What is the application of variable frequency speed control?
In the second half of the 20th century, the power electronic devices from the SCR (thyristor), GTO (gate can be turned off thyristor), BJT (bipolar power transistor), MOSFET (metal oxide field effect transistor), SIT (electrostatic induction transistor ), SIT (Electrostatic Inductive Thyristor), MGT (MOS Control Transistor), MCT (MOS Control Gate) to today's IGBT (Insulated Gate Bipolar Transistor), HVIGBT (High Voltage Insulated Gate Bipolar Thyristor), Device To promote the continuous development of power conversion technology. Since the 1970s, pulse width modulation variable frequency (PWM-VVVF) speed control research has aroused people's attention. In the 1980s, the PWM model optimization problem, which was the core of the frequency conversion technology, attracted people's interest and made many optimization modes, in which the saddle-wave PWM mode was the best. The 20th century, the late half of the 1980s, the United States, Japan, Germany, Britain and other developed countries VVVF inverter has been put into the market and widely used.
Generally used in the need for continuous speed control of the place.
With the general exchange of motor than its advantages is able to continuously speed.
DC motor, although also continuous speed control, but the price is expensive, the volume weight is too large.
Frequency control speed ratio is relatively large, in other words, the speed is accurate, smooth speed.
Widely used, the basic works can be used
Frequency conversion is to change the power supply frequency, thus regulating the load, play a lower power consumption, reduce losses, extend the service life of the role. Frequency translation.
Frequency conversion technology is the core of the inverter, through the conversion of the power supply frequency to achieve the motor speed regulation of the automatic adjustment of the 50Hz fixed-line frequency to 30-130 Hz change frequency. At the same time, also make the power supply voltage to adapt to the range of 142-270V, to solve the power grid voltage instability caused by electrical work problems. By changing the AC frequency of the way to achieve the AC control technology is called frequency conversion technology.
