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This paper indicates the market for a van-type electric vehicle, provides the physical description, and presents the electrical principle of operation of a frequency modulated and pulsewidth modulated power system applied to a 27-kW three-phase squirrelcage age induction motor. This ac drive system, which represents the third generation in design, has been placed in a Dodge B-300 high production van of 2700 kg gross vehicle weight. The electrical energy is stored in 24 6-V 220-Ah batteries providing 144 V. Design speeds of the electronics for the vehicle are up to 90 km/h. Computer developed power factor and efficiency curves are given for the motor for the entire range of operating speeds. Electrical charge in the batteries may be replaced either by quick interchange of batteries a or through utilization of a 12-kg on-board charger with an electrical demand of 6 kW from a 220-V single-phase main. Finally, the paper discusses the economics of the ac drive LinearVan.

The paper presents a new control strategy and design for auxiliary energy source (AES) used in battery hybrid electric vehicle (BHEV) based on the acceleration power. The control strategy takes actual speed and acceleration of the vehicle and system losses into account for regulating the energy and power supply to the propulsion load. The design of AES and its dynamic control design are demonstrated. Cascade control is availed in this work in order to control the terminal voltage and current of supercapacitors (SCs). The benefits of AES in which recapture of regenerative braking energy are examined by the numerical simulation and verified by a small scale experiment. The comparison of energy consumption and DC bus voltage regulation between pure battery and battery with supercapacitors (BSCs) propulsion system declares the theoretical results and confirms the benefits of the proposed method.

During the past ten years the Army has invested a sizable effort into new systems configurations and development programs to improve ground vehicle mobility. United States Army Mobility Equipment Research and Development Center (USAMERDC), Fort Belvoir, Va., has been particularly interested in an improved vehicle mobility for off-highway vehicles, amphibians, and engineer equipment through electrical propulsion. Such drive systems incorporating individual wheel controls provide improved mobility over all types of terrain, simplified supply logistics, and permit a more functional vehicle design and construction. Past experience in industry and in the government has shown that the dc motor propulsion drive is inherently simple to install and to maintain. The dc motor is somewhat heavier than comparable ac motors due to motor speed limitations; however, the dc machine, particularly the series field motor, requires relatively simple power controls since the power is processed by the motor's own commutator. Commercial dc traction motors have an inherent high-torque starting characteristic which is mandatory for engineer-type vehicle propulsion applications. In the midspeed range however, presently available dc motor propulsion drives under consideration for the Anny have unsatisfactory acceleration performance when compared to conventional mechanical drive systems comprised of a spark or compression ignition engine and a multispeed transmission. In this context, the paper discusses this Center's experimental solid-state controller and the method employed to improve the acceleration or peak power propulsion profile of an electric vehicle drive using dc series field motors.