Requirements & Advantages of Generator Set Parallel Connection

 
In modern power systems, parallel operation of generator sets are crucial elements in ensuring stable power supply. Mastering the requirements for their parallel connection is essential. Additionally, diesel generator parallel operation possesses distinct characteristics that bring a series of advantages. This article delves into the requirements for generator set parallel connection, the advantages of diesel generator parallel systems, and the main characteristics of operating multiple generator sets in parallel.
 

Requirements for Generator Set Parallel Connection

 
To achieve effective parallel connection of multiple generator sets, a series of strict conditions must be met. These requirements involve aspects such as phase sequence, voltage waveform, frequency, voltage magnitude.
 
1. Consistent Phase Sequence: The output voltage phase sequence of two generator sets must be identical to ensure that there is no phase difference in voltage between phases when they are paralleled.
 
2. Identical Voltage Waveform: The voltage waveforms output by two generator sets must be consistent to maintain the electrical energy quality of the grid.
 
3. Close Frequency and Voltage: The frequency of two generator sets should be the same, and the phase and magnitude of voltage should be as close as possible to reduce the impact during parallel connection. Ideally, frequency and voltage should be adjusted to be fundamentally consistent.
 
4. Peripheral Equipment Adjustment: During paralleling, diesel engine speed can be adjusted through peripheral equipment to regulate frequency, and voltage values can be adjusted by adjusting the generator voltage regulator. This can be achieved through auxiliary paralleling modules, such as GAC synchronizing modules.
 

Advantages of Diesel Generator Parallel Systems

 
Fully automatic generator parallel systems equipped with synchronous control, load distribution modules, and automatic transfer switches have advanced performance, and the entire paralleling cabinet system is easy to use and maintain. For cases where multiple generator sets simultaneously supply loads, paralleling cabinets are necessary to ensure the reliability and economy of the grid. The main advantages of paralleling cabinets include:
 
1. Improved Reliability and Continuity of Power Supply: Multiple units paralleled into one grid result in stable voltage and frequency, capable of withstanding significant load variations, ensuring continuous power supply.
 
2. Convenient Maintenance: With multiple units paralleled, scheduling, distribution of active and reactive loads, maintenance, and repairs become more convenient and timely.
 
3. Economic Efficiency: By deploying an appropriate number of low-power units based on load size, fuel and oil wastage of high-power units during low loads is minimized, enhancing economic efficiency.
 
4. Scalability: Only installing generators and paralleling equipment for the current required power capacity, additional generator sets can be easily added when expanding grid capacity, making initial investments more economical.
 

Main Characteristics of Operating Multiple Generator Sets in Parallel

 

• Manual and Fully Automatic Paralleling Mode Selection: Users can choose between manual or fully automatic paralleling modes based on their requirements.
• Accurate Synchronous Paralleling without Impact: Paralleling time is short, not exceeding 3 seconds, ensuring grid stability. 
• Automatic Paralleling or Droop Based on Load Demand: The system automatically parallels or drops units based on load demand, making operation more economically efficient.
• Precise Load Distribution: When multiple units are paralleled, the difference in load distribution is less than 5%, ensuring the reliability and balance of unit operation.
• Automatic Start and Engagement: With the generator's self-start control module, automatic start and engagement occur during utility failures, followed by automatic disconnection and shutdown upon utility restoration.
• Comprehensive Protection Functions: The system includes protection functions such as reverse power, overcurrent, short circuit, mechanical faults, utility float charger faults indication, ensuring safety and reliability.
• Joint Use with ATS Cabinets: After utility restoration, the generator is automatically delayed for disconnection, transferring the load to the utility side. During utility failures, the generator starts automatically, transferring the load to the generator side, ensuring utility priority throughout the entire transition process.

 
Through the above content, a clear understanding of the conditions required for electronic speed-controlled generator set parallel connection, the advantages of diesel generator parallel systems, and the main characteristics of operating multiple generator sets in parallel is obtained. The detailed explanation of these points provides users with clear guidance in practical operations, ensuring the stability and economy of generator set parallel connection operations.