CPT is helping to pioneer several 12-48 volt micro-to-mild hybrid developments.
Controlled Power Technologies will deliver two mild hybrid technical papers at the 80th anniversary of the SAE World Congress in April in Detroit. The first presentation describes a torque assist and kinetic energy recovery system using stop-start technology dubbed SpeedStart. The second paper is on CPT’s turbine gas-energy recovery system known as TIGERS.
Both systems are based on switched reluctance (SR) motor-generator technology developed for a new breed of 48-volt hybrid vehicles. CPT claims multiple O.E. applications are being explored, particularly in Europe for sub-compact and compact vehicles as a relatively inexpensive way to make big gains in fuel economy. (Exhaust Gas Regen and 48-Volt Cars – Next Efficiency Breakthrough?)
“Vehicle electrification and in particular mild hybridization of a conventional powertrain at 48-volts is a rapid growth area for the automotive industry,” says CPT’s chief executive Nick Pascoe. “As a reduced cost concept, it aims to make more intelligent use of electrical energy to achieve the desired reduction in fuel consumption and CO2 emissions. The low voltage approach compared with full hybrid and EV nominal voltages, which are typically in the range of 300 to 600volts, avoids the need for high cost safety features and large battery packs.”
Five German automakers – Audi, BMW, Daimler, Porsche and Volkswagen – have announced their decision to push for the rapid implementation of 48-volt systems. Ford in Europe is also exploring the technology, as is Jaguar and Land Rover. A huge potential market is possible because of pending global CO2 emission targets that are all converging. Simply put, the auto industry has about a decade to achieve another 30% reduction by 2022.
“Sixty volts is defined by the United Nations Economic Commission for Europe (UNECE) regulation R100 as the boundary between low and high voltage in a direct current circuit, and so is a critical point where a step change in system cost can be identified,” says Pascoe. “Further standards such as LV-148 as defined by the Verband der Automobilindustrie (VDA) are providing further structure to the 48-volt nominal voltage approach, which allows high power energy recuperation without exceeding 60 volts.”
The TIGERS system is in use in two research projects supported by the UK’s innovation agency, the Technology Strategy Board (TSB). The HyBoost project consortium partners included CPT, the European Advanced Lead Acid Battery Consortium, Ford, Imperial College London, Ricardo and Valeo; and the Vehicle Integrated Powertrain Energy Recovery project known as VIPER consortium members comprised BP, CPT, Ford, IAV, Imperial College London, Jaguar Land Rover, and the University of Nottingham.
CPT’s SpeedStart and TIGERS technology will also be used in the recently announced Advanced Diesel Electric Powertrain project known as ADEPT. The ADEPT project combines the two technologies, which have been demonstrated individually but not yet as an integrated system, applying the low voltage concept of ‘intelligent electrification’ for the first time to a diesel car – again supported by the TSB. For the ADEPT project, the consortium comprises CPT, the European Advanced Lead Acid Battery Consortium (EALABC), Faurecia Emissions Control Technologies, Ford and the University of Nottingham. Ricardo will handle the management of the project.
Keeping the voltage below the critical 60 volt high voltage safety threshold, the nominal 48 volt technologies to be applied to a Ford Focus aim to “deliver a breakthrough in diesel engine fuel efficiency and CO2 reduction” by demonstrating full hybrid equivalent fuel economy and performance with less than 70g/km CO2 emissions, but at significantly lower cost. The combination of various technologies and slight engine downsizing from the baseline 1.6-liter diesel engine is expected to deliver significant synergy and cost effective benefits without compromising vehicle performance, says CPT.
