The energy saving of 1.lnovance inverter is mainly manifested in the application of fans and pumps. In order to ensure the reliability of production, all kinds of production machinery have a certain margin when designing power drive. When the motor can't run at full load, the excess torque not only meets the requirements of power drive, but also increases the consumption of active power, resulting in the waste of electric energy.
2.2. 1 The traditional speed regulation method of variable frequency fans, pumps and other equipment is to adjust the air supply and water supply by adjusting the opening of the inlet or outlet baffles and valves, which has a large input power and consumes a lot of energy in the process of intercepting baffles and valves. When frequency conversion speed regulation is adopted, if the flow requirement is reduced, the requirement can be met by reducing the speed of pump or fan.
3. The purpose of using frequency converter in motor is to adjust speed and reduce starting current. In order to generate variable voltage and frequency, the equipment must first convert the alternating current of the power supply into direct current (DC). This process is called rectification. A device that converts direct current (DC) into alternating current (AC) is called "inverter" in scientific terms.
4. Universal inverter is an inverter that converts DC power supply into a fixed frequency and voltage. For an inverter with adjustable frequency and voltage, we call it a frequency converter. The output waveform of frequency converter is analog sine wave, which is mainly used for speed regulation of three-phase asynchronous motor, also called frequency conversion governor. For the variable frequency power supply mainly used in instrumentation testing equipment, it is necessary to sort out the waveform and output a standard sine wave, which is called variable frequency power supply.
5. The general frequency conversion power supply is 20 times the price of 15- inverter. Because the main device that produces varying voltage or frequency in inverter equipment is called "inverter", the product itself is named "inverter", that is, inverter.
6. Frequency conversion can't save electricity everywhere, and it doesn't necessarily save electricity in many occasions. As an electronic circuit, the inverter itself consumes electricity (about 3-5% of the rated power). An air conditioner with 1.5 horsepower consumes 20-30W, which is equivalent to an ever-burning lamp. It is a fact that the inverter runs at the power frequency and has the function of saving electricity. But his prerequisite is:
7. Reactive power not only increases the line loss and equipment heating, but also reduces the active power of the power grid due to the reduction of power factor. A lot of reactive power is consumed in the line, which leads to low utilization efficiency and serious waste of equipment. After adopting the frequency conversion speed regulating device, the reactive power loss is reduced and the active power of the power grid is increased due to the function of the filter capacitor inside the frequency converter.
8. The hard start of the motor has a serious impact on the power grid, and it also requires too high power grid capacity. The large current and vibration generated during startup will cause great damage to baffles and valves, which is extremely unfavorable to the service life of equipment and pipelines. After using the frequency conversion energy-saving device, the starting current starts from zero and the maximum value does not exceed the rated current by using the soft start function of the frequency converter.
9. The frequency converter can be used for all mechanical equipment with motors. When the motor starts, the current will be 5-6 times higher than the rated value, which will not only affect the service life of the motor, but also consume more power. When designing the system, there will be a certain margin in the selection of the motor, and the speed of the motor is fixed. However, in actual use, it sometimes runs at a lower or higher speed, so it is very necessary to carry out frequency conversion transformation.
Frequency conversion drive is a power control device that uses frequency conversion technology and microelectronics technology to control AC motor by changing the frequency mode of motor working power supply.
The frequency converter is mainly composed of rectifier (AC to DC), filter, inverter (DC to AC), braking unit, driving unit, detection unit and microprocessor unit. The inverter can adjust the voltage and frequency of the output power supply by switching the internal IGBT, and provide the required power supply voltage according to the actual needs of the motor, so as to achieve the purpose of energy saving and speed regulation. In addition, the inverter also has over-current, over-voltage, overload protection and other protection functions. With the continuous improvement of industrial automation, frequency converters have been widely used.
Baidu Encyclopedia: Inverter