marine diesel generator set for main or standby power supply

Marine diesel generator set is a kind of equipment that utilizes diesel engine as the prime mover to drive generator to produce electricity, which is widely used in all kinds of ships, including cargo ships, passenger ships, fishing boats, oil tankers, engineering ships, warships and so on. Its role is to provide reliable power for all kinds of equipment on the ship (navigation, communication, lighting, living facilities, etc.) and the power system.

Marine Diesel Generator Set Components

Diesel Engine (Main Power Unit):
- Provides mechanical energy for the generator.
- Four-stroke or two-stroke, marine-adapted design.
- Water-cooled (closed-loop fresh water or direct seawater cooling).
- Equipped with exhaust gas turbocharging to improve fuel efficiency.
Generator:
- Converts mechanical energy into electrical energy.
- Typically three-phase synchronous alternator.
- Anti-salt spray, moisture, and corrosion-resistant design.
- Common voltages: 400V, 440V, 690V; Frequency: 50Hz or 60Hz.
Control System:
- Monitors and automates generator operation.
- Control panel displays voltage, current, frequency, oil pressure, temperature, etc.
- Automatic protection: low oil pressure, high water temp, overspeed, overload, short circuit, etc.
Fuel System:
- Supplies diesel fuel.
- Includes fuel tank, pump, filters, high-pressure injection system.
- High-efficiency filters prevent fuel impurities from damaging the engine.
Cooling System:
- Prevents engine overheating.
- Closed fresh water cycle or direct seawater cooling.
- Large ships use heat exchangers to reduce water consumption.
Lubrication System:
- Reduces engine wear, extends service life.
- Includes oil tank, pump, cooler, filter.
- Automatic alarms for oil pressure and temperature.
Exhaust System:
- Discharges diesel combustion exhaust gases.
- High-temp resistant materials; muffler reduces noise.
- Exhaust treatment (e.g., SCR) reduces NOx emissions for environmental compliance.
Vibration Damping Device:
- Reduces vibration and noise during operation.
- Elastic connections and shock-absorbing pads ensure smooth running.

Working Principle

Combustion Provides Mechanical Energy: The diesel engine completes intake, compression, combustion, and exhaust cycles. Diesel combustion produces high-pressure gas, driving the piston and converting chemical energy to mechanical energy.
Drives Generator to Produce Electricity: The engine’s crankshaft turns the generator rotor, inducing current via the electromagnetic coil as it cuts through the magnetic field.
Outputs Electrical Energy: The generator delivers AC power to the ship’s electrical system.

Main Features of Marine Diesel Generators

High Reliability: Rugged design for long-term, high-load operation with low failure rates and maintenance costs.
Marine Environmental Resistance: Corrosion-resistant materials for seawater, high humidity, and salt spray; waterproof, rustproof, and saltproof construction.
Stable Operation: Shock absorbers and soundproof cover for low noise and vibration; stable voltage and frequency for onboard equipment stability.
Energy Saving & Environmental Protection: High-pressure common rail, turbocharging, and advanced exhaust treatment (SCR, DPF) for low fuel consumption and reduced emissions.
High Automation: Auto start/stop, load management, and automatic fault diagnosis/protection for enhanced safety.

Main Uses

Main Power Supply: Powers ship systems such as propulsion, cargo hold heating, and crew living facilities.
Standby Power: Provides emergency backup for essential functions (navigation lights, communication) in case of main power or shore power failure.
Specialized Power Supply: Supports refrigerated holds, drilling ships, research vessels, and other special equipment.
Auxiliary Power Supply: Supplements shore power, providing living power while docked in port.