Robert Dean King

Hybrid electric transit bus pollutes less, conserves fuel

This true low-floor bus prototype has the performance of a conventional diesel-powered vehicle with hardly any fumes. The authors discuss the design of this series hybrid bus, and in particular the propulsion system. Four independent AC drives, one integrated into each driven wheel, are used. They are powered by a battery assisted auxiliary power unit consisting of a downsized heat engine coupled to an alternator. The authors describe the tests carried out on this bus. >

DOE HYBRID TEST VEHICLE--RESULTS OF FUEL ECONOMY EMISSIONS AND ENGINEERING CHARACTERIZATION TESTING

A parallel-configuration, microprocessorcontrolled Hybrid Test Vehicle (HTV) has been designed and developed by the General Electric Company for the U. S. Department of Energy. It has successfully demonstrated on/off internal combustion engine (ICE) operation and dual (electric and ICE) power-system blending. Results of testing the HTV at the Jet Propulsion Laboratory show that the HTV is capable of saving significant amounts of petroleum while maintaining standard ICE vehicle performance. The HTV program operational experience has shown the need for design simplification and special battery considerations in future hybrid vehicles.

A Microcomputer-Controlled Powertrain for a Hybrid Vehicle

The design and testing of a microcomputer-controlled powertrain for a hybrid (heat engine/electric) vehicle are described in this paper. The detailed control strategy used and its software implementation on the Intel 8086 microcomputer are discussed. The powertrain is made up of an electric motor, gasoline engine, automatic transmission with the torque converter removed, engine and electric motor clutches, and Hy-Vo transfer chains. The drive system has been installed in vehicles and tested on a chassis dynamometer. Test results show smooth shifting of the transmission and sequencing of the clutches in the different hybrid operating modes. The overall performance of the hybrid car is good, and driveability is comparable to a conventional automobile.

ETX-II 70 Hp MCT inverter electric drive system performance tests

This paper describes a high-performance ac electric drive system, consisting of a high-efficiency (95 to 97 percent) 70-hp interior permanent magnet (IPM) synchronous motor, an advanced MOS-Controlled Thyristor (MCT)-based three-phase inverter, and microcomputer-based inverter/motor controller. It presents performance and system efficiency test results of the 3-phase MCT inverter and IPM motor (mounted in the test transaxle and coupled to the dynamometer). MCT module tests were run at 204-V, 250-V, and 270-V dc link voltages, while drive system tests were run over the torque-speed plane to characterize the electric drive system for 150-V and 200-V dc link voltages. Test results, include here, show the ETX-II MCT inverter-based electric drive system has 2-3 percentage points higher efficiency than the corresponding ETX-II Darlington inverter-based electric drive, over a significant portion of the torque-speed plane.