Skip to main content

What Are the Causes of Sudden Short Circuit of Diesel Generator Set


Because magnetic circuit and magnetic resistance for direct axis of synchronous generator is different from that of variable axis, the stator and rotor are in relative motion, so the mutual inductance coefficient and self-inductance coefficient of stator and rotor are not constant. It is difficult to analyze and solve by using differential equations, based on the principle of flux conservation in superconducting closed loop, explain from the physical concept, and derives the short circuit current in each winding when sudden short circuit occurs.

Characteristics of sudden short circuit for diesel generators

1.In the case of steady-state short-circuit, the steady-state short-circuit current is not large because of the large synchronous reactance, while in the case of sudden short-circuit, the sudden short-circuit current is large because the super-transient reactance limiting its current is very small and contains DC component. The peak value of the sudden short-circuit current can reach more than ten times of the rated current.

2.With the emergence of this impulse current, the winding of the electric motor will be affected by a great impulse electromagnetic force, which may cause the winding to be deformed or even the insulation of the winding to be damaged.

3.In the process of sudden short-circuit, the electric motor is affected by strong short-circuit torque, which can cause vibration.

4. Overvoltage occurs in stator and rotor windings of motors.



Characteristics of physical phenomena in generators during sudden short circuit

1.When in steady-state short circuit, the armature current is constant, and the corresponding armature magnetic potential is a constant amplitude rotating magnetic field rotating at synchronous speed, therefore, it will not induce electromotive force and generate current in the rotor winding. From the current relationship, it is equivalent to the open circuit state of transformer.

2.When short circuit occurs suddenly, the magnitude of armature current varies, and the corresponding magnitude of armature magnetic field varies. Therefore, the transformer between stator and rotor can induce potential and current in the rotor winding, and then affect the change of current in the stator winding. From the point of view of electromagnetic relationship, it is equivalent to the sudden short-circuit state of transformer.
标签：

Comments

Post a Comment

Popular posts from this blog

Diesel Generator Power Ratings: Standby vs Prime vs Continuous

Diesel generator sets are commonly used in a variety of sectors due to their dependable performance and high efficiency. They can be used for emergency power supply in the event of a power cut or used in places without connection to a power grid. When selecting a diesel generator for your home or business, you need to consider many factors, such as generator’s ratings. In this article, we’ll explain the three basic rating types - standby, prime, and continuous in diesel generators. ISO-8528-1:2018 defines basic generator set rating categories based on four operational categories: Emergency Standby Power (ESP), Prime Power (PRP), Continuous Power (COP) and Limited-Time Running Prime (LTP). Read on and learn the application of power ratings for engines used in generating sets. Standby Power Rating Standby Power(ESP) is used to supply emergency power when the external power supply is interrupted, such as power outages. Standby power rated generators can supply reliable electricity as t...
Post a Comment
Read more

What Should You Pay Attention to in Routine Maintenance of Diesel Generator Sets

In modern society, the stability of power supply is directly related to the operation efficiency of enterprises and people's quality of life. Diesel generators have become an indispensable backup power supply or main power source in various industries due to their high efficiency, durability and reliability. However, to ensure the smooth operation and optimal performance of the generator sets, regular maintenance is essential. Here is what you need to pay attention to in the routine maintenance of diesel generators. Keep your generator clean It’s important to keep the generator’s exterior and the generator room clean. Regularly remove any dirt, dust, or debris that may accumulate to on the generator’s surface. This is not only for the sake of beauty, but also for the smooth operation of the unit. Cleaning the generator’s exterior, air intake vents, exhaust outlets and generator room can effectively reduce the risk of generator overheating. In addition, check if the connection bol...
Post a Comment
Read more

How to Connect A Diesel Generator to Your House?

Diesel generators are fuel-efficient and reliable, which can almost meet the power needs of any application. If you want to power the whole house during power shortages, it’s a good choice to choose a diesel generator set as the backup electricity supply. But how to connect a diesel generator to your house? Read on and you will find the answer. Options to connect a diesel generator to your home   Keep in mind that never plug your generator directly into the mains, or it will cause back feeding, damage your appliances and be life-threatening for utility workers. Generally, you can choose to connect a generator to your house by using extension cords or a transfer switch. Understanding the difference between them is helpful for you to choose the right type. Extension cords   Typically, extension cords are suitable for smaller diesel generators that used for short term. They require no installation and are cost-effective. If you need to power only some basic appliances such as...
Post a Comment
Read more