Энергокомплект

AVR AUTOMATIC FIELD CONTROL FOR CAGE SYNCHRONOUS BRUSHLESS MOTORS

APPLICATION

AVR-ХХ-BR-QХD microprocessor automatic field control, produced by CC “Energocomplekt”, is designed for power supply by automatically adjustable current of field windings of a cage synchronous motor brushless exciter in all its operational modes. The control also carries out functions of control, protection and signaling about the field system condition.

STRUCTURE OF SYMBOLS

AVR	-XX	-BR	-QX	-D	-()
					type of climatic modification
					for motors
					for brushless field systems
					nominal current, A
					Capacity, MW
					automatic field control

AVR controls of a cabinet dedign, the notation for field control cabinet (“ECC cabinet”) is used.

PWM	-XK	-XX	-XX	-D	-()
					type of climatic modification
					for motors
					nominal voltage, V
					nominal current, A
					number of converting-regulating channels
					field control cabinet

     The control is produced in UHL climatic modification, accommodation category 4 in accordance with GOST 15150 and GOST 15543 with the following influencing factors:

     - ambient temperature from +1 up to +40 ⁰С;
     - height above sea level up to 3000 m;
     - relative humidity not more than 80% at temperature +25 ⁰С.
     - environment: non-explosive, not containing current-conducting dust in concentration reducing insulation level to impermissible limits.

Fig. 1. AVR-8-BR-Q1D automatic field control for cage synchronous motors.

OPERATING MODES

Field automatic control provides:

field automatic supply in sliding function at the cage synchronous motor start-up;

local or remote change of voltage setting with the speed of 0.5 % per second in the range from 80 up to 110% with relation to nominal voltage or reactive capacity;

maintenance of voltage set by the device on the stator outputs with accuracy not worse than 1% (with relation to the established static characteristic) or reactive capacity with accuracy not worse than 5%;

forcing field current up to the preset values on the frequency rate at reduction of voltage on the stator outputs by 10-20% and more;

limiting field current on the double value of the rotor current;

limiting the duration of field forcing depending on its frequency rate;

clearing (unexciting) the motor field by clearing the brushless exciter field;

limiting the minimal field current to the value not allowing the motor switch to the mode of reactive capacity deep consumption and falling out of synchronization;

There is also a possibility of outputting through dry isolated contacts the following signals about the condition of the control and the activator:

automatic mode of the control operation;

manual mode of the control operation;

field system failure (breakdown of the rotating rectifier diode, breakdown of the control power transistor, field loss, increased voltage on the stator outputs).
Note: Permissible current through the relay contacts is 0.7 А at the direct current voltage 250 V.

BASIC SPECIFICATIONS

Name of the parameter	Value
Nominal rectified current, A	8
Nominal rectified voltage, V	75
Maximum rectified voltage, V	180
Overload duration by two-times current, sec	60
Nominal voltage of alternating current circuits (from additional winding), V	110…230
Nominal voltage of alternating current circuits, V	220
Power consumption on alternating current circuits, W, not more than, in nominal mode in forcing mode	450 3000
Nominal voltage on circuits of the stator voltage measurement, V	100
Nominal current on circuits of the stator current measurement, A	5
Power consumption from current and voltage measuring transformers, per phase, VA, not more than	1

The company carries out installation supervision, adjustment and testing of field systems, warranty and post-warranty service, modernization and repair of motor field systems in operation, maintenance personnel training and technical advisory services on equipment selection. Field systems equipment is delivered within 3 months from the date of contract execution and prepayment.