| 题名 | 太阳能跟踪伺服系统非线性特性及补偿研究 |
| 作者 | 姜春霞 |
| 学位类别 | 博士 |
| 答辩日期 | 2015-05 |
| 授予单位 | 中国科学院大学 |
| 导师 | 陈娟 |
| 关键词 | 太阳能跟踪 执行电机非线性 摩擦非线性 滑膜控制 补偿 |
| 其他题名 | The Research of Nonlinear Characteristics and Compensation Based on Solar Tracking Servo System |
| 学位专业 | 机械电子工程 |
| 中文摘要 | 太阳能是可再生能源之一，光伏发电是利用太阳能的方式之一。提高太阳能接收效率的最好方法是太阳能电池板实时和太阳光线保持垂直的自动跟踪技术。跟踪精度及稳定性是评价跟踪好坏的主要条件。 由于跟踪系统具有非常大的采光面，是一个转动惯量大的低速系统，角度调整是靠机械装置的传动机构完成，使得输出输入有偏差，影响太阳能跟踪伺服系统的跟踪精度。因此，研究太阳能跟踪伺服系统的非线性和有云层遮挡的闭环跟踪控制，对提高伺服系统的跟踪精度，具有重要的意义。 本论文首先论述了太阳能跟踪的基本理论，以基于三相混合式步进电机的双轴跟踪伺服系统为研究对象，分析影响跟踪稳定性和精度的因素，其主要包括混合式步进电机自身的非线性和执行机构的摩擦非线性。执行电机的非线性主要指其在运行过程中存在失步问题，对此问题提出解决方案，采用闭环控制的轴线定向空间矢量控制细分方法，采用滑模观测器的变结构控制代替机械传感器，估计转子的位置和速度，从而完成电机的无位置传感器控制，检测到的速度或位置信号反馈至控制电路，控制相应的功率器件通断。仿真验证所选择方法的合理性，解决失步问题。 对于跟踪控制系统的机械装置而言，摩擦非线性是主要因素。摩擦扰动对伺服执行机构的低速性能有很大影响，引起系统运行不稳定，产生低速抖动或爬行。由于太阳能跟踪伺服系统多数情况下工作在户外，环境变化大，采用不基于摩擦模型的补偿方法，建立考虑摩擦扰动的跟踪伺服系统数学模型，采用滑模扰动观测器和滑模控制器复合控制来补偿伺服系统的摩擦扰动，并且用李雅普诺夫函数证明系统稳定性，仿真验证算法的有效性，实现摩擦的补偿。 为了保证在云遮挡的天气中采用视日运行轨迹跟踪与图像处理的双模式跟踪闭环控制的运行精度和可靠性，提出一种提取太阳质心的算法。去除太阳图像中雾霾的方法采用中值滤波的快速暗通道去雾法，并进行指数增强，使用快速最大稳定特征区域(MSER)提取算法提取太阳区域，最后计算出太阳质心。实验验证所提的算法适用于复杂的天气条件，在雾霾天气下能够较为准确地提取太阳质心，保证了闭环跟踪控制的跟踪精度。 |
| 英文摘要 | Solar energy is one of the ideal renewable energy. Photovoltaic power generation is one of the ways to use solar energy。 The best way to improve the receiving efficiency of solar energy is automatic tracking technology which the solar battery board in real-time and the sun’s rays remain perpendicular. The main conditions of which evaluate the track- ing quality are tracking accuracy and stability. Since the tracking system with a very large light-receiving face is the system of very big, a low speed, big moment of inertia. The adjustment of angle is by means of a mechanical transmission mechanism a transmission mechanical device .The angle adjustment is accomplished by a mechanical device, the output and the input has deviation and affect the accuracy of the solar tracking system. So the rese- arch nonlinear of solar tracking servo system and a closed-loop tracking control in the cloud weather which improve the tracking accuracy of the servo system has important significance. First of all, the basic theory of the solar tracking servo is discussed in the paper. Two-axis tracking servo system of based on three-phase hybrid stepper motor is as the object of study, Analysis of the factors affecting the stability and precision of tracking. It include the nonlinear of hybrid stepping motor and friction nonlinear actuator. The main non-linear actuating motor is out of step problem whose existence during the operation, propose a solution to the problem by using closed-loop control mode which is based on subdivision axis orientation of space vector control, using sliding mode variable structure observer control instead of mechanical sensors, the position and speed of the rotor are estimated to complete the motor position sensorless control, the speed or position of detected signal feedback to logic control circuitry in order to determine the corresponding phase power device on-off. The method which is chosen to solve the problem of out of step is verified the reasonableness by simulation results. For tracking control system mechanical devices, friction nonlinear is a major factor. Friction disturbance have a great effect on the low-speed performance of the servo actuator and cause the system to run unstable, generating low jitter or crawling. Since solar tracking servo system can work in the outdoor environment in most cases which a relatively large changes in the environment, use the compensation method of not based on friction model and establish of a mathematical model considering friction disturbance of tracking servo system, use the compound control of sliding disturbance observer and sliding mode controller to compensate for friction disturbances of the servo system and demonstrate the stability of the system using the Lyapunov function, the effectiveness of the algorithm is verified by the simulation. In order to ensure the accuracy and reliability of the tracking servo system that adopt the day trajectory and the image processing of the dual mode track- ing closed-loop control method which is running in the cloud weather obscured the weather, and proposes an algorithm for extraction of sun centroid . Defogging method based on median filter to remove the fast channel solar image in the dark haze and enhanced index using a fast maximum stable feature regions (MSER) extraction algorithm to extract the solar area, finally calculate the centroid of the sun. Experimental verification of the proposed algorithm for complex weather conditions is verified by experiment, it can accurately extract the centroid of the sun in the fog and haze which ensure tracking accuracy of the closed-loop tracking. |
| 公开日期 | 2015-12-24 |
| 内容类型 | 学位论文 |
| 源URL | [http://ir.ciomp.ac.cn/handle/181722/48846]  |
| 专题 | 长春光学精密机械与物理研究所_中科院长春光机所知识产出 |
| 推荐引用方式 GB/T 7714 | 姜春霞. 太阳能跟踪伺服系统非线性特性及补偿研究[D]. 中国科学院大学. 2015. |
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