The system first changes the frequency through the inverter to change the speed, and the feedback signal from the pressure sensor, the inverter receives the feedback information and then performs the logic operation. After the logic operation, the required pressure value is obtained, and then the most reasonable current with a certain frequency is supplied to the motor. According to the principle that the speed is proportional to the frequency, the speed is optimally controlled. 1 1 Inverter High-performance V / F variable-speed high-speed controller CHF100 Inverter can achieve the purpose of adjusting the output speed of the motor by changing the frequency and voltage of the power input to the AC motor. The frequency converter receives the power frequency 50 Hz AC power from the power grid. After the appropriate forced frequency conversion method, the input power frequency is converted into an AC power whose frequency and amplitude can be adjusted to the AC motor to realize the variable speed operation of the AC motor. 1 2 pressure sensor pressure sensor adopts the most convenient two-wire input and output method at present, and converts the collected pressure signal into 4 20 mA standard analog signal pressure feedback to the inverter, the pressure sensor power supply voltage is 24 V. The main functions of the 1 3 power conversion conversion cabinet cabinet conversion cabinet are: automatic control of the inverter controller, and automatic control of the inverter through the inverter to the air compressor. When the inverter control system fails, the system automatically alarms, and the original system operation can be manually selected immediately. When the fault is found, the power is cut off manually. Displays current, voltage, frequency, output, PID feedback value, etc. in the current working state. 2 Energy-saving control system control mode The system controls two 132 kW air compressors for variable frequency power-saving operation. According to the specific conditions of the air compressor of the plant, the energy-saving equipment controls one motor to run, and the other one spares, and two motors can switch between the inverter control. However, this switching must be based on the premise of stopping the operation of the inverter. The system applies variable frequency speed control technology to constant pressure air supply control, which can take the pipe network pressure as the control object. The pressure transmitter converts the pressure of the gas storage tank into an electric signal and sends it to the intelligent regulator for comparison with the pressure setting value. According to the difference value, the operation is performed according to the predetermined control mode, and the control signal is sent to the frequency converter. The operating frequency and the rotational speed of the motor are controlled by the frequency converter, so that the actual pressure is always close to the set pressure, and the constant pressure air supply is achieved. In order to achieve constant pressure air supply on the gas pipeline, a pressure sensor is installed on the gas main pipe to convert the pressure in the pipe network into a 4 20 mA signal and send it to the intelligent self-tuning PID regulator. The PID regulator converts its input 4 20 mA signal to a voltage signal of 0 10 V DC, which is used as the frequency reference of the frequency converter to change the speed of the motor. When the system is working, the air compressor is running at variable frequency. If the pressure of the pipe network is not enough, the inverter will convert the pressure from the pressure sensor into a 4 20 mA analog signal. After the logic operation, the output will be the highest frequency set by the motor. . On the contrary, when the pipe network pressure is too high, the inverter will adjust the motor speed according to the actual air volume. The whole work process will make the pressure of the main pipe basically constant, and achieve the purpose of constant pressure gas supply. 3 system features (1) save energy. After the constant pressure air supply system is put into operation, the air pressure difference of the gas storage tank can be kept within 25% of the set value, which will reduce the electric energy lost by the automatic emptying, and the power factor is increased to cos > 0 95, which is reduced. Reactive loss. (2) Reduced noise and reduced environmental pollution. Since the constant pressure air supply system realizes the frequency conversion control, the situation of emptying and venting is basically eliminated, thereby improving the pollution of the environment by noise. (3) Extend the service life of mechanical components. After using the air compressor power-saving system, the air compressor runs under variable frequency conditions most of the time, which can significantly reduce the wear of mechanical parts, prolong the life of the machine, reduce maintenance costs and shorten maintenance time. (4) A soft start is implemented. Reduce the impact of the unit's starting current on the grid, and flexibly repeat multiple starts, avoiding the lack of auto-coupling step-down. (5) A constant pressure gas supply is realized. After the system is put into operation, the adjustment capability of gas supply reliability and load change is improved, a constant supply pressure is ensured, and the stability of product quality is further ensured. (6) The operation is reliable and the failure rate is almost zero. The system is equipped with overload, voltage loss, under voltage, over current and lack of protection functions, and the operation is reliable. (7) Easy operation, failure does not affect production. After the economizer fails, it can automatically stop and send a fault signal, which can be converted to the mains to make the air compressor operate normally without affecting production. 4 Conclusion Since the implementation of the transformation of the variable frequency energy-saving control system, the safety performance of the air compressor and the electronic control system has been further improved, and the performances are safe and reliable, which ensures the reliability of the air volume and the self-rescue system of the compressed air at various locations in the mine. After more than 1 year of operation, the power saving rate is 20%, the monthly energy saving is 16 790 kWh, and the annual electricity saving is 20 148 million kWh, saving 141.33 million yuan. YL 132kW 380V type frequency conversion energy-saving cabinet has complete protection functions, safe and reliable performance, simple maintenance, convenient operation and low power consumption. It is an ideal energy-saving equipment for coal enterprises. Wall Mounted Drinking Fountain Wall Mounted Drinking Fountain,Wall Mounted Outdoor Water Dispenser,Automatic Wall Mounted Drinking Fountain,Wall Mounted Water Dispenser GUANGDONG YUSHENG ENERGY SAVING ENVIRONMENTAL EQUIPMENT CO,.LTD , https://www.gduison.com