Search Results

Postal delivery vehicles provide an excellent opportunity for using electric propulsion, since the number of miles driven daily on the delivery route is established and consistent. The vehicles also return nightly to a central depot so charging infrastructure is not an issue as long as the vehicles have sufficient charge to complete the routes. The United States Postal Service has evaluated electric vehicles for postal carrier route vehicles several times. The latest trial concluded in 2001. During the test of electric postal carrier route vehicles, the range was usually adequate for the delivery route; however there were a few instances of vehicles having to be retrieved because they had exhausted their batteries. This paper describes a series hybrid electric vehicle that addresses range issues with an on-board internal combustion engine powered generator to extend vehicle range.

In the report, a new version of machine with DC stator excitation is discussed. A brushless one phase electrical machine has a very simple design. Rotor has no windings. In generator mode operation, stator has one winding for DC stator excitation and one output winding. In motor mode operation, there is only one sensor of rotor position and one phase H-bridge inverter. One phase machine is symmetrical. Like in dc machines, it is possible to realize here: shunt, series, and separate excitation. In motor mode, the speed control is possible by vary armature (output winding) voltage, varying current excitation, and varying resistance in armature circuit. Simplicity construction and flexibility control opportunities can find for this machine wide application in vehicles. Motor, with series excitation, leads a torque-speed characteristic that is useful for transport power circuit applications. One phase machine is the basic for design of two and three phase machines.