【作者】 陈炜；

【导师】 杨永滨；

【作者基本信息】 哈尔滨工业大学 ， 动力机械及工程， 2008， 硕士

【摘要】 船用的蒸汽动力装置是船舶的主要设备,在其运行过程中,负荷变化频繁、幅度大,对系统的响应性能要求高,而其中的机炉系统控制则是蒸汽动力装置控制中的一个难点。由于其具有非线性、强耦合、参数时变、大迟延等特性,采用常规的控制策略往往不能满足系统的要求。因此锅炉与汽轮机在运行过程中,特别是大变工况过程中要兼顾船舶安全性和快速性,两者的协调控制显得尤为重要。本文在分析了机炉系统动态特性模型的基础上,对其进行控制方法研究。本文首先根据船用蒸汽动力装置复杂的气动热力过程分别建立了船舶锅炉模型和汽轮机电液控制系统非线性模型。接着进行了仿真计算,从机理上分析所得模型的正确性。由此得到的船用蒸汽动力装置非线性模型是分析机组特性、研究其控制规律、并对控制系统进行设计和仿真的基础。其次,在现有的船舶蒸汽动力装置的控制方案的基础上,本文采用了锅炉侧采用直接能量平衡(DEB)控制方法的锅炉跟随汽轮机的控制系统。接着分析了DEB控制系统的物理规律。然后通过仿真得出船用蒸汽动力装置在大范围变工况和小范围变工况时的各个参数动态响应,最后提出了船用蒸汽动力装置在大范围变工况时的安全性和快速性之间的矛盾。船用蒸汽动力装置运行时,工况经常大范围变化的快速响应与安全性之间的矛盾,决定船用蒸汽动力装置控制的特殊性。为此论文在结合船舶蒸汽动力装置的安全运行要求的基础上,论述了船舶蒸汽动力装置的调节/保护的基本思想,给出了船用蒸汽动力装置调节/保护的控制结构,并提出了一种基于Max/Min的切换规则并在此基础上设计PI控制器,最后分析了基于Max/Min的切换规则的存在的问题,给出了解决的方法。最后通过仿真验证了—基于切换控制的船用蒸汽动力装置调节/保护的控制方法能够较好的解决船用蒸汽动力装置工况大范围变化时的快速响应与安全性之间的矛盾。为满足船舶在紧急工况下的安全性和快速性的统一,根据船用汽轮机的特点—存在倒车汽轮机,提出了结合正倒车汽轮机协调控制的方法,最后通过仿真计算验证了正倒车协调方法的有效性。更多还原

【Abstract】 Ship steam power equipment is one of the most important equipments of ship. when it was running, the loads varied frequently, and the varying range is big. So it required a high response performance for the system. Furthermore, the boiler-turbine control is one difficulty of the steam power equipment control. Because the characters of nonlinear, strong coupling, time-vary and big delay, routine control strategy can’t satisfy the requirements of the system. It is important for both to be coordinated better during the operation of the boiler and the turbine, especially off-design working condition. Based on the analysis of the dynamic characters of the boiler-turbine system, this dissertation researched the mathematic modeling and control of the coordinated system.First, establish the nonlinear model of the boiler-turbine by it’s complex thermodynamic process which include improving the existed thermodynamic model of the boiler and establishing the Digital Electro-Hydraulic control of model. In nature, it is a two-input and two-output of the nonlinear characteristics model. Then we do a series of simulation calculation using this model, and validate the correctness of the model from the side of physics. Analyze the model characteristic, research its control law, and design the controller system are on the basis of the nonlinear components model. The components model also the basis to establish real-time model and expansion the research of performance parameters.Based on analyzing two basic schemes—boiler followed turbine and turbine followed boiler in the traditional boiler-turbine control system, this dissertation expatiated the principle of coordinated control system and given its structure diagram. Then we use the control strategy of boiler followed turbine. The DEB (Direct Energy Balance) control scheme, which is now widely in practice, is able to realize the thought of Gain Scheduling and Static decoupling, partially neutralize the nonlinearity of the system Then we give dynamic response of every parameter in the small and big loads varying.The paper considered the control problems of ship steam power equipment and the contradiction between the high maneuverability and safety due to the big loads varying frequently. The paper analyzed the control tasks, safe boundaries during working, the boiler-turbine working conditions. And the paper expounded the multi-objective control problem is a multi-model control problem, and proposed the multi-loop control system in structure, and according to the Max/Min switching strategy to control. Then we design the PI control system. Based on this switching strategy, analyze the problem of switching strategy and give the solution of the problem. Finally, we validate the correctness of the model by simulation calculation.Moreover, according to the properties of ship main turbine it has reverse turbine. In order to meet the combination of control strategy on the safety and flexibility, we propose a feasible solution to advance and reverse conditions. Finally, we validate the correctness of the model by simulation calculation.更多还原