The GreenGT H2, the first prototype electric/hydrogen competition car, uses Fischer Connectors’ products to solve challenges in extreme sports environments.
Solving new challenges in extreme sports environments requires expertise, innovation, and reliability. To race, for example, a car must comply with FIA rules and safety standards; it needs to be fast on the flat and in the bends; be lightweight; and 100% reliable. When GreenGT, a proactive independent designer and developer of clean and sustainable vehicle propulsion systems, was looking for design solutions for the GreenGT H2, the first prototype electric/hydrogen competition car, it turned to Fischer Connectors to help it meet those levels of performance.
“Fischer Connectors’ innovative products have an excellent track record to perform without constraint in highly demanding environments,” said Jean-François Weber, general manager and head of research and development for GreenGT. “We particularly value the expertise in developing the right connector that meets all our unique technical and environmental requirements, since connectors directly impact the car’s safety, speed, and reliability.”
Facing timing and safety challenges with its innovative hydrogen fuel cell car, GreenGT saw Fischer Connectors as the technical partner that would provide the complete solution, including standard high-quality, reliable connections; complete harnesses; and specially created high-power and -performance push-pull connectors. “In short, we needed to find the connector that could transmit up to 800A and 600V to power the world’s first electric high-performance race car,” said Christophe Schwartz, engineering and program manager for GreenGT H2.
According to Olivier Testaz, a Fischer Connectors’ engineer who specializes in mechanical design, most of the connectors GreenGT wanted to use in the car were close to the supplier’s standard product line, but the Fischer team wanted to ensure they met the car’s specific performance requirements. “We decided to develop some new solutions,” said Thierry Goldhorn, mechanical engineer, “so we took the Fischer UltiMate Series as a starting point because of its built-in ruggedness, and we continued from there.”
Its compactness and resistance to shock and vibration made it an ideal base connector in tight areas around the powertrain, for example. “People wouldn’t believe how many components are packed within such a small space,” added Goldhorn. “In certain places on the chassis, every millimeter counts. We had to be very careful with the design, manufacturing, dimensional, and electric control. We even created special working desks for the cable assembly of the harness. It’s like fitting an A380 cockpit into a glider.”
Since the car must be able to reach 300km per hour in less than 10 seconds, the last thing it needed was heavy connectors and cable assemblies.
Made of aluminum – much lighter than standard brass connectors – the Fischer UltiMate Series fit perfectly in the very light yet resistant structure. The chassis already integrated a lot of carbon fiber composite elements like the 2×160-liter tanks with H2 pressurized at 350 bar, complete bodywork, and a double-hull and crash box shell.
The Fischer Connectors push-pull system was easy to connect and disconnect and offered additional benefits to the GreenGT H2 team when time is critical. With thousands of mating cycles possible and the need to save precious milliseconds during the pit stops, these connectors have a special coating to reduce conductivity and are mechanically coded for safe super-fast blind mating.
“We were looking for reliable high-voltage and high-amperage connectors that are extremely easy to connect and disconnect,” said Weber. “To secure the car when service personnel need to work on it, it is important to disconnect the battery or fuel cell power source. There is no second chance. In these life-threatening conditions, you cannot afford a spark or everything is over. More precisely, people needed to plug or unplug the connectors in less than a second without any risk of harming themselves.”
GreenGT has developed a new high-power fuel cell system that contains neither batteries nor fuel. It provides a linear power of 340kW or 460hp. In parallel, a new lightweight twin-motor powertrain, providing up to 400kW or 540hp, was constructed for the prototype.
“We needed to develop these one-of-a-kind, high-power connectors that deliver up to 275A at 7.0kV DC/5.0kV AC to kick-start the system and the fuel cell, and the receptacles are so close to the pilot that we made them extremely safe to use and access,” said Testaz.
Using hydrogen on the GreenGT H2 racing car improves safety because it is less flammable than petrol. Electric motors improve reliability because they have five times fewer parts than internal combustion engines, and the latest-generation electronic control and telemetry system ensures optimal on-track performance. To cap it all, this high-performing car uses renewable energy and produces no pollutants or emissions of gas, carbon dioxide, or nitrogen oxide.
With standard catalogue references, Fischer Connectors designed new connector solutions for the GreenGT H2 compressor, beam acquisition system, push box, top box tour, light beam, taillights, fog signal, water pump control, 12V power supply, 24V power supply, and much more.
In June 2012, the GreenGT H2 project was selected as an innovative project by the French Automobile Club de l’Ouest (ACO) and invited to participate in the 2013 Le Mans 24 Hours event.
The electrical/hydrogen technology used on the GreenGT H2, conceived as a demonstration model, will be applicable to other vehicles needing high power, trucks, and industrial vehicles.
This case study was provided by Fischer Connectors.