Why is single-phase use prohibited for three-phase AC synchronous generators?

Three-phase AC synchronous generator, why is single-phase use prohibited? Hazards of single-phase operation of three-phase AC synchronous generator

The three-phase AC synchronous generator is a commonly used power generation equipment that can stably generate high-quality electric energy. However, when using a three-phase AC synchronous generator, we must prohibit single-phase use, and there is a reason for this.

First, let us understand the working principle of the three-phase AC synchronous generator. The three-phase power supply consists of three AC power supplies with a mutual potential difference of 120 degrees, which are arranged in sequence on a ring-shaped power grid. By connecting these three-phase power supplies to the same generator, the normal operation of the generator can be achieved. Under normal circumstances, the three-phase AC synchronous generator will generate a stable three-phase current, which flows simultaneously in the loop and has a potential difference of 120 degrees between each other.

So what harm will single-phase operation cause to the three-phase AC synchronous generator?

First of all, single-phase operation will cause unbalanced load on the generator. Because the design of the three-phase AC synchronous generator is based on normal three-phase load operation, if only single-phase load is used, it will cause unbalanced load on the motor. And unbalanced load will cause increased motor vibration, accelerated temperature rise, and even cause serious consequences such as motor burnout.

Secondly, single-phase operation will cause unstable voltage and frequency in the motor. Under normal circumstances, the three-phase AC synchronous generator can stabilize the output voltage and frequency through the complementary effect of the three-phase power supply. However, when we only use single-phase load, the motor will produce unstable voltage and frequency because it cannot form a balanced distribution of three-phase current. Such fluctuations will not only damage the load equipment, but also threaten the stability of the power grid.

In addition, single-phase operation will also have a negative impact on the loss of the generator. Since the motor cannot form a uniform load, the current will be unevenly distributed in the circuit, some currents will be too large, and some currents will be too small, causing the bearings, windings and other components of the generator to bear uneven loads. This will not only consume the life of the motor, but also increase the maintenance cost of the motor.

In summary, there are good reasons to prohibit the use of three-phase AC synchronous generators in single-phase. Single-phase operation will cause unbalanced loads, unstable voltage and frequency in the generator, and even damage the motor itself. Therefore, in order to ensure the normal operation of the generator and extend its service life, we must resolutely prohibit the use of three-phase AC synchronous generators in single-phase. Only under normal three-phase load conditions can we give full play to the advantages of this generator and make greater contributions to society's power supply.