New U.S. government auto safety regulations provide a new incentive to Technologies M4 Inc. (TM4) to advance the development of its revolutionary electric drive system for a wide range of electric-powered cars and light trucks, the company’s president said here today.
David Johnston said recently-revised brake test requirements for electric cars create a more favourable environment for the development of the TM4 drive system for various vehicles including four-wheel drive and sport utilities. He spoke to news media at the 17th International Electric Vehicle Symposium in Montreal.
The innovative TM4 drive system integrates a high-efficiency electric motor with its power and control electronics into a system housed in the vehicle’s wheels. It can be used with all types of electric, fuel cell and hybrid power systems and offers a variety of advantages for vehicle design flexibility and improved control and handling.
The U.S. National Highway Traffic Safety Administration (NHTSA) amended its brake test requirements for electric vehicles last February, eliminating an obstacle to the application of regenerative braking systems (RBS). “Under the new regulations, we can proceed to develop very competitive and realistic applications of our cutting-edge electric motor wheel system as alternatives to conventional drive trains,” Johnston said.
The new NHTSA standard allows use of an electric vehicle’s RBS during certain tests if it remains functional when electric power to the propulsion motors is switched off. RBS extends an electric vehicle’s driving range by applying its kinetic energy to recharge batteries as the vehicle is being decelerated. The RBS can provide an important component of a vehicle’s total braking force requirements.
The previous standard required electric vehicle brakes to meet certain tests with the RBS system inoperative. To meet the test requirements without using RBS, the TM4 system would require modifications that would compromise applications such as 4 X 4’s and SUV’s.
The TM4 system combines both RBS and hydraulic brake systems with approximately equal braking force capabilities, Johnston explained. In operation, the RBS provides the primary braking force, and the hydraulic system is activated when the required braking force approaches the maximum capacity of the RBS.
The braking force of the TM4 RBS is not dependent on the state of charge of the propulsion batteries, he said. Unlike most other RBS, TM4’s RBS can function if the batteries are fully charged with the use of a remote energy dissipator, and if the motors are not powered.
NHTSA said the revised standard will maintain safety benefits while improving the ability of the standards to take full advantage of the unique design features of electric vehicles.
Founded in 1998 by Hydro-Quebec to commercialize electric power technology which has been developed since 1991, Technologies M4 Inc. is a “value-added” company offering custom adaptations of its core product base in the specialty market. Its mission is to develop, design and supply electric power generation, conversion and control systems to the transportation, energy, telecommunications and automation industries for improved energy efficiency and safety and environmental benefits, based on highly integrated power and control technologies.