What is called the high voltage frequency conversion scheme
Main loop system scheme
Considering the actual operation of the equipment on site, Yituo second-hand dynamic bypass mode using coal mine main fan axial flow fan frequency conversion system, using a frequency converter were individually driven two typhoon machine in a typhoon machine motor, under normal circumstances, allowing a load is working in the inverter state, another load work in the frequency of the state, two are in the frequency of the dynamic state without compensation;
The series of frequency conversion using a number of low-voltage PWM inverter power unit in series to achieve direct high voltage output. Inverter with harmonic pollution to the power grid minimum input power factor is high, the output waveform quality good, there is no problem of the harmonic caused by the additional heating of motor, torque ripple and noise and DV / dt and common mode voltage characteristics, does not need to add the output filter, you can use ordinary asynchronous motor, do not need to replace the motor.
Field system condition
Because of the particularity of the coal mine production, the mine ventilation system is related to the safety production of mine, so the ventilation system plays an important role in the coal production. The main fan in coal mine production is the most important position, extends unceasingly along with the mining and excavation, extending the roadway, although volume basically unchanged, but the wind pressure is increasing, fan needs the power also increases. According to the function of anti wind and mining later to determine the main fan machine and the driving motor power is usually much larger than the long-term coal mining for the normal operation of power. Five ditch coal mine main fan using 500KW/6KV motor drive, motor with direct starting mode.
The start of high voltage motor, there are several problems:
A serious waste of energy. The service period of the coal mine mostly in more than 60 years. At the beginning of production to the stabilization of mine mining general in about 10 years. This means that the 10 years of time, the main fan has been in lighter loading operation. Because the speed of motor power frequency operation can not be adjusted, only the adjustment is made by changing the blade angle, thus resulting in energy waste, increase the cost of production.
It is difficult to start, serious mechanical damage. Using the main fan directly. The starting time is long, large starting current, the motor insulation has a greater threat, serious when even burning of the electric motor. Single axis torque motor to generate the phenomenon in the process of starting the fan vibration of high stress, the serious influence to the motor, fan and other mechanical service life.
The low degree of automation. The main fan rely on artificial regulation of wind turbine blade regulating air volume and pressure, but do not have the air automatic real-time adjustment function, degree of automation is low. In case of a fault condition, such as air circuit, will seriously affect the normal production of coal mine.
In order to mine safety in production and reduce the production cost, improve the automation level of the coal mine, on the main fan of frequency conversion transformation has very important significance.
Considering the actual operation of the equipment on site, Yituo second-hand dynamic bypass mode using coal mine main fan axial flow fan frequency conversion system, using a frequency converter were individually driven two typhoon machine in a typhoon machine motor, under normal circumstances, allowing a load is working in the inverter state, another load work in the frequency of the state, two are in the frequency of the dynamic state without compensation;
The series of frequency conversion using a number of low-voltage PWM inverter power unit in series to achieve direct high voltage output. Inverter with harmonic pollution to the power grid minimum input power factor is high, the output waveform quality good, there is no problem of the harmonic caused by the additional heating of motor, torque ripple and noise and DV / dt and common mode voltage characteristics, does not need to add the output filter, you can use ordinary asynchronous motor, do not need to replace the motor.
Field system condition
Because of the particularity of the coal mine production, the mine ventilation system is related to the safety production of mine, so the ventilation system plays an important role in the coal production. The main fan in coal mine production is the most important position, extends unceasingly along with the mining and excavation, extending the roadway, although volume basically unchanged, but the wind pressure is increasing, fan needs the power also increases. According to the function of anti wind and mining later to determine the main fan machine and the driving motor power is usually much larger than the long-term coal mining for the normal operation of power. Five ditch coal mine main fan using 500KW/6KV motor drive, motor with direct starting mode.
The start of high voltage motor, there are several problems:
A serious waste of energy. The service period of the coal mine mostly in more than 60 years. At the beginning of production to the stabilization of mine mining general in about 10 years. This means that the 10 years of time, the main fan has been in lighter loading operation. Because the speed of motor power frequency operation can not be adjusted, only the adjustment is made by changing the blade angle, thus resulting in energy waste, increase the cost of production.
It is difficult to start, serious mechanical damage. Using the main fan directly. The starting time is long, large starting current, the motor insulation has a greater threat, serious when even burning of the electric motor. Single axis torque motor to generate the phenomenon in the process of starting the fan vibration of high stress, the serious influence to the motor, fan and other mechanical service life.
The low degree of automation. The main fan rely on artificial regulation of wind turbine blade regulating air volume and pressure, but do not have the air automatic real-time adjustment function, degree of automation is low. In case of a fault condition, such as air circuit, will seriously affect the normal production of coal mine.
In order to mine safety in production and reduce the production cost, improve the automation level of the coal mine, on the main fan of frequency conversion transformation has very important significance.
| Datetime：2016.03.29 From： Views：