Tag Archives: sensorless brushless motor

sensorless brushless hub motor at low speeds

Sensorless brushless hub motor at low speeds and easy low-frequency vibration. Vibration frequency and load and drive performance, generally considered the vibration frequency is half the frequency of the hub motor load off. By the sensorless brushless hub motor that works the low-frequency vibration determined by the normal operation of the machine is very negative. When working at low speed sensorless brushless hub motor, generally should be used to overcome the low-frequency vibration damping phenomena, such as the increase in the damper motor, or drive on the use of segmentation techniques. AC servo motor is running very smoothly, even at low speed vibration will not occur. AC servo system with a resonance suppression, can cover the lack of mechanical stiffness, and function within the system has a frequency analysis (FFT), can detect mechanical resonance point, easy system tuning.

sensorless brushless hub motor power grid conditions

sensorless brushless hub motor power grid conditions

Empty factory electronic control system of a power station from the higher blood pressure, voltage 6kV, step-down station outlet side of the maximum and minimum short-circuit capacity: Smax = 230MVA, Smin = 130MVA; Buck branch voltage power distribution station to empty rooms distance 400m, 185mm2 copper power cables from the two parallel transmission, converted to an empty factory 6kV cable into the line at the maximum and minimum short-circuit capacity:

Sbsmax = Sj / (Sj / Smax + XL) = 212.31 MVA
Sbsmin = Sj / (Sj / Smin + XL) = 123.46 MVA

Where Sj-base capacity, take 100MVA
XL-cable reactance per unit, XL = 0.041 Ω

Therefore, the empty factory 6kVA bus minimum and maximum capacity: Sbsmax = 212.31MVA, Sbsmin = 123.46 MVA; empty factory 6kVA single bus segment bus is running, 3700kW motor connected to the higher level bus segment Ⅰ, Ⅰ pre-bus segment connected load reactive power: Qx = 2.10MVA.

sensorless brushless bike motor of the main technical data

The ASU uses Shenyang Blower Factory production turbine air compressor, the drive motor for the Shanghai Motor Factory production T3700-4/1430 large high-voltage synchronous motor.

Motor parameters: Rated power: 3700kW; Rated voltage: 6kV; Rated current: 408A; Rated capacity: 4235kVA; starting current multiple of: 6 times; power factor: cosΦ = 0.9; Frequency: 50Hz; speed: 1500r/min; motor starting torque moments of relative value: 1.8; static resistance torque relative value units: 0.3; synchronous motor pull-in torque relative value: 1.18; flywheel torque: 385kg.m2; maximum allowable motor starting time: 40s; motor allows the number of consecutive starts: 2 times.