Voith Turbo will begin production of its DIWAhybrid drive system for transit buses in North America this month. (Earlier post.) Over the last 18 months, Voith Turbo has fine-tuned and tested DIWAhybrid to better understand how the drive system can best be utilized in municipal transit routes in North America. In recent multi-day real test runs, the DIWAhybrid drive system gained an average of 16% efficiency.
The DIWAhybrid is based on Voith’s DIWA heavy-duty transmission, which has more than 100,000 units installed worldwide. The parallel system operates on a power split principle. The asynchronous motor/generator in the system delivers constant power of 85 kW, with maximum power of 150 kW. During braking, the motor works as a generator and optimally complements the DIWA secondary retarder.
The DIWAhybrid system uses a 600V bank of ultracapacitors, as opposed to a traditional battery, which will require less lifetime maintenance over its competitors. A typical battery will only last 6 years, whereas the ultracaps can last beyond 12 years, Voith says.
Voith Turbo will use Maxwell Technologies’ Ultra capacitors in the production of DIWAhybrid, expanding on its partnership. Maxwell Technologies is supplying capacitors for Voith’s Hybrid Power-Train Development Center, which is based near San Diego, CA. The Hybrid Power-Train Development Center will build and expand on Voith Turbo’s hybrid bus technologies.
Voith Turbo, the specialist for hydrodynamic drive, coupling and braking systems for road, rail and industrial applications, as well as for ship propulsion systems, is a Group Division of Voith GmbH.