Brushless starter is not only the traditional wound rotor motor to get rid of a large and complex starting system, but also to solve the eddy current loss, leakage reactance, the starter heat a few of the most important issues. The starter is to install a pressure-relief device for synchronous operation of the motor rotor, motor speed and inertia effect, set the vacuum short tap, the shorting switch internal vacuum interrupter design, to eliminate from climbing electric starter caused burning phenomenon occurred. When the motor reaches the rated speed, without the use of the starter, the the shorted device will coil winding automatic disconnect, not only saves energy, but not heat coil winding to ensure the stable operation of the starter. Its advantages are: remove the slip ring, carbon brushes, brush box and short-circuit ring, remove the secondary loop systems in the frequency sensitive rheostat, AC contactors, time relays and other components, in the brushless motor loop operation based on the real to maintain the original operational characteristics of the motor, which prolong the life of the motor at the same time, also to ensure that the service life of the starter itself. Controlled brushless vacuum motor starter is bound to excellent starting performance, low price, power supply and load adaptive capacity, small size, energy efficiency and running easy maintenance, etc., to obtain a wider range of applications. Works: The working principle of the brushless starter motor is in the starting process, its resistance is a variable that can increase or decrease with the motor rotor current frequency is proportional to the size of the cases, the starter by the coil winding, the inner and outer core, front and rear yoke plate parts of the sleeve, short tap a circular reactor, the starter is mounted on the motor shaft, the motor during starting, the rotor current frequency fz is reduced with the rotor speed increases relationship rotor speed from 0 to ne, the rotor current frequency from 50Hz to smoothly down to 1 Hz, the iron loss by the maximum displacement of the starter to the minimum, equivalent to the rotor circuit of the external resistor, from the maximum displacement to a minimum, it can automatically with the change in frequency of the rotor for smooth adjustment. When the motor speed is close to the rated speed, short tap inertia force the starter automatically shorted, does not require any auxiliary electrical components, a good solution to the loss of the rotor temperature rise, the load current relatively high due to all the implications. The scope and technical parameters: Where the original resistance starter, reactors, frequency sensitive rheostat, liquid rheostat starters, soft starter starter JR JZR, YR, YZR three-phase wound rotor AC induction motor (variable speed, equipped with a camera except) can be selected and controlled brushless the vacuum motor starters "to replacement, with motor capacity 15-125KW. Drag equipment such as ball mill, crusher, fans, air compressors, pumps, conveyors, rubber mixing machine, hypoxia machine, mill regardless of the positive, occasionally with frequent start will not affect.