Control System Design for Low PowerMagnetic Bearings in a Flywheel Energy Storage System

This paper presents a theoretical and experimental study on controller design for the AMBs in a small-scale flywheel energy storage system,where the main goals are to achieve low energy consumption and improved rotordynamic stability.A H-infinity optimal control synthesis procedure is defined for the permanent-magnet-biased AMB-rotor system with 4 degrees of freedom.Through the choice of design weighting functions,notch filter characteristics are incorporated within the controller to reduce AMB current components caused by rotor vibration at the synchronous frequency and higher harmonics.Experimental tests are used to validate the controller design methodology and provide comparative results on performance and efficiency.The results show that the H-infinity controller is able to achieve stable rotor levitation and reduce AMB power consumption by more than 40%(from 4.80 to 2.64 Watts)compared with the conventional PD control method.Additionally,the H-infinity controller can prevent vibrational instability of the rotor nutation mode,which is prone to occur when operating with high rotational speeds.

Integrated Power and Single Axis Attitude Control System with Two Flywheels

The existing research of the integrated power and attitude control system（IPACS） in satellites mainly focuses on the IPACS concept,which aims at solving the coupled problem between the attitude control and power tracking.In the IPACS,the configuration design of IPACS is usually not considered,and the coupled problem between two flywheels during the attitude control and energy storage has not been resolved.In this paper,an integrated power and single axis attitude control system using two counter rotating magnetically suspended flywheels mounted to an air table is designed.The control method of power and attitude control using flywheel is investigated and the coupling problem between energy storage and attitude control is resolved.A computer simulation of an integrated power and single axis attitude control system with two flywheels is performed,which consists of two counter rotating magnetically suspended flywheels mounted to an air rotary table.Both DC bus and a single axis attitude are the regulation goals.An attitude ＆ DC bus coordinator is put forward to separate DC bus regulation and attitude control problems.The simulation results of DC bus regulation and attitude control are presented respectively with a DC bus regulator and a simple PD attitude controller.The simulation results demonstrate that it is possible to integrate power and attitude control simultaneously for satellite using flywheels.The proposed research provides theory basis for design of the IPACS.

Design of an adaptive finite-time controller for synchronization of two identical/different non-autonomous chaotic flywheel governor systems

The centrifugal flywheel governor （CFG） is a mechanical device that automatically controls the speed of an engine and avoids the damage caused by sudden change of load torque. It has been shown that this system exhibits very rich and complex dynamics such as chaos. This paper investigates the problem of robust finite-time synchronization of non-autonomous chaotic CFGs. The effects of unknown parameters, model uncertainties and external disturbances are fully taken into account. First, it is assumed that the parameters of both master and slave CFGs have the same value and a suitable adaptive finite-time controller is designed. Second, two CFGs are synchronized with the parameters of different values via a robust adaptive finite-time control approach. Finally, some numerical simulations are used to demonstrate the effectiveness and robustness of the proposed finite-time controllers.

Application of the Latching Control System on the Power Performance of a Wave Energy Converter Characterized by Gearbox,Flywheel,and Electrical GeneratorGustavor

The latching control represents an attractive alternative to increase the power absorption of wave energy converters(WECs)by tuning the phase of oscillator velocity to the wave excitation phase.However,increasing the amplitude of motion of the floating body is not the only challenge to obtain a good performance of the WEC.It also depends on the efficiency of the power take-off system(PTO).This study aims to address the actual power performance and operation of a heaving point absorber with a direct mechanical drive PTO system controlled by latching.The PTO characteristics,such as the gear ratio,the flywheel inertia,and the electric generator,are analyzed in the WEC performance.Three cylindrical point absorbers are also considered in the present study.A wave-to-wire model is developed to simulate the coupled hydro-electro-mechanical system in regular waves.The wave energy converter(WEC)performance is analyzed using the potential linear theory but considering the viscous damping effect according to the Morison equation to avoid the overestimated responses of the linear theory near resonance when the latching control system is applied.The latching control system increases the mean power.However,the increase is not significant if the parameters that characterize the WEC provide a considerable mean power.The performance of the proposed mechanical power take-off depends on the gear ratio and flywheel.However,the gear ratio shows a more significant influence than the flywheel inertia.The operating range of the generator and the diameter/draft ratio of the buoy also influence the PTO performance.

Earth-observation satellite attitude control using passive and active hybrid magnetically suspended flywheels

The control strategy is presented using passive and active hybrid magnetically suspended flywheels（P＆A MSFWs）,which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P＆A MSFW has more rotation degrees of freedom（DOFs）since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law（SMC）to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law.

一种适应卫星姿态侧摆机动的混合轮系控制方法

针对高稳定度轮控大型卫星因动量轮力矩小而难以满足侧摆成像任务需求问题,开展了混合轮系配置方案及控制方法研究。首先,提出常规轮系配置卫星滚动轴方向串联大力矩飞轮的混合配置方案,并设计飞轮开环前馈与常规动量轮闭环反馈相结合的控制策略;其次,设计以容许角动量最大量为权重的飞轮组前馈力矩分配律和具有角动量反馈的飞轮力矩跟踪控制方法,实现飞轮力矩合理分配及其模型不确定性导致输出力矩偏差抑制;然后,设计估计器对星体内外扰动力矩进行估计与补偿,以确保卫星高稳定度性能实现;最后,给出在轨应用情况,验证所提出方案及方法的有效性。在轨应用表明,采用该控制方法,有效缩短了整星侧摆稳定时间达100 s以上,且非机动期间姿态稳定度优于3.75×10-5(°)/s。

飞轮储能系统的计算机处理技术研究

目前能源消费与能源发展下的环保问题是我国能源研究的核心,飞轮储能功率较高且操作技术相对直接不会造成环境污染,是一种较为先进的储能技术。本文综述了飞轮储能系统的核心结构,包括飞轮转子结构以及飞轮轴承结构;同时历数了当前较为先进的针对飞轮储能电机控制的计算机处理控制技术,以期为后续研究提供一定思路。

磁力轴承——过去、现在和未来

磁力轴承是集电磁学、转子动力学、传感技术、控制工程等学科知识为一体的典型机电一体化产品,在高速、洁净、低功耗、低振动等应用场景具有机械轴承无法比拟的优势,但同样存在诸多技术难点。基于磁力轴承的发展历程,重点对磁力轴承的类型、工作原理、控制算法、控制硬件进行了综述和分析;介绍了磁力轴承功率放大器技术、控制技术、监测技术,以及设计、制造、系统集成等方面的关键技术;对磁力轴承目前在高速电动机、透平机械、人工心脏、储能飞轮、磁悬浮推进器、磁悬浮高速电主轴等方面的应用情况进行了梳理;提出了磁力轴承承载力、精度及可靠性、跌落保护、环境适应性、标准化、成本等面临的问题,并预测了磁力轴承的未来发展趋势。

飞轮储能辅助火电机组一次调频及其性能评价

为促进太阳能、风能等新能源消纳,进一步拓宽火电储能技术升级和灵活性改造渠道,助力双碳目标和新型电力系统建设,提出增设储能系统辅助火电机组调频以解决火电机组爬坡慢、机组振荡不稳定等问题。基于国内外研究现状,提出机组以及储能系统荷电状态出力控制策略模型,通过Matlab/Simulink搭建两区域电网进行模拟仿真。结果表明,在阶跃扰动下区域1机组耦合1 MW飞轮储能系统后,峰值降至1.93×10^(-3)pu,降低4×10^(-4) pu,占原频率波动率的9.39%,机组实际出力从2.45×10^(-2)pu降至1.61×10^(-2)pu,降低34%。结果表明,在外界相同扰动条件下,采用飞轮储能辅助火电机组调频可有效减小系统频率波动量,减少汽轮机输出功率波动,提升调频性能。

基于逐次变分模态分解的飞轮-火电一次调频控制策略

随着新型电力系统的大力建设与推广,火电机组面临的调频压力增大,提出一种逐次变分模态分解的飞轮-火电一次调频控制策略。首先,以飞轮储能和火电机组为研究对象,建立考虑新能源占比的飞轮-火电一次调频模型;其次,将一次调频功率指令利用逐次变分模态方法分解,由火电机组响应分解后的低频功率指令,同时设计飞轮储能下垂优化控制方法,实现飞轮储能与火电机组响应频率变化的协同控制;最后在不同工况下仿真验证,结果表明所提策略可有效避免火电机组一次调频时的频繁出力,减小火电机组响应频率变化时的调控要求,同时可最大限度地利用飞轮储能调频容量并保证飞轮储能调频期间的运行安全,进一步提升了系统的频率响应能力。

飞轮储能技术在断路器动态特性检测中的应用

在地铁列车断路器动态特性检测中,引入飞轮储能系统能够有效回收列车再生制动能量,稳定断路器开关动作电压,但单飞轮储能系统容量较小,难以满足列车再生制动能量利用需求,飞轮储能阵列(FESA)是解决这一问题的有效手段.首先,分析飞轮储能系统的数学模型和运行特性;然后,考虑稳压节能及弱磁需求,给出基于多电压阈值的单飞轮储能系统控制策略,并在此基础上针对飞轮阵列均速控制和工作模式管理等核心问题,提出基于转差修正控制和基于“电压-转速-电流”三闭环控制的两种飞轮储能阵列控制策略;最后,通过仿真和实验验证飞轮储能阵列控制策略的可行性.

复杂工况下储能飞轮转子传力支承与减振设计

针对复杂工况下飞轮转子上、下传力支承角接触球轴承与支座间隙配合导致的振动问题,以及真空环境下振动控制问题,提出飞轮转子上支承采用圆柱滚子轴承,下支承采用深沟球轴承+成对角接触球轴承联合传力支承方案,解决了复杂工况下轴向力调整、磁轴承失效、轴向力平衡、支承刚度连续、支承系统变形协调等结构设计难题。同时引入一种主控式弹支干摩擦阻尼器(ESDFD),抑制转子径向振动。采用有限元法建立ESDFD-储能飞轮转子系统耦合动力学模型,计算飞轮转子动力学特性,分析单/双阻尼器对转子振动的控制效果。结果表明:针对转子一阶、二阶模态振动,采用单/双阻尼器控制方式,最大响应均低于30μm,减振比超过90%。

基于模糊卡尔曼滤波和改进滑模控制的风电场飞轮储能控制策略

在风电场并网点处配置一定容量的飞轮储能装置(FESS)可以有效平滑并网功率,提高风电场的电网友好性。为提高FESS的功率响应速度,增强对风电功率波动的平抑效果,同时避免在功率波动太大时储能过充/过放,文章提出了一种基于模糊卡尔曼滤波和改进滑模控制(SMC)的飞轮储能控制策略。根据FESS的实时转速和功率自适应调节卡尔曼增益,将滤波结果与风电场实际输出功率的差值作为滑模控制器的输入,实现对飞轮储能的功率控制。仿真结果表明,文章提出的控制策略具有较好的动态响应特性,可以有效平滑风电功率,使其满足并网要求,在平滑过程中保证飞轮转速在限定范围内,有利于延长FESS的使用寿命。

飞轮储能阵列系统协调控制方法综述

因受材料、成本和技术等因素制约,提高单个飞轮储能装置的容量较为困难,难以满足长时间大功率的需求。对此提出使用飞轮阵列来提高飞轮系统的总储能容量,进而降低装置的研发和生产成本。对于飞轮阵列储能系统,研究各储能单元协调控制、相互配合的控制策略是实现阵列高效、安全运行的解决方案。从飞轮储能阵列系统拓扑结构、协调控制策略及协调控制算法进行全面的综述。从飞轮储能阵列不同并网拓扑结构出发,探讨了适用于直流母线并联和交流母线并联对应的功率分配控制策略;随后以飞轮储能阵列并行接入电网为切入点,分别对集中式、主从式与分布式协调控制算法进行比较研究和归纳总结,重点评述了分布式一致性算法优势,并在此基础上进一步总结基于智能算法高效率求解的功率分配控制策略。最后,指出了飞轮储能阵列系统并网运行协调控制面临的挑战。

基于矩阵变换器的飞轮储能模型预测控制策略

飞轮储能系统常用的背靠背变换器中间存在直流环节及电解电容,使得变换器体积庞大,而且直流环节电解电容器会带来直流电压控制、寿命和维护成本等问题。针对上述问题,采用矩阵变换器作为飞轮储能系统的控制变换器,有效地融入了矩阵变换器的优势,避免了背靠背变流器中直流环节及电解电容带来的问题。在分析储能系统工作原理的基础上,考虑到矩阵变换器电压传输比的限制,通过理论计算得出基于矩阵变换器的飞轮储能系统的运行范围。通过理论分析得到了飞轮储能系统功率与飞轮转速的关系,然后利用转速外环电流内环的双闭环控制方式实现对飞轮储能系统的控制。电流内环采用模型预测控制策略对矩阵变换器进行控制,从而实现飞轮储能系统的充放电控制。Matlab/Simulink中的仿真结果验证了运行范围分析的准确性和所提控制策略的有效性.

考虑火电运行平稳性的飞轮储能辅助二次调频控制策略

为解决电网波动剧烈导致的火电机组运行平稳性问题,提出一种考虑火电运行平稳性的飞轮储能辅助二次调频控制策略。首先,建立了超超临界火电机组联合飞轮储能的二次调频控制模型;其次,提出了一种基于多层变增益速率限制的AGC指令非线性分解方法;最后,综合机组平稳性和系统AGC性能设计了适应度函数,借助鲸鱼优化算法(WOA)实现了最优化的速率限制算法参数获取。基于上述方法设计了火储协同二次调频控制策略。以某1000 MW火电机组-飞轮储能联合系统为例进行了仿真验证。结果表明:所提控制策略在不影响系统调频性能的前提下可以使联合系统有效响应系统高频指令,减小了火电机组的动作幅度,提升了机组运行的平稳性。

姿控飞轮轴承供油器设计与精准供油分析

姿控飞轮转子系统是飞行器飞行姿态的重要控制部件,对轴承精准润滑与供油可靠性提出了严格要求。基于固体间隙密封的反向设计原理,本文设计了一种依靠离心力自动调节轴承供油率的微型供油器,充分利用两个轴承之间的狭小空间,结构简单且可靠性高。首先建立了供油速率的流固耦合理论分析模型,得到了供油速率的半解析解,研究了供油器过盈接触面的几何参数等对供油速率的影响规律,发现供油器的供油速率与供油量可以通过优化过盈配合界面的几何尺寸、表面粗糙度和过盈配合压力等来实现精确控制,供油速率与过盈接触界面名义间隙的立方和周向长度成正比,与润滑油粘度和接触面轴向宽度成反比。供油率与轴承转速的平方成正比,使得轴承在高速运转时可以自动得到足够的润滑油。此技术可以应用于航天航空器的精密姿控飞轮系统以及其他各类精密轴承转子系统的供油设计。

计及灵活经济环保运行的火电-飞轮储能系统容量配置与调频参数协同优化

提出了一种计及灵活经济环保运行的火储系统容量配置与调频参数协同优化方法。首先,设计了一种基于低通滤波自动分配火储功率和考虑储能荷电状态自恢复的火储联合一次调频协调控制策略;综合考虑系统调频性能、投入运行成本、污染物排放等,建立了火储容量配置与调频参数协同优化模型,并给出了基于粒子群算法的求解方法。最后,以某火储系统为例进行仿真验证。结果表明:协调控制策略和协同优化方法具有有效性。

飞轮储能装置在轨道交通中的应用研究

城市轨道交通中列车频繁启动制动,制动能量大,网压波动大,有些线路存在钢轨电位严重的问题。飞轮储能装置具有功率大、响应速度快、寿命长等特点,可以对再生制动能量在直流侧进行即收即用,节能效果好,能稳定网压波动。由于飞轮储能装置的接入可以实现多点回流、缩短电流回流路径,故对钢轨电位也有改善效果。文章分别就既有线路和新建线路,考虑牵引所空间限制、储能装置平均功率峰值、节能效果等因素,说明了飞轮储能装置的容量配置方法并针对实际案例进行容量配置说明。为使飞轮储能装置的控制策略灵活应对地铁线路的复杂工况,设置节能、稳压、网压支撑、钢轨电位治理、应急电源五种工作模式。通过飞轮储能装置在实际工程的应用案例验证了飞轮储能装置具有良好的稳压效果,平均节能率为11.36%~17.28%,全功率响应频次为31次/h,且经试验验证飞轮储能装置具有应急电源功能。

磁悬浮飞轮NMSS控制及其闭环零点抑制方法

为实现磁悬浮飞轮控制系统无状态观测器下的全状态反馈控制,将最小状态空间增广至非最小状态空间,增广后的状态变量可由控制对象的输入量和输出量直接计算得到。针对跟踪指令为零时前置滤波器失效的问题,在非最小状态空间的基础上引入跟踪指令信号修正,使前置滤波器能正常工作。在相同主导特征值的条件下与最小状态控制PID控制器进行仿真对比,结果表明:即使偏置电流的扰动达到标称值的60%,非最小状态空间下的闭环系统仍能保持镇定,并且该方法对偏置电流扰动的适应性更好;引入跟踪指令信号修正后,有效消除了闭环系统中存在的有限零点,验证了该方法的有效性。