The Phenomenon of Reverse Power Transmission in Diesel Generator Sets

Each diesel generator set will be equipped with a load output switch for the customer. Before starting the diesel generator set, the load switch must be disconnected. Only when there is no current detected on the power grid after a power outage, can the current from the diesel generator set be transmitted to the power grid. At this point, it is necessary to ensure that the power grid switch is in a disconnected state, otherwise, when the mains power is restored, it is easy to experience reverse power transmission.

What is the phenomenon of reverse power transmission? What are the consequences of this phenomenon? Dingbo Power Generation Equipment tells you that the situation where your own diesel generator set sends electricity to the city grid is called reverse power transmission. There are two serious consequences:

1. If there is no power outage in the city grid, the power supply of the city grid and the power supply of the self-provided diesel generator set will cause asynchronous parallel operation, which will inevitably damage the diesel generator set. If the capacity of the self-provided diesel generator set is large, it will also cause oscillations in the urban power grid.

2. The city power grid has been cut off and is undergoing maintenance. If the self-provided diesel generator sets are powered back, it will cause electric shock and death for maintenance personnel in the power supply department.

Therefore, customers using generator sets must have their own separate grounding device for protective grounding and repeated grounding. Therefore, in addition to being connected to the casing of the generator, the grounding device should also be connected to the zero line of the generator, and the grounding resistance should meet the requirement of a grounding resistance of less than 4 Ω for generators of 100kW and above, and less than 10 Ω for generators of 100kW. This grounding device not only prevents the casing from being electrified due to generator leakage, but also more importantly, prevents zero drift when the three-phase load carried by the generator is unbalanced. If the grounding of the transformer is poor, resulting in reverse power transmission to the power grid, although the zero drift voltage is not very high, it will pose a threat to maintenance and construction personnel after the transformer is boosted. Especially in rural areas with relatively weak awareness, the grounding device of generators is more easily overlooked.

At the same time, it is necessary to strengthen the management of the power supply range of diesel generator sets, strictly prohibit users from privately connecting and transferring the electricity generated by the generator sets to other users for use. Strengthen the management of electrical operators for users to familiarize them with the switching operation procedures of diesel generator sets.

Guangxi Dingbo Generator Set Manufacturing Co.,Ltd is an early professional manufacturer of generators and diesel generator sets in China. The company has first-class national-level large-scale production and load testing equipment. Provide users with long-term diesel generator set sales, leasing, technical consultation, commissioning, maintenance, training services and generator set trusteeship business. If you would like to get more information welcome to contact us via sales@dieselgeneratortech.com.