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Magnetorheological (MR) fluid dampers are the most promising devices for practical vibration control applications because they have many advantages such as mechanical simplicity, high dynamic range, low power requirements, large force capacity and robustness. This paper aims to study the dynamical behavior of a linear MR fluid damper through experiments. Also, an efficient and simple model is developed to identify the damping force as a function of the damper velocity, acceleration and applied voltage to the magnetic coil, without using any complicated mathematical or differential equations, which will be very useful for large and complicated applications. The identified parameters of the MR damper are obtained using trial-and-error methodology. The validation is done using the dynamical behaviour of MR damper for both experimentation and simulation, by solving the modified Bouc-Wen (M B-W) model that can predict the dynamical behavior of MR dampers accurately.

The estimation of vehicle battery performance is typically addressed by testing the battery under specific operation conditions by using a model to represent the test results. Approaches for representing test results range from simple statistical models to neural networks to complex, physics-based models. Basing the model on test data could be problematical when testing becomes impractical with many years life time tests. So, real time estimation of battery performance, an important problem in automotive applications, falls into this area. In vehicles it is important to know the state of charge of the batteries in order to prevent vehicle stranding and to ensure that the full range of the vehicle operation is exploited. In this paper, several battery models have studied including analytical, electrical circuits, stochastic and electro-chemical models. Valve Regulated Lead Acid “VRLA” battery has been modelled using electric circuit technique.

The DC power supply is ingredient part in the automotive industries as it has been used as a DC power supplies for a wide range of loads. Meanwhile, it is mandatory for battery charging. These types however, causes many problems such as poor power factor, high input current harmonics distortion and uncontrolled DC voltage. In this paper, an improved input power factor correction that uses a combined control system consists of two nested loops with a feedback of the DC voltage and input current as long as a feed forward from the output power. The system has been analyzed, modeled, simulated and experimentally verified. The novel feature of the proposed control scheme resides in fact that it is not only achieve nearly unity power factor with minimum input current total harmonics distortion only but it also introduce superior performance in DC voltage transient conditions.

In recent years, the development of environmental friendly vehicles, such as electric vehicles and fuel cell vehicles, has further accelerated. Hybrid vehicles with regards to practical application which employ a combination of gasoline engine and electric motor remain one step ahead of the other technologies. On the other hand, as for noise and vibration (NV) phenomena, hybrid vehicles have many different features from those of conventional vehicle. Firstly high frequency noise is generated by the hybrid units, such as motor/generator and power control unit. Secondly low to middle frequency NV phenomenon tends to be worse. However, this paper describes the noise characteristics for HV induction electric motor, where its noise comprises three types namely: electromagnetic, aerodynamic and mechanical. Moreover, the influences of the cooling fans' blades number on both motor aerodynamic and total noise are presented.

Reduction of alternator noise has become an increasingly important task in automotive industry as requirements for passenger compartment comfort increase, and other components such as the engine, exhaust system, etc. are made quieter. However, the aim of this study is to identify the noise sources of a numbers of alternator bands and to develop design guidelines to reduce the overall noise levels sacrificing the specified performance. With these guidelines, design engineers can reduce alternator noise effectively. To identify mechanical, aerodynamic and electromagnetic noise generation mechanisms, the alternator was reconfigured in many different ways, so as to separate each individual noise source. Noise generated by each configuration running at different speeds was measured, and its characteristics were analyzed. A special test stand was designed and fabricated, and tests were conducted in the automotive laboratory.

The three-phase induction motor is the trend in electric & hybrid vehicles. The Voltage Source Inverter (VSI) which is driver and speed controller of the motor suffers from many problems. Resonant DC link is showing tremendous promise for next generation VSI used in adjustable speed AC machine drives. Although the resonant dc link inverter has many advantages but it has two major problems. The first problem is the resonant link voltage overshoot. The second one is the resonant link voltage zero-crossing failure. This paper presents an initial current optimization technique to solve the resonant voltage overshoot and zero crossing failure for smooth inverter and in turn vehicle operation, minimum weight & cooling requirements, low audible noise and improved efficiency. The resonant circuit has been mathematically analyzed to establish the proposed technique. A group of performance curves which allow the designer getting the optimum initial current at different resonant tank parameters.