Enhanced Perturb and Observe Control Algorithm for a Standalone Domestic Renewable Energy System

The generation of electricity,considering environmental and eco-nomic factors is one of the most important challenges of recent years.In this article,a thermoelectric generator(TEG)is proposed to use the thermal energy of an electric water heater(EWH)to generate electricity independently.To improve the energy conversion efficiency of the TEG,a fuzzy logic con-troller(FLC)-based perturb&observe(P&O)type maximum power point tracking(MPPT)control algorithm is used in this study.An EWH is one of the major electricity consuming household appliances which causes a higher electricity price for consumers.Also,a significant amount of thermal energy generated by EWH is wasted every day,especially during the winter season.In recent years,TEGs have been widely developed to convert surplus or unused thermal energy into usable electricity.In this context,the proposed model is designed to use the thermal energy stored in the EWH to generate electricity.In addition,the generated electricity can be easily stored in a battery storage system to supply electricity to various household appliances with low-power-consumption.The proposed MPPT control algorithm helps the system to quickly reach the optimal point corresponding to the maximum power output and maintains the system operating point at the maximum power output level.To validate the usefulness of the proposed scheme,a study model was developed in the MATLAB Simulink environment and its performance was investigated by simulation under steady state and transient conditions.The results of the study confirmed that the system is capable of generating adequate power from the available thermal energy of EWH.It was also found that the output power and efficiency of the system can be improved by maintaining a higher temperature difference at the input terminals of the TEG.Moreover,the real-time temperature data of Abha city in Saudi Arabia is considered to analyze the feasibility of the proposed system for practical implementation.

Voltage Control of a 12/8 Pole Switched Reluctance Generator Using Fuzzy Logic

This paper presents a voltage controller for a 12/8 switched reluctance generator (SRG). SR machines have a robust with simple structure because they have no windings or permanent magnets on the rotor, so they are capable of working at high speed application and at rough condition. However, due to nonlinear nature, doubly salient poles, time variant parameters, and non-ideal current waveform, The SRG output voltage inherently contains ripples. The proposed voltage controller is based on fuzzy logic that is very efficient over uncertainty and parameter variations. The effectiveness of the proposed control method is verified by comparing the obtained result with that of a PI-controller.

A Fuzzy Logical MPPT Control Strategy for PMSG Wind Generation Systems

Making full use of wind power is one of the main purposes of the wind turbine generator control. Conventional hill climbing search （HCS） method can realize the maximum power point tracking （MPPT）. However, the step size of HCS method is constant so that it cannot consider both steady-state response and dynamic response. A fuzzy logical control （FLC） algorithm is proposed to solve this problem in this paper, which can track the maximum power point （MPP） quickly and smoothly. To evaluate MPPT algorithms, four performance indices are also proposed in this paper. They are the energy captured by wind turbine, the maximum power-point tracking time when wind speed changes slowly, the fluctuation magnitude of real power during steady state, and the energy captured by wind turbine when wind speed changes fast. Three cases are designed and simulated in MATLAB/Simulink respectively. The comparison of the three MPPT strategies concludes that the proposed fuzzy logical control algorithm is more superior to the conventional HCS algorithms.

Adaptive Fuzzy Sliding Mode Controller for Grid Interface Ocean Wave Energy Conversion

This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generator (SEIG). The aim of the developed control method is to automatically tune and optimize the scaling factors and the membership functions of the Fuzzy Logic Controllers (FLC) using Multi-Objective Genetic Algorithms (MOGA) and Multi-Objective Particle Swarm Optimization (MOPSO). Two Pulse Width Modulated voltage source PWM converters with a carrier-based Sinusoidal PWM modulation for both Generator- and Grid-side converters have been connected back to back between the generator terminals and utility grid via common DC link. The indirect vector control scheme is implemented to maintain balance between generated power and power supplied to the grid and maintain the terminal voltage of the generator and the DC bus voltage constant for variable rotor speed and load. Simulation study has been carried out using the MATLAB/Simulink environment to verify the robustness of the power electronics converters and the effectiveness of proposed control method under steady state and transient conditions and also machine parameters mismatches. The proposed control scheme has improved the voltage regulation and the transient performance of the wave energy scheme over a wide range of operating conditions.

Performance analysis of CDMA power control system based on fuzzy prediction

Power control is of paramount importance in combating the near-far problem and co-channel interference in a CDMA cellular system. Due to fast fading and ambient interference in a wireless channel, conventional fixed-step power control schemes have difficulty in compensating for the fast fading channel dynamically and in a timely manner. To acquire flexible power regulation in order to maintain required transmission capacity under the given transmission quality requirement, we propose a hybrid power control scheme which makes full use of the simple fuzzy inference rule refined by an operator in the fuzzy control and prediction property from related previous results in Generalized Prediction Control (GPC). In implementation of this strategy, we classify the fading zone into three levels according to the signal-to-noise-rate (SNR) requirement. In each level the power compensation amount varies with fading gradient and the compensation scheme varies as well. The digital results show that adoption of the fuzzy-GPC power regulation scheme has acquired a reasonable performance improvement when compared with fixed-step and fuzzy schemes. According to theoretic analysis and simulation results, we can conclude that under a variational transmission environment, a flexible power regulation scheme such as fuzzy-GPC is easy to adapt to the environment and thus overcomes the near-far effect and multi-access interference effectively.

Advanced in power control for distributed generation system using cooperative algorithms

To develop efficient power control strategies for a distributed generation system in order to improve the overall system efficiency,we propose a cooperative algorithm to analyze and design the controller,in which elements of conventional mathematical optimization algorithms are combined with adaptive dynamic elements drawn from intelligent control theory.In our design,the sequential quadratic programming algorithm was first utilized to obtain an optimal solution for power distribution among multiple units.Fuzzy system was then developed to implement the optimal strategies on the basis of optimal solution.In addition,parameters of the fuzzy system were adapted via a genetic algorithm.The simulation results illustrate that the methodology described is useful for a range of control system designs.

PLC辅助下船舶柴油发电机转速控制研究

柴油发电机在运行过程中受到外部扰动时转速的波动幅度增大,影响发电机的输出稳定性和效率,因此,本文提出一种PLC(可编程逻辑控制器)辅助下船舶柴油发电机转速控制方法。根据柴油发电机的基本工作结构,对其各个部件的模型进行构建与分析。通过分析各部件模型得出的参数和特性,从静态与动态2个角度出发,选取船舶柴油发电机转速控制指标,包括静差率、超调量和动态降落。将上述指标与PLC程序逻辑结合,通过监测实时数据来判断当前状态,然后根据反馈信息调节控制参数,有效地控制柴油发电机的转速。实验结果表明,本文方法能够更加快速地调整柴油发电机的转速,并且受到外力扰动时能够迅速调整回归平稳运行状态,保证柴油发电机的长期平稳运转。

基于模糊逻辑的空调系统广义预测控制参数整定

针对多输入多输出(multiple-input-multiple-output,MIMO)变风量空调系统(variable air volume,VAV),本文提出了一种基于模糊逻辑和事件触发的广义预测控制(generalized predictive control,GPC)参数整定方法。针对多变量VAV空调系统,基于输出斜率等新型模糊目标参数及高斯双边形隶属度函数建立模糊预测模型,提高了隶属函数拟合度以更贴切地反映系统当前时刻状态。利用麻雀智能算法(sparrow search algorithm,SSA)构建隶属度函数,对GPC控制器中的柔化因子和加权系数进行在线分段整定,有效提升了系统性能。此外,在参数整定过程中,引入事件触发机制(event-triggered mechanism,ETM),在保证控制性能的同时,避免了不必要的控制器采样与更新,降低了系统在线计算量并减少了能源消耗。最后通过VAV空调系统仿真实验验证,证明了本文提出方法的可行性和有效性。

A Novel Modified Fuzzy-predictive Control of Permanent Magnet Synchronous Generator Based Wind Energy Conversion System

A wind energy conversion system(WECS)based on a permanent magnet synchronous generator(PMSG)is an effective solution for renewable energy generation in modern power systems.The main advantages of PMSG include high performance at high and low speeds,minimal control effort owing to lower rotor inertia,self-excitation,high reliability,and simplicity of structure compared with induction generators.However,the intermittent nature of wind energy implies that maximum efficiency is not obtained from this system.Accordingly,maximum power point tracking(MPPT)in wind turbine systems has been proposed to address this problem.Traditional MPPT strategies suffer from severe output power fluctuations,low efficiency,and significant ripples in turbine rotation speed.This paper presents a novel MPPT control strategy based on fuzzy logic control(FLC)and model predictive control(MPC)to extract the maximum power from a PMSG-WECS and control the machine-side and grid-side converters.The simulation results obtained from Matlab/Simulink confirm the superiority of the control model in eliminating the output power fluctuations of the wind generators and accurately tracking the maximum power point.A comparative study between conventional MPPT and control methods is also conducted.

某机场航站楼低压供配电系统的共性和差异分析

文章介绍了某机场T3、T4航站楼、助航灯光站3个在民航系统中重要程度最高的低压配电系统,着重分析了其共性和差异,使得在设计前就可了解低压配电系统,并根据配电系统的重要程度、可靠性要求、资金预算确定配电方案及元器件档次,确保配电设备可靠性高、易于维护、故障率低。

基于PLC风光互补发电系统效率提升装置的设计与实现

在可再生能源利用需求迅速增长的背景下,风光互补发电系统作为一种绿色、可持续的能源解决方案得到了广泛应用。其中,如何提高系统的效率是该领域的研究关键。文章基于可编程逻辑控制器(Programmable Logic Controller,PLC),针对风光互补发电系统,设计并实现了一种效率提升装置。通过优化控制策略、提升系统整体性能,实现提高能源利用效率,推动风光互补发电系统在可再生能源领域的发展与应用。

Application of fuzzy logic control algorithm as stator power controller of a grid-connected doubly-fed induction generator

This paper discusses the power outputs control of a grid-connected doubly-fed induction generator （DFIG） for a wind power generation systems. The DFIG structure control has a six diode rectifier and a PWM IGBT converter in order to control the power outputs of the DFIG driven by wind turbine. So, to supply commercially the electrical power to the grid without any problems related to power quality, the active and reactive powers （Ps, Qs） at the stator side of the DFIG are strictly controlled at a required level, which, in this paper, is realized with an optimized fuzzy logic controller based on the grid flux oriented control, which gives an optimal operation of the DFIG in sub-synchronous region, and the control of the stator power flow with the possibility of keeping stator power factor at a unity.

Impact of wind power generating system integration on frequency stabilization in multi-area power system with fuzzy logic controller in deregulated environment

Among the available options for renewable energy integration in existing power system, wind power is being considered as one of the suited options for future electrical power generation. The major constraint of wind power generating system （WPGS） is that it does not provide inertial support because of power electronic converters between the grid and the WPGS to facilitate frequency stabilization. The proposed control strategy suggests a substantial contribution to system inertia in terms of short-term active power support in a two area restructured power system. The control scheme uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, which balances the drop in frequency and tie-line power during transient conditions. This paper presents a comprehensive study of the wind power impact with increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for the same power system model with the proposed control scheme. Simula- tion results advocates the justification of control scheme over other schemes.

Doubly-fed induction generator drive based WECS using fuzzy logic controller

The purpose of this paper is to improve the control performance of the variable speed, constant frequency doubly-fed induction generator in the wind turbine generation system by using fuzzy logic controllers. The control of the rotor-side converter is realized by stator flux oriented control, whereas the control of the grid-side converter is performed by a control strategy based on grid voltage orientation to maintain the DC-link voltage stability. An intelligent fuzzy inference system is proposed as an alternative of the conventional proportional and integral （PI） controller to overcome any disturbance, such as fast wind speed variation, short grid voltage fault, parameter variations and so on. Five fuzzy logic controllers are used in the rotor side converter （RSC） for maximum power point tracking （MPPT） algorithm, active and reactive power control loops, and another two fuzzy logic controllers for direct and quadratic rotor currents components control loops. The performances have been tested on 1.5 MW doubly-fed induction generator （DFIG） in a Matlab/Simulink software environment.

Torque Distribution Strategy for Integrated Starter/ Generator Hybrid Bus Implemented by Fuzzy Algorithm

A torque distribution strategy was designed by using fuzzy logic to realize the optimal control. The vehicle load zones were dynamically divided into several zones by several torque lines to indicate the drivers demand and the high or low efficient operating areas of the diesel engine. The fuzzy logic controller with trapezoid membership function and Mamdani rule reference mechanism was utilized. There are over 100 rules used in this fuzzy-based torque distribution strategy which are sorted into four rule-bases. The fuel economy and acceleration tests were designed to test and validate the integrated starter/generator (ISG) bus perfor-mance using fuzzy-based torque distribution strategy. The fuel economy is improved 7.7% compared with the rule-based strategy. Finally the road test results reveal that there is about 15% improvement of fuel economy. And the 0-50 km/h acceleration time is 9.5% shorter than the original bus.

Stabilization of Wind Farm by Using PMSG Based Wind Generator Taking Grid Codes into Consideration

This paper presents a new operational strategy for a large-scale wind farm (WF) which is composed of both fixed speed wind turbines with squirrel cage induction generators (FSWT-SCIGs) and variable speed wind turbines with permanent magnet synchronous generators (VSWT-PMSGs). FSWT-SCIGs suffer greatly from meeting the requirements of fault ride through (FRT), because they are largely dependent on reactive power. Integration of flexible ac transmission system (FACTS) devices is a solution to overcome that problem, though it definitely increases the overall cost. Therefore, in this paper, a new method is proposed to stabilize FSWT-SCIGs by using VSWT-PMSGs in a WF. This is achieved by injecting the reactive power to the grid during fault condition by controlling the grid side converter (GSC) of PMSG. The conventional proportional-integral (PI)-based cascaded controller is usually used for GSC which can inject small amount of reactive power during fault period. Thus, it cannot stabilize larger rating of SCIG. In this paper, a suitable fuzzy logic controller (FLC) is proposed in the cascaded controller of GSC of PMSG in order to increase reactive power injection and thus improve the FRT capability of WF during voltage dip situation due to severe network fault. To evaluate the proposed controller performance, simulation analyses are performed on a modified IEEE nine-bus system. Simulation results clearly show that the proposed method can be a cost-effective solution which can effectively stabilize the larger rating of SCIG compared to conventional PI based control strategy.

控制型教养方式:历史演进、生成逻辑与破解路径

控制型教养式是以父母需要为中心、以监控或专制的方式进行的父母教养方式。它具体分为行为控制和心理控制两种形式,频繁和过强的心理控制会严重影响子女的心理健康和发展。中国的控制型教养经历了封建社会时期“全方位”的行为和心理控制阶段,发展至今呈现出以“学业倾注”为特征的高投入高控制行为,它是一种极具中国特色的社会化教养方式,其背后的生成逻辑是传统孝道的文化基因、集体权威的生长土壤以及“反哺”交换的利益诉求三重影响下的结果,而破解控制型教养方式的关键在于提供社会安全感和加强儿童平权思想文化的引领。

“十六字”治水方针与南水北调中线受水区后续高质量发展研究

南水北调中线工程进入后续发展阶段,如何充分发挥水资源对受水区高质量发展的作用尤为重要。“节水优先、空间均衡、系统治理、两手发力”的“十六字”治水方针是针对现实水资源、水生态和水环境状况等新型水问题的科学治水思想,是新时代水生态建设的指导思想。就生成逻辑而言,马克思主义治水观和中国传统治水文化是它坚实的理论基础;历经中国革命、建设和改革的历史实践的严酷考验;习近平总书记的创新凝练更增强其针对性和指导性。在南水北调中线受水区高质量发展中,“十六字”治水方针能够有效提高水资源的利用、配置、治理和运营能力,充分发挥水资源对受水区高质量发展的基础支撑作用。

教师负担技术治理的伦理风险及其防控

现代技术的发展和使用为教师负担的治理提供了新的视角和手段,但同时也带来了相应的伦理风险,导致教师负担技术治理的异化。为此,文章首先阐述了教师负担技术治理的伦理风险表征,包括教师负担问题失真、人机关系主从倒置、教师隐私受到侵害、教师诉求逐渐消解。然后,文章从技术实践的特性出发,分析了这种风险产生的逻辑在于量化表征的数字化逻辑、算法执行的控制性逻辑、技术平台的开放性逻辑以及技术运行的自主性逻辑。最后,文章从关注教师感知、引导技术服务、维护数据正义、回归治理初衷四个方面,提出了教师负担技术治理的防控路径。文章通过对教师负担技术治理伦理风险的审视和溯源,期望为技术手段更好地推动教师负担治理提供参考。

智能思政伦理风险的生成逻辑、表现形式及防控机制

智能思政是人工智能与思想政治教育融合发展的新兴事物,智能技术在为思想政治教育创设新场景、提供新手段的同时,其可能引发的伦理风险也需要引起人们的重视。智能思政伦理风险的生成是内生性逻辑、功能性逻辑和应用性逻辑共同作用的结果,主要表现在伦理关系失衡、伦理价值失序、伦理行为失当和伦理规范失控等方面。为确保智能思政健康发展,需要从价值引领机制、协同治理机制、法规约束机制、素养培育机制和监测评估机制等维度出发,做好智能思政伦理风险的整体性防控。