Our Company Participated in The Renovation Project Of Reactive Power Compensation Cabinets in The Grain And Oil Factory in Hubei Province.

Our company dispatched technical personnel to inspect the operational status of the compensation cabinet in the Hubei Grain and Oil Factory after the renovation. They also conducted a detailed analysis and operation training for the compensation cabinet in the Hubei Grain and Oil Factory. Based on the on-site cabinet surface instrument data, as well as the operation conditions of the compensation cabinet before and after the renovation, the analysis results are as follows:

 

1.Load condition analysis

 

The grain and oil factory in Hubei mainly engages in the production, processing and sales of oilseeds, oil materials, vegetable oils, protein meal and their deep processing products. The workshop equipment is mainly composed of electric motors, and there are a large number of them. Most of the equipment contains frequency converters (during the operation of the frequency converters, some harmonics will be generated, mainly 5th, 7th and higher harmonics), and the power factor of the equipment is relatively low. The transformer requires a large amount of reactive power compensation. The production mode of the enterprise is 24-hour continuous operation, so the compensation cabinet is also in a long-term working state.

 

2.The operation status of the compensation cabinet before renovation

 

According to the description provided by the technical staff in the factory and the feedback from the site, before the compensation cabinet was renovated, there were multiple incidents such as fuse explosions, burning of the power leads of the capacitor, high temperatures of the reactor, severe capacity reduction of the capacitor, and fires in the compensation cabinet. As shown in the following pictures:

 

3.Post-reconstruction operation results:

 

①Three 2500KVA transformers have different original power factors due to varying loads, and thus the compensation amounts of the compensation cabinets also differ.

1# transformer and 28 intelligent capacitors have all been put into operation. After compensation, the power factor has reached 0.95. The compensation cabinets have no spare capacity.
2# transformer has 35 intelligent capacitors. There are 5 circuits that have not been put into use (the total capacity is 150 KVAR). After compensation, the power factor reaches 0.95, and the compensation cabinet has a certain margin.
3#There are 30 intelligent capacitors for the 3# transformer, and 9 of them have not been put into use (the total capacity is 270 KVAR). After compensation, the power factor reaches 0.94, and the compensation cabinet has a certain margin.

 

② During the commissioning of the intelligent capacitor, the system monitored the temperature of the reactor to be between 27℃ and 55℃ (randomly checking 22 units);
③ The harmonic voltage distortion rates of the three transformer systems did not exceed the national standards. The harmonic currents of transformers 1# and 2# did not exceed the standard values. However, the 5th and 7th harmonics of transformer 3 exceeded the standard values (refer to the summary of the operation data of T3 transformer).
④ During the operation of the compensation cabinet, the cooling fan inside the cabinet is functioning properly and the cabinet temperature is relatively low.
⑤ The intelligent capacitor shows no alarm or communication abnormalities.