How to maintain the current loop of the generator set

The generator set is not prone to abnormal impact current, and the drive shaft is not subject to sudden impact. However, we should fully consider the overall current circuit problem in the whole process of parallel development, then how to maintain the circuit? The following is a brief analysis for everyone.

1. Reverse work

The inverse power condition is caused by the different speed ratio (frequency) and voltage of the generator set, that is, one generator set has positive power, while the other one has negative output power. In other words, the unit with negative output power becomes a load at this time (the unit has low frequency and inconsistent speed ratio). When the voltages are different, the unit with high voltage will present a reactive power current and reactive power voltage to the unit with low voltage (marked by the ammeter of this unit in the forward direction), which is equal to adding a phase regulating unit to the power supply and distribution system. At this time, the unit with low voltage becomes a large load and receives a very large reactive power current to maintain the voltage balance between the two units (the ammeter of this unit is marked in the opposite direction). During detection, the voltage of one unit is raised, or the voltage of another unit is raised or lowered, resulting in reverse power current of one unit, and the postural current is about 20% of the rated current. Reverse car relay position, power jump, alarm, but do not shut down.

2. Overcurrent

Today's generator set of high power, its overweight working capacity is very low, most of the high power of 5%, allow the load time of 15 to 30 minutes, the number is not more than an hour, beyond this time, the generator set will be hot, the transmission line insulation layer will be reduced, also reduce the use of time. Therefore, there is no special requirement when setting the overcurrent maintenance. It is OK to set the overcurrent maintenance at 110% of the rated current. When the load is detected, the current is brought to 110% of the rated current, overcurrent the car relay position. Power off, alarm, no shutdown.

3. Overvoltage

In parallel application of the generator set, the power supply and distribution system is afraid of shock, but the shock system software voltage rise, easy to lead to power consumption machine equipment and distribution equipment insulation layer penetration, so that the power distribution equipment and power consumption machine equipment together with hemiplegia. Therefore, generators used in parallel are equipped with overvoltage maintenance, and its preset value is 105% of the rated voltage is better. Short connection to voltage car relay, jump-off, alarm position.

It is not difficult to see that we must adjust the speed (frequency) of the two diesel generating units to be consistent before we prepare to carry out the parallel operation of the diesel generating units in advance. And in parallel, according to the rotation rate of the table, adjust the speed ratio of the first machine or to be combined with the unit, so that the table rotation azimuth, clockwise direction or reverse direction rotation, the slower the rate is better, but the table must rotate hands can be parallel. In parallel, check the current of the two units, the output power is not balanced, such as the difference is very big, adjustable rate knob, the output power of the two units to adjust to the same, so that can be trusted to maintain the safety of the loop.

Jiangsu Meao Power Technology Co., Ltd. is an important manufacturer of diesel generators. The company mainly manufactures and sells diesel generator sets with power of 3-3000kW, mobile power station of 24-600kW, Marine emergency diesel generator set of 24-800kW, gas generator set, heavy oil generator set and all kinds of imported series, special series (trailer, static speaker, mobile lighthouse, container, etc.) diesel generator At the same time, we are engaged in generator set maintenance and after-sale service of generator set accessories.