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Single tooth winding Interior Permanent Magnet (IPM) motors are widely used for Hybrid Electric Vehicles (HEV) and Fuel Cell Electric Vehicles (FCEV). Because of its structure, however, the higher spatial harmonic may appear and induces strong nonlinear characteristics. The control system therefore requires high response and robustness control. In this paper, we introduce a systematic method to design a gain-scheduled H∞ controller with high level of robustness for IPM motor control system. It is generally adopted that the designer makes model data first before designing a controller. On the other hand, this paper presents the method to treat uncertain parametric model and controller synthesis simultaneously. Experimental result is demonstrated and shows that our method achieves superior performance to the existing methods.

The performances of some vehicle control systems are influenced by changes in the weight of the vehicle. In these systems, it is important to be able to estimate the weight without the need for special sensors. When we use physical models to do this, we have to provide estimates for two or more unknown parameters. In addition, since such a method is influenced by disturbances in the measured signals, it is difficult to maintain an acceptable level of accuracy. So, after analyzing the physical phenomena, we developed a new method that eliminates the influence of the disturbances from the measured signals and constructed an estimation system that has a minimum number of unknown parameters that was capable of providing a more accurate estimate of a vehicle weight. This method was applied to the braking force control of an automatic transmission and its efficacy was verified.

Electric Active Stabilizer (EAS) system, that is capable of having a good balance between roll angle control and comfortable driving, has been developed. The EAS system can automatically control a roll angle by using the DC motor actuator installed in the center of a stabilizer bar. The actuator consists of a small brushless DC motor and a compact gear set. In order to improve vehicle drivability and to secure robustness against ambient temperature and power supply voltage fluctuation, we found that the motor rotation control was critical. In order to improve the motor rotation control, an actuator structure was optimized and H∞ control algorithm was introduced to have an excellent response and stability. As a result, the EAS system with high efficiency and reliable has been achieved. In this paper, the results are explained with a comparison between simulation results and experimental results.

Switched Reluctance Motor (SRM) mainly has two advantageous characteristics such as no magnet and simple construction. These characteristics contribute lower cost and higher reliability compared with other motor systems such as brushless permanent magnet motors or induction motors. However, SRM has disadvantages that are its torque ripple and acoustic noise in particularly. Moreover, the resonance frequency mode of a motor system is excited by torque ripple, and drive train vibration is caused. These noise and vibration should be suppressed when the SRM is applied to a traction system for passenger electric vehicle since these characteristics affect vehicle quietness and drivability. In this paper, we describe an approach to suppress drive train vibration and acoustic noise.

Into the early-part of the next century, automotive emission standards are becoming stricter around the world. The electrically-heated catalyst (EHC) is well known as an effective technology for the reduction of cold-start hydrocarbon emissions without a significant increase in back pressure. Our extruded, alternator powered EHC (APEHC) manufactured with a unique canning method and equipped with a reliable, water proof electrode has demonstrated excellent durability and reliability, as stated in our previous SAE paper (#960340). The APEHC system discussed in this paper has achieved the Ultra-Low-Emission Vehicle (ULEV) standards, after 100,000 miles of fleet testing, without any failure. This is the final milestone in addressing the EHC as a realistic-production technology for ULEV. With the ability to meet ULEV/Stage III emission targets without a significant increase in back pressure, the EHC will be applied to an especially high performance vehicle with a large displacement engine.

An electrically heated catalyst (EHC) and an electric pump driven secondary air supply were employed to heat and energize the catalyst immediately after starting the engine. This measure made it possible for a high performance in-line four-cylinder engine with an exhaust system layout of 4-2-1 to meet the Ultra Low Emissions Vehicle (ULEV) category of the Californian Air Resource Board (CARB).