Motor startup mode

Include:motor startup mode,auto voltage reducing total pressure direct start starting,y-delta

starting,soft starter,inverter.Total pressure directly starting:At both capacity and load of power

grid allows total pressure directly under the condition of starting,can consider to use the direct

starting.Advantage is that control is convenient,simple maintenance,and more economic.Mainly used in ac geared motor small power motor starting from saving energy point of view,should not be greater than 11 kw motor by this method.Auto voltage reducing starting:use autotransformer tapped the reduced pressure,can adapt to the needs of different load starting,and can get a bigger starting torque,is a kind of is often used to starting decompression of the large capacity motor starting.Its the biggest advantage is

starting torque is bigger,when the tap at 80%,starting torque can be up to 64% of direct starting.And can adjust the starting torque by tapping.Are still widely used.

Y-delta starting:for normal operation of the stator winding of delta connection of squirrel-cage asynchronous motor,if at the time of starting the stator windings into star,waiting for start to end to connect into a triangle,can reduce the starting current,to reduce its impact on the grid.Such starting way is called star triangle decompression starting,or simply the star delta starter (y - delta starter).Using star delta starter,starting current is only according to the delta connection directly when starting a third of the original.If direct starting when the starting current to 6~7 meter,ie in star triangle is

starting,the starting current is 2~2.3 gasoline generator spare parts times.This means using star delta starter,starting torque is reduced to the original starting directly based on the delta connection when a third.Suitable for the occasion of no load or light load starting.And compared with any other decompression starter,its structure is the most simple,the price is the cheapest.In addition,a further advantage of star triangle starting way,namely when the load is lighter,can let the motor run in y connection.

At this point,the rated torque and load can match,this can make the motor efficiency is improved,and save the electricity consumption.Soft starter:this is the phase shift voltage regulating principle of SCR is used to realize the regulating of the motor starting,it is mainly used for motor starting

control,starting effect Motor vehicleis good but the cost is higher.By using thyristor,thyristor harmonic interference is larger at work,have a certain influence on power grid.Additional power fluctuations will also affect the thyristor conduction,especially how thyristor devices in the same power network.So the thyristor failure rate is higher,because involving power electronic

technology,therefore,taller also to the requirement of maintenance technicians.Inverter,inverter is

the highest technical content of modern motor control field,the most complete control function,the best control effect of motor control device,it is by changing the frequency of the power grid to adjust the rotation speed and torque of the motor.Because of involving power electronic technology,computer technology,so the cost is high,too high to the requirement of maintenance technicians,mainly used in need speed and the field of high speed control requirements.