In steam turbine control and actuation, the steam control valve plays a key role in operability and reliability. The electrohydraulic regulating system for the steam control valve, usually called the servomotor, needs to be reliable and high performing under nonlinear excitation interference in actual conditions. Currently, electrohydraulic servo valve control technology is widely used in servomotors. Although this technology has good control performance, it still has some technical defects, such as poor antipollution ability, low energy efficiency, large volume size, and limited installation space. Aiming at the abovementioned technical shortcomings of electrohydraulic servo valve control technology, a servomotor-pump-hydraulic cylinder volume control scheme is proposed in this paper, forming a pump-controlled servomotor for the steam control valve. By analyzing the working principle of the pump-controlled servomotor position control in the steam control valve, the mathematical model of a pump-controlled servomotor for the steam control valve is established. The sliding mode variable structure control strategy is proposed, and the variable structure control law is solved by constructing a switching function. To verify the performance of the proposed control method, experimental research was conducted. The research results show that the proposed sliding mode variable structure control strategy has a good control effect, which lays the theoretical and technical foundation for the engineering application and promotion of pump-controlled servomotors for steam control valves and helps the technical upgrade and product optimization of steam turbines.

中文翻译：

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蒸汽控制阀的泵控伺服电机的位置控制研究

在蒸汽轮机的控制和致动中，蒸汽控制阀在可操作性和可靠性方面起着关键作用。蒸汽控制阀的电动液压调节系统（通常称为伺服电动机）在实际情况下在非线性激励干扰下需要可靠且高性能。当前，电动液压伺服阀控制技术已广泛用于伺服电动机。尽管该技术具有良好的控制性能，但仍存在一些技术缺陷，例如抗污染能力差，能源效率低，体积大，安装空间有限。针对电液伺服阀控制技术的上述技术缺陷，提出了一种伺服电机-泵-液压缸容积控制方案，形成用于蒸汽控制阀的泵控制伺服电机。通过分析蒸汽控制阀中泵控伺服电机位置控制的工作原理，建立了蒸汽控制阀泵控伺服电机的数学模型。提出了滑模变结构控制策略，通过构造开关函数来求解变结构控制律。为了验证所提出的控制方法的性能，进行了实验研究。研究结果表明，所提出的滑模变结构控制策略具有良好的控制效果，