The working principle of frequency conversion feed pump

Frequency conversion is mainly to change the speed of the pump to adjust the flow, of course, there are some pressure control system, relays, solenoid valves, etc., the frequency converter regulator to be supplied by the relay in order to achieve automatic water supply, frequency conversion principle is to change the pump speed To control the displacement, so do not have frequent start and stop. The working principle is to change the speed of the motor according to the working conditions, with the motor speed to adjust the pump conditions
People say that the frequency conversion pump is actually a pump driven by a variable frequency motor. The advantage is to automatically maintain a certain constant pressure pump, so that the pump can work more effectively to meet the requirements of users, saving energy, the use of frequency converter to change the pump speed, to adjust the pump flow and pressure, the inverter in general Have closed-loop control function, can be automatically controlled according to the pressure signal operation, to achieve constant pressure water supply.
Frequency of feed pump working principle:
        1, variable frequency pump frequency conversion energy:
        From the fluid mechanics, P (power) = Q (flow) ╳H (pressure), the flow Q is proportional to the first power of the speed N, the pressure H is proportional to the square of the speed N, the power P is proportional to the cubic of the speed N , If the efficiency of the pump is constant, when the required regulation of flow down, the speed N can be proportional to the decline, while the shaft output power P set the relationship between the decline. That is, the power consumption of the pump motor and the speed of the approximate ratio of the establishment of the relationship. For example: a pump motor power of 55KW, when the speed down to the original speed of 4/5, the power consumption of 28.16KW, saving 48.8%, when the speed dropped to the original speed of 1/2, the power consumption The amount of 6.875KW, saving 87.5%, variable frequency pump power factor compensation for energy saving.CHECK out this website: http://www.dragon-pump.com to know APK company
        Reactive power not only increase the line loss and equipment heat, more important is the power factor to reduce the power grid caused by the reduction of active power, a large number of reactive energy consumption in the line, the use of equipment inefficient and wasteful by the formula P = S ╳COSФ, Q = S╳SINФ, which S-apparent power, P-active power, Q-reactive power, COSφ-power factor, we can see the larger COSФ, the greater the active power P, the general power of the pump motor power factor 0.6-0.7, the use of frequency control device, due to the role of inverter internal filter capacitor, COSФ ≈ 1, thereby reducing the reactive power loss, increasing the active power of the grid.
        2, the frequency of the pump's soft start energy saving:
        As the motor is directly activated or Y / D start, the starting current is equal to (4-7) times the rated current, which will cause serious impact on the mechanical and electrical equipment and power supply network, but also on the grid capacity requirements are too high, High current and vibration on the baffle and the valve damage greatly, the equipment, pipeline life is extremely unfavorable. The use of frequency conversion device, the use of the inverter soft start function will start the current from zero, the maximum does not exceed the rated current, reducing the impact on the power grid and the power supply requirements, extending the use of equipment and valves life. Saving equipment maintenance costs.