bldc motor starting frequency is not too high, it is just starting because bldc motor speed is zero, the starting process, the load torque in addition to overcoming the resistance torque, but also to overcome the inertia of the rotating part of masking, so when the motor starter than in the burden of continuous operation as the most important.

If the starting pulse frequency is too high, the rotor speed to keep up with the speed of the stator rotating magnetic field, so the first step over the position far behind the equilibrium position, the subsequent step in the rotor speed increased marginally, while the stator magnetic field still pulse frequency proportional to the speed of forward rotation, the equilibrium position of the rotor and increasing the distance between the final position for the rotor dynamic stability region fell outside the emergence of-step or oscillation, and therefore the motor can not start.

In order to properly start, starting frequency is not too high, when the motor starts and then gradually increased frequency.

bldc motor winding open circuit the motor does not start, three-phase current imbalance, abnormal noise or vibration, temperature exceed the allowable value or smoke.

Winding open circuit due to poor welding or the use of corrosive fluxes, welding and then not cleaned, it may cause solder pot or loose; by mechanical stress or collision coil short-circuit, short circuit and ground fault also can lead burning, and burning in of a few wires in a short circuit or a few wires, the other a few wires as current as temperature rises, causing fever and winding circuit. Generally divided into disconnected end of one phase winding, inter-turn short circuit, parallel circuit branch office, multi-wire and burned in an open circuit, broken rotor cage.

hub motor short circuit causes:
1, when in the repair and maintenance problems touched off or manufacturing quality.
2, the winding of the components, pole (phase) winding and the lead group and the first welding wire and other wire bad, long-running hot sealing off.
3, by mechanical force and electromagnetic force or pull off the winding damage.
4, short circuit and the ground turns white sometimes cause severe burning or winding fuse and so on.

hub motor short-circuit approach:
1, open circuit at the end, the connection is completed weld, wrapped in insulating material, put pipe insulation, banding is good, and then dried.
2, as inter-turn winding, white short-circuit and ground and other reasons caused serious burnt windings should generally be replaced with new winding.
3, the open circuit point in the tank, is a small break to do emergency treatment, the use of groups out method to identify breakpoints and the Ministry of winding down its connected and insulated qualified to use. If your business is a buy and sell or something, you might need motors can be risky and dangerous.
4, the cage can be broken rotor cage welding, cold-connection of a repair or exchange.

bike motor variable speed control method of pole pairs is used to change the wiring to the stator windings to change the cage motor stator pole pairs to achieve speed control purposes, the following features:

1, with a hard mechanical properties, good stability;

2, non-slip loss, high efficiency;

3, the wiring is simple, easy to control, low prices;

4, class speed, a larger differential, can not get smooth speed control;

5, with speed regulator, used in conjunction with electromagnetic slip clutch, to obtain a higher efficiency of smooth speed control characteristics.

This does not require stepless speed control method for the production of machinery, such as metal cutting machine tools, lifts, lifting equipment, fans and pumps.

1, hub motor rotor of the stepper motor acceleration is slower than the rotating magnetic field, that is lower than the phase velocity change arising. This is because the lack of input electrical power, generated in the stepper motor torque can not make synchronous rotor speed to follow the stator magnetic field rotation rate, causing loss of step. And any high frequency than when the frequency is bound to work out of step. This illustrates the step-step motor drag is not enough. Once the reduced load, or increase the winding excitation current, it is possible to overcome the loss of step.

2, hub motor rotor speed is higher than the average of the average rotation speed of the stator magnetic field. Then the stator excitation power for longer periods, than the time required for the rotor step further, the rotor step process to get too much energy, resulting in pediment and the backlash of the swing oscillations. When severe enough to cause oscillation of step.

1, bldc motor under the control of the electric pulse can quickly start, rotating, and stopped and in a wide range of the speed control;

2, high precision, which requires a small amount of displacement corresponding to the pulse and to accurately and uniformly. This requires bldc motor small step, step, high precision, not losing steps or overshoot;

3, the action fast. That not only start, stop, fast reverse, and continuous high-speed operation in order to improve labor productivity;

4, the output torque can be directly driven load.