1.The significance of frequency converter used in plunger pumps
Variable frequency speed regulation is to achieve the purpose of speed regulation by changing the frequency of power supply to the stator winding of the motor. Its basic principle is to convert the 50Hz industrial frequency power supply into an adjustable frequency power supply through rectification, voltage stabilization and inversion, which is applied to the motor. In order to achieve the purpose of adjusting the motor and speed.
By using variable frequency technology on a plunger pump, the flow rate of the pump can be controlled. In this way, within a certain range, the plunger pump will discharge the actual required flow rate, eliminating the ineffective backflow of the pump, improving the operating conditions of the pump, and reducing wear and tear on the equipment. Moreover, by using the frequency converter, the motor can start smoothly and the speed can be adjusted conveniently. It also has a good energy-saving effect under light load and low frequency.
2.Field application
In order to ensure the reliability of the equipment, it is required that the frequency converter can be manually switched to power frequency operation when it is inspected or damaged, and a frequency conversion switch is added so that the operator can switch freely according to the operating conditions. Taking into account the characteristics of one-use and one-standby equipment, the frequency conversion box electrical cabinet is designed with power frequency and frequency conversion to ensure foolproofness and production operation. Using a frequency converter can not only keep the pump in the best condition, but also save electricity.
3.Functions that can be achieved by using variable frequency speed regulation for the plunger pump load
3.1 The frequency converter has complete protection functions, which can automatically convert to power frequency operation when overvoltage, overcurrent, low voltage, phase loss, overload, short circuit and other faults occur, ensuring the normal operation of the plunger pump at all times.
3.2 Implement soft start function to protect the motor from large starting impulse current.
3.3 Operation can increase the power factor and improve the quality of motor power supply. The power of the motor matches the actual load, and the system achieves the purpose of energy-saving operation.
3.4 The number of revolutions of the plunger pump can be adjusted according to the flow rate and the frequency to meet the needs of production and energy saving.
3.5 Manual switching between variable frequency and power frequency can be realized to ensure the continuous operation of the equipment. When converting between industrial frequency and variable frequency, the operation must be stopped first, and the conversion and start can only be carried out after the motor has completely stopped running.
3.6 It is easy to operate. Through the control panel, you can check the cause of the fault and display the output voltage, output current, etc.
3.7 The frequency converter has communication function, which can realize remote centralization and facilitate detection of equipment operation.
4.The effect of using variable frequency piston pump
4.1 The plunger pump applies frequency conversion speed regulation technology, which can effectively improve the system working conditions, facilitate the adjustment of the output flow, save electricity, extend the service life of the feed, and reduce equipment wear.
4.2 The frequency converter reduces the motor speed by reducing the power frequency of the motor and adjusts the output frequency of the frequency converter to control the flow and ensure constant pipeline pressure. The pump displacement is reduced and the motor load is also reduced, so that the motor output The power is reduced, the efficiency of the motor is greatly improved, and the motor loss and motor output power are reduced to achieve energy saving.
4.3 Ceramic plunger pump high-power systems often operate like "big horses and small carts" with low efficiency. The slurry flow rate is manually controlled by the pump outlet gate, that is, the pump displacement is adjusted by changing the pipe network characteristic curve. It is difficult to match the pump and motor to operate under the best working conditions of the pump. The pipe network efficiency is low and the power loss is as high as above. It is from the considerations of flow rate and energy saving that variable frequency control is introduced in the slurry pump system.
4.4 Apply frequency conversion speed regulation technology to adjust the motor speed of the plunger pump to achieve stable voltage and stable flow of water. At the same time, the function of soft start and soft stop replaces the decompression start, making the motor start and stop smoothly, reducing the impact on the power grid and mechanical equipment, and will not cause drastic changes in the pressure, flow, and flow rate of the pipeline network, and does not require valve closure, so it is It is extremely beneficial to prevent cavitation, water hammer, and surge, and can extend the maintenance cycle and service life of pipe networks, pumps, and valves.