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Submarines are the vessels which depend most upon the complete reliability and operational readiness of their propulsion motors. A drive system that operates efficiently with very low signatures is essential for long dives and makes the boat harder to detect. With the Permasyn drive motor for submarines, excitation is achieved with the aid of permanent magnets allowing it to work without addtional electrical excitation. Although it is smaller and more lightweight than conventional propulsion solutions, it achieves much better efficiency at extremely low signatures.

Supremely compact and light

The Permasyn propulsion motor is a highly-efficient lightweight unit with an ultra-compact design. Its redundancy gives maximum fail-safe performance. It is customised to submarine applications due to its low heat emission, space-saving design and modules which are readily accessible for maintenance.

The electronic speed control eliminates torque-free range changes, switching noise and high current peaks. The high available torque across the entire speed range means that larger and more efficient propellers can be utilised.

Efficient technology for maximum performance and flexibility

As the Permasyn propulsion motor is excited by means of permanent magnets it requires no exciter power. Moreover, the poles and coils are designed for minimal power loss. Losses and noise generation are further minimised by optimising the power curve and pulse frequency and controlling the phase which is dependent on speed.

Thanks to the integration of an IGBT converter Permasyn has a short and compact design and so is perfectly suited to the tight space constraints on board submarines. Electromagnetic shielding reduces cost compared to conventional systems with fragmented drive systems.

A part of the propulsion system is already integrated into the Permasyn drive. Switching between different drive speed ranges is not necessary - with the aid of electronic speed regulation, torque-free shift intervals, switching noise and high current peaks are a thing of the past. The Permasyn achieves higher torque at low speed compared to conventional drive solutions and is therefore able to drive larger propellers with much greater efficiency.

Low signatures making the boat harder to detect

Being compact and easy to shield and with its low noise and low vibration drive technology, the Permasyn achieves very low signatures. Therefore an active noise compensation system is usually not requisite, but can be allotted. Minimal noise and electromagnetic signatures together with nominal heat emission make boat detection much more difficult.