针对传统扰动观察法在光伏系统最大功率点跟踪(Maximum Power Point Tracking,MPPT)中存在步长选取不能同时兼顾跟踪速度及稳态精度的问题,在可变工作环境下建立起光伏系统最大功率点电压与环境温度和光照强度之间的数学表达式,获得可...针对传统扰动观察法在光伏系统最大功率点跟踪(Maximum Power Point Tracking,MPPT)中存在步长选取不能同时兼顾跟踪速度及稳态精度的问题,在可变工作环境下建立起光伏系统最大功率点电压与环境温度和光照强度之间的数学表达式,获得可变环境下光伏系统最大功率点电压值,再将其赋值给小步长扰动观察法。仿真分析结果表明,相比恒定电压-扰动观察法,所提方法具有更快跟踪速度和更高稳态精度。展开更多
针对光照强度不均匀造成光伏阵列的输出曲线为多峰曲线,传统最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制算法不能跟踪到全局最大功率的问题,文章提出一种基于改进麻雀搜索算法(Improved the Sparrow Search Algorithm,ISSA...针对光照强度不均匀造成光伏阵列的输出曲线为多峰曲线,传统最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制算法不能跟踪到全局最大功率的问题,文章提出一种基于改进麻雀搜索算法(Improved the Sparrow Search Algorithm,ISSA)和扰动观察法(Perturbation and Observation Method,P&O)的光储发电系统MPPT控制方法。首先,在跟踪前期,采用混沌映射方式增加ISSA种群多样性,提升算法广泛搜索能力。为了防止算法陷入局部最优,利用萤火虫扰动算法对麻雀个体进行扰动更新;其次,在跟踪后期,使用P&O防止系统在最大功率点附近振荡,保证最大功率点稳定输出;最后,经过算例分析,所提MPPT控制方法实现了不同场景下的快速跟踪、精准输出,能够很好应用地于光储混合发电系统中。展开更多
As photovoltaic energy increasingly penetrates in power systems,transmission system operators have started to request its participation in providing ancillary services.One of the demanded services is the power ramp-ra...As photovoltaic energy increasingly penetrates in power systems,transmission system operators have started to request its participation in providing ancillary services.One of the demanded services is the power ramp-rate control(PRRC),which attempts to limit the power ramps produced by intermittent irradiance conditions.In order to achieve the desired objective,solutions based on storage systems or modifying the maximum power point tracking(MPPT)in perturb and observe(P&O)algorithms are commonly adopted.The starting point in PRRC is the determination of the instantaneous power ramprate,and different methods have been proposed in the literature for its calculation.However,the accuracy and computational speed of existing procedures can be improved,which may be critical in situations with rapid irradiance fluctuations.In this paper,a decoupled photovoltaic power ramp-rate calculation method is presented,in which the effect of variable irradiance and the P&O algorithm are computed separately.The proposed method has been theoretically demonstrated and tested through simulation and experimental tests.Simulation results show that it can improve the previous methods in terms of accuracy and computation time.Experimental validation with hardware-inthe-loop demonstrates the suitability of the proposed method for real-time applications,even in presence of noisy measurements.展开更多
The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design ...The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design method is proposed,considering satellite imaging width,formation flying of subgroup satellites,and global uniform coverage by payloads.Firstly,a configuration of satellites with the same subsatellite trajectory is proposed,and its orbital analytical expression under J2 perturbation is provided.Then,the relative motion feature points are extracted near the orbit of each satellite,and a group of uniform natural accompanying satellites are set to corresponding points.Afterwards,the orbit parameters of satellite and its companions are set as initial values,and the precise orbits under the High Precision Orbit Propagator model are solved in the neighborhood by using the Nondominated Sort Particle Swarm Optimization algorithm.Finally,the correctness of the configuration design method is verified by numerical simulation.展开更多
光伏发电系统效率优化关键在于最大功率点跟踪(maximum power point tracking,MPPT)控制技术,传统算法在环境变化及部分阴影下存在局限。对此,设计了模糊逻辑控制策略与改进型变步长扰动观察法,后者通过自适应步长调节和双层搜索结构,...光伏发电系统效率优化关键在于最大功率点跟踪(maximum power point tracking,MPPT)控制技术,传统算法在环境变化及部分阴影下存在局限。对此,设计了模糊逻辑控制策略与改进型变步长扰动观察法,后者通过自适应步长调节和双层搜索结构,标准测试条件下效率达99.3%。实验表明,该算法具备优越的动态响应、稳态精度和环境适应性,可为光伏系统高效运行提供技术支撑。展开更多
文摘针对传统扰动观察法在光伏系统最大功率点跟踪(Maximum Power Point Tracking,MPPT)中存在步长选取不能同时兼顾跟踪速度及稳态精度的问题,在可变工作环境下建立起光伏系统最大功率点电压与环境温度和光照强度之间的数学表达式,获得可变环境下光伏系统最大功率点电压值,再将其赋值给小步长扰动观察法。仿真分析结果表明,相比恒定电压-扰动观察法,所提方法具有更快跟踪速度和更高稳态精度。
文摘针对光照强度不均匀造成光伏阵列的输出曲线为多峰曲线,传统最大功率点跟踪(Maximum Power Point Tracking,MPPT)控制算法不能跟踪到全局最大功率的问题,文章提出一种基于改进麻雀搜索算法(Improved the Sparrow Search Algorithm,ISSA)和扰动观察法(Perturbation and Observation Method,P&O)的光储发电系统MPPT控制方法。首先,在跟踪前期,采用混沌映射方式增加ISSA种群多样性,提升算法广泛搜索能力。为了防止算法陷入局部最优,利用萤火虫扰动算法对麻雀个体进行扰动更新;其次,在跟踪后期,使用P&O防止系统在最大功率点附近振荡,保证最大功率点稳定输出;最后,经过算例分析,所提MPPT控制方法实现了不同场景下的快速跟踪、精准输出,能够很好应用地于光储混合发电系统中。
基金This work was supported by the Spanish National Research Agency Agencia Estatal de Investigacion(No.PID2019-108966RB-I00/AEI/10.13039/50110001-1033).
文摘As photovoltaic energy increasingly penetrates in power systems,transmission system operators have started to request its participation in providing ancillary services.One of the demanded services is the power ramp-rate control(PRRC),which attempts to limit the power ramps produced by intermittent irradiance conditions.In order to achieve the desired objective,solutions based on storage systems or modifying the maximum power point tracking(MPPT)in perturb and observe(P&O)algorithms are commonly adopted.The starting point in PRRC is the determination of the instantaneous power ramprate,and different methods have been proposed in the literature for its calculation.However,the accuracy and computational speed of existing procedures can be improved,which may be critical in situations with rapid irradiance fluctuations.In this paper,a decoupled photovoltaic power ramp-rate calculation method is presented,in which the effect of variable irradiance and the P&O algorithm are computed separately.The proposed method has been theoretically demonstrated and tested through simulation and experimental tests.Simulation results show that it can improve the previous methods in terms of accuracy and computation time.Experimental validation with hardware-inthe-loop demonstrates the suitability of the proposed method for real-time applications,even in presence of noisy measurements.
基金supported in part by the Fundamental Research Funds for the Central Universities(No.3072022JC0202).
文摘The configuration optimization design of Low Earth Orbit observation mega constellation in complex space environment is a nonlinear problem that is difficult to solve analytically.In this paper,a constellation design method is proposed,considering satellite imaging width,formation flying of subgroup satellites,and global uniform coverage by payloads.Firstly,a configuration of satellites with the same subsatellite trajectory is proposed,and its orbital analytical expression under J2 perturbation is provided.Then,the relative motion feature points are extracted near the orbit of each satellite,and a group of uniform natural accompanying satellites are set to corresponding points.Afterwards,the orbit parameters of satellite and its companions are set as initial values,and the precise orbits under the High Precision Orbit Propagator model are solved in the neighborhood by using the Nondominated Sort Particle Swarm Optimization algorithm.Finally,the correctness of the configuration design method is verified by numerical simulation.
文摘光伏发电系统效率优化关键在于最大功率点跟踪(maximum power point tracking,MPPT)控制技术,传统算法在环境变化及部分阴影下存在局限。对此,设计了模糊逻辑控制策略与改进型变步长扰动观察法,后者通过自适应步长调节和双层搜索结构,标准测试条件下效率达99.3%。实验表明,该算法具备优越的动态响应、稳态精度和环境适应性,可为光伏系统高效运行提供技术支撑。
