Conditions for Parallel Operation of Diesel Generator Sets

As a power source, diesel generator sets are generally used in major projects, defense fortifications or ships. In order to meet the requirements of heavy load or uninterrupted power supply, two or more units need to be started for power supply at the same time. In order to ensure the reliability of power supply of diesel generator sets, improve the quality of power supply (voltage and frequency), increase the flexibility of operation, and achieve economic operation, it is often necessary to operate diesel generator sets in parallel. So, what are the conditions for parallel operation of diesel generator sets? Next, Starlight will discuss this problem in detail.

During parallel operation, huge impact current must be avoided to prevent synchronous generator unit from being damaged and power grid from being disturbed. At this time, the generator set shall meet four basic conditions electrically:

(1) Phase sequence The phase sequence of the output voltage of the generator set to be paralleled must be consistent with the phase sequence of the operating generator set;

(2) Frequency The frequency of output voltage of the generator set to be paralleled is equal to the frequency of the operating generator set;

(3) Voltage The voltage of the generator set to be paralleled is equal to the voltage of the generator set already in operation;

(4) Phase The phase of the output voltage of the generator set to be paralleled is the same as that of the voltage of the operating generator set.

If any of the above conditions is not met, circulation will occur due to different instantaneous values. The same phase sequence must be strictly observed, and the other three conditions are slightly different. Generally speaking, the phase sequence can be automatically satisfied by design, manufacture and installation. For motors without indication of direction and phase sequence, the phase sequence indicator can be used to determine. During parallel connection, the size and phase of frequency and voltage will be mainly checked.

Since 1982, Starlight Generator has been a generator set manufacturer qualified by the "National Internal Combustion Engine Quality Supervision and Inspection Center". The product quality has passed the IS09001 quality system standard certification. And obtained the qualification certificate for self-operated import and export. Over the years, starlight units have been widely used in all walks of life, and have won the network access qualification of the Ministry of Information Industry, the network access qualification of the Ministry of Radio and Television, the network access qualification of CNPC, the network access qualification of China Mobile, and the manufacturing qualification of marine units. In 2016, Starlight was awarded the Certificate of Qualified Supplier of China Nuclear Power Group. Starlight Generator has been cooperating with Shangchai Power for many years. In 2009, it became the OEM partner of Shangchai Power in China. Starlight generator VOLVO unit ranks the top three in the Asia-Pacific sales volume, and is the core OEM partner of Sweden Volvo VOLVO in the Asia-Pacific region. If any question please feel free to visit our website https://www.dieselgeneratortech.com/ or send email to sales@dieselgeneratortech.com.