Luoyang Water Supply Company Zhaodong Waterworks, the original 6 sets of equipment 220kW/6kV and three 650kW/6kV booster pumps. For a long time, relying on the abundant production experience of the water plant, the pressure of the pipe network of the water plant has been regulated through the combination of the size and the pump. However, the pressure of the export factory is not easy to control, and the operating intensity of the operator during the regulation and control process is great, and the electrical and mechanical impact of the equipment is great. When there is an unreasonable mix and match, it is easy to see that the pressure on the pipe network is too low or the pressure is too high. During the operation, there was a "burst" accident caused by excessive pressure.
With the increase of urban life production and water use, the time and volume of traffic throughout the day will increase. Artificially regulated system production and simple combination of size pumps not only do not guarantee effective and reasonable production, but also consume large amounts of electricity in vain. If there are accidents such as "burst explosion", the economic losses caused will be even greater. As a result, Luoyang water company through many years of research, the ultimate choice of Shanghai Branch Industrial Speed ​​Co., Ltd. SGC-F5060-650K high-voltage motor rotor frequency control device. The device is equipped with high-voltage and high-power motor speed regulation, and its performance is reliable. Equipment control performance is in full compliance with the process requirements for pumps and fans; price-performance ratio is the best in today's speed control equipment.
1, transformation
<1> Rebuild the 8# pump motor JR1510-6 Pe=650kW motor in the original equipment system into the internal feedback speed-regulating motor. The motor production plant is Shenyang Motor Plant. The model number is JRNT1510-6 Pe=650kW and the speed is 983r/min-600r. /min. <2> Install a set of SSC-F5060-650kW inner-feed high-frequency chopper speed regulator produced by Shanghai Keyuan Speed ​​Electric Co., Ltd. on site. <3>The pressure transmitter and PID were added to the site, and the closed loop control was performed with the speed controller. <4> In consideration of the industrial-grade touch type man-machine interface used by the speed governing device, good performance, high reliability, convenient configuration and data communication, an additional man-machine interface of the same model of the central control room is added. It has the same content control and process picture, and master-slave difference. The process parameter table can accurately control when the system is automatically controlled. It can also be manually controlled when needed. <5> The actual line distance between the field speed control device and the central control room is 85 meters, and an RS485 communication data line is added.
2, debugging
<1> After the motor no-load full speed, no-load speed regulation. <2> Motor load full speed, manual load speed control, automatic load control (PID closed loop). <3> Control during manual setting (PID closed-loop control). When the automatic setting (PID closed-loop control) process control and other stages of the state of the operation and debugging. In the actual stand-alone operation, when the motor speed is adjusted to 626r/min, the active power has been reduced to 26kW. When the motor speed is adjusted to 972r/min, the active power is 621.44kW. (current 65A, voltage 6kV, cos Ñ„ = 0.92)
3. Added process production program function for waterworks
In order to make the user feel more simple, intuitive, and record the data during actual use, in order to achieve the optimal water supply, this device has augmented part of the hardware and software used in process production, and has realized multi-period automatic variable pressure water supply. Reduce water pressure during periods with less water, increase water pressure at peak water supply, increase water quality, and reduce energy consumption:
<1> Add the slave touch screen of the central control room, built-in process production screen, history curve screen clock adjustment screen, and operation process guidance screen.
<2> Newly added motor speed, pressure setting, pressure sampling and uploading analog quantity, the operator is clear at a glance, the operation is convenient and simple, the process control can be automatic, but also can be manually when needed, which greatly facilitates the production process control.
<3> New equipment failure alarm, process alarm, acousto-optic system. There are information prompts in the touch screen to enable operators to make timely judgments and operations on emerging equipment and process problems.
to sum up
Luoyang Water Supply Company Mindong Waterworks Co., Ltd. has used the SGC-F5060-650kW feed-in high-voltage motor rotor frequency conversion speed-changing device to transform the water pump No. 8 pump: the waterworks staff has brought convenience in operation; the output pressure of the pipe network has been accurately controlled. The pressure control error is within ±0.003 MPa, which solves the fluctuation of pipe network pressure for a long time, eliminates the “burst pipe†accident that may be caused by high pipeline pressure, and improves the quality of water supply. It also reduced water and water consumption for water plants by 10,000 tons. The adoption of a high-voltage rotor frequency conversion speed regulation scheme has improved the production process, simplified the system operation, reduced the labor intensity of employees, reduced equipment losses, reduced the consumption of electrical energy, and improved the quality of water supply. It is worth promoting and applying in the water supply industry.