Automotive Alternator Research Articles

Thermal and electrical performance analysis of a lightweight micro CHP system for recreational vehicles

For comfortable use of a Recreational Vehicle (RV), there is a need to supply electrical energy to recharge the batteries and supply the installed equipment, as well as thermal energy, for hot water and ambient heating. A conventional solution for supplying electrical energy is the installation of photovoltaic modules combined with connection to an electrical grid, when possible. Water heating is generally done using a passage gas heater or hybrid gas/electric storage heater. Imported vehicles have gas heating and many other vehicles have diesel heaters. To develop an alternative to currently available energy supply methods, this work proposes the creation of a cogeneration system for RVs. From a literature review, a research gap was identified in relation to micro CHP devices for RVs. In the development of this work, a micro CHP prototype was created, with 980 W of maximum electrical power, consisting of a single-cylinder internal combustion engine, an automotive alternator and heat exchangers for heat recovery. The prototype was enclosed and instrumented, allowing to evaluate the thermal power obtained in water flowing through exhaust gases, lubricating oil and cooling air heat recovery systems, in addition to measuring the electrical power of the alternator. Operational tests were carried out with 46 different test conditions, combining variations in the engine speed (N) and in electrical load. The prototype electrical efficiency reached 10.18 % ±0.2 % at 3008 rpm with 83 % load. The maximum electrical power was 0.746 kW±0.015 kW at 3637 rpm and 100 % load. The maximum thermal energy recovery rate was 3.267 kW±0.039 kW. Utilization factor reached 65.57 % ±0.33 % at 3208 rpm with 63 % load. Compared to traditional means of providing electrical power and thermal power for RVs, the prototype proved to be more advantageous when the demand is for electrical power and space heating. However, for conditions in which the demand is for electrical power and water heating, or just electrical power, the current solutions available are still more efficient.

Development of a small wind turbine for stand-alone system in rural environment. Reuse and recycling of electric motors.

This paper studies the feasibility of using small electrical machines (e.g. automotive alternator, induction motors of domestic applications or electrical motors of some industrial application) as low cost generators for small wind turbine or small hydro power; its transformation in generators is not difficult. The objective is to provide a comparison among permanent magnet synchronous generator PMSG with different topologies (rotor configurations). The analysis was performed using FEMM-2D simulation software, which is based on finite element method. Small wind and hydro power systems are very attractive to support the energy demand for rural areas or developing countries where the electrical microgrid infrastructure is limited. Claw-pole automotive alternators can provide low cost alternative to permanent magnet synchronous generators for small wind and hydro turbines applications. The objective is the integration of hybrid energy conversion systems in microgrids and the development of small stand-alone systems in rural environment.

Remanufacturing benefit comprehensive evaluation for an automotive alternator based on the fuzzy analytic hierarchy process

Remanufacturing benefit comprehensive evaluation for an automotive alternator based on the fuzzy analytic hierarchy process

Optimization Approaches and Techniques for Automotive Alternators: Review Study

Optimization and improvement of the electrical system are applied to cope with the increased demand for electrical power in the vehicular system; they must be carried out in many ways to ensure that the vehicles are provided with the necessary electricity for their performance work electrical equipment. This paper reviews the various optimization approaches for the alternator used in automotive applications and discusses the advantages and disadvantages of each method. The optimization is achieved to the field excitation current that influences the alternator output voltage, and the other techniques designed a controller to optimize the output power of the alternator using power electronic converters. The most suitable approaches are those approaches that use real-time optimization and self-optimization methods. Combining the above two methods can achieve the best results, higher efficiency, stable performance, and a large amount of power produced by the alternator.

Optimal Operation of Automotive Electrical System with Photovoltaic Generation and Three-level Battery Management Scheme

Abstract: For many years, the electrical power requirements in Automotive Electrical System (AES) have been quickly increasing and are predicted to continue to climb. This trend is being pushed by the introduction of a slew of new vehicle features. The constant growth in power needs is stretching the limitations of current automotive power generation and control technologies, stimulating the development of higher-power and higher-voltage electrical systems and components. Electrical power on a vehicle is not free. It comes as a direct result of consuming fuel within the engine to drive the alternator. With a typical engine efficiency of 44% and with present fuel costs this leads to onboard electrical power costs 4 times more than a typical household utility rate. Global oil and gas resource depletion, as well as environmental concerns, have prompted the automobile industry to build more efficient and eco-friendly cars in order to minimize fuel use and safeguard the environment. In our proposed Automotive Electrical system configuration, we have an AES system which is powered by an automotive alternator and battery combination where the alternator is driven by an IC engine and we have a hybrid energy system using a Rooftop PV array with a battery management system (BMS). We discovered that during the off state, the whole load of the automobile is dependent on the 12Vlead acid battery for power, which causes the SOC to drop dramatically. As a result, the suggested model will include a flexible thin-film solar PV module positioned on the rooftop, which will be supported by a Maximum Power Point (MPPT) Tracking charge controller and will deliver energy to recharge the extra battery and meet the electrical requirements when the vehicle is stationary. When the vehicle is in motion, the existing alternator in the car's electrical system takes over the battery charging requirements, by this way, we can meet the electrical requirements of AES without running the engine for a long time by consuming fuel. The proposed model specialty is investigated using MATLAB/Simulink and compared with existing methods. Keywords: Automotive Electrical System (AES), Internal Combustion Engine (ICE), Hybrid Energy System, Rooftop PV array, Maximum Power Point Tracking (MPPT).

Experimental investigation on the alternator charging capacity for automotive applications

This research paper investigates the use of an automotive alternator on an experimental stand to evaluate the capacity to load the battery and produce electricity for car systems. The efficiency was calculated by measuring the electric power supplied to the battery for different regimes of speed. Various aspects regarding the efficiency of energy conversion by using an alternator were also discussed. The stand uses an electric motor with various transmission ratios to rotate the alternator. The speed was recorded with a digital tachometer and the energy consumption of the electric motor with a digital wattmeter. The results obtained showed that the increase in alternator speed generated more electricity and improved the load of the battery.

Rotational Speed Detection for the Automotive Alternator With Low Loss Rectifier in Self-Start

Rotational speed detection is important for alternator-voltage-regulator (AVR) to starts-up and generates regulated electric power for vehicles. However, the rotational speed detection in standby mode for self-start is challenging with low loss rectifier, such as the Schottky diode. In this paper, a novel rotational speed detection method by sensing phase voltage or field voltage at specific modes is proposed to solve the issue without extra wiring or external components. The analysis of phase voltage in standby mode considering rectifier leakage current explains the challenges of conventional detection. The derivation of field voltage in standby mode with ANSYS Maxwell simulation verifies the proposed method. The experimental platform with a three-phase six-pole pairs alternator verified that the proposed method can detect rotational speed even in self-start and low speed of 200 rpm.

Novel coupled analysis methods of automotive alternators considering synchronous rectification circuit

PurposeThe purpose of this paper is to develop a novel coupled analysis method for synchronous rectification alternators.Design/methodology/approachAn ideal diode module is embedded in a rectification circuit. The resistance of the diode module is set such that it is equal to the on-resistance of the MOS-FET modules in the generation mode. In a mode without power generation, the motor voltage is less than the bus voltage; a sufficiently large value is defined for simulating the infinite resistance.FindingsBecause there is no need to decide the switch timing in advance, only one round of coupled analysis is needed to evaluate the synchronous rectification alternators.Research limitations/implicationsAs limited case study is denoted in this paper, much more case studies are needed to be discussed.Practical implicationsBy using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.Social implicationsBy using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.Originality/valueIn the proposed methods, the definition of diode module differs from that of a conventional coupled analysis.

A Novel Synchronous Rectification With Directly Frequency Tracking for Automotive Alternator

Few practical products of synchronous rectification (SR) in the automotive alternator has been reported, though the driving technology of SR is abundant. Continuously and statistically changing switch frequency caused by rotor speed poses a significant challenge to the driving circuit design under the specified application area. In this article, a directly frequency tracking (D-FT) method is first proposed to ensure the switching tube's safe conduction time adapted to the rotor speed, making the SR immune to circuit oscillation or spurious ringing. The proposed self-driven circuit generates correct gate driving signals requiring no additional sensing circuits or sensors for detecting rotor speed. A hardware algorithm based on the D-FT method is built, which is convenient to implement to other kind of alternators and systems. This method is verified by prototype simulation and practical tests under the alternator test bench. A six-phase full bridge is trial-manufactured after the driver chip's tape out and performs well under 0–150 A output current and 0–18 000 r/min rotor speed. The test results show that the Verband der Automobilindustrie standard efficiency of the proposed rectifier obtains an 8% improvement compared to that of the conventional diode rectifier.

Optimization of Automotive Bosch-140 Alternator to use as a Generator for Small Wind Turbine

The generator is one of the costly elements of a small wind turbine. This paper developed a suitable low-cost small wind turbine generator, which can be modified to be easily manufactured. The experiment was conducted in two parts, the first part involves monitoring the current, voltage, power, and temperature for the Bosch 140 alternator before re-winding (initial case), and the second part includes monitoring of parameters (current, voltage, power) with modifying the alternator (Bosch 140) by re-winding depending on the results of the JAMG program simulation (last case). The Bosch 140 alternator was modified consistently by reducing the wire diameter to half to double the windings to evaluate the maximum torque. A genetic algorithm was used to optimize the stator’s design optimization to achieve a maximum torque of the magnet. The final result shows a good indication of the modified alternator’s efficiency, where it is increased by about 30% from the initial case, and the generation of voltage started at a low rotation speed. It was observed that the new optimization of claw-pole alternator provides fairly the double torque with at least 16% reduction in rotation speed.

Mathematical-model-based Simulation of an Automotive Alternator Considering the Operation of a Rectifying Circuit

Mathematical-model-based Simulation of an Automotive Alternator Considering the Operation of a Rectifying Circuit

Analysis of the efficiency of an automotive alternator by replacing Mild steel into aluminum as a material for rotor

In real time automotive electrical systems, an alternator is usually used for charging the vehicle. The alternator generates AC voltage which is converted into DC voltage through rectifier of an alternator and this DC voltage helps to charging the vehicle’s battery. The alternator further coupled with the vacuum pump, provides vacuum to the suction line of the vehicle’s braking system. The rotor of the vacuum pump is made of mild steel which weighs high. Hence, it may act as a load to the alternator and reduces its efficiency. In the proposed model, efficiency and performance characteristics of the alternator are improved by reducing the mass of the rotor. Here, the mild steel is replaced by aluminum metal which weighs less. By using this, the mass of the vacuum pump is reduced, due to which the output power of the alternator gets increased. This increase in output power improves the efficiency of an alternator and subsequently the performance of the vehicle’s charging system is improved.

Instrumental monitoring of the load of the automotive alternator during the movement of the vehicle

The charge balance of the vehicle indicates whether the starter battery is being charged while the vehicle is running. For normal operation of the power supply system, the charge balance must remain positive, preventing progressive discharge of the battery. A decisive influence on the balance of electricity is provided by the current output of the alternator, which depends on the rotor speed. The maximum current output of the alternator is described by a current-speed characteristic depending on the technical condition of the alternator. In the process of vehicle movement, the rotor speed and alternator current strength vary over a wide range determined experimentally. The ratio of these parameters is the alternator efficiency coefficient, which can be used to assess the technical condition of the automotive alternator. The productivity of the vehicle’s charge balance is objectively evaluated by the alternator load factor. Further research will be aimed at identifying changes in the charge balance of the vehicle in the event of a malfunction of the automotive alternator and starter battery.

The analyse of the automotive alternator as a generator in Picohydro system: Laboratory experiment test

The aim of this article is to evaluate the feasibility of using an automotive alternator as a Pico water turbine (Picohydro). The automotive alternator system is examined by the pump as a turbine, using water energy in the simulator system to generates the automotive alternator. The simulator equipment that has been made is used to see the performance of the automotive alternator as a generator and recorded a few parameters in the closed-loop system. From this evaluation, the greater the water flow or water pressure that drives the pump as a turbine, the higher the power is produced from the automotive alternator. The Study shows that automotive alternator can be used as a generator and an alternative to generating electricity.

Forecasting of the residual resource of automotive alternators

The urgency of the problem under study is caused by the imperfection of methods for diagnosing automotive alternators, which do not reveal hidden defects, as a result of which the alternator failure is sudden and entails costs due to vehicle downtime in repair. The aim of the study is a method for predicting the residual resource of automotive alternators, built on the results of diagnosing and assessing the operating conditions of an automobile. Analytical expressions describe the dependence of the intensity of an alternator resource on the ambient temperature and operating time, considering its technical condition at the time of diagnosis and the degree of its change under the influence of factors operating conditions on the test run. The theoretical results were confirmed by experimental measurements. The presented results can be used for the full implementation of the resource of automotive alternators in the conditions of road transport enterprises.

Инструментальный контроль зарядного баланса транспортных средств

The instrumental control of the charging balance makes it possible to quickly assess the efficiency and technical condition of the components of the vehicle power supply system. Factors have been developed that allow assessing the technical condition of the automobile alternator (efficiency factor) and its operation efficiency at the current combination of load and engine speed. The main parameters of the power supply system were measured using a four-channel analog data logger. Further research will be aimed at identifying the changes in the charging balance of the vehicle in case of failures of the automotive alternator and accumulator starting battery.

Physical modeling of failures of the automotive alternator

The relevance of the problem of automotive alternator diagnosis is associated with the imperfection of existing methods due to their significant complexity and lack of information. In order the accelerate the process of electrical failures diagnosis, the article considers their physical modelling method, the advantages of which are significant acceleration of the experiment, the possibility of modelling several failures, as well as the establishment of a clear boundary between the serviceable and non-serviceable states of the alternator. Adequately simulating the processes occurring in the alternator, physical modelling is implemented by means of serial or parallel connection to the alternator elements of adjustable active resistance. Experimental data show that the most informative and sensitive to the process of failures development is the temperature increase which can serve as the basis for on-board monitoring system aimed at determining the technical condition of an automotive alternator.

Model of residual resource of automotive alternators

The urgency of the problem under study is caused by the imperfection of methods for diagnosing automotive alternators, which do not reveal hidden defects, as a result of which the alternator failure is sudden and entails costs due to vehicle downtime in repair. The aim of the study is a method for predicting the residual life of automotive alternators, built on the results of diagnosing and assessing the operating conditions of a car, for the first time considering the magnitude of the fluctuation of the output voltage. Analytical expressions describe the dependence of the intensity of an alternator resource on the ambient temperature and operating time, considering its technical condition at the time of diagnosis and the degree of its change under the influence of factors operating conditions on the test run. The theoretical results were confirmed by experimental measurements. The presented results can be used for the full implementation of the life of automotive alternators in the conditions of road transport enterprises.

The design of automotive alternator with high efficiency

A technical solution aimed at increasing the motor life and efficiency of the automotive alternator to an average of 80% is suggested by replacing the permanent magnets on the stator with electromagnetic ones, reducing the number of gaps and their geometric parameters, as well as eliminating brush contacts.

Diagnosing of automotive alternators on thermal state

Since automotive alternators serve as the primary sources of power onboard of vehicles, the online diagnostics of technical conditions thereof is a relevant task. An advantage of temperature as a diagnostic parameter is sensitivity to most faults at the early stage of their development. Physical modeling of faults (stator one-line open fault, stator turn-to-turn short circuit, stator winding phase-to-phase short circuit, circuit opening and short circuit of rectifier diodes) has been done by forced increase (decrease) of electrical resistance between alternator elements. In order to measure alternator temperature, it has been brought to steady thermal state within 20 minutes. It has been found that the alternator temperature in case of faults can increase the rated temperature by 10-30 °С even when the alternator operates without load. An algorithm has been developed to find alternator faults by evaluating the thermal state thereof, which can become a basis of an onboard automatic online diagnosing system of an automotive alternator.