Optimum Design of TFLM with Constraint to Maximize Thrust Force, Minimize Detent Force for Weight Reduction Using Characteristic Function
This paper presents optimum design of transverse flux linear motor(TFLM) for household electric refrigerator. We use a characteristic function, table of orthogonal array and three-dimensional equivalent magnetic circuit network (EMCN) method to explain correlations between the objective function and design variables, maximize thrust force and minimize detent force for weight reduction. This paper procedure is validated by the comparison between experimental and calculation results
Lightweight design of an in-wheel motor using the hybrid optimization method
An increase in the unsprung mass is a critical issue for an electric vehicle driven by an in-wheel motor. The mass increase will cause the ride quality and comfort to deteriorate. To decrease the unsprung mass, a hybrid lightweight design method including size optimization and topology optimization is employed for the in-wheel motor. The two optimizations are carried out in sequence. First, the finite element method, the response surface method and the particle swarm optimization algorithm are employed in the size optimization design of the in-wheel motor. After this step, the mass of the in-wheel motor is reduced to 2.7448 kg, while its rated torque and losses are almost unchanged. Second, according to the above optimization results, topology optimization using the method of variable density is employed for the supporting frame of the stator of the in-wheel motor, which is the non-magnetic area. The material which is grade 45 steel is analysed. The optimization results show that, after optimization and treatment, the mass of the supporting frame is reduced to 1.069 kg, i.e. 63.11% lighter than before. Then, structural strength verification is carried out. Considering the above two optimization steps synthetically, the total mass of the in-wheel motor with a grade 45 steel supporting frame is reduced by 3.5547 kg, which means that it is 13.623% lighter than the original structure. Calculation of the transient torque and losses show that, after optimization, the total loss is reduced by 1.87%, and the torque by only 1.8%. Therefore, the hybrid optimization method studied in this paper works well for the lightweight design of an in-wheel motor.
Integrated Energy Transducer Drive for Hybrid Electric Vehicles
i This thesis deals with a novel concept for a complete hybrid electric vehicle drive. The major contributions of the thesis are the patented integrated energy transducer drive for hybrid electric vehicles, its equations and control, besides design and construction of the integrated energy transducer. The increasing number of combustion driven vehicles and power generation based on burning fossil fuel e.g. oil, gas and coal, have lead to severe air pollutions in some areas and the CO2emissions contribute to a possible global warming. These problems have forced legislators to legislate for cleaner and more environmental friendly fuels and vehicles. One possibility to fulfil these legislations, is hybrid electric vehicles. These vehicles have generally less toxic emissions and higher fuel efficiency, than conventional combustion driven vehicles. During the last decades, the main hybrid electric vehicle drives have been series and parallel hybrid electric drives. In the last 5-7 years special combinations of these drives have also been presented. The novel integrated energy transducer drive for hybrid electric vehicles, is based on a different drive concept than the conventional series or parallel drives. The main components in the drive are an integrated energy transducer (IET), an inverter, a battery, a continuously variable transmission and an internal combustion engine (ICE). The integrated energy transducer drive enables the internal combustion engine (ICE) to operate with a constant torque and rotational speed, which reduces the emissions and increases the fuel efficiency. The number of components are few and the rated power of the electric components is the same as that of the battery. Known hybrid electric vehicle drives are presented together with the important components of the drives. The IET-drive is presented with all its operating modes. Component requirements and the design procedure of the transmission components are also given. A theoretical investigation is conducted on possible electric machine topologies of an IET, followed by a theoretical design of an IET. A constructed permanent magnet IET-prototype is presented and investigated. Measurements are compared with theoretically calculated values. The IET is a double rotor machine, which means that both the rotor and the stator, containing a three-phase winding, are rotating. The dynamic equations of the IET-drive are derived. In hybrid mode, the IET-drive requires special control algorithms, since the system is a non-minimum-phase system. The control of a complete integrated energy transducer drive is presented. Dynamic simulations are conducted on the drive with the FTP-75 drive cycle. The simulation results are investigated and the simulations verify that the ICE can operate at a constant arbitrarily torque and rotational speed, independent of the road load. Furthermore, dynamic test results of the IET-prototype are investigated and presented with its control. Drives of electric and hybrid electric vehicles produce different sounds, compared to conventional vehicles, for the surroundings, but mostly for the driver. Transmission noise could therefore be recognised in a hybrid electric vehicle. Therefore, it is vital that the drive of a hybrid electric vehicle is silent and does not create unnecessary noise. One noise which might occur in the transmission of a hybrid or electric vehicle, originates from cogging in