Variable Frequency Drive in Treadmill
A treadmill is common equipment in the modern family and fitness centers. With the belt system controlled by the motor, people can run or walk passively at different speeds. Besides, users can experience different running environment, such as flat land, uphill or variable speed to reach different training purposes, with the auxiliary electronic equipment on the treadmill. Most DC brush motors are used in the VFD system for the past treadmill to save cost. However, its weaknesses are the high failure ratio of carbon-brush and commutator device, high maintenance cost and inefficient low-speed torque. Thus, most manufactures adopt the AC motor with the variable frequency drive to improve the weaknesses of the DC motor.
The characteristics that Gozuk VFD applied in the treadmill are shown in the following:
1) Wider ranges of the carrier frequency: When using the VFD to control the motor, it will have a high-frequency electromagnetic noise. To have a quiet operation at home or fitness center, it reduces the noise by adjusting the carrier frequency of the VFD. The max. carrier frequency of Gozuk VFD is up to 15kHz for an unobvious noise.
2) Sensorless vector control: A stable motor output at different speeds is necessary for the different physical strength levels of runners. To reach this purpose, Gozuk VFD uses the sensorless vector control, which doesn't need any external speed feedback, for the induction motor runs stably at low speed. The torque can be 150% at 5Hz and the current wave of the motor when using treadmill is shown in the following diagram.
3) Lower level of the momentary low voltage: The new parameter, setting of low voltage level, in Gozuk exclusively designed VFD for treadmill used to set the level detection of low voltage by requirement to decrease the possibility of machine stop resulted from sudden load.
Gozuk VFD exclusively designed for treadmill improves the weakness of the general treadmill after researching the characteristics of each operation to be a popular VFD.
The characteristics that Gozuk VFD applied in the treadmill are shown in the following:
1) Wider ranges of the carrier frequency: When using the VFD to control the motor, it will have a high-frequency electromagnetic noise. To have a quiet operation at home or fitness center, it reduces the noise by adjusting the carrier frequency of the VFD. The max. carrier frequency of Gozuk VFD is up to 15kHz for an unobvious noise.
2) Sensorless vector control: A stable motor output at different speeds is necessary for the different physical strength levels of runners. To reach this purpose, Gozuk VFD uses the sensorless vector control, which doesn't need any external speed feedback, for the induction motor runs stably at low speed. The torque can be 150% at 5Hz and the current wave of the motor when using treadmill is shown in the following diagram.
3) Lower level of the momentary low voltage: The new parameter, setting of low voltage level, in Gozuk exclusively designed VFD for treadmill used to set the level detection of low voltage by requirement to decrease the possibility of machine stop resulted from sudden load.
Gozuk VFD exclusively designed for treadmill improves the weakness of the general treadmill after researching the characteristics of each operation to be a popular VFD.
