船舶柴油机转速的线性自抗扰控制

船舶柴油机推进系统包含非线性、时变参数以及柴油机-推进轴系-螺旋桨之间的强耦合作用，难以建立精确的数学模型，且易受到螺旋桨负载扰动的影响，不利于船舶柴油机转速的实时准确控制。针对此问题，将线性自抗扰控制（Linear Active Disturbance Rejection Control，LADRC）技术应用于船舶柴油机的转速控制系统。首先，基于平均值建模方法建立了某大型低速二冲程船舶柴油机的模型，并分析了转速控制中的不确定因素；然后，针对柴油机的转速控制问题设计了二阶LADRC控制器；最后，以船舶柴油机平均值模型为载体对LADRC的控制性能进行仿真测试，并与经过遗传算法优化的PI控制器进行对比。仿真结果表明，在负载扰动及模型参数改变的情况下LADRC表现出良好的控制性能，并且比PI控制具有更优的扰动抑制能力和鲁棒性。

Linear Active Disturbance Rejection Control forMarine Diesel Engine

Marine diesel engine propulsion system contains nonlinearity, time-varying parameters and strong coupling between engine, propulsion shaft and propeller, which is difficult to develop an accurate mathematic model and vulnerable to propeller load disturbance. All of these factors work to the disadvantage of the real-time and accurate control of engine speed. For addressing this problem, linear active disturbance rejection control (LADRC) technique was applied to the speed control system of a marine diesel engine. Firstly, the mathematical model of a large slow-speed two-stroke marine diesel engine was developed using a mean value modelling approach, and the uncertainties in the speed control system were analyzed; secondly, a second-order LADRC controller was designed for the target engine; finally, the performance of the LADRC was tested based on the developed mean value engine model and compared with PI controller optimized using genetic algorithm. Simulation results showed that the LADRC controller exhibited good performance under the conditions of load disturbance and model parameter variation, and LADRC was superior to the PI controller in disturbance rejection performance and robustness.