German Company Unveils 48-Volt Electric Boat Motor
Volabo, a company formed in Munich in 2013, recently introduced and tested a 48-volt electric boat motor, the ISCAD V50. The motor has a peak power rating of 80kW (96 hp) and nominal power of 50kW (65 hp) and the manufacturer says it will go into production with estimated delivery date of December this year.
Polar Opposites
The key to the motor is a technology called Intelligent Stator Cage Drive (ISCAD). It creates what Volabo calls a “virtual gearbox” that changes the speed of magnetic poles in the stator cage. The stator uses aluminum bars arranged like a cage instead of the heavy copper windings used in many electric motors. The bars are paired to create magnetic poles. The fewer the paired poles, the faster the motor can turn. This results in a change in the motor’s torque.
Motors with permanent magnets or wound coils work on a pre-determined number of pairings, meaning there is one optimum rating for rpm and torque. ISCAD lets Volabo adjust to the type of load required and provide the best speed and torque for the task. The other essential part of the system, aside from the aluminum bars and the pole pairings, is an electronics system that decides when the pairings should be changed.
Another advantage of the ISCAD V50 is that it was developed as a low-voltage motor. The wiring and clamping technology is much simpler and 48 Volts is also at the power level where technicians working on the installation do not require any special training. Until now, high performance has meant high voltages of up to 800 volts.
The Partnership
To demonstrate the ISCAD V50, Volabo partnered with another German company, Elektroboat on a 22’ (6.7 m) center console with a straight shaft drive propulsion system. Volabo says this is the appropriate size for a powerboat, while a sailboat could be as large as 55’ (16.76 m) and 17 tons (15,422.4 kg) displacement.
The boat made its debut at the Tulin Boat Show in Austria in early March.
The Magic Number
That 50kW of power is important, because many electric boat motors typically start to jump to voltages above 48 volts at the 20 or 25 kW power level.
Adrian Patzak, one of the co-founders of Volabo, said, “We didn’t want to offer another 48-volt drive for small outputs. We wanted to start right away where it is currently only possible to electrify a boat with high-voltage systems.” Patzak and the other co-founder, Florian Bachheibl, have been developing the motor since the ISCAD concept was introduced to them by Professor Dieter Gerling, Dr-Ing when they were students at Munich’s University of Federal Defense.
The overall size of the ISCAD V50 is small, 45 kg/95 lbs and 10.5” (26.55 cm) long with a diameter of 10” (25.40 cm). The company says a smaller motor that measures 9.5” x 10” (24 cm x 25 cm) is under development. To make the engine more adaptable to horizontal or vertical installation, ISCAD V50 has a reinforced end shield so it can therefore be used as an outboard, saildrive/pod, inboard shaft drive or Z-drive/stern drive.
Fifth Generation
The production model of the ISCAD V50 is the fifth generation of the motor. The engine has received the German Mobility Award 2018 from the Federal Ministry of Transport, the Create the Future Design Award 2018 from Tech Briefs and the Handelsblatt Energy Award 2018. The company received its first patent in April 2014 and has since been granted seven more and has submitted 45 applications worldwide.
In 2016, Volabo (which means ‘fly’ in Latin) was incorporated. Later that year it delivered Prototype #2 followed by #3 in September of 2017 – a 100kW stator cage motor powerful and compact enough to be tested in a VW Touran a year later.
The fourth generation of the motor, the V50 ISCAD, was installed in the Elektroboat. The V50 was unveiled in late January of this year along with the announcement of ‘a seven-digit (Euros) Series A financing round’ from the Hechinger group of companies. Hechinger is in the automotive and electronics sectors and the investment is pegged for boat and marine Volabo product development.