Reasons for Sudden Short Circuit When Generator Set Operation

Jul. 18, 2022

Due to the difference in the magnetic reluctance of the direct-axis and variable-axis magnetic circuits of the generator set, and the relative movement of the stator and the rotor, the mutual inductance coefficient and self-inductance coefficient of the rotor are not constant, and it is difficult to solve the differential equation analysis. As explained above, a sudden short circuit is derived, and the short circuit current of each winding is derived.

Introduction to the characteristics of sudden short circuit during the operation of the generator set:

During steady-state short-circuit, the steady-state short-circuit current is not large due to the large synchronous resistance. In the event of a sudden short circuit, due to the small super-transient resistance limiting its current and the presence of DC weight, the sudden short circuit current is very large, and its peak value can reach more than ten times the rated current. With the appearance of this inrush current, the windings during operation will be affected by a large impulse electromagnetic force, which may deform the windings and even damage the insulation of the windings.

In the process of sudden short-circuit, it may be affected by strong short-circuit torque during operation, which may cause vibration. Fixed rotor winding overvoltage during operation.

The characteristics of the internal physical phenomenon of sudden short circuit during operation: during steady short circuit, the armature current is constant, and the corresponding armature magnetic potential is a constant-amplitude rotating magnetic field rotating at a synchronous speed, which will not induce the potential in the rotor winding, generate current, and In terms of current relationship, it is equivalent to the open state of the transformer.

When a short circuit occurs suddenly, the magnitude of the armature current changes, and the amplitude of the corresponding armature magnetic field changes. Therefore, the transformer between the rotors induces potential and current in the rotor winding, which then affects the change of the current in the stator winding. From the point of view of electromagnetic relations, this is equivalent to a sudden short circuit condition of the transformer.

Jiangsu Starlight Power Generation Equipment Co., Ltd. was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. The company has a registered capital of 218.88 million yuan. The company covers an area of 86,000 square meters and a building area of 55,000 square meters. There are more than 660 employees, including 456 professional technicians and 106 senior technicians. It has 46 sales and service outlets nationwide. The main products are diesel engines, generator sets, and diesel generators, providing users with a one-stop service of design, supply, debugging and maintenance at any time. Starlight has always insisted on using first-class talents, building first-class enterprises, manufacturing first-class products, creating first-class services, and making every effort to build a first-class domestic enterprise. If any question please feel free to visit our website https://www.dieselgeneratortech.com/ or send email to sales@dieselgeneratortech.com.