The hottest variable speed drive responds to the s

  • Detail

In response to the slogan of "industrial energy saving", the variable-speed drive is becoming more and more popular in the market of recycled plastic granulator in te. After the variable-speed drive is used for fan control of cooling tower, it not only reduces the downtime, but also provides great potential for improving the overall power generation efficiency of the power station

the unidrive SP AC drive of Emerson CT was originally selected for practical reasons, because it is the only product that can be used for dol (direct start) motor starter in the structure control cabinet of 1. tension machine after improvement

jon Scott, a senior electrical control engineer of the power station operation company (PX Co., Ltd.), said: we need to replace six two-stage speed motors for a system of q501 cooling tower. Considering that the impact load on the blades, bearings and gear boxes will cause maintenance problems, we also need to provide feasible maintenance solutions. When comparing the cost of variable speed drive with that of AC induction motor which cannot be improved (the former is 20% of the latter), the bottom line of the two schemes is basically the same, but the other advantages of variable speed drive make the scheme more attractive. In order to make this project more cost-effective, we hope to continue to use the existing control cabinet, but its size is narrow. Only one drive product supplier Emerson CT can provide the products we need, and the drives they provide can adapt to our compact installation

under different loads and environmental conditions, the average inlet water temperature is 30 C. after cooling, the outlet water temperature is about 16.5 C. The water flow of the power station is 8000 kg/S (12 Olympic swimming pools can be filled in one hour, depending on the cycle time and pause time pool in the component program and processing), and it is required to provide about 460 MW of cooling power. This cooling power is provided by 22 fans. These fans produce an air flow of approximately 10500 kg per second (20400 domestic fans for the same flow)

the environmental conditions are very harsh, and the motor is vulnerable to high corrosion, Jon Scott added. The fan blades, bearings and gear boxes suffered from excessive wear, and the four quadrant system of PX Co., Ltd. had a longer downtime. Dol starters cause mechanical grabbing of large inertia components, Jon Scott explained. However, with variable speed drives, the fan can start slowly and gradually accelerate to two set speeds. Similarly, there is a step-by-step speed reduction process before shutdown. We believe that the maintenance of this system will be reduced

the company has improved six 132 kW unidrive SP AC drives. They are used for dol startup components, and each integration can be installed in a narrow control cabinet. The driver uses open-loop control and is equipped with onboard i/o to provide sequential control and connection for the current system, because PX company plans to install Ethernet module for data acquisition in the future. We worry that the drives will generate too much heat and noise, Jon Scott said, but in fact, these drives work very quietly and generate very little heat

after installing these drives, it is easy to find that the cooling tower has the potential to improve the efficiency of the power station after using variable speed drives. The drive system of PX is now controlled by the new variable speed drive, which runs faster and has better performance. Before, the wind on the site was very strong. Stefano scazzola, assistant performance engineer, said that we sometimes had to reduce the speed of the system, and sometimes we had to stop the fan due to vibration. The use of variable speed fans means that the complete system can be gradually reduced to an intermediate speed so that the system can continue to operate. The performance of the cooling tower is very important for the vacuum effect in the condenser on the turbine and the overall efficiency of the power plant

main advantages

less maintenance

potential to improve efficiency

steady increase/decrease in speed

can be improved for existing control cabinets

for more information, please visit

Copyright © 2011 JIN SHI