Power-balancing instantaneous optimization energy management for a novel series-parallel hybrid electric bus

Energy management(EM) is a core technique of hybrid electric bus(HEB) in order to advance fuel economy performance optimization and is unique for the corresponding configuration. There are existing algorithms of control strategy seldom take battery power management into account with international combustion engine power management. In this paper, a type of power-balancing instantaneous optimization(PBIO) energy management control strategy is proposed for a novel series-parallel hybrid electric bus. According to the characteristic of the novel series-parallel architecture, the switching boundary condition between series and parallel mode as well as the control rules of the power-balancing strategy are developed. The equivalent fuel model of battery is implemented and combined with the fuel of engine to constitute the objective function which is to minimize the fuel consumption at each sampled time and to coordinate the power distribution in real-time between the engine and battery. To validate the proposed strategy effective and reasonable, a forward model is built based on Matlab/Simulink for the simulation and the dSPACE autobox is applied to act as a controller for hardware in-the-loop integrated with bench test. Both the results of simulation and hardware-in-the-loop demonstrate that the proposed strategy not only enable to sustain the battery SOC within its operational range and keep the engine operation point locating the peak efficiency region, but also the fuel economy of series-parallel hybrid electric bus(SPHEB) dramatically advanced up to 30.73% via comparing with the prototype bus and a similar improvement for PBIO strategy relative to rule-based strategy, the reduction of fuel consumption is up to 12.38%. The proposed research ensures the algorithm of PBIO is real-time applicability, improves the efficiency of SPHEB system, as well as suite to complicated configuration perfectly.     

智能双向计量与监控终端设计

Aiming at the problems of bidirectional energy independent measurement,power quality parameter monitoring,distributed power control,power subsidies billing casing by a lot of distributed power access to the smart grid,a review was given on bidirectional energy independent measurement,AMI system,harmonic measurement, communication protocol,energy efficiency management and so on,analyzing the function requirements of smart bidirectional measurement and monitoring terminal,by referencing smart meter design solutions,designed a smart bidirectional measurement and monitoring terminal which is based on 'STM32F207 microcontroller + metering chip” and a variety of communication interfaces. Using FreeRTOS operating system as platform, designed the overall mission, bidirectional energy measurement task,power quality monitoring mission,energy efficiency management tasks,data storage and control tasks flowchart,and used calibration equipment and other related equipment to test its functions. The results indicate that the terminal energy metering meets the accurate requirements, and can achieve real-time gatliering power grid quality,bidirectional communication,bidirectional energy metering and billing and other functions. The system is stable and reliable. [ABSTRACT FROM AUTHOR]     

DEVELOPMENT OF THE ENERGY MANAGEMENT STRATEGY FOR PARALLEL HYBRID ELECTRIC URBAN BUSES

A novel parallel hybrid electrical urban bus （PHEUB） configuration consisting of an extra one-way clutch and an automatic mechanical transmission （AMT） is taken as the study subject. An energy management strategy combining a logic threshold approach and an instantaneous optimization algorithm is proposed for the investigated PHEUB. The objective of the energy management strategy is to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing the engine fuel consumption and maintaining the battery state of charge in its operation range at all times. Under the environment of Matlab/Simulink, a computer simulation model for the PHEUB is constructed by using the model building method combining theoretical analysis and bench test data. Simulation and experiment results for China Typical Bus Driving Schedule at Urban District （CTBDS_UD） are obtained, and the results indicate that the proposed control strategy not only controls the hybrid system efficiently but also improves the fuel economy significantly.     

ENERGY MANAGEMENT STRATEGY FOR PARALLEL HYBRID ELECTRIC VEHICLES

Energy management strategy (EMS) is the core of the real-time control algorithm of the hybrid electric vehicle (HEV). A novel EMS using the logic threshold approach with incorporation of a stand-by optimization algorithm is proposed. The aim of it is to minimize the engine fuel consumption and maintain the battery state of charge (SOC) in its operation range, while satisfying the vehicle performance and drivability requirements. The hybrid powertrain bench test is carried out to collect data of the engine, motor and battery pack, which are used in the EMS to control the powertrain. Computer simulation model of the HEV is established in the MATLAB/Simulink environment according to the bench test results. Simulation results are presented for behaviors of the engine, motor and battery. The proposed EMS is implemented for a real parallel hybrid car control system and validated by vehicle field tests.     

Power Matching and Energy Efficiency Improvement of Hydraulic Excavator Driven with Speed and Displacement Variable Power Source

Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of the speed variable systems have the dynamic response problem when the motor starts with full load or heavy load. To address this problem, a hydraulic accumulator is used to balance the load of the power source for assisting starting of the motor and a matching method combined with speed and displacement control of the pump is proposed to improve the energy efficiency and dynamic performance simultaneously under different working conditions. Also, the power source/valve combined control strategy of an independent metering system is designed to realize flow matching of the whole system. Firstly, a test system is established to study the dynamic performance and energy efficiency of the speed variable power source with an auxiliary accumulator. Working performance and energy consumption of the power source under different rotating speeds and different loads are studied. And then, the hydraulic excavator test rig with the proposed system is constructed. Furthermore, the working performance of the excavator with the speed-fixed and speed-variable strategy are studied comparatively. Results show that, compared with fixed-speed strategy, the electric power consumption during the idle period and partial load condition can be reduced about 2.05 kW and 1.37 kW. The energy efficiency of speed variable power source is about 40%-71%, which is higher than that of the fixed-speed power source by 3%–10%.     

Coordinate Control,Motion Optimization and Sea Experiment of a Fleet of Petrel-Ⅱ Gliders

The formation of hybrid underwater gliders has advantages in sustained ocean observation with high resolution and more adaptation for complicated ocean tasks. However, the current work mostly focused on the traditional gliders and AUVs.The research on control strategy and energy consumption minimization for the hybrid gliders is necessary both in methodology and experiment. A multi-layer coordinate control strategy is developed for the fleet of hybrid underwater gliders to control the gliders' motion and formation geometry with optimized energy consumption. The inner layer integrated in the onboard controller and the outer layer integrated in the ground control center or the deck controller are designed. A coordinate control model is proposed based on multibody theory through adoption of artificial potential fields. Considering the existence of ocean flow, a hybrid motion energy consumption model is constructed and an optimization method is designed to obtain the heading angle, net buoyancy, gliding angle and the rotate speed of screw propeller to minimize the motion energy with consideration of the ocean flow. The feasibility of the coordinate control system and motion optimization method has been verified both by simulation and sea trials. Simulation results show the regularity of energy consumption with the control variables. The fleet of three Petrel-Ⅱ gliders developed by Tianjin University is deployed in the South China Sea. The trajectory error of each glider is less than 2.5 km, the formation shape error between each glider is less than 2 km, and the difference between actual energy consumption and the simulated energy consumption is less than 24% actual energy. The results of simulation and the sea trial prove the feasibility of the proposed coordinate control strategy and energy optimization method. In conclusion, a coordinate control system and a motion optimization method is studied, which can be used for reference in theoretical research and practical fleet operation for both the traditional gliders and hybrid gliders.     

基于线控电动汽车的驱动转向 一体化控制器研究

Aiming at the problem that recently both the driving strategy for the motor in wheel and steering strategy for the electric vehicle were researched independently,the structure,the control system,the motor in wheel driving control system,the independent steering system, the CAN communication network and the power tube isolation drive were studied,and the integrated controller for the electric vehicle was proposed. Experiments on 5 kinds of vehicle working mode were carried out based on the integrated steering controller driver. The steering and electronic diferential control of tlie normal working mode was focused by experiment. The results indicate that tlie integrated controller can meet tlie real time,accuracy and reliability requirements of tlie electric vehicle. [ABSTRACT FROM AUTHOR]     

A New Force Control Strategy Improving the Force Control Capabilities of Standard Industrial Robots

In this paper, a new force control strategy （FineForce） is proposed, which is intended to improve the force control capability of standard industrial robots. The strategy distinguishes between joints with low and high （force control） bandwidth and tries to utilize the individual performance of the robot joints, such that improved results concerning force control can be achieved. The paper describes the FineForce control strategy as well as its laboratory implementation, based on a standard industrial robot. On the basis of experimental investigations, the performance of FineForce is demonstrated and compared to conventional force control strategies. Furthermore the usability of the new strategy in an industrial application is shown by a robot-based grinding process.     

Hydraulic Accumulator-Motor-Generator Energy Regeneration System for a Hybrid Hydraulic Excavator

Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy.     

An Ensemble Application of Conflict-Resolving ART-Based Neural Networks to Fault Detection and Diagnosis

Accurate fault detection and diagnosis is important for secure and profitable operation of modern power systems.In this paper,an ensemble of conflict-resolving Fuzzy ARTMAP classifiers,known as Probabilistic Multiple Fuzzy ARTMAP with Dynamic Decay Adjustment(PMFAMDDA),for accurate discrimination between normal and faulty operating conditions of a Circulating Water(CW)system in a power generation plant is proposed.The decisions of PMFAMDDA are reached through a probabilistic plurality voting strategy that is in agreement with the Bayesian theorem.The results of the proposed PMFAMDDA model are compared with those from an ensemble of Probabilistic Multiple Fuzzy ARTMAP(PMFAM)classifiers.The outcomes reveal that PMFAMDDA,in general,outperforms PMFAM in discriminating operating conditions of the CW system.     

混联式混合动力客车能量管理实时优化算法研究

为提高新型混联式混合动力客车的燃油经济性,制定了一种功率均衡能量管理控制策略。建立动力系统模型并针对其结构特点设计了模式切换规则。通过确定各个功率需求下的电池荷电状态与发动机燃油消耗的关系,将电池功率转化为相应的油耗,以每一时刻的综合燃油消耗量最小为目标,对电池与发动机功率进行实时优化均衡控制。仿真结果表明：电池荷电状态控制在预定的区域内保持平衡,发动机运行工作点在高效区域内,且整车燃油经济性与原型客车和采用规则控制策略相比分别提高了34.18%和13.61%。     

独立运行方式下的微电网能量优化管理

针对独立运行方式下的微电网经济运行和管理问题,提出了独立运行方式下的微电网能量优化管理方法,该方法通过缩减下垂控制单元的基点运行功率范围,使其具有类似于传统发电机组自动发电量控制(AGC)的功率调节裕量,以吸纳实时调度周期内的非计划瞬时波动功率;在每次调度时刻,根据系统净负荷功率大小和可控型微电源的基点运行功率范围之间的关系,采用不同的能量调度策略,并引入负荷竞价策略,增加了切负荷和卸荷控制作为功率调节手段,建立了所涉及的负荷优化分配模型和负荷可中断优化模型。最后,通过一个微电网系统算例验证了该方法的有效性。     

基于CDMA的配电变压器实时监控系统

本文提出构建基于CDMA的配电变压器实时监控系统,通过监测终端实时采集配电线路上变压器的运行参数,以CDMA通信方式传送至监控中心,在监控中心对这些信息进行运算处理,对配变进行远程控制,保证配电变压器的安全运行和经济运行.     

新软件技术在燃料电池客车控制系统中的应用

燃料电池城市客车的部件繁多,结构复杂,包括燃料电池发动机、蓄电池、DC/DC和电动机等多个部件节点,其控制系统多采用复杂的分布式控制系统.该控制系统信息流量大、控制任务复杂、实时性要求高,在开发与运行过程当中对数据监控、故障诊断、程序在线更新、数据传输等都提出了更高的要求.在燃料电池城市客车控制系统研发与装备过程中,采用了OSEK/VDX标准的实时操作系统、硬件在环实时仿真、时间触发控制器局域网(Controller area network, CAN)以及无缝自动代码生成等最新的软件技术,这些新技术的应用,有效地提高了燃料电池客车控制系统的开发效率,降低了系统故障率,并为燃料电池客车的优化控制构建了一个开放的技术平台.     

基于电蓄热与抽水蓄能的风电消纳协调控制策略（英文）

为解决"三北"地区冬季供热期由于热电机组"以热定电"运行约束而导致的严重弃风问题,该文在研究电热负荷与风电出力分布特性以及不同时间尺度风功率波动特性的基础上,提出了基于电蓄热与抽水蓄能的两级协调控制策略。第一级协调控制以系统运行成本最小和风电利用率最大为目标,根据电热负荷和风电预测出力,通过电蓄热与抽水蓄能在调节容量上的优化配置,提高系统运行经济性和风电消纳率;第二级协调控制针对风电出力的实时波动,根据风电计划上网偏差,通过电蓄热与抽水蓄能的协调控制,平抑风电实时波动,提高风电消纳水平。结合甘肃酒泉实际运行的风电场站,所提出的协调控制策略的有效性得到验证。     

区域微电网群两级能量调度策略优化研究

针对现阶段微电网能量管理技术发展趋势,在满足其内部经济调度的基础上,还需要关注微电网间的能量互补机制。对并网型区域微电网群提出了一种两级能量优化调度模型。引入条件风险指标(CVaR)衡量可再生能源与负荷预测误差对调度方案造成的影响,结合微电网运行收益,作为微电网内部能量调度的优化目标;采用多目标粒子群优化算法(MOPSO)进行求解,研究收益风险比作为优化调度策略的筛选指标,提出微电网内部能量优化调度策略;以区域微电网群公共并网点有功功率梯度变化最小化为前提,获得最佳微电网净功率组合方案,由此平抑微电网群对配电网造成的功率波动;考虑电力传输距离制定了微电网间净功率互补机制,提高功率传输效率。算例仿真结果表明,该模型能够合理实现微电网内与微电网间经济运行与功率平衡,为微电网群日前调度计划提供了有效设计流程。     

Fuzzy-Super twisting control implementation of battery/super capacitor for electric vehicles

The present paper deals with a real-time implementation of a novel Fuzzy logic energy management strategy (EMS), applied to a battery–super capacitor hybrid energy system and associated with a permanent magnet synchronous motor (PMSM) which emulates the traction part of an electric vehicle (EV). On the sources side, the fuzzy logic supervisor acts in a smart way to permute smoothly between the various operations modes via an efficient power frequency splitting. In addition, it permits a quite regulation of both the DC bus and the super-capacitor (SC) voltages regardless of the speed profile variations to ensure an optimal power flow to the load and to keep the SC operation in a safe voltage range while providing or absorbing power in transients. On the traction side, a second order sliding mode control called ‘super-twisting’ (ST), associated with a space vector modulation (SVM) strategy is applied to ensure both decoupled torque and flux control under low torque and flux ripples. The assessment of the proposed control techniques is conducted on a small-scale battery/SC/PMSM system, controlled via two dSPACE1104 cards. The obtained experimental results show a smooth operation of the whole system, where the proposed Fuzzy logic supervisor succeeds to provide fast and high performances under different speed levels and ensures the proper functioning of each source while respecting its dynamics. Furthermore, the second order sliding mode controller shows good dynamic performances, where the system arrives to track perfectly the speed profile, under tolerable torque and flux ripples.     

基于Willans Line的双轴驱动混合动力越野车实时能量管理

为了实现混合动力越野车的实时能量管理,建立了其动力系统的动力学模型,提出利用发动机和电机的Willans Line 模型,建立基于WL-ECMS能量管理控制方法的发动机和电机最优输出功率模型。硬件在环试验结果表明,基于WL-ECMS的控制方法可以实现混合动力越野车基本的能量管理,车速跟随误差在合理的范围内,与基于ECMS的能量管理控制方法相比,其百公里油耗仅提高3.03%,与基于规则的能量管理控制方法相比,其百公里油耗低12.07%,且每一个时间步长程序的相对运行时间由基于ECMS方法的100下降到1.65,与基于规则方法的1.07相当,实现了混合动力越野车实时能量管理。     

一种液压挖掘机并联式混合动力系统结构及控制策略

为了能够从理论上对混合动力液压挖掘机进行研究,并从中找出有利于系统节能和降低排放的有效途径,以山河智能SWE230液压挖掘机为原型,分析其动力系统各元件特性,并利用AMEsim软件建立并联式混合动力挖掘机系统的整机仿真模型.通过试验采集挖掘机在典型工况下的功率谱.根据挖掘机的工况特点,提出1种基于工况预测的准定工作点控制策略,并应用于仿真模型.仿真结果表明,所提出的控制策略能有效减小超级电容荷状态(SOC)波动,稳定发动机工作点,提高燃油经济性.