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基于粒子群优化神经网络光伏并网最大功率点跟踪技术研究 总被引:1,自引:0,他引:1
针对电导增量法无法搜索全局光伏系统最大功率点的不足,文章将神经网络与电导增量法相结合,提出一种新型光伏并网最大功率点跟踪算法。该算法在不同光照和温度情况下,采集光伏阵列电压值和电流值,建立神经网络模型。通过人工神经网络预测光伏阵列输出电压,并将此电压作为电导增量法参考电压,从而实现局部阴影下最大功率点跟踪。实验结果表明,神经网络与电导增量法相结合可以准确实现局部阴影下光伏阵列最大功率点跟踪,具有较高的跟踪精度。 相似文献
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《可再生能源》2016,(9)
针对光伏系统传统的最大功率点跟踪(MPPT)算法跟踪速度慢、易振荡、跟踪精度低等不足,提出一种改进的分数阶电导增量(IFOINC)算法,即将基于功率预测的变步长扰动观察(PO)算法和分数阶电导增量(FOINC)算法结合使用。IFOINC算法具体跟踪过程,先采用基于功率预测的变步长PO算法快速跟踪到MPP附近,再采用FOINC算法进一步搜索MPP从而完成整个跟踪过程。文章研究了光伏系统结构,光伏电池的等效模型,设计了IFOINC算法,建立了光伏系统MPPT仿真模型,在Matlab/Simulink下进行仿真。在光照均匀的条件下,改变其它环境条件,研究IFOINC算法的MPP跟踪效果与基于功率预测的变步长PO算法和FOINC算法之间的差异。研究结果表明,IFOINC算法的跟踪速度比FOINC算法提高了42.3%,IFOINC算法的跟踪精度比基于功率预测的变步长PO算法提高了3.9%,且消除了跟踪过程的振荡。 相似文献
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利用传统电导增量法跟踪最大功率点时,若跟踪步长较大,则跟踪速度较快,但跟踪精度较差;反之,则跟踪精度较好,但跟踪速度较慢。当外界环境发生变化时,利用传统电导增量法得到的功率变化曲线振荡幅度较大,功率损失较多。改进粒子群算法能够对外界环境的突变迅速作出响应,利用该方法得到的功率变化曲线振荡幅度较小,但是很难精确地定位到最大功率点(MPP)。因此,文章提出一种混合控制的最大功率点跟踪(MPPT)策略,先利用改进粒子群算法快速跟踪到MPP附近,然后利用小步长电导增量法对MPP进行精细搜索。仿真结果表明,该跟踪策略在一定程度上能够增加跟踪系统的响应速度、跟踪精度,减小功率变化曲线的振荡幅度。 相似文献
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光伏系统的最大功率点跟踪方法可以最大限度地利用光伏电池所能产生的电能,因此成为提高光伏发电系统运行效率、降低光伏电能成本的研究热点。针对目前常用的扰动观察法速度较慢、电导增量法在最大功率点附近有较大振荡的问题,提出一种改进变步长电导增量的最大功率点跟踪控制方法,该方法既具有电导增量法快速跟踪的优点,又能准确、稳定地跟踪到最大功率点,因此更适于提高光伏电源的能源利用率。对所提方法进行了仿真分析,并比较了几种MPPT算法的跟踪效果,结果表明,所提方法具有快速性、稳定性和有效性。 相似文献
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针对光伏发电最大功率点跟踪(MPPT)技术的研究和发展现状,提出一种基于增量电导法的变步长MPPT算法。建立太阳电池参数模型,通过理论分析、Matlab仿真实验和实际实验验证,推导出一种基于增量电导法的变步长电压方程。该方程中步长电压ΔU关于输出电压U在太阳电池的[0.20U_(oc),0.93Uoc]区间具有近似直线特性,通过采集电压电流可解得ΔU-U的直线方程及其值为零时的输出电压Uref,进而再以Uref为起始电压、ΔU为步长电压采用增量电导法进行MPPT。实验结果表明,所提MPPT算法能快速精确跟踪到太阳电池的最大功率点。 相似文献
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Combining demand controlled ventilation (DCV) control and economizer control achieves acceptable and even better indoor air quality with minimum coil energy consumption. The control instability during the transition processes between different control modes are among the major difficulties faced when utilizing economizer control and when combining DCV control with economizer control in applications. A robust control strategy, using “freezing”, gain scheduling, integral term reset and feedback transition control for different transition processes, is developed for addressing these problems. They are evaluated on an air handling unit (AHU) using various simulation tests. The test results demonstrate that the robust control strategy allows stable and robust AHU control. 相似文献
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通过实例介绍了模糊控制以及复合模糊控制在直接转矩控制系统中的应用,并以永磁同步电机的模糊控制为例进行了仿真验证,提出了有待进一步解决的问题和发展前景。 相似文献
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The performance of an incremental Clarke-Gawthrop adaptive control scheme, suitable for a diesel-engine prime mover, is described. The controller uses a predictor that is derived from explicit estimates of the plant deadtime and time constants. Its performance under speed reference changes and load disturbances has been compared to that of a fixed, tuned proportional-integral (PI) controller. The algorithm is found to operate satisfactorily under different values of droop without any additional complexity of computation being incurred. However, the improvement in plant response due to the adaptive algorithm is somewhat reduced at high droops. The effective improvement due to adaptation is also seen to be reduced under `cold oil' conditions. However, even under such conditions, it is possible to obtain improved response as compared to the PI controller 相似文献
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In the last few years, there is a strong trend towards decentralised production and supply, leading to a situation where a growing number of small and medium size producers will be connected to energy networks. But at the same time, the power quality of the generation must be ensured and this means that the electrical parameters of the distribution network have to be maintained within their upper and lower limits. Therefore, new problems related to the management and operation of energy transfer and distribution and to the efficient distribution of renewable energy in the grids are actually arising. Hence, it is reasonable to think that dispersed generation (wind energy generation in this paper) should start to take part in the control of electric variables, and in particular, in reactive power control which is directly related to the voltage level control of distribution networks. This paper presents a control strategy developed for the reactive power regulation of wind farms made up with double fed induction generators, in order to contribute to the voltage regulation of the electrical grid to which farms are connected. 相似文献
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Mahdi Imanian Mahdi Karbasian 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(18):2193-2202
Proper well control is one of the most important challenges during drilling operations in the oil and gas industry. Engineering Process Control is employed to control bit pressure in the present study. As the main innovation in this study, the reference tracking scenario is utilized for the first time to find the extent to which the controllers can track bit pressure by modifying the reference pressure of different formations in the course of the drilling operation. Overall, the model reference adaptive control is shown to perform better in controlling bit pressure according to some features including the process output tracking criteria, control effort, controller tracking error, and cost functions, in comparison to other controllers. 相似文献
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