What is the working principle of marine electromechanical systems

Marine generator sets generally adopt quasi synchronous juxtaposition. Assuming it is quasi periodic, in addition to the same phase sequence, it should also satisfy the same frequency and voltage of two generators, with fundamentally the same phase difference, and can be connected to the power grid. Before expulsion, the load should be reduced. When the sum of the power of two generators is less than or equal to the power of one generator, the circuit breaker of one generator can be disconnected, and attention should be paid to adjusting the frequency and voltage of the generator during operation to meet the requirements.

The use of marine generator sets as backup power sources is becoming increasingly common on ships. Due to their performance advantages, they have become an important component of propulsion systems for ships weighing thousands of tons or more, especially military vessels. There are usually three or more generator sets, with two for daily use and one for backup. It is necessary to merge and use two generators; It is necessary to meet four conditions when communicating with generators: the phase sequence of generators operating in parallel must be the same; It is necessary for generators operating in parallel to have the same voltage; It is necessary for generators operating in parallel to have the same frequency; It is necessary for the generators of four parallel trains to have the same phase angle; Assuming there is a control box around the generator, pressing the start generator button on the distribution panel will receive the signal from the generator side box and control the corresponding starting equipment to start the generator** The secondary wiring is qualified, and the second and third parallel operations are carried out. Adjust the excitation of the generator to make the voltage equal; Adjust the speed of the prime mover to make the frequency the same; Fourthly, it is difficult to have the same phase angle. The rough synchronous parallel operation mode is usually adopted on board, that is, the parallel reactor is connected between the parallel generators. After meeting the above conditions, when the synchronization indicator approaches zero and the parallel switch is closed, the two generators are connected together through the parallel reactor. At this moment, under the constraint of the reactor, the circulating current between the two generators is within the allowable range, which will synchronize the two generators.