The application status and development prospect of inverter

The speed regulation of the inverter is to use the voltage frequency ratio to regulate the speed, and I believe that people can definitely find other methods.

Impossible, you can be mistaken, now AC speed regulation is replacing the original DC speed regulation in large quantities. Now the inverter is developing towards high power. How could it be eliminated. There is no better way to regulate the speed. Is it back to the steam turbine push?

It's in the United States, but it's good to have such an idea.

1. One of the biggest advantages of inverter is energy saving.

The most obvious industry is the application of the fan and pump industry. Because the power consumption of the fan pump is proportional to the cube of the speed, when the external air water consumption is not high, the speed is reduced by using frequency conversion, and the energy-saving effect is obvious. The principle of energy saving in other industries is more or less the same, which is achieved by reducing the speed of the motor when it is not required to run at full speed.

2. It can be soft start, which is energy-saving and prolongs the service life.

When the motor is directly started by the power frequency, it will produce 7 to 8 times the rated current of the motor, and the increase of the current increases the electrical stress of the motor winding and generates heat, thereby reducing the service life of the inverter. The frequency conversion speed regulation can be started at zero speed and zero voltage (torque can also be increased appropriately).

3. The control system is simplified.

The variable frequency speed regulation can be started at zero speed and accelerate evenly according to the user's needs, and the acceleration curve can also be selected (linear acceleration, S-shaped acceleration or automatic acceleration). The operating speed can be adjusted at any time as needed, and can be quickly changed according to the process, and the speed can also be changed by remote control PLC or other controllers.

4. Reduce mechanical wear and tear.

When starting by power frequency, there is a violent vibration on the motor or the connected mechanical part, shaft or gear. This vibration will further exacerbate mechanical wear and tear, reducing the life of mechanical components and motors. In the frequency conversion speed regulation, the stopping mode can be controlled, and there are different stopping modes to choose from (deceleration stop, free stop, deceleration stop + DC braking), which can reduce the impact on mechanical parts and motors, so that the whole system is more reliable, and the life will be increased accordingly, improving the stability of the system.

Inverter is widely used, according to the voltage level of low-voltage inverter and medium and high voltage inverter, the purpose and demand of various industries are different:

Petroleum: oil pumps, electric submersible pumps, water injection pumps, pumping units, etc.

Chemical: extruders, film conveyors, mixers, compressors, blowers, sprayers, pumps, etc.

Iron and steel: rolling mills, roller tables, fans, pumps, cranes, ladle cars, converter tilting, etc.

Metallurgical industry: rolling mills, roller tables, blast furnace fans, pumps, lifting machinery, blast furnace feeding, steel mill polishing, etc.

Rolling line: wire drawing machine, winding machine, blower, pump, lifting machinery, cut-to-length shearing, automatic feeding.

Construction: elevators, conveyor belts, air conditioning equipment, blowers, pumps, etc.

Electricity: boiler drum blowers, feed pumps, centrifugal mixers, conveyor belts, hydroelectric power stations, flywheels, etc.

Mining: mud pumps, conveyor belts, hoists, cutters, excavators, cranes, blowers, pumps, compressors, etc.

Transportation: electric vehicles, electric locomotives, ship propulsion, air compressors, cable cars, etc.

Cement: rotary kilns, lifting machinery, blowers, pumps, main drive motors, conveyor belts, vertical kiln fans, etc.

Paper industry: paper machines, pumps, pulverizers, fans, mixers, blowers, etc.

Electronics manufacturing industry: air compressors, injection molding machines, air conditioners, fans, pumps, conveyor belts, etc.

The development direction of the inverter is that the small and medium-power inverters are all made inside the motor, and the control line is drawn out, which can jointly use the heat dissipation system temperature of the motor, and the current and other sensors require shorter wiring and occupy less space. Now individual motors already have this kind of practice.

The general direction is to eliminate a large number of small and medium-sized enterprises that are not strong and uncompetitive, and the current market is becoming saturated.