Parallel Hybrid: Diesel + Single Electric Motor with Energy Storage

This parallel hybrid propulsion system uses standard Twin Disc electronic controls. It’s best suited for short-trip vessels such as ferries, inland waterway vessels, small/medium passenger vessels, harbor service boats, and pilot boats with sufficient shore time to charge batteries, and for vessels operating in restricted areas or zero-emission zones. Twin Disc technology enables implementation into any standard marine transmission.

Diagram

High Voltage

Data / Command Signals

System Overview

  • Parallel hybrid using diesel and electric power
  • During low-power operation, the e-motor can use excess diesel power to generate electricity
  • In high-demand phases, electric power can boost diesel power
  • Machinery compartments can be located to optimize cargo space or meet class requirements

Marine Transmission

  • Based on standard marine transmission, with same footprint and selection criteria, for worldwide support
  • No trailing pump needed; transmission is lubricated as diesel or e-motor drives it
  • Efficient design minimizes losses

MasterClutch™

  • Permits power generation through PTO/PTI in forward, neutral and reverse
  • Prevents engine back-driving during electric-only operation
  • Supports all features of QuickShift® transmission

PTI Gearbox

  • Drives transmission primary shaft (same as engine) with MasterClutch™ providing dis-connect
  • Allows for standard speed/smaller e-motor through motor speed reduction
  • Offset to propeller shaft enables installation of large motors
  • Reductions from 1.0:1 to 2.5:1
  • Integrated sea water pump cools transmission during electric propulsion
  • PTO available for onboard hydraulics (e.g., steering pump)

Propulsion Controller

  • Twin Disc standard propulsion controller and operator interface

Hybrid Controller

  • Manages power distribution, interfacing with propulsion controller and high voltage equipment

E-Motor

  • Selection based on application characteristics (torque, installation)

Inverter, High Voltage Equipment

  • Controlled and monitored by hybrid controller

Energy Storage & BMS

  • Selection based on application characteristics

Diesel Engine

  • Not supplied by Twin Disc

Marine

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