摘要
针对变量柱塞泵全寿命周期内出现的磨损、阻尼变化等因素导致的性能劣化问题,提出了一种基于数字孪生的变量柱塞泵云端优化控制方法,以实现泵在全寿命周期内保持良好的控制性能。首先,比例变量柱塞泵的控制模型采用基于状态控制的LQ最优控制(Linear Quadratic Optimal Control),该模型分别布置到云服务器和泵端嵌入式控制器中。然后,泵端嵌入式控制器在进行实时控制的同时也定时将采集到的传感器参数以及模型中的状态参数送至云服务器,云服务器保存泵的目前及历史数据,并基于遗传算法定期进行柱塞泵控制参数的优化。最后,云服务器将模型参数和定期优化获得的控制参数再发送至泵端嵌入式控制器,从而实现了云端与泵端模型的孪生,且在全寿命周期内模型随柱塞泵的状态而变,不仅可反映泵的当前状态,而且LQ控制器与泵的当前状态相适应可将泵的性能维持在最佳状态。以柱塞泵油温导致的阻尼变化为研究对象,进行了仿真研究。结果表明,当温度导致系统阻尼变化时,所提方法可使流量阶跃响应超调量始终保持在0.5%以下,与固定参数的方法相比,超调量降低了89%~96%。结合参数优化控制实验结果,验证了所提基于数字孪生模型的云端优化控制方法的有效性。
In order to improve the performance of variable piston pump in its whole operation cycle,a cloud-based optimization control method based on digital twin was proposed to solve the problem of performance deterioration caused by wear and damping change in the operation process.Firstly,a LQ optimal control method based on state control was used as the control model of proportional variable piston pump,which was arranged in cloud server and pump embedded controller respectively.Then the pump embedded controller was responsible for real-time control and sent the parameters collected by sensors and the state parameters to the cloud server.The cloud server saved the current and historical data of the pump and optimized the control parameters of the piston pump based on genetic algorithm.Finally,the cloud server periodically sent the mode parameters and the optimized parameters to the pump-side embedded controller to achieve the twin of cloud and pump side model,which can not only reflect the current state of the pump,but also maximize its performance.By using the proposed method,the influence of damping change caused by oil temperature on pump control performance was simulated.The results show that the proposed method can keep the overshoot of flow step response below 0.5%when the system damping changes due to temperature.Compared with the method with fixed parameters,the overshoot was reduced by 89%~96%.Combined with the experimental results of parameters optimization,the effectiveness of the proposed cloud-based control method based on digital twin is verified.
作者
张宁宁
李雅慧
赵国强
郑戍华
王向周
ZHANG Ning-ning;LI Ya-hui;ZHAO Guo-qiang;ZHENG Shu-hua;WANG Xiang-zhou(School of Automation,Beijing Institute of Technology,Beijing 100081,China)
出处
《液压气动与密封》
2022年第12期1-6,13,共7页
Hydraulics Pneumatics & Seals
基金
国家重点研发基金项目(2018YFB2001101)。
关键词
变量柱塞泵
数字孪生
全寿命周期
LQ优化控制
variable piston pump
digital twin
whole operation cycle
LQ optimal control
