Podded Propulsion

Overview

Electrification’s SEAJET* podded propulsion system is the ideal choice of electric propulsion for applications where maneuverability, efficiency or space constraints are very important. The electric motor is housed in the hull-mounted pod under the ship and directly connected to the propeller, freeing up cargo and operational space in the ship. Through system efficiency, total fuel consumption and exhaust emissions are reduced.

INCREASED EFFICIENCY

The benefits of SEAJET* for owners and operators include increased propulsion system efficiency, reduced total installed power generation, reduced total fuel consumption and exhaust emissions, reduced noise and vibration levels and improved maneuverability. For shipyards, the benefits include flexibility in the machinery arrangement, a simplified machinery installation with fewer components, a simplified hull form and reduced installation time and cost.

Range and SEAJET* pod technology

Electrification’s pods have demonstrated their robustness across naval, merchant, and offshore applications. The newly updated technology and variants are gaining traction with owners building Arctic tonnage and needing rugged, ice-class capability, and will play a major role in this growing industry. The ice-class range of the SEAJET* system is a joint technology development with AETC Sapphire. Systems are available for ice-going vessels up to icebreaker 7 ice notation with a power range from 7.5MW to 15MW†. The technology uses a pyramidal strength philosophy to withstand extreme loads on the propeller blades, steering system, and propulsion module.

Ice class specialists, from ice breaking to Arctic transport

The SEAJET* pods are selected for a series of LNG carriers being built for Rosneft’s Arctic LNG program. Sapphire Pod Manufacturing Plant, a joint venture between Electrification and Rosneft Oil Company, will supply the electric power and propulsion systems for five new ice class LNG carriers. The technology package provides the ice-breaking and ice-maneuvering capabilities needed to traverse the increasingly active Northern Sea Route between Europe and Asia, bound by ice for most of the year. Each integrated electric drive power and propulsion system includes three 15MW† Arc 7 SEAJET* ice class podded propulsion systems, generators, HV switchboards, propulsion transformers and MV7000 propulsion convertors. SEAJET* has also been chosen for a series of 100-metre ice breaker supply vessels under construction in Russia for Rosneft.

In February 2021, Electrification was added as a Strategic Partner to Chantier Davie’s Polar Icebreaker program. Chantier Davie, Electrification, Vard and Serco form a center of excellence for polar technologies and Arctic expertise in Quebec’s maritime cluster where they will focus on the replacement of Canada’s ageing icebreaker fleet. GE has already delivered its Integrated Full Electrical Power and Propulsion System for a series of the Royal Canadian Navy’s Arctic and Offshore Patrol Ships (AOPS), with the last two ships in the eight-ship series scheduled for delivery to the Canadian Coast Guard. The Canadian Coast Guard are considering pods for their future polar class icebreakers.

MODULAR DESIGN

Description

The pod systems are designed to be modular and include an inboard and auxiliary equipment module, a steering module, and a propulsion module. This modular approach provides for cost-effective standardization of inboard components across the Electrification product range and improved ability to adapt the pods to the hull of each individual project

Dry dock availability

The pod is installed under the hull and can be accessed from inside the ship to allow for inspection and all regular maintenance without the need to schedule dry dock availability. The safe handling of braking, locking, and turning can be achieved without the need for manual access into the pod.

Anti-pollution system

Additionally, a pressurized air system prevents any air-contamination or condensation in the pod. An anti-pollution seal system ensures environmentally safe operation and long service life, with the advanced bearing system capable of operating reliably without continuous operation of an external lubrication circuit

High maneuverability

The pod’s electrical steering system provides high thrust and steering dynamics at 360° which results in high maneuverability and station keeping performance for both dynamically positioned (DP) and non-DP vessels. The special design of the steering module has simplified the pod hull’s interface with the ship

Power and simplicity of Electrification’s induction motors

SEAJET* pods equipped with Electrification’s advanced induction motors draw on decades of proven propulsion technologies and empower shipowners to improve the performance of their vessels and to also reduce emissions to enable more sustainable operations. The simplicity of the system increases the reliability and the availability of the motor and increases efficiency and power usage. The noise and vibration behavior of our induction propulsion motors is excellent and has been proven on many naval and scientific vessels

The auxiliaries are compact to facilitate integration in the pod room, using a smaller induction motor with a pressurized bilateral cooling system which limits any differential thermal effects. The SEAJET* pod induction motor compact rotor design eliminates any possible collision of the rotor with the stator even under the worst shock conditions that can be encountered, such as on an ice class vessel. The larger air gap also contributes to the ability of the motors to achieve very low structure borne noise levels.

The ability of the highly-efficient MV7000 PWM drive to operate at very low frequency allows the motor pole number to be optimized. SEAJET* pods are also compatible with transformer-less solutions, hybrid variable AC networks and energy storage DC/DC converters. For multiple drive applications, a common DC link fed by a single active front end can reduce overall equipment cost and footprint.