Because the actual flow of the pump is smaller than the rated flow of the pump, the potential for energy savings is greater. Water injection pump control system by the inverter through the transmitter feedback pressure value, and the preset in the inverter in the pressure value comparison, the inverter in the pid regulator automatically adjusts the difference based on the control of frequency control At the same time, the inverter operating parameters through the internal computer interface and communication protocol transmitted to the computer workstation; in the computer can at any time detection and control of system operating pressure, motor speed, input / output voltage, input / output current, etc. Parameters, to achieve the purpose of automatic energy-saving system. Inverter system and the original control system comparison 1) The use of frequency control, its easy operation, no need to manually adjust the inlet valve, which greatly reduces the labor intensity of workers and improve work efficiency. 2) Starting noise is low, the motor accelerates slowly from low frequency during start-up, and reaches the set frequency after 20 seconds. As the starting current is small, the impact on the power grid is reduced, the electric equipment is protected, the motor is prolonged Life, improve the efficiency of the motor, save maintenance costs. 3) The system uses one-tow two control mode, the pressure transmitter feedback current signal (4-20ma) to the inverter central processing unit (cpu), the pid control form a closed-loop control system. The output frequency of the size of the role of the processor control, the motor speed automatically increase or decrease; when the pressure exceeds the set target value (ie,> 5%) of which the first motor to power frequency operation, the inverter starts Two Taiwan motor frequency operation, to maintain constant water pressure. This will not only reduce the motor reactive power, but also improve the efficiency of the pump, saving energy. 4) Ordinary power frequency control mode (the original control mode) can not achieve the purpose of starting and stopping the need for human operation, but also need to adjust the inlet valve to meet the operating conditions, that is time-consuming and laborious, and Prone to operational errors, resulting in unnecessary losses. Power frequency operation control motor speed is not adjustable, and the starting current, when the water supply pressure exceeds the required pressure value when the need to manually adjust the size of the inlet valve to meet the water pressure. At this time the motor is still running at full capacity, excess power is consumed on the valve, a great waste of energy. From the above analysis of the actual conditions, the use of frequency control methods to meet the production needs, making the injection pump can be large flow, but also a small flow, both high-pressure, but also low-pressure operation. You can use pressure closed loop or flow closed-loop control of water pressure or flow, filling station conditions change, the inverter can make the water injection pump automatically adjust the injection pump pressure or flow. At this point, the pump's outlet valve is fully open, reducing the pump differential pressure to zero. This saves energy and reduces the amount of valve maintenance. It also increased the level of automation of the system, reduced the system noise, improved the working environment and reduced the labor intensity of the workers. The use of frequency control to obtain the actual flow of water, not only saves energy and improve system automation; inverter automatically adjust the speed according to demand, and smooth and stable, reducing the labor intensity of staff; pump operating parameters can be improved, System efficiency greatly improved.