Battery Management System for Electric Drive Vehicles – Modeling, State Estimation and Balancing

Electric-drive vehicles (EDVs) have drawn more and more attention worldwide. As one of the most important parts of EDVs, battery management systems (BMSs) manage the huge amount of battery cells in EDVs and assures their safety. To achieve these goals, researches in BMS, such as battery modeling, battery state estimation, and battery balancing have gained a new vigor. This chapter will review the existing researches and introduce several advances in these areas

A New 95 GHz Methanol Maser Catalog: I. Data

The Purple Mountain Observatory 13.7 m radio telescope has been used to search for 95 GHz (8$_0$--7$_1$A$^+$) class I methanol masers towards 1020 Bolocam Galactic Plane Survey (BGPS) sources, leading to 213 detections. We have compared the line width of the methanol and HCO$^+$ thermal emission in all of the methanol detections and on that basis we find 205 of the 213 detections are very likely to be masers. This corresponds to an overall detection rate of 95 GHz methanol masers towards our BGPS sample of 20%. Of the 205 detected masers 144 (70%) are new discoveries. Combining our results with those of previous 95 GHz methanol masers searches, a total of four hundred and eighty-one 95 GHz methanol masers are now known, we have compiled a catalog listing the locations and properties of all known 95 GHz methanol masers.Comment: 18 pages, 7 figures, 8 tables, accepted for publication in ApJ

Desain Proportional Integral Derrivative (Pid) Controller Pada Model Arm Robot Manipulator

Dalam rangka menuju proses industrialisasi modern di negara Indonesia, harus didukung dengan teknologi yang canggih, contoh nya adalah arm robot manipulator. sebagai pelaku proses produksi sehingga dihasilkan ketepatan,kepresisian, dan kefektifan pada proses produksi. Dengan hal tersebut dibuat sebuah desain kontrol PID pada arm robot manipulator dengan tujuan menghasilkan tingkat presisi dan kestabilan yang lebih baik. Kontroler tersebut didesain, disimulasikan, dan diaplikasikan pada hardware dengan menggunakan software MATLAB/Simulink, kemudian dianalisa kestabilannya dengan metode root locus. Akrilik digunakan sebagai material pada body arm robot. Selanjutnya komponen utama seperti, potensiometer sebagai analog input, motor DC sebagai penggerak setiap link, serta Arduino Mega 2560 sebagai mikrokontroler. Akrilik dipilih karena ringan, kuat dan tahan lama.Dalam penelitian ini akan dilakukan penyempurnaan konstruksi mekanik arm robot manipulator yang sudah ada, pemasangan hardware elektronik, dan pemrograman mikrokontroler dengan menggunakan software MATLAB pada Arduino Toolbox. Dari penelitian yang telah dilakukan, model arm robot manipulator dapat bergerak lebih smooth sesuai dengan input pergerakan potensiometer, dan berada posisi kestabilan saat dianalisa dengan menggunakan root locus

Planck Galactic Cold Clumps at High Galactic Latitude-a Study with CO Lines

Gas at high Galactic latitude is a relatively little noticed component of the interstellar medium. In an effort to address this, 41 Planck Galactic Cold Clumps at high Galactic latitude (HGal; divide b divide > 25 degrees) were observed in (CO)-C-12, (CO)-C-13, and (CO)-O-18 J = 1-0 lines, using the Purple Mountain Observatory 13.7 m telescope. (CO)-C-12 (1-0) and (CO)-C-13 (1-0) emission was detected in all clumps, while (CO)-O-18 (1-0) emission was only seen in 16 clumps. The highest and average latitudes are 71.degrees 4 and 37.degrees 8, respectively. Fifty-one velocity components were obtained, and then each was identified as a single clump. Thirty-three clumps were further mapped at 1 ' resolution, and 54 dense cores were extracted. Among dense cores, the average excitation temperature T (ex) of (CO)-C-12 is 10.3 K. The average line widths of thermal and nonthermal velocity dispersions are 0.19 and 0.46 km s(-1), respectively, suggesting that these cores are dominated by turbulence. Distances of the HGal clumps given by Gaia dust reddening are about 120-360 pc. The ratio of X (13)/X (18) is significantly higher than that in the solar neighborhood, implying that HGal gas has a different star formation history compared to the gas in the Galactic disk. HGal cores with sizes from 0.01 to 0.1 pc show no notable Larson's relation, and the turbulence remains supersonic down to a scale of slightly below 0.1 pc. None of the HGal cores that bear masses from 0.01 to 1 M (circle dot) are gravitationally bound, and all appear to be confined by outer pressure.Peer reviewe

A Novel Method to Balance and Reconfigure Series-Connected Battery Strings

Cell failure and imbalance are critical problems in battery storage systems, especially in series-connected battery strings. The reconfiguration function and the balancing function are both of great importance, but it is very challenging and problematic to own both functions simultaneously. This paper attempts to make contributions on realizing both functions through new circuits and new control strategies. Firstly, a reconfigurable balancing circuit is proposed, which is able to simultaneously balance and reconfigure the battery string. In the circuits, a new way to achieve passive balancing with no bleeding resistor is realized, and the failure cells in the battery string can be bypassed with the same circuits. By taking advantage of fewer switches in the circuits, the method owns the merits of low cost and low system complexity. Secondly, to efficiently balance and reconfigure the battery string, a control strategy is proposed according to the unique structure of the circuits. Thirdly, the reconfigurable balancing circuits are fabricated and an experimental test workbench is established. The reconfigurable balancing circuits and the control strategy are validated in the experimental test workbench. The experimental results indicate that the proposed method is able to realize both the balancing function and the reconfiguration function well, and the performance of the battery string can be maintained and improved significantly. The improvements are 13% and 34% for 4 cell- and 100 cell- series-connected battery strings, respectively

A Method to Simultaneously Detect the Current Sensor Fault and Estimate the State of Energy for Batteries in Electric Vehicles

Recently, State of energy (SOE) has become one of the most fundamental parameters for battery management systems in electric vehicles. However, current information is critical in SOE estimation and current sensor is usually utilized to obtain the latest current information. However, if the current sensor fails, the SOE estimation may be confronted with large error. Therefore, this paper attempts to make the following contributions: Current sensor fault detection and SOE estimation method is realized simultaneously. Through using the proportional integral observer (PIO) based method, the current sensor fault could be accurately estimated. By taking advantage of the accurate estimated current sensor fault, the influence caused by the current sensor fault can be eliminated and compensated. As a result, the results of the SOE estimation will be influenced little by the fault. In addition, the simulation and experimental workbench is established to verify the proposed method. The results indicate that the current sensor fault can be estimated accurately. Simultaneously, the SOE can also be estimated accurately and the estimation error is influenced little by the fault. The maximum SOE estimation error is less than 2%, even though the large current error caused by the current sensor fault still exists

A Novel Multimode Hybrid Energy Storage System and its Energy Management Strategy for Electric Vehicles

This paper proposes a novel topology of multimode hybrid energy storage system (HESS) and its energy management strategy for electric vehicles (EVs). Compared to the conventional HESS, the proposed multimode HESS has more operating modes and thus it could in further enhance the efficiency of the system. The rule-based control strategy and the power-balancing strategy are developed for the energy management strategy to realize mode selection and power distribution. Generally, the DC–DC converter will operate at peak efficiency to convey the energy from the batteries to the UCs. Otherwise, the pure battery mode or the pure ultracapacitors (UCs) mode will be utilized without the DC–DC converter. To extend the battery life, the UCs have the highest priority to recycle the energy and the batteries are isolated from being recharged directly during regenerative braking. Simulations and experiments are established to validate the proposed multimode HESS and its energy management strategy. The results reveal that the energy losses in the DC–DC converter, the total energy consumption and the overall system efficiency of the proposed multimode HESS are improved compared to the conventional HESS

Photovoltaic Power System with MPPT Functionality for a Small-Size Electric Vehicle

Electric vehicles are recognized as the best replacement of petrol vehicles in the future. However, there are several problems hampering their development, such as the short life span of batteries, poor performance of start-up, and a short driving range. In order to resolve these problems, a hybrid power system based on photovoltaic (PV) cells, supercapacitors, and batteries is proposed. This paper focuses on PV cells using a maximum power point track (MPPT) system based on a BUCK chopper circuit. Moreover, a novel MPPT algorithm named sectional variable step climbing (SVSC) algorithm was proposed. To validate the proposed system, two main experiments have been done. The first experiment showed that the MPP of PV cells was tracked perfectly by use of this photovoltaic power system. The second one showed that the efficiency of SVSC was higher than two existing MPPT methods, the climbing algorithm and the open-circuit voltage (OCV) algorithm