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.     

可再生能源分布式发电能量管理的复杂性研究

本文主要研究可再生能源分布式发电系统能量的优化与协调问题.基于系统能量管理中优化与协调控制问题的复杂性,提出采用基于Agent的建模与仿真方法进行研究.针对系统要求,以分散式发电系统的实体节点的映射封装Agent,提出了智能混合控制Agent的概念,建立了3层混合Agent的内部结构模型;并建立了以个体层、组织层和社会层构成的3层动态层级MAS体系结构,进一步辅以主导Agent和移动Agent辅助系统优化与决策,最终建立了一种新的面向再生能源的分散式发电系统能量管理的MAS宏观模型.最后应用有色Petri网对系统的优化与协调过程进行了动态模拟,验证了所提出的结构的正确性、合理性和有效性.     

分布式发电系统中并网逆变器的比例反馈积分控制技术

分布式发电系统并网逆变单元输出电流的控制性能直接影响到系统输出的电能质量. 传统PI控制无法消除并网电流(交流)的稳态误差, 但稳态误差存在的根本原因相关文献描述较少. 为了解释其原因, 首先建立了并网电流线性控制模型, 然后通过线性叠加定理和频域分析, 揭示了传统PI控制交流量存在稳态误差的本质, 并提出一种新的PI控制, 即比例反馈积分PFI控制. PFI控制不仅解决了传统并网电流PI控制中存在稳态误差的问题, 而且还 具有直流抑制特性. 此外, 提出的PI控制具有原理简单, 实现方便, 单相三相系统均适用等优点. 和理论分析一致, 仿真结果验证了提出的PI控制的有效性.     

An economic receding horizon optimization approach for energy management in the chlor-alkali process with hybrid renewable energy generation

This paper presents a methodology for the application of receding horizon optimization techniques to the problem of optimally managing the energy flows in the chlor-alkali process using a hybrid renewable energy system (HRES). The HRES consists of solar and wind energy generation units and fuel cells to supply energy. The HRES is also connected to the grid and allows for buying or selling electricity from and to the grid. Initially, detailed models of each system component are introduced as the basis for the simulation study. Energy management strategies are then developed to realize the objectives of meeting production requirements while minimizing the overall operating and environmental costs. Sensitivity and uncertainty analyses are carried out to elucidate the key parameters that influence the energy management strategies. Finally, production demand response is integrated into the proposed methodology.     

Predictive control of a building hybrid heating system for energy cost reduction

Today, the buildings’ energy consumption is considerable amount of whole. Therefore, optimizing energy in buildings leads to a noticeable decrease in total energy consumption of the world. Energy-efficient buildings have developed by carrying out great research effort. The control procedures serve as a privileged method to help new buildings to comply with the most optimal system as an energy consumer and thus meet ‘nearly zero-energy’.The purpose of this paper is to present a method of controlling the building temperature and simultaneously reducing the cost of providing the hybrid heating systems with sufficient energy. Investigating a room in Tehran city on a day as an example, methods of (a) Model Predictive Control (MPC) with economic optimization (MPC consecutively with On-Off), (b) MPC without economic optimization, (c) Proportional-Integral-Derivative (PID) controller optimized by Genetic Algorithm (GA) in presence of gas thermal source, (d) PID controller optimized with GA in presence of electric thermal source and (e) PID controller optimized with multi-objective GA in the presence of two gas and electric thermal sources have been designed and implemented in this research. Furthermore, the effect of each of these methods on cost reduction and temperature regulation of inside of the room has been studied. Eventually it has been specified that using MPC method with economical optimization has the highest influence on cost reduction and keeps the temperature of inside of the room in the predefined range. This method achieved cost saving of 50% compared to the MPC and GA. But the main targets of this study are both of regulating inside temperature and cost optimization. According to the main targets of this study, using MPC methods without economical optimization and multi-objective genetic algorithm would be more effective.     

基于随机模型预测控制的插电式混合动力汽车多目标能量管理策略

为了改善插电式混合动力汽车的燃油消耗和排放, 开展多目标随机模型预测控制策略的研究. 首先, 建立适用于模型预测的多元线性回归的发动机和电池模型, 建立融合燃油消耗和排放的多目标价值函数的模型预测控制, 随后, 基于随机驾驶员模型未来时刻的车速, 结合交通信息并利用动态规划(DP)算法进行参考电荷状态(SOC)优化, 进而建立多目标随机模型预测控制策略. 最后, 通过与DP, MPC等策略进行对比验证, 及给出两组不同权值进行多目标控制效果分析. 结果表明, 该策略的燃油消耗和排放最接近DP的控制效果, 且设置不同权重值可获得相应的控制目标, 说明该策略对提升燃油消耗和排放的多目标性能的有效性.     

An optimal regulation strategy with disturbance rejection for energy management of hybrid electric vehicles

The energy management problem of finding the optimal split between the different sources of energy in a charge-sustaining parallel HEV, ensuring stability and optimality with respect to a performance objective (fuel consumption minimization over a driving cycle), is addressed in this paper. The paper develops a generic stability and optimality framework within which the energy management problem is cast in the form of a nonlinear optimal regulation (with disturbance rejection) problem and a control Lyapunov function is used to design the control law. Two theorems ensuring optimality and asymptotic stability of the energy management strategy are proposed and proved. The sufficient conditions for optimality and stability are used to derive an analytical expression for the control law as a function of the battery state of charge/state of energy and system parameters. The control law is implemented in a simplified backward vehicle simulator and its performance is evaluated against the global optimal solution obtained from dynamic programming. The strategy performs within 4% of the benchmark solution while guaranteeing optimality and stability for any driving cycle.     

A reactive control strategy for networked hydrographical system management

A reactive control strategy is proposed to improve the water asset management of complex hydrographical systems. This strategy requires the definition of rules to achieve a generic resource allocation and setpoint assignment. A modelling method of the complex hydrographical network based on a weighted digraph of instrumented points is also presented. The simulation results of the strategy applied to a hydrographical system composed of one confluent and two diffluents show its efficiency and its effectiveness.     

A stochastic method for the energy management in hybrid electric vehicles

There are many approaches addressing the problem of optimal energy management in hybrid electric vehicles; however, most of them optimise the control strategy for particular driving cycles. This paper takes into account that the driving cycle is not a priori known to obtain a near-optimal solution. The proposed method is based on analysing the power demands in a given receding horizon to estimate future driving conditions and minimise the fuel consumption while cancelling the expected battery energy consumption after a defined time horizon. Simulations show that the proposed method allows charge sustainability providing near-optimal results.     

Two degree-of-freedom design for a send-on-delta sampling PI control strategy

A complete event-based two-degree-of-freedom PI controller is presented. The architecture of the control system is based on two decoupled PI controllers, one for the set-point following and one for the load disturbance rejection task. The distinctive feature of the proposed approach is that the two controllers have the same parameters and the reference tracking performance is improved by suitably modifying the reference signal applied to the set-point following controller. Examples of the technique are given. In particular, the control strategy has been applied to a distributed solar collector field.     

考虑温度舒适度与碳交易的综合能源系统优化调控

综合能源系统可以实现多能互补、能源梯级利用,但设备间复杂的耦合关系对新能源消纳与源荷波动平抑带来了极大挑战.针对此类问题,本文提出基于舒适度的温差储能与阶梯奖惩碳交易机制的调控模型.首先,在电价需求响应的基础上,构建由舒适度划分的冷热需求响应的温差储能模型.其次,建立以系统运行成本与碳排放量最低为目标的综合调控模型,在...     

Managing a hybrid energy smart grid with a renewable energy source

The aim of this work is to develop tools for optimal power flow management control in a micro grid (MG). The latter consists of a wind turbine, energy storage system, two gas turbines (GTs), and the main grid. Unlike the traditional approach, which is limited to the distribution of active power, this paper models an electrical system to coordinate and optimize the flow of both active and reactive power using discrete controls. The proposed optimal power distribution strategy has two objectives. First, it aims at forecasting over a time horizon of 24 hours the optimal distribution of the active and reactive power required for each power source connected to the MG. The proposed management incorporates the forecasts of consumption, weather, and tariffs. Second, it aims at reducing the CO₂ emissions rate by optimizing both the operating point of the two GTs and the usage of the storage unit. The proposed optimization problem for the energy management system is solved using the Bellman algorithm through dynamic programming. Its effectiveness is illustrated with various simulations carried out in the Matlab environment. The supremacy of the proposed management algorithm is highlighted by comparing its performance with conventional (restricted) management.     

电动汽车混合储能系统拓扑结构与控制策略综述

混合储能系统兼具高功率密度和高能量密度,可有效提升电动汽车动力性能和续驶里程.围绕电动汽车混合储能系统拓扑结构和控制策略,本文首先对混合储能系统及其典型储能装置进行概述,并对混合储能系统技术难点进行分析.之后在分析隔离型双向DC/DC变换器和非隔离型双向DC/DC变换器拓扑结构、工作原理和基本特性的基础上,综述分析了被动、半主动和全主动3种混合储能系统的工作原理和优缺点.然后,重点分析了基于规则的控制策略、基于优化的控制策略和混合控制策略3大类混合储能系统控制策略的工作原理.最后对混合储能系统的发展趋势进行了展望.     

Intrinsic dynamics and total energy-shaping control of the ballbot system

Research on bipedal locomotion has shown that a dynamic walking gait is energetically more efficient than a statically stable one. Analogously, even though statically stable multi-wheeled robots are easier to control, they are energetically less efficient and have low accelerations to avoid tipping over. In contrast, the ballbot is an underactuated, nonholonomically constrained mobile robot, whose upward equilibrium point has to be stabilised by active control. In this work, we derive coordinate-invariant, reduced, Euler–Poincaré equations of motion for the ballbot. By means of partial feedback linearisation, we obtain two independent passive outputs with corresponding storage functions and utilise these to come up with energy-shaping control laws which move the system along the trajectories of a new Lagrangian system whose desired equilibrium point is asymptotically stable by construction. The basin of attraction of this controller is shown to be almost global under certain conditions on the design of the mechanism which are reflected directly in the mass matrix of the unforced equations of motion.     

Stability and switching control design issues for a class of discrete time hybrid systems

For the class of systems considered, necessary and sufficient stabilizability conditions are unknown. However, by considering the same systems with unknown but bounded exogenous disturbances, we give finitely computable conditions, sufficient for stabilizability without disturbances, yet necessary for stabilizability with disturbances.     

空分系统节能优化控制策略设计

针对空分系统运行控制中存在的问题,提出了基于自动变负荷技术与多模型自适应两种优化控制策略,以实现系统最大限度的节能降耗。通过实际的数据分析表明,上述两种控制方案具有可行性,系统存在问题得以解决,节能运行效果良好。     

无线网络化系统自适应能量调度与协同控制

无线网络化系统（wireless networked control system,WNCS）中节点能量受限是影响系统性能的重要因素．本文提出了一种自适应能量调度方法解决节点能量与控制需求问的矛盾,在采样周期与能量消耗之间关系的基础上,利用动态采样周期实现能耗的实时调节,满足节点生存时间的需求．进而,将自适应采样的WNCS建模为一类具有短暂不确定切换信号的离散切换系统,采用切换状态反馈控制律,利用切换系统理论分析了系统的稳定性,给出了系统渐近稳定时控制器增益与滞留时间需要满足的约束条件．最后在Truetimel．5和MATLAB仿真平台上验证了文中提出的方法和结论．     

掩模管理的综合自动化控制系统的软件设计

介绍了基于欧姆龙CS1GH-CPU45H可编程逻辑控制器的掩模管理综合自动化控制系统的软件设计.该软件采用模块化设计方法和任务调用机制,简化了程序设计的过程,缩短了程序的扫描周期,提高了程序的运行效率.为了便于上位机监控设备运行状态,对执行机构的每个动作和过程进行了状态编码,程序将按照运行进程将状态编码、各个轴的当前位置和故障信息写到约定的数据区域中去.实验验证了该软件设计方法的可靠性和可行性.     

A model-based supervisory energy management strategy for a 12 V vehicle electrical system

This paper describes the development, implementation, and experimental verification of a supervisory energy management strategy for the vehicle electrical system of a passenger car. The control strategy commands the alternator duty cycle such that vehicle fuel economy is optimized whilst the instantaneous load current demand is met and constraints on the system voltage and battery state of charge are satisfied.The work is based on a control-oriented model of the vehicle electrical system, experimentally validated against vehicle data. Then, a constrained global optimal control problem is formulated for the energy management of the electrical system, and analytically solved using the Pontryagin׳s Minimum Principle (PMP). The optimal solution obtained is evaluated for a range of different driving cycles and electrical load current profiles, leading to the formulation of an adaptive supervisory control strategy that is implemented and tested in vehicle.     

Integral sliding mode control for Euler‐Lagrange systems with input saturation

This paper investigates the robust control for the Euler‐Lagrange (EL) system with input saturation by using the integral sliding mode control and adaptive control. An integral sliding mode surface that is suitable for solving the problem of the input constraint is given based on the saturation function. By using the integral sliding mode surface, two robust antisaturation controllers are designed for the EL system with external disturbances. The first controller can deal with the external disturbances with known bounds, whereas the second one can compensate the external disturbances with unknown bounds by using the adaptive control. Finally, the effectiveness of the proposed controllers is demonstrated by strict theoretical analysis and numerical simulations.