Article

Study of high efficiency DC drive system of ultra-capacitor electric city bus

December 2007

Authors:

The ultra-capacitor electric bus (UCEB) direct currentdrive system uses the permanent magnetic direct current (PMDC) motor with the electrical enhanced magnetism windings as its traction motor, which could regulate the output torque linearly. The main circuit is the current two-quadrant topology. A snubber soft switch based on the characteristic that the ultra-capacitor could be charged fast is designed to heighten the converter's efficiency and reliability, which could be validated by simulations and experiments. Even when the UC voltage varies large-scalely, the converter could insure that the drive system works in its reasonable modes. Nonstandard dual closed loop control reduces the converter's current overshoot and insures that it is comfortable to drive the bus. The high efficiency DC drive system increases the one time traveling mileage when it is used in the limited energy UCEB system.

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Conference Paper

A new magnetic wedge design for enhancing the performance of open-slot electric machines

October 2012

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Article

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August 2006

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Article

Battery Powered Lawn Mower

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Article

Torque Ripple Minimization for Inter-turn Short-circuit Fault Based on Open-winding Five Phase FTFSC...

November 2019 · IEEE Transactions on Vehicular Technology

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Article

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June 2017 · CES Transactions on Electrical Machines and Systems

A novel structure of axial flux stator and rotor dual PMs Vernier machine is presented as an effective option for high torque-density direct-driven applications. The key is to locate PMs on both sides of rotor and stator. With dual PMs, this proposed machine with a novel structure generates an improved torque per armature current at low speed. It is very suitable for direct drive applications ... [Show full abstract] with limited space such as the in-wheel electric vehicle (EV) motors. The theory of the structure with PMs on both sides is analyzed theoretically. The structure and operation principle of machine are introduced and the steady and steady performance of machine is analyzed and verified with time-stepping finite element method (TS-FEM).

Conference Paper

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December 2020

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Conference Paper

Subjective Development of EV Propulsion Noise to Drive Product Differentiation

May 2025

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Chapter

Design of a Wheel-Hub Motor With Air Gap Winding and Simultaneous Utilization of All Magnetic Poles

March 2012

This paper presents a new structure of BLDC motor applied for a wheel-hub motor for an electric vehicle. Today the physical structure of BLDC motors is dominated by a massive stator with salient poles as a framework for the windings. This construction results in high weight and in significant energy losses caused by eddy currents and hysteresis losses in the stator material. Furthermore, a huge ... [Show full abstract] amount of conductor material is needed, mostly with limited cross-section areas, so that resistive losses occur. In this paper a new approach to a permanent excited electrical motor is presented that allows for stator constructions with reduced weight, size, resistive and magnetic losses in combination with a very compact and high efficient air gap winding that allows for simultaneous utilization of all permanent magnets to generate very high torque. The design of a wheel-hub motor useful to drive a 4WD electric vehicle is presented.

Conference Paper

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September 2011

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Conference Paper

Drive motor designs for electric motorcycles

September 2012

This paper addresses the design of motors for electric motorcycle racing. These tend to be high torque-dense brushless permanent-magnet machines (either DC or AC) operating over a very wide speed range with an extended maximum power range above base speed. The thermal design and operation are key to their successful utilization and this is a major focus of this paper. The motors can operate at ... [Show full abstract] very high current density for a short time during acceleration.

Article

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May 2007

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Article

Development of a Consequent-Pole-PM-type Axial-Gap Motor with DC Field Winding

May 2021 · IEEE Transactions on Industry Applications

Permanent magnet synchronous motors (PMSMs) for electric vehicles should meet three criteria: high maximum torque, high efficiency at low torque, and constant output in a wide speed range. However, meeting these criteria has come with a trade-off in terms of the magnitude of the field magnetic flux. We propose a consequent-pole-PM-type axial-gap motor with ferrite PMs and field windings, which ... [Show full abstract] has structure variable field magnetic flux. In order to examine the operational characteristics of the proposed motor, we produced and tested a prototype. Experimental results show that the proposed structure meets all of the three criteria above.