PRODUCTS

Description:

Nowadays, more and more super large motors are used in the various industries. Such as ball mills in mines, centrifugal pumps in the petrochemical complex, axial flow compressor in the steel companies, and pumped storage Hydropower plants/PSH;

How to start those large motors steadily under different rough conditions,soft starter based on SCR-controlled transformer is the answer.

Application Industries:

• Steel & mines;

• Petrochemical;

• Oil industry;

• Pumped-storage Hydropower plants

• Etc 

Working Principle：

QF2 is the motor running panel. QF1 is the motor starting panel.

One three phase transformer KT, its primary site of transformer is connected to the HV mote in serial, and its secondary side is connected to SCR. The turn-on angle of the thyristor is controlled by PLC. Change the angle, the motor stator’s voltage applied will change accordingly from zero to its rated voltage. While the motor reaches its rated speed, turn off QF1, and turn on QF2.

Motor started by transformer soft starter

Main Features:

• Very high reliability with 100% start-up success. It is different from reactor starter and  VFD reactor. It is very important for key accounts;

• Less power losses and temperature rise, suitable for frequent starting. Once 6 starting trials are failed, only 10 minutes break, you can restart your motor. For reactor starter, a few hours is waiting for restarting;

• Starting voltage and current could be increased since zero continuously, therefore, no overvoltage surge, no torque impulse. Compared to reactor starter and auto-transformer starter, It is soft starting;

• Compared to VFD starter, transformer soft starter,

  Less harmonic waves, THD less than 4%; For VFD starters, 6-19%;

  Less starting time, less than 1 minute usually; For VFD starters, 5 minutes for 300MW PSH sets;

  High voltage VFD is cooled by water. The cooled system is complicated, and its maintenance;

  Bigger footprint is required for VFD starter;

  High cost for total cost of ownership for VFD starter

• Large starting capacity up to 50000KW, even bigger;

• Module design, with easy of repair and extension;

• Controlled by PLC and current/voltage measure and feedback, transformer soft starter could match motor start-up curve properly;

• One device could be used to started two even three motors in sequence to save your investment;

• Suitable for harsh working environments;

Main Specifications:

• The line voltage range: 6-15KV;

• Motor capacity range: 5000-50000KW;

• Starting current range: 0.5-4.0 Ie , continuously adjustable 

• Starting voltage range:5-95% Un, continuously adjustable;

• Starting time: 4-60 seconds, adjustable;

• Continuous starting up to 6 times, and the break time is 10 minutes for restarting;

• Protections

  Over and under voltage, Phase open;

  Over and under current, unbalance;

  Start timeout;

• Ambient temperature:0℃-40℃;

• RH:90% at 25℃, No dew;

• Altitude: 1500 meter

Ordering Information:

Designed to order, brand new or update, repair & replacement;

Reactive compensation device could be provided together with transformer soft starter providing the shortage of the local line capacity;

Field commissioning & training is available.