考虑电池性能的独立光储系统能量管理策略

为满足含混合储能的独立光伏发电系统的安全、稳定运行要求,延长光储系统的使用寿命,提出一种能量管理策略.该策略对光储系统的工作模式进行分类,并对不同的工作模式采用不同的控制电路,在维持母线电压稳定的基础上,增加了并联电池组的功率分配控制;通过引入虚拟下垂电阻实现多并联DC/DC变换器的控制;综合考虑电池的荷电状态、容量以...     

基于紧急功率支援的直流输电系统研究

VSC-HVDC通过利用全控期间的电压源型换流器,在一定程度上,克服了传统直流输电的不足之处,同时实现了有功功率和无功功率的独立控制。本文通过在仿真软件PSCAD/EMTDC中搭建了基于电压源型换流器的三端直流输电系统,并设计采用了改进型PID控制算法与功率支援模块用以快速改变直流线路传输功率,通过动态电流限幅环节抑制交流侧故障过电流,针对逆变器交流侧的几种常见故障和直流线路故障时系统的运行状况进行了仿真分析,并对不同的故障设计了不同的运行方案,仿真结果表明该系统在多种故障情况下均能够有效的保持系统频率与电压的稳定。     

四足机器人动步态下实时足底力优化方法的设计与验证

为实现四足机器人在动步态下的稳定行走及最优足底力分配,提出了融合全尺寸虚拟模型和动力学模型的四足机器人控制框架.在支撑相中,将躯干质心虚拟力与足底力分配问题转化成二次型优化问题,通过Gurobi库求最优值,实现实时的最优足底力分配.在摆动相中,融合动力学前馈和虚拟模型控制方法实现了平滑的轨迹追踪.通过Webots动力学仿真,将该方法与基本的位置阻抗控制方法在四足机器人平台上进行了对比分析,结果证明该方法能减小大约30%的足地交互冲击力,同时有效提高了机器人在运动中的稳定性.     

微网超级电容器储能系统的滑模控制策略研究

为改善微网运行不稳定的问题,针对与微网连接的超级电容器组储能装置的控制策略进行研究.储能装置由超级电容器组通过双向DC/DC变换器连接DC/AC变换器,通过滤波、升压后连入电网.通过对双向DC/DC转换器滑模控制的研究,使得任意操作条件均能正常工作,同时对运行中的稳定性进行了分析.最后,在Matlab中Simulink搭建储能系统仿真模型,验证了本文控制策略的可行性.     

Current‐mode control of DC–DC power converters: a backstepping approach

Current‐mode control is a robust industrial DC–DC power converter control scheme that has been successfully tested, is widely accepted, and is commonly implemented with conventional linear P and PI controllers. The need of more systematic designs with enhanced performance has motivated recent studies with linear and nonlinear advanced techniques, but the rigorous understanding and substantiation of the underlying key robust functioning capability are still lacking. In this paper, a constructive control approach is employed to study the current‐mode control problem of a class of DC–DC power converters, yielding a cascade control design methodology with: a robust convergence criterion coupled with a systematic and transparent construction‐tuning procedure, a rationale to explain the robust controller functioning, and a unified framework to interpret and compare the proposed controller with the existing conventional and advanced control designs. The implementation and functioning of the proposed control design is illustrated experimentally with a boost converter. Copyright © 2003 John Wiley & Sons, Ltd.     

独立光伏系统中蓄电池充电控制策略

在光伏系统中, 储能蓄电池达不到其使用寿命是制约光伏产业发展的一个重要因素. 文章对目前光伏系统中蓄电池使用的特点以及影响蓄电池使用寿命的因素进行了简要分析, 对蓄电池常用充电控制方法和策略进行了讨论. 提出了一种新的充电控制策略, 设计出了基于AVR单片机的独立光伏系统蓄电池充电管理系统. 实验表明该控制策略能在充分利用太阳能的同时提高蓄电池的荷电状态, 从而达到延长光伏系统中蓄电池使用寿命的目的.     

电网基建域移动管控系统设计

针对现有电网基建域移动管控系统技术的落后,导致系统的操作响应时间过长、丢包率过高的问题,提出电网基建域移动管控系统设计研究。系统硬件设计选取了计算机的硬件设备,软件设计主要包括项目管控模块、造价管控模块、质量管控模块、安全管控模块与技术管控模块。通过系统硬件与软件的设计实现了电网基建域移动管控系统的运行。以BP神经网络评价模型为基础进行仿真实验,结果显示设计的电网基建域移动管控系统极大地减少了操作响应时间与丢包率,充分说明设计的电网基建域移动管控系统具备更好的性能。     

Robustness and coordination in voltage control of large-scale power systems

In this paper it is shown how the robustness and the coordination of the voltage regulation actions for the transmission grid can be improved. Simpler approaches which ensure higher robustness and performances can be used if the control objectives are pursued at two hierarchical levels of different nature. Also, this is a way to coordinate means of control of different nature with a sufficient time and methodological separation in order to avoid negative mutual influence. At the first level, called the static level, optimal reachable set-points are computed for the second control level, called the dynamic level. The static level can be combined with the shunt reactive power compensation. The system non-linearities are taken into account at the static level while the dynamic level is a linear robust predictive control which takes into account the presence of asynchronous transmission delays. The predictive control strategy is based on the separation property; the output delays are handled using an original steady-state Kalman predictor of order equal to the length of the state of the system without delays. The robustness is improved at the dynamic level against uncertain delays, parametric uncertainties (like, e.g., moderate topological errors and load variations not taken into account in the control model) and unmodelled dynamics. The two-level organisation of the control allows, on one hand, to take into account the important evolutions of the system (like, e.g., large and known topological and load changes) and, on the other hand, a coherent hybrid reactive power control: the switched control of the grid shunt compensation for the reactive power is done at the static level while the reactive power injection provided by the generators is continuously handled at the dynamic level. This is a theoretical analysis of how concepts of automatic control and voltage regulation of power systems can be combined. To be applied as a control scheme, the results presented here should be adapted to a specific context (particularities of the power system and of the organisation of the power industry). They can be used, eventually in conjunction with other improvements, to existing horizontally-organised interconnections (in which all generators of a controlled region can be easily managed since owned by the same utility) or to face specific requirements of moving to the open access in the electric power industry like, e.g., tolerating simplified models in order to cover larger regions, taking into account the interaction between regions, recalibrating set-points, assisting human operator when necessary or facilitating implementation of mechanisms for the management of the reactive power based on price signals.     

Robust grid‐oriented control of high voltage DC links embedded in an AC transmission system

Several studies have shown that the way to design controllers for the high‐voltage direct current (HVDC) links impacts the transient behavior of the electric system in which the latter are inserted. This can be exploited to improve the performances of the stability of the power system. In this paper, a robust multivariable control design for the converters of an HVDC link is proposed. It is based on the coordination of the control actions of the HVDC converters and the use of a control model. The latter takes into consideration, in addition to the dynamics that mostly impact the stability of the neighbor zone of the HVDC link, several cases of faulted situations modeled as uncertainties. An H_∞ controller allowed us to achieve robustness against such uncertainties. The new controller is tested in comparison with the standard vector control and an optimal linear quadratic controller using the EUROSTAG simulation software (Tractebel Engineering, Brussels, Belgium and Réseau de Transport d'Electricité (RTE) ‐ France) on both academic and realistic large‐scale power systems. Copyright © 2015 John Wiley & Sons, Ltd.     

电流型变流器的改进模型预测控制

传统的模型预测控制(MPC)采用脉冲响应的非参数模型作为系统的预测控制模型,计算量大,很难直接应用于实时控制系统.本文提出将传统的MPC进行改进,应用到电流型变流器(CSC)功率因数校正系统中.改进的MPC根据CSC控制量与被控制量的传递函数得出CSC的一阶差分方程作为预测控制模型,同时保留传统MPC反馈校正、动态优化等优点.将此改进的MPC与传统的PID控制进行对比研究,结果表明:改进的MPC用于电流型变流器,比传统的PID控制具有更好的鲁棒性和更快速的动态响应特性.     

DC/DC开关电源模块并联供电系统均流控制研究

介绍了由两个DC/DC开关电源模块并联构成的供电系统电路结构和工作原理。该系统采用ARM芯片STM32为主控芯片产生驱动功率开关器件MOSFET的PWM脉冲[1],对供电系统的输出电压和各个模块的输出电流均实现了全数字闭环PI控制。系统输出电压稳定,能实现两个模块电流的比例分配,同时具有输出负载短路及延时恢复功能。仿真和实验结果验证了控制技术的正确性和可行性。     

Current control based power management strategy for distributed power generation system

The integration of renewable energy sources (RES) based distributed generation (DG) systems into electric grid has many challenges such as synchronization, control, power management (PM) and power quality problems. This paper proposes a references current generator (RCG) based PM strategy to control three phase inverter and manage power flow among the DG energy sources, electric grid and load demand under balanced and unbalanced grid conditions. The amplitudes of active and reactive power oscillations are also eliminated and controlled through only one flexible control parameter (FCP) under grid faults and harmonic distortions. Compared with previous similar studies, one of the important contributions is capable to inject maximum active power and minimum reactive power into electric grid and load at inverter power capacity under grid faults Another contribution is to extract the positive and negative sequence (PNS) voltage and current components with the improved fast and robust dual adaptive filters based phase locked loop (DAF-PLL). Fractional order proportional integral (FOPI) is selected as an attractive solution for AC current regulation to exhibit fast transient response and to achieve zero steady-state errors as compared with conventional current regulation controllers in synchronous or stationary frames.     

基于软总线的卫星跟踪控制系统设计与实现

卫星跟踪控制是卫星通信技术中的一项重要技术;设计了一种基于软总线机制的卫星跟踪控制系统,给出了关键的设计方案;硬件平台方面处理芯片采用FPGA+ARM的ZYNQ处理平台,保障系统中处理资源和接口扩展的需求;软件方面通过构建软总线的数据管理机制和通信代理机制,解决传统系统中耦合度高及触发条件难以精准把控等问题,使跟踪系统软件架构清晰明朗,各功能模块接口高效、便捷、易扩展;跟踪流程设计中,优化了跟踪角度调节处理时机,使跟踪算法和外设控制得以并行处理,充分利用处理资源,最终搭建测试环境验证了系统能力;结果表明,该设计有效可靠,其中软总线机制还可应用于其他外部设备复杂的环境,具有较高的应用及推广价值。