in this paper, and the discrete control model of the servo system is obtained by using the Z transform and the difference equation. The displacement adjustment of the injection needle requires high position precision, and puts forward a higher requirement to the controller design. In this design, the pid controller parameters are optimized by using pid genetic algorithm to improve the performance of the single loop system. The coupling strategy is transplanted to the hydraulic servo synchronous control system in the multi-motor displacement synchronization control system. The system simulation is carried out by LabVIEW software, and the algorithm characteristic is studied. In order to further improve the synchronization control accuracy and the stability of the control process, a model reference adaptive controller (MRAC) is designed, and the synchronization performance of the system is improved to a certain extent by combining MRAC with the coupling algorithm. The synchronous control system of injection needle was tested on the impact hydraulic test bench of Harbin Electric Machinery Factory. The simulation results of the synchronization performance of the system under the coupled synchronization strategy were verified. This paper analyzes and compares the synchronization characteristics of the system with the coupled synchronization strategy and its combination with the model reference adaptive algorithm. The MRAC adjacent cross-coupling controller has the optimal control effect. The synchronous deviation of the step response is reduced to 26.7b of the original system, and the multi-frequency sinusoidal signal response is smaller than the original system's 16.7. the deviation signal standard deviation is reduced, and the control stability of the system is enhanced. The results show that the model reference adaptive adjacent coupling control algorithm can improve the synchronization performance of the servo system to some extent, such as the precision of position synchronization and the stability of control. The accurate synchronization control of the multi-injection needle adjustment process is ensured.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TK735

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