6,600 VOLTS HIGH VOLTAGE MAIN SWITCHBOARD

Summary

This video explains the power management system (PMS) on board a container ship, covering the flow of electricity from the ship's four generators to various essential loads like boilers, compressors, and navigation equipment. It details the system's setup, including main and emergency switchboards, transformers, and generators, and how they work together to ensure efficient power distribution. The automatic control system is highlighted, ensuring the seamless operation of the electrical plant, with a focus on synchronization, load sharing, and emergency response during power failures. The video is a comprehensive guide to understanding the vessel's electrical setup and safety protocols.

Takeaways

• ⚡ The video explains the power management system on board a container ship, showing how electricity flows from generators to various loads like boilers, compressors, and steering systems.
• 🔋 The vessel has four generators located in the engine room on the second deck, each producing 6600 volts at 60 hertz with a nominal load of 2800 kilowatts.
• 🧭 The main switchboard, located in the engine control room, distributes power and is managed either manually, semi-automatically, or automatically through the Power Management System (PMS).
• 🤖 The PMS automatically handles generator operations, including start-up, synchronization, and load sharing to ensure efficient and balanced power distribution.
• 🔌 The system includes vacuum circuit breakers (VCBs) and bus bars divided into two sections (A and B), separated by a main bus tie that allows servicing one side while keeping the other operational.
• ⚙️ Electricity from the 6600V main switchboard is stepped down to 440V through two 4200 kVA transformers, and further down to 230V via 150 kVA transformers for smaller equipment and lighting.
• 🧯 The 440V switchboard powers essential ship machinery such as winches, cranes, pumps, blowers, and boilers, while the 230V section supplies navigational, alarm, lighting, and accommodation systems.
• 🚨 The emergency switchboard, located in the emergency generator room, supplies power to critical systems like fire pumps, steering gear, and firefighting equipment during blackouts.
• 🧩 Transformers and breakers are interlocked to ensure only one source feeds each bus section at a time, enhancing safety and preventing electrical faults.
• ⚠️ In case of a blackout, the emergency generator automatically starts within 45 seconds, restoring power to the emergency switchboard and essential systems.
• 📈 The system design ensures reliability, redundancy, and safe operation of the ship’s electrical network through careful synchronization, interlocking, and automated load management.

Q & A

What is the main purpose of the power management system on board the vessel?

The power management system controls the flow of electricity from the generators to various machinery on the ship, ensuring that all systems, such as the boiler, air compressor, purifiers, and steering gear, receive the necessary electrical power to operate efficiently.

How many generators are there on board, and what is their function?

There are four generators on board. They supply 6600 volts at 60 Hz to the main switchboard, providing electrical power to the ship's systems as required based on the load.

How does the number of running generators depend on the electrical demand of the ship?

The number of generators running at any given time depends on the electrical load of the ship. The system adjusts the operation of the generators based on this load, and it can operate manually or automatically.

What is the role of the vacuum circuit breaker (VCB) in the system?

The vacuum circuit breakers (VCBs) connect the generators to the busbars and protect the electrical circuits. They play a key role in controlling and isolating the electrical circuits in case of faults or maintenance.

What are bus bars A and B, and how are they connected?

Bus bars A and B are part of the main switchboard, each handling different loads. They are normally separated but can be connected via a main bus tie (VCB), allowing the power supply to be distributed across both bus bars for even load distribution.

What is the function of the 6600 to 440-volt transformers?

The 6600 to 440-volt transformers reduce the high-voltage electricity from the generators to a lower 440 volts, which is required to power the low-voltage systems on board, such as winches, ventilations, and other machinery.

How does the emergency switchboard function in case of a blackout?

In the event of a blackout, the emergency generator will automatically start within 45 seconds, and the emergency circuit breakers will close, ensuring that essential systems, like fire pumps and steering gear, continue to operate.

What is the purpose of the interlocks between the circuit breakers in the system?

The interlocks ensure that only one circuit breaker can be closed at a time to prevent power conflicts. For instance, only one of the transformers can be connected to the 440V section at any time, and only one emergency bus tie can be active to prevent overloads.

What does the Power Management System (PMS) do automatically?

The PMS automatically manages the operation of the diesel generators, including starting them, synchronizing them to the bus bar frequency, and sharing the load equally between the generators for efficient operation.

What happens during the synchronization of a new generator with the running ones?

Before a new generator is added, its frequency, voltage, and phase sequence must match the running generator(s). Once these conditions are met, the generator can be synchronized manually or automatically with the existing system.