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A new method for mitigating frequency fluctuations in ships with electrical propulsion.

B Payvand¹, S M Hassan Hosseini¹

¹Electrical Engineering Department, South Tehran Branch, Islamic Azad University, Tehran, Iran.

ISA Transactions

|March 17, 2019

Summary

This study introduces a new frequency controller for ship electrical networks to prevent blackouts and equipment malfunction. The controller mitigates frequency fluctuations, especially when diesel generator response is poor, ensuring stable power for propulsion drives.

Keywords:

Blackout Electrical propulsions Mitigating frequency fluctuations Ships

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Area of Science:

Electrical Engineering
Marine Engineering
Control Systems

Background:

Ship electrical networks face generation capacity limitations, leading to frequency instability and potential blackouts, particularly with electric propulsion.
Existing load reduction methods suffer from time delays and require sophisticated real-time management to avoid miscalculations.
High frequency fluctuations, even within limits, can impair sensitive equipment, crucial for military applications.

Purpose of the Study:

To develop and implement a continuous frequency regulation technique for ship electrical systems.
To enhance the stability and reliability of ship power grids, especially during critical conditions.
To minimize the impact of frequency fluctuations on sensitive onboard equipment.

Main Methods:

An electromechanical model of the ship's electrical system was developed.
A novel frequency controller was designed and integrated into the system.
The direct torque control (DTC) method was employed to investigate the propulsion drive's basic controller.

Main Results:

The proposed frequency controller effectively regulates system frequency, minimizing fluctuations.
The controller demonstrates minimal impact on normal propulsion drive operation.
It actively mitigates frequency deviations when diesel generator performance is suboptimal.

Conclusions:

The developed frequency controller enhances the stability of ship electrical networks.
This approach provides a robust solution for preventing blackouts and protecting sensitive equipment.
Continuous frequency regulation is vital for reliable ship power systems, especially in demanding applications.