锌空气电池产业化发展模式的探讨

结合锌空气电池自身特点,探讨了锌空气电池产业化发展模式。以电动自行车上使用"电-电混合"的技术方法为市场切入点,建立了可再生的锌空气电池商业发展模式,为能源再生产业奠定基础,这种模式弥补了现有电池市场续驶里程短等缺陷,建立了换电电池商业模式,改变了电池只能充电的传统观念。

A 12bit 300MHz Current-Steering CMOS D/A Converter

The proposed DAC consists of a unit current-cell matrix for 8MSBs and a binary-weighted array for 4LSBs,trading-off between the precision,speed,and size of the chip.In order to ensure the linearity of the DAC,a double Centro symmetric current matrix is designed by the Q2 random walk strategy.To achieve better dynamic performance,a latch is added in front of the current switch to change the input signal,such as its optimal cross-point and voltage level.For a 12bit resolution,the converter reaches an update rate of 300MHz.

HYBRID EXCITATION CLAW-POLE SYNCHRONOUS GENERATOR WITH MAGNETIC CIRCUIT SERIES CONNECTION

To solve the low efficiency of electric excitation claw-pole synchronous generator（EECPSG） and regulate the magnetic field of permanent magnet （PM） claw-pole synchronous generator（PMCPSG）, a novel hybrid excitation claw-pole synchronous generator （HECPSG）with magnetic circuit series connection is proposed. Through the simulation study on the generator using the calculation method for magnetic circuit and 3-D finite element method （FEA）, the appropriate magnet thickness and the number of pole-pairs for the proposed generator are determined. Its off-loading characteristics, load characteristics, and regulation behaviors are investigated. The study shows that the appropriate number of pole-pairs in HECPSG with series magnetic circuits is two, and there exists an optimum magnet thickness. Compared to EECPSG, HECPSG realizes dual-directional control to the excitation current. Moreover, the generator can adjust the output voltage and keep the output voltage stable in a broad load range. Under the condition of same parametes, the motor has higer air-gap flux density and power density.

Model based SOC estimation for high-power Li-ion battery packs used on FCHVs

A model based method which recruited the extended Kalman filter （EKF） to estimate the full state of charge （SOC） of Li-ion battery was proposed. The underlying dynamic behavior of the cell pack was described based on an equivalent circuit comprising of two capacitors and three resistors. Measurements in two tests were applied to compare the SOC estimated by model based EKF estimation with the SOC calculated by coulomb counting. Results have shown that the proposed method is able to perform a good estimation of the SOC of battery packs. Moreover, a corresponding battery management systems （BMS） including software and hardware based on this method was designed.

Mixed Conduction in BaCe0.8Pr0.2O3-α Ceramic

BaCe0.8Pr0.2O3-α ceramic was synthesized by high temperature solid-state reaction. The structural characteristics and the phase purity of the crystal were determined using powder X-ray diffraction analysis. By using the methods of AC impedance spectroscopy, gas concentration cell and electrochemical pumping of hydrogen, the conductivity and ionic transport number of BaCe0.8Pr0.2O3-α were measured, and the electrical conduction behavior of the material was investigated in different gases in the temperature range of 500-900℃. The results indicate that the material was of a single perovskite-type orthorhombic phase. From 500℃ to 900 ℃, electronic-hole conduction was dominant in dry and wet oxygen, air or nitrogen, and the total conductivity of the material increased slightly with increasing oxygen partial pressure in the oxygen partial pressure range studied. Ionic conduction was dominant in wet hydrogen, and the total conductivity was about one or two orders of magnitude higher than that in hydrogen-free atmosphere （oxygen, air or nitrogen）

Effects of ion-ion correlations on surface charge inversion in mixture electrolyte solutions

As the structure of electrical double layer(EDL)is crucial for the transport properties of ions in micro/nanochannels,to demonstrate the effects of the ion-ion correlations on EDL structures in mixture electrolyte solutions,the interaction forces between two mica surfaces immersed in different volume fractions of LaCl3/KCl and LaCl3/MgCl2 mixture solutions with a total ionic strength of 10^-4 mol/L were measured using a surface forces apparatus(SFA).The results reveal that the surface charge of mica surfaces can be inversed at a critical concentration of La^3+ions in electrolyte solutions,due to the correlations between La^3+ions.The addition of monovalent has negligible effects on ion-ion correlations,while the charge inversion was slightly suppressed by introducing the divalent ions.The mechanism of charge inversion in mixture electrolyte solutions was analyzed based on the strongly correlated liquid(SCL)theory.These findings provide implications for understanding the effects of ion-ion correlations on EDL structures,surface charge properties,and ion transportation.

Supervisory control of the hybrid off-highway vehicle for fuel economy improvement using predictive double Q-learning with backup models

This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimize the engine fuel in real-world driving and improve energy efficiency with a faster and more robust learning process.Unlike the existing“model-free”methods,which solely follow on-policy and off-policy to update knowledge bases(Q-tables),the PDQL is developed with the capability to merge both on-policy and off-policy learning by introducing a backup model(Q-table).Experimental evaluations are conducted based on software-in-the-loop(SiL)and hardware-in-the-loop(HiL)test platforms based on real-time modelling of the studied vehicle.Compared to the standard double Q-learning(SDQL),the PDQL only needs half of the learning iterations to achieve better energy efficiency than the SDQL at the end learning process.In the SiL under 35 rounds of learning,the results show that the PDQL can improve the vehicle energy efficiency by 1.75%higher than SDQL.By implementing the PDQL in HiL under four predefined real-world conditions,the PDQL can robustly save more than 5.03%energy than the SDQL scheme.

Microstructure and electrical properties of Lu_2O_3-doped ZnO-Bi_2O_3-based varistor ceramics

Lu2O3-doped ZnO-Bi2O3-based varistor ceramics samples were prepared by a conventional mixed oxide route and sintered at temperatures in the range of 900-1 000°C,and the microstructures of the varistor ceramics samples were characterized by X-ray diffractometry(XRD)and scanning electron microscopy(SEM);at the same time,the electrical properties and V-I characteristics of the varistor ceramics samples were investigated by a DC parameter instrument for varistors.The results show that the ZnO-Bi2O3-based varistor ceramics with 0.3%Lu2O3(molar fraction)sintered at 950°C exhibit comparatively ideal comprehensive electrical properties.The XRD analysis of the samples shows the presence of ZnO,Bi-rich,spinel Zn7Sb2O12 and Lu2O3-based phases.

Identification of dynamic model parameters for lithium-ion batteries used in hybrid electric vehicles

An electrical equivalent circuit model for lithium-ion batteries used for hybrid electric vehicles （HEV） is presented. The model has two RC networks characterizing battery activation and concentration polarization process. The parameters of the model are identified using combined experimental and extended Kalman filter （EKF） recursive methods. The open-circuit voltage and ohmic resistance of the battery are directly measured and calculated from experimental measurements, respectively. The rest of the coupled dynamic parameters, i.e. the RC network parameters, are estimated using the EKF method. Experimental and simulation results are presented to demonstrate the efficacy of the proposed circuit model and parameter identification techniques for simulating battery dynamics.

Study on ultracapacitor-battery hybrid power system for PHEV applications

For the battery only power system is hard to meet the energy and power requirements reasonably, a hybrid power system with uhracapacitor and battery is studied. A Topology structure is analyzed that the uhracapacitor system is connected with battery pack parallel after a bidirectional DC/DC converter. The ultracapacitor, battery and the hybrid power system are modeled. For the plug-in hybrid electric vehicle （PHEV） application, the control target and control strategy of the hybrid power system are put forward. From the simulation results based on the Chinese urban driving cycle, the hybrid power system could meet the peak power requirements reasonably while the battery pack＇ s current is controlled in a reasonable limit which will be helpful to optimize the battery pack＇ s working conditions to get long cycling life and high efficiency.

Optimization of Wind-Marine Hybrid Power System Configuration Based on Genetic Algorithm

Multi-energy power systems can use energy generated from various sources to improve power generation reliability.This paper presents a cost-power generation model of a wind-tide-wave energy hybrid power system for use on a remote island,where the configuration is optimized using a genetic algorithm.A mixed integer programming model is used and a novel object function,including cost and power generation,is proposed to solve the boundary problem caused by existence of two goals.Using this model,the final optimized result is found to have a good fit with local resources.

A High-Quality Preconditioning Technique for Multi-Length-Scale Symmetric Positive Definite Linear Systems

We study preconditioning techniques used in conjunction with the conjugate gradient method for solving multi-length-scale symmetric positive definite linear systems originating from the quantum Monte Carlo simulation of electron interaction of correlated materials. Existing preconditioning techniques are not designed to be adaptive to varying numerical properties of the multi-length-scale systems. In this paper, we propose a hybrid incomplete Cholesky （HIC） preconditioner and demonstrate its adaptivity to the multi-length-scale systems. In addition, we propose an extension of the compressed sparse column with row access （CSCR） sparse matrix storage format to efficiently accommodate the data access pattem to compute the HIC preconditioner. We show that for moderately correlated materials, the HIC preconditioner achieves the optimal linear scaling of the simulation. The development of a linear-scaling preconditioner for strongly correlated materials remains an open topic.

Structure improvement and electrochemical studies of bipolar nickel metal hydride batteries for hybrid electric vehicles

Nickel metal hydride battery in bipolar design offers some advantages for its application as a power storage system for electric and hybrid vehicles. This paper deals with the structure design and electrochemical studies of bipolar Ni/MH batteries for hybrid vehicles. An improvement is applied in bipolar battery design, and such bipolar Ni/MH batteries with 5 sub-cells have been assembled and investigated. Testing results show that bipolar batteries with improved structure have better compression tolerance and cycle performance than conventional ones. In addition, the improved bipolar batteries display excellent large current discharge ability and high power density. As simulating working conditions for hybrid vehicles, the batteries show good stability during pulse cycles, which verifies the possibility of being used as a power storage device on hybrid vehicles.

Supercapacitors and Battery Energy Management Based on New European Driving Cycle

This paper presents a new strategy of embedded energy management between battery and supercapacitors （SC） for hybrid electric vehicles （HEV） applications. This proposal is due to the present trend in the field, knowing that the major drawback of the HEV is the autonomy problem. Thus, using supercapacitors and battery with a good energy management improves the HEV performances. The main contribution of this paper is focused on DC-bus voltage and currents control strategies based on polynomial controller. These strategies are implemented in PICI8F4431 microcontroller for DC/DC converters control. Due to reasons of cost and available components （no optimized）, such as the battery and power semiconductors （IGBT）, the experimental tests are carried out in reduced scale （2.7 kW）. Through some simulations and experimental results obtained in reduced scale, the authors present an improved energy management strategy for HEV.

Modern Electrical Power Source on New System of Dissipation and Renewable Energies Sources

This paper presents some solutions of modem renewable energy system applied actually in dissipation energy source： wind turbine, solar panel battery charge, SSS （support set system）, and standby diesel generator cooperated in series, parallel and hybrid system with main energy system. Its solution enable obtain independent individual energy source in different work exploitations. One of problems concerned with alternative energy source is changes of output voltages and output power dependence of climatic conditions. Possible solution is application of decoupled adjustable speed generation system in renewable energy generation. The decoupled generation system consists of： alternative energy source, internal combustion engine drives permanent magnet generator and DC/AC, or AC/AC converter. Performance of single decoupled generation set is discussed supported by results of laboratory tests. To provide high quality voltage is applied an additional energy storage, made from super capacitor and bidirectional DC/DC convert. Such system performs very stiff voltage in any load condition. Integration of solar battery panels or renewable wind energy system is provided via DC link of the variable speed decoupled autonomous generation system. Results of computer simulation and laboratory experiments are presented in the paper.

The research of controller area network on hybrid electrical vehicle

It is of increasing importance to design and implement vehicle networks for transferring information between electrical control units on Hybrid Electrical Vehicle （HEV）. This paper presents a scheme of using Controller Area Network （CAN） technology to realize communication and datasharing between the electrical units on the HEV. The principle and communication protocol of Electrical Control Units （ECU） CAN node are introduced. By considering different sensitivity of the devices to the latency of data transportation, a new design procedure is proposed for the purpose of simplifying network codes and wiring harness, reducing assembly space and weight, improving assembly efficiency, and enhancing fault-diagnose in auto networks.

Modern Multilevel Control Technique Used in Electric and Hybrid Drive System with Induction Motors

The mathematical model of the modem induction traction motor （TRIM and cutting magnetic circuit traction motor）, supplied with IPM inverter with different control technique is presented in the paper. In electric and hybrid vehicle are applied： FLMC （Fuzzy Logic Mode Control）, SLMC （Sliding Mode Control）, NRMC （Neural Regulator Control）, and Direct Power and Torque Control for Space Vector Modulated inverter （DPTC SVM）. In the special solution of the electric and hybrid vehicle are also applied a Random Switching Frequency Modulation. The control of hybrid vehicle should assure the realization of established transport-assignments in the definite time, at the optimum of energy consumption. One can this realize using. The multi criteria control system. Some results of the computer simulations are presented in the paper. Results of numerical calculation were verified for laboratory model of the electric and hybrid wheel vehicles traction motor.

Research on Hybrid Renewable Energy Systems with Fault Detection Technology

Early and accurate fault detection and diagnosis for renewable energy systems can increase their safety and ensure the continuity of their service. This paper presents a comprehensive review of different fault detection and diagnosis methods for hybrid renewable energy systems consisting of a wind turbine power generator, a PV （photovoltaic） array, a PEM （polymer electrolyte membrane） fuel cell and a battery storage system. The need of batteries to store the generated power from the solar panel, wind turbine or PEM fuel cell is also emphasized. Finally, an overview of the current methods used in the diagnosing of the lead-acid battery degradation is given.

Flexible HVDC Transformer for Next Generation Renewable Energy Industry

The growing demand on non-fossil fuel energy has escalated the desire for mega-scale renewable energy power generation, which can no longer be satisfied solely by relying on onshore renewable energy power plants. Outcomes from a recent project funded by the Sixth European Union Framework Programme （FP6）, Project ＂Upwind＂ concluded that larger offshore wind turbines （i.e., 〉 10 MW） are feasible and cost effective. It will be beneficial for such future large scale renewable energy power generators （i.e., large offshore turbines） and plant （i.e., large offshore wind farms） to have a dedicated high efficiency, robust, flexible and low cost power collection, transmission and distribution technology. Proposed in this paper is a compact and effective hybrid HVDC （high voltage direct current） transformer that allows realisation of a highly robust and financially rewarding next generation multi-terminal HVDC system for future offshore renewable energy power plant. This concept, potentially, allows the elimination or minimisation of the need for a centralised local offshore HVDC platform or substation in each wind farm, solar farm, or tidal farm. This paper discusses the study outcome of the proposed hybrid HVDC transformer and the application of a multi-terminal HVDC system in the renewable energy industry, compared to the existing HVAC and VSC （voltage source converters） type HVDC systems.

Electrical power assisted steering for EVs and HEVs

Electrical power assisted steering (EPAS) is one of the key components, especially for electrical vehicle. It has attracted much attention for their advantages with respect to improved fuel economy and has been widely adopted as automotive power-steering equipment in recent years. EPS (electrical power steering) controllers contain MCU (microprocessor control unit) to implement the complex control algorithms. EPS control strategy development is the core technology of the whole system. To achieve the better performance of driving, both mechanical structures and electrical structures are totally designed as a whole. Model-based development is recommended to software design. There are several trends about EPS’ future, such as high power EPS development, high voltage EPS development and steering-by-wire technology.