Browse Topic: Switches

Items (1,128)
ABSTRACT The need for improved electrical power conversion systems and components is being driven by requirements for higher efficiency, performance, and improved survivability and lethality capabilities on current and future Army platform power system. The U.S. Army Research Laboratory (ARL) has demonstrated a 1200 V, 400 A silicon carbide (SiC) power module based on a standard commercial design. This module uses large area SiC MOS-FETs and diodes and has been evaluated under varying temperatures, loads, and switching frequencies. Throughout the operating range, the module has demonstrated improved efficiency and thermal performance, and higher frequency operation, when compared with similarly rated silicon insulated gate bipolar transistor (IGBT) modules
Geil, Bruce R.Tipton, Charles W.Urciuoli, Damian P.
ABSTRACT This paper reviews advances in application of Silicon Carbide power switch packages as applied to a high power DC/DC Converter prototype. Test data from ongoing testing is presented. In addition the reasons for the ongoing desire to replace silicon in high power electronics devices, and the commercial status of Silicon Carbide devices are briefly presented. SiC power density and efficiency is briefly compared with comparable silicon systems for present-day switch devices
DeBlanc, BrianFriedrich, JensLeslie, EdwardPeschke, Kay
ABSTRACT The design of power distribution systems for modern tanks and fighting vehicles involves a number of challenges, including demands for increasing amounts of electrical power. In response to these needs, Solid State Power Controllers (SSPCs) provide a number of advantages over electromechanical circuit breakers and relays. These include increased reliability, higher volume and weight power densities, lower power dissipation, reduced EMI emissions, very rapid short circuit protection, and precise I2t overload protection. The latter protects wiring, loads and the SSPCs themselves against overheating, while reliably avoiding “nuisance trips” when switching into capacitive or incandescent lamp loads. Further, SSPCs provide capabilities in the area of real time feedback, enabling system-level diagnostics and prognostics, and predictive, condition-based maintenance, thereby providing increased availability and continued mission readiness
Glass, Mike
ABSTRACT Several power converters are presently under development for the US Army TARDEC using all Silicon Carbide (SiC) devices for the power switches. Power modules have recently become available which incorporate multiple SiC devices for both the active and passive switches. Modules fabricated by 2 different vendors (Powerex and MS Kennedy) in a standard half H-Bridge configuration using the same type and number of devices internally (Cree 1200 Volt/20 A DMOSFETs and 1200 Volt/10A SBD) have been obtained and tested. This paper will summarize the main test results including the comparison of the conduction losses, switching losses, switching capability, thermal characteristics, gate drive approach, and physical characteristics (mass/dimensions). As expected, most of the characteristics were very similar between the 2 modules and had reasonable scaling from the individual device characteristics. The differences in the internal connections for the modules result in some differences
Kajs, JohnCastagno, ScottSchupbach, MarceloMitchell, Gavin
This study proposes a multi-mode switching control strategy based on electromagnetic damper suspension (EMDS) to address the different performance requirements of suspension systems on variable road surfaces. The working modes of EMDS are divided into semi-active damping mode and energy harvest mode, and the proposed mode switching threshold is the weighted root mean square value of acceleration. For the semi-active damping mode, a controller based on LQR(Linear Quadratic Regulator) was designed, and a variable resistance circuit was also designed to meet the requirements of the semi-active mode, which optimized the damping effect relative to passive suspension. For the energy harvest mode, an energy harvest circuit was designed to recover vibration energy. In order to reduce the deterioration of suspension performance caused by frequent mode switching in the mode switching strategy, as frequent system switching can lead to system disorder, deterioration of damping effect, and
Zeng, ShengZhang, BangjiTan, BohuanQin, AnLai, JiewenWang, Shichen
In the rapidly evolving landscape of electronic engineering, the reliability of electronic components under varying thermal conditions has emerged as a paramount concern. This paper presents an integrated approach for the reliability analysis of electronic components, emphasizing thermal impacts. Our methodology synergizes computational thermal analysis, experimental stress testing, and Failure Modes, Effects, and Diagnostic Analysis (FMEDA) to offer a comprehensive framework for assessing and enhancing component reliability, specifically focusing on a case study of motorcycle hand control switches. The approach begins with a detailed thermal simulation to identify potential hot spots and thermal gradients across electronic components under different operational scenarios. For the case study, motorcycle hand control switches a critical interface between the rider and the motorcycle's electrical system were subjected to this analysis to predict thermal behavior under varied
Mote, ShwetaJadhav, ShantaramChaudhari, VijayMhaske, Aashay
Crew Station design in the physical realm is complex and expensive due to the cost of fabrication and the time required to reconfigure necessary hardware to conduct studies for human factors and optimization of space claim. However, recent advances in Virtual Reality (VR) and hand tracking technologies have enabled a paradigm shift to the process. The Ground Vehicle System Center has developed an innovative approach using VR technologies to enable a trade space exploration capability which provides crews the ability to place touchscreens and switch panels as desired, then lock them into place to perform a fully recorded simulation of operating the vehicle through a virtual terrain, maneuvering through firing points and engaging moving and static targets during virtual night and day missions with simulated sensor effects for infrared and night vision. Human factors are explored and studied using hand tracking which enables operators to check reach by interacting with virtual components
Agusti, Rachel S.Brown, DavidKovacin, KyleSmith, AaronHackenbruch, Rachel N.Hess, DavidSimmons, Caleb B.Stewart, Colin
Electrification isn't just a matter of switching out the diesel engine for an electric motor. It requires a thorough review of connected systems - particularly the hydraulic system. Using the same components in electric machines as those used in conventional machines often requires more battery power or a larger electric motor. For this reason, OEMs have discovered the need to rethink efficiency and productivity when electrifying machines. MPG Makine Prodüksiyon Grubu learned this firsthand when designing a truck-mounted electric crane for one of its Netherlands-based customers. The Konya, Turkey-based OEM produces truck-mounted hydraulic cranes with folding and telescopic booms as well as aerial work platforms and tree trans-planter machines
Avci, Gökhan
DHT hybrid transmission assembly control system discussed in this paper includes hydraulic control, hybrid mode switching control, shift control, dual motor control, clutch and motor thermal management. The hybrid mode is divided into four modes: the EV mode, the serial mode, the parallel mode and the launch mode. Hydraulic control includes torque-pressure conversion, clutch pressure kiss point adaption, clutch oil filling time adaption. Shift control includes shift type decision, shift sequence control, shift inertia process based on motor intervention. Thermal management includes clutch flow and motor flow distribution. Motor control include the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode. The boost strategy of the hybrid system is based on boost mode management, boost target
Jing, JunchaoZhang, JunzhiLiu, YiqiangWang, ZhentaoXue, Tianjian
In order to achieve seamless mode switching control for hybrid electric vehicles (HEVs) in the event of battery failure, we propose a motor voltage-controlled mode switching method that eliminates power interruptions. This approach is based on an analysis of the dual-motor hybrid configuration's mode switching. We analyze the overall vehicle operation when the high-voltage battery occurs in different hybrid modes. To ensure that the vehicle can still function like a conventional car under such circumstances, we introduce a novel "voltage control" mode. In this mode, instead of operating in its traditional torque control manner, the P1 motor adopts a voltage control strategy. The P1 controller's variable becomes "voltage," and VCU sends the motor's working mode switching request and PCM finishes the mode transition. During system operation, the P1 motor promptly responds to these target voltages to maintain bus voltage within a normal range. The P1 motor voltage is monitored and managed
Jing, JunchaoZhang, JunzhiHuang, WeishanLiu, YiqiangDai, Zhengxing
In order to realize the series-parallel switching control of hybrid electric vehicle (HEV) with dual-motor hybrid configuration, a method of unpowered interrupt switching based on the coordinated control of three power sources was proposed by analyzing the series-parallel driving mode of the dual-motor hybrid configuration. The series to parallel switching process is divided into three stages: speed regulation stage, clutch combination and power source switching. The distribution control of speed regulating torque is carried out in the speed regulating stage. The speed adjustment torque is preferentially allocated to the power source of the input shaft (engine and P1) to carry out the lifting torque. Due to the high speed adjustment accuracy and fast response of the P1 motor, the input shaft is preferentially allocated to P1 for speed adjustment, that is, the torque intervention of P1. If the speed control torque exceeds the intervention capacity of P1, then it is allocated to the
Jing, JunchaoZhang, JunzhiLiu, YiqiangHuang, WeishanDai, Zhengxing
The paper introduces two methods for controlling motor voltage. One method requires the implementation of boost hardware, while the other allows for voltage control in battery failure mode without any additional hardware requirements. The boost voltage strategy for the hybrid system is based on managing boost modes, determining target voltages, and implementing PI control. The boost mode control includes different modes such as initial mode, normal mode, shutdown mode, and fault mode. Determining the boost target voltage involves regulating the boost converter with variable voltages depending on the operating states of the motor and generator. The second voltage control method without boost hardware is proposed in order to ensure that the vehicle can still function like a traditional car even under abnormal conditions of high-voltage battery failure in micro-mixing systems. In this mode, instead of conventional torque control, the generator operates in a voltage control mode where
Jing, JunchaoSun, XudongLiu, YiqiangHuang, Weishan
This paper analyzes the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode, battery heating mode and boost mode. The boost strategy of the hybrid system is based on boost mode management, boost target voltage determination and boost PI control. The specific content is as follows: Boost mode control. Boost mode includes initial mode, normal mode, off mode and fault mode. Boost target voltage is determined. Boost converter is controlled by variable voltage, which depends on the operation status of the motor and generator.. In order to improve the overall performance of the voltage control strategy, the voltage control strategy of the boost converter is dynamically
Jing, JunchaoHuang, WeishanLiu, YiqiangDai, ZhengxingZhang, Junzhi
Wound rotor synchronous machines (WRSM) without rare-earth magnets are becoming more popular for traction applications, but their potential in drive performance has not yet been fully explored. This paper presents a Pulse Width Modulation (PWM) scheme optimization procedure to minimize motor and inverter losses. It leverages different PWM schemes with different PWM switching strategies and switching frequencies. First, a generic PWM-induced motor loss calculation tool developed by BorgWarner is introduced. This tool iteratively calculates motor losses with PWM inputs across the entire operating map, significantly improving motor loss prediction accuracy. The inverter losses are then calculated analytically using motor and wide-bandgap (WBG) switching device characteristics. By quantifying these various scenarios, the optimal PWM scheme for achieving the best system efficiency across the entire operating map is obtained. The PWM-induced motor loss characteristics, the system loss
Ma, CongTyckowski, Joseph
To realize the accurate tracking of the vehicle speed in the process of vehicle speed tracking, a neural network adaptive robust output feedback control (NAROFC) method for the driving robot is proposed. Firstly, considering the dynamic modeling error of the mechanical leg and the time-varying disturbance force, the dynamic model of the driving robot is established. Besides, an Extended State Observer (ESO) is designed to estimate the uncertainty and constant disturbance of modeling parameters in the system. In addition, the recurrent neural network (RNN) is used to estimate the time-varying disturbances existing in the system. Finally, the system control rate is redesigned with an ESO-designed adaptive robust controller, and the switching controller is combined to realize output feedback control. The stability of the designed controller is proved by Lyapunov theorem. The experiment results show that the designed mechanical leg controller has higher tracking accuracy of mechanical legs
Shao, LinChen, Gang
Model-based developments have been introduced to reduce the development time for vehicle systems. Various model-based tools, including MATLAB and Simulink, have been introduced, and each vehicle component uses different tools to model assets. This makes the system complex and reduces the simulation efficiency because of the need for interfaces or converters when reusing model assets and combining parts. However, machine learning, in which neural nets are pretrained to make inferences in real time, is being applied to automatic driving and applications such as object recognition. This study developed a system in which the inputs and outputs assigned to a model were trained using neural nets, and the trained neural nets were combined with UML: Unified Modeling Language. A previous UML integration proposal integrated C/C++ code automatically generated from the models. Therefore, the previous proposal made limited use of modeling tools with automatic code generation capabilities. The
Arai, Masatoshi
Reliable and safe Redundant Steering System (RSS) equipped with Dual-Winding Permanent Magnet Synchronous Motor (DW-PMSM) is considered an ideal actuator for future autonomous vehicle chassis. The built-in DW-PMSM of the RSS is required to identify various winding’s faults such as disconnection, open circuit, and grounding. When achieving redundant control through winding switching, it is necessary to suppress speed fluctuations during the process of winding switching to ensure angle control precision. In this paper, a steering angle safety control for RSS considering motor winding’s faults is proposed. First, we analyze working principle of RSS. Corresponding steering system model and fault model of DW-PMSM have been established. Next, we design the fault diagnosis and fault tolerance strategy of RSS. Considering the difference in amplitude frequency characteristics of phase current during DW-PMSM winding faults, the Hanning window and Short-Time Fourier Transform (STFT) is
Zhao, JianDang, RuijieWu, HangzheZhu, BingChen, Zhicheng
The bi-stable phenomena of the Ahmed model were experimentally studied at different rear slant angles (31.8 °, 42 °, 50 °, 60 °, 75 °, 90°) and different Reynolds numbers (9.2 × 104, 1.84 × 105, 2.76 × 105). The analysis of pressure gradients both on the base and slant indicate that no bi-stable phenomena were observed at different Reynolds numbers when the slant angle was less than or equal to 50°. However, for the rear slant angles greater than or equal to 60°, the pressure gradients consistently shift between two preferred values at various Reynolds numbers, indicating the presence of bi-stable behavior in the spanwise direction. Therefore, the critical angle for the appearance of bi-stability in the Ahmed model lies within the range of 50° to 60°, and the existence of bistable behavior remains unaffected by the Reynolds number. As the slant angle increases, the switching rate decreases significantly until the angle is greater than 60°. Furthermore, with an increase in Reynolds
Bai, HuanchengXia, ChaoYu, LeiFan, YajunJia, QingYang, Zhigang
A multiple output dynamically adjustable capacity system (MODACS) is developed to provide multiple voltage output levels while supporting varying power loads by switching multiple battery strings between serial and parallel connections. Each module of the system can service either a low voltage bus by placing its strings in parallel or a high voltage bus with its strings in series. Since MODACS contains several such modules, it can produce multiple voltages simultaneously. By switching which strings and modules service the different output rails and by varying the connection strategy over time, the system can balance the states of charge (SOC) of the strings and modules. A model predictive control (MPC) algorithm is formulated to accomplish this balancing. MODACS operates in various power modes, each of which imposes unique constraints on switching between configurations. Those constraints are mathematically formalized so that MPC can be applied to minimize predicted SOC differences
Kang, Jun-MoRich, Dave
Researchers have developed a fluid switch using ionic polymer artificial muscles that operates at ultra-low power and produces a force 34 times greater than its weight. Fluid switches control fluid flow, causing the fluid to flow in a specific direction to invoke various movements
Photoelectric (PE) sensors represent a discrete sensor technology widely used throughout industry. Also called photoelectric switches or photoeyes, they use the presence or absence of light to provide an on/off output to supervisory automation and monitoring systems (Figure 1). Although the technology has been in use for many years, there are many device configurations and some recent advancements worthy of note
The switching and coupling of the power source during mode switching of hybrid continuously variable transmission (CVT) vehicles lead to interruptions and sudden changes in power system output torque, which is a key factor affecting driving comfort. To address this issue, the following steps were taken: Firstly, based on the logical threshold energy management strategy, the conditions for mode switching in hybrid CVT vehicles were analyzed. Next, a dynamic model of the clutch engagement process was established, and a double fuzzy PID control strategy for engine speed and clutch pressure was formulated. Then, a dynamic coordination control strategy, combining “engine speed and clutch pressure double fuzzy PID control” with coordinated control of motor torque, was proposed. Finally, the proposed control strategy was simulated and verified. The aim of this approach is to mitigate interruptions and sudden changes in power system output torque during mode switching, thereby improving
Liu, WenChangFu, BingLiu, JingangZhao, YouhongXiong, Jipeng
This document examines the most important considerations relative to the use of proximity sensing systems for applications on aircraft landing gear. In general, the information included are applicable to other demanding aircraft sensor installations where the environment is equally severe
A-5B Gears, Struts and Couplings Committee
Manufacturers of automation components have long made pneumatic valve terminals with IP65 and IP67 ratings that can be mounted anywhere on a machine. This is particularly useful for connecting valves as close to pneumatic actuators as possible. Doing so shortens the length of tubing, reduces the occurrence and severity of leaks, and increases actuator performance by shortening cycle times. Decentralized valve terminals communicate with the machine controller or PLC via an industrial Ethernet network. In addition to valves, terminals are configured with input and output modules to allow for easy connection of sensors, switches, and other field-level devices to the industrial network
The fast dynamic response is a vital requisite for the operation of automotive drives. Various control schemes for electric vehicles (EV) have been proposed over time, and vector control is one of the popular techniques among them. Direct Torque Control (DTC) and Model Predictive Current Control (MPCC) were some of the vector control methods analyzed for their ripples in flux and torque, which in turn affect the performance of the EV is discussed in this paper. The DTC method uses the predefined voltage vector (VV) table to decide the Active voltage vector adjacent to the reference voltage vector from the table; this can also improve the flux response and torque ripple. Furthermore, the switching frequency reduction can be made by incorporating the null voltage vector in the switching sequence. The MPCC is employed for the PMSM machine model to reduce the error between the assumed reference and predicted value using the cost function by choosing one optimum vector. A modified MPCC
R, Nisha RexlineR, Rajarajeswari
Fuel cells’ soft output characteristics and mismatched voltage levels with subordinate electrical devices necessitate the use of DC/DC converters, which are an important part of the power electronic subsystem of the fuel cell system. The staggered parallel Boost topology is commonly employed in fuel cell DC/DC converters. This paper focuses on the control characteristics of the two-phase interleaved parallel Boost topology in the context of a fuel cell system. Specifically, we derive the small-signal model and output-control transfer function of the topology, and design a controller based on frequency characteristic analysis. Our proposed controller uses a cascaded double-ring structure and supports both constant current and constant voltage switching modes. To evaluate the effectiveness of our proposed control strategy, we conduct simulation and prototype testing. The simulation and DC/DC converter prototype are configured according to the output characteristics of the fuel cells, and
Ma, TiancaiLiu, QiLinXie, Jiaojiao
In recent years, efforts to reduce CO2 emissions (carbon neutrality) have accelerated worldwide. In the aluminum manufacturing industry, CO2 emissions can be reduced by switching the raw materials of choice; from virgin ingots to recycled ingots. However, the possible characteristic change accompanying the usage of impurity-ridden recycled ingots severely limits its applications, which also limits its potential contribution to carbon neutrality. Determining how impurity elements present in recycled ingots can affect the function of manufactured components is a necessary first step towards expanding the usage of recycled ingots. In this study, we aimed to apply recycled ingots to the monolithic cylinder made of hypereutectic Al-Si alloy and investigated how impurity elements in recycled ingots affect properties (especially seizure characteristic). Die-cast cylinders using virgin and recycled ingots were manufactured and their properties were investigated. The elements that increased in
Owada, AtsushiSuzuki, Takaharu
Worldwide awareness surrounding the need for hygiene was escalated to the extreme by COVID-19. Now that the pandemic’s beginning is a few years in the past, designers and OEMs for machinery and other user-facing equipment are investigating ways to provide an adequate user interface, while minimizing the need for people to touch the controls
Austenitic stainless JIS SUS316L (16Cr–12Ni–2Mo) steel equivalent material that offers excellent hydrogen embrittlement resistance is used for the high pressure hydrogen pathways in FCEVs. However, there is a need to switch to less expensive material. This paper proposes a technique to evaluate hydrogen embrittlement simulated in high-pressure hydrogen environments based on the use of cathode charging and slow strain rate testing (SSRT) at atmospheric pressure, while also providing an analysis of the hydrogen embrittlement mechanism. At the same time, it presents an evaluation of hydrogen embrittlement resistance of ferrite material, a candidate low-cost material
Suzuki, RyojiMatsume, YuriKatori, Noriaki
To address the Multiple Input Multiple Output (MIMO) control problem of air-path system in the combustion mode switching process of diesel engine, the transient control strategy of air-path system needs to be studied. A universal sliding mode controller suitable for all operating conditions was proposed to control the intake state during the transient combustion mode switching process. Therefore, the structure of the MIMO controller was greatly simplified. At the same time, a control-oriented numerical model was established to test the control system performance. It shows that the novel controller can effectively control the transient intake state, especially during the mode switching process
Leng, LingChen, TianyuShi*, LeiDeng, KangyaoQu, Shuan
NASA’s Watts on the Moon Challenge is seeking solutions to transfer at least 1.065 kW power from a 120 V dc source to a 24-32 V dc load over a 3-km distance under the same environmental conditions as the Lunar surface (i.e., 77 K temperature and 1 mTorr pressure). The selected solution from the author’s team proposed utilizing two modular multilevel Gallium Nitride (GaN) based isolated dc-dc converters to connect the 120 V dc source with the 24-32 V dc load bank via 1.5 kV rated dc transmission lines. The modular multilevel converters feature frequency multiplication, high step-down voltage ratio and low device voltage stress. In the converters, GaN gate injection transistor (GaN GIT) and GaN High-Electron-Mobility Transistor (GaN HEMT) devices are chosen as switching devices, due to the merits of lower power loss, radiation hardness and ability to work under cryogenic and vacuum conditions. In addition, LiFePO4 battery based energy storage with a power condition system is added in
Yao, YuzhouZhang, ZhiningFan, JunchongAdina, NihanthBharmal, NaeemShah, SiddhantZhang, JesseShi, YifanHu, PhD, BoxueFu, PhD., PengyuWang, PhD., Jin
In recent years, the use of high-power inverters has become increasingly prevalent in vehicles applications. With the increasing number of electric vehicle models comes the need for efficient and reliable testing methods to ensure the proper functioning of these inverters. One such method is the use of Hardware-in-the-Loop (HiL) environments, where the inverter is connected to a simulated environment to test its performance under various operating conditions. HiL testing allows for faster and more cost-effective testing than traditional methods and provides a safe environment to evaluate the inverter’s response to different scenarios. Further, in such an environment, it is possible to specifically stimulate those system states in which conflicts between the lines arise regarding the ideal system parametrization. By combining HiL testing with design-of-experiments and modelling methods, the propulsion system can hence be optimized in a holistic manner. In the past, such approaches have
Kiss, GergelyDuchi, FrancescoSteinhaus, Tim
Rice University’s Boris Yakobson and collaborators uncovered a property of ferroelectric 2D materials that could be exploited as a feature in future devices. Because they bend in response to an electrical stimulus, single-layer ferroelectric materials can be controlled to act as a nanoscale switch or even a motor, research published in ACS Nano shows
While machine-learning-based methods suffer from a lack of transparency, rule-based (RB) methods dominate safety-critical systems. Yet the RB approaches cannot compete with the first ones in robustness to multiple system requirements, for instance, simultaneously addressing safety, comfort, and efficiency. Hence, this article proposes a decision-making and control framework which profits from the advantages of both the RB and machine-learning-based techniques while compensating for their disadvantages. The proposed method embodies two controllers operating in parallel, called Safety and Learned. An RB switching logic selects one of the actions transmitted from both controllers. The Safety controller is prioritized whenever the Learned one does not meet the safety constraint, and also directly participates in the Learned controller training. Decision-making and control in autonomous driving are chosen as the system case study, where an autonomous vehicle (AV) learns a multitask policy
Aksjonov, AndreiKyrki, Ville
Pulse Width Modulation or PWM has been widely used in traction motor control for electric propulsion systems. The associated switching noise has become one of the major NVH concerns of electric vehicles (EVs). This paper presents a multi-disciplinary study to analyze and validate current ripple induced switching noise for EV applications. First, the root cause of the switching noise is identified as high frequency ripple components superimposed on the sinusoidal three-phase current waveforms, due to PWM switching. Measured phase currents correlate well with predictions based on an analytical method. Next, the realistic ripple currents are utilized to predict the electro-magnetic dynamic forces at both the motor pole pass orders and the switching frequency plus its harmonics. Special care is taken to ensure sufficient time step resolution to capture the ripple forces at varying motor speeds. Furthermore, the dynamic ripple forces are applied to excite the structure paths including a
He, SongGong, ChengZhang, PengChang, LeKoch, BenjaminGSJ, Gautam
Imagine a home computer operating one million times faster than the most expensive hardware on the market. Now, imagine that level of computing power as the industry standard
Electrical switches of all types activate circuits, send information, and initiate actions. An inertial switch is one that is triggered to activate at a specific acceleration threshold. No power is consumed until the switch is ‘awakened’ by the relevant event, making it ideal for ultra-low power (ULP) and remote applications
To overcome the shortcoming that vehicles with multiple steering modes need to switch steering modes at parking or very low speeds, a dynamic switch method of steering modes based on MOEA/D (Multi-objective Evolutionary Algorithm Based on Decomposition) was proposed for 4WID-4WIS (Four Wheel Independent Drive-Four Wheel Independent Steering) electric vehicle, considering the smoothness of dynamic switch, the lateral stability of the vehicle and the energy economy of tires. First of all, the vehicle model of 4WID-4WIS was established, and steering modes were introduced and analyzed. Secondly, the conditions for the dynamic switch of steering modes were designed with the goal of stability and safety. According to different constraints, the control strategy was formulated to obtain the target angle of the active wheels. Then aiming at the smoothness of the dynamic switch, the active wheel angle trajectory was constructed based on the B-spline theory. And the MOEA/D algorithm was used to
Qiao, YiranChen, XinboLi, Ran
Automotive megatrends such as connected, autonomous and electrified vehicles are driving penetration of automotive electronic technology in every vehicle subsystem. However, these electronic units need to be interfaced with input/output devices from outside world. The same need to be interfaced with a robust and reusable architecture conforming to automotive norms. When generic electronic control units (ECUs) need to be reused across diverse vehicle families and segments, it is desirable that every ECU pin interfaced with the outside world needs to be capable of performing multiple tasks. This is particularly true of digital outputs (such as solenoids, lamps, on/off motors etc.) and digital inputs (such as command switches, pushbuttons, pressure switches, thermal switches etc.) Current smart switch peripheral ICs can be used only as outputs and cannot be configured as inputs whenever demanded by application requirements. Also, these smart switch architectures provide conservatively
Vaidya, Vishwas Manohar
Aiming at the problem of braking shock caused by the inconsistent response time of the inner motor (IM), the outer motor (OM) and the hydraulic brake when the regenerative braking mode of dual-rotor in-wheel motor (DRIWM) is switched, this paper proposes a U-shaped transition coordinated control strategy for the DRIWM. Ensure that the total braking torque can be smoothly transitioned when any one or more of the hydraulic braking torque, the braking torque of the IM and the braking torque of the OM enter/exit braking. The dynamic model of electric vehicle (EV) with DRIWMs is established, the division of braking mode is based on the principle of optimal DRIWM system efficiency, and the U-shaped transition coordinated controller of DRIWM is designed. Finally, two cases of switching the IM single braking mode to hydraulic braking mode and OM and hydraulic coordinated braking mode switching to compound braking mode are taken as examples to verify. The results show that, compared with the
leng, FeiHe, Ren
In general, automatic braking uses an electric stability control (ESC) hydraulic unit that can automatically increase the hydraulic pressure in the wheel cylinder (hereinafter called wheel pressure), independent of the driver’s braking operation. The hydraulic unit should have sufficient pressure response to apply autonomous emergency braking (AEB). It was necessary for the hydraulic unit to have a high flow rate for the pressure response. To satisfy the performance requirements of the AEB, a brushless motor, which has a high maximum rotational speed and good response, is adopted for the hydraulic unit. Furthermore, sensorless control, which does not require a rotation angle sensor, has been developed so that the motor size can be small and common to conventional units. The developed sensorless control can switch the driving methods in three states: pre-rotation, low speed, and high speed. In the pre-rotational state, the magnetic poles are judged to quickly determine the initial
Kawamura, HikaruKokubo, KoichiNaito, MasayukiIida, TakanoriTakahashi, AtsushiTakahashi, Tomoya
An improved control method of automatic emergency braking (AEB) for rear-end collision avoidance is proposed, which combines the advantages of a time-to-collision (TTC) control algorithm and professional driver emergency braking behavior. The TTC control algorithm mostly adopts phased braking, and although it can avoid collision effectively, the braking process is radical and brake comfort is poor. The emergency braking system with professional driver fitting (PDF) has good comfort and can also avoid collision successfully. However, its brake trigger time is too early, which leads to the stopping distance being too large under high-speed conditions and affects the road utilization. By combining the advantages of the two control methods, an improved control algorithm for AEB is proposed. When the TTC value is not greater than a predetermined limit, the PDF control switch will be closed to avoid collision. Through the Matlab/Simulink and CarSim co-simulation platform, the European New
Lai, Fei
The “inter-process cooperation and switching information” is a smart cockpit essential technique. In order to reach the goal of hundreds of processes cooperation and switching information on crossing operating system running on different CPU, this paper sets up a method to implement General IPC of smart cockpit based on AE. By giving perspective of AUTOSAR AE protocols, analyzes possibility to use SOME/IP and DoIP as unified protocol of General IPC based on AE, then tries to deploy SOME/IP and DoIP on POSIX operating system. After that designs smart cockpit prototype, and states the implementation principle of General IPC methods and events over detail. Describes “simultaneously flash two ECUs on double CANs” this operation scenario and abstracts SCFEM and decomposes requirements of the operation scenario to API level items. Use General IPC design ideas and measurements to design the method fun0() as well as the event event0() and use FIDL/FDEPL of CommonAPI to declare them. At last
Xia, BaohuaQian, GuopingSun, YutongWu, XibinLu, ZhenghuaHu, Mengyong
This document defines the test procedures and performance limits of steady state and transient voltage characteristics for 12 V, 24 V, or 48 V electrical power generating systems used in commercial ground vehicles
null, null
Communications systems using higher-frequency electromagnetic waves can transfer more data at faster rates but lack network components to handle these higher bandwidths. Sugar-cubesized blocks of an electromagnetic material can rapidly switch functionality to perform the varied tasks needed to support a network with carrier frequencies of over 100 GHz. The miniscule-scale architecture concealed within the sugar cube blocks generates multiple channels operating simultaneously at different frequencies. Basically, this allows multiple conversations to occur over the same network, which is the heart of highspeed wireless communications
Proton exchange membrane (PEM) fuel cells produce a large amount of waste heat while generating electricity through electrochemical reactions, making them suitable for driving combined heating and power (CHP) systems. According to the hourly thermal and electric loads in a two-story villa in Shanghai in summer, a CHP system based on PEMFC with a lithium-ion battery energy storage system and water tank heat storage system is proposed in this paper. The model of CHP system was established on MATLAB/Simulink platform. Switching control strategy and fuzzy control strategy were designed by using electric following strategy, and the CHP system model was simulated and analyzed under the same heat load and electricity load respectively. Simulation results show that the CHP system under the switching control strategy cannot provide heat when the fuel cell is shut down, and the battery in the CHP system under the fuzzy control strategy has the risk of overcharging. Therefore, this paper proposes
Ma, TiancaiWang, HaolinLi, RuitaoYao, NaiyuanYao, Yao
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