Regulator Board; 6: Vector Mode Regulation - Reliance electric GV3000/SE Instruction Manual

Vector Regulation Mode
The GV3000/SE is a digital AC controller using closed loop vector control (Refer to Figures 6-1a,b,c).
Vector control offers the same dynamic performance to an AC motor as that achieved with a DC motor.
Torque is constant across the motor's base speed range in both forward and reverse direction. The
controller, under microprocessor system control, uses two control loops, speed and torque, to obtain
vector performance.
Under the speed control loop, the speed reference (requested speed) can be an internal or an external
source. The speed loop's feedback is provided by an encoder attached to the motor's shaft. The actual
speed of the motor being calculated as the rate of change of position from the encoder. An error signal
derived from the difference between the requested and actual motor speed is implemented digitally
(speed controller) to generate the torque command signal for the controller's torque control loop. The
torque, in this case, will vary to maintain the motor at it's requested speed.
Under torque control loop, the torque reference (requested torque) accepts a torque signal from the
speed loop or from an selected torque reference. The torque control requires calculations and execution
of motor equations based on given motor parameters to develop slip. The motor parameters required
are magnetizing current (No load phase currents), motor nameplate data, and relative position of the
rotor with time. Motor magnetizing currents are measured internally by the GV3000/SE controller while
the rotor relative position is performed using an encoder. The torque control then provides information
for microprocessor system to generate the switching of the IPM's (Intelligent transistor Power Modules)
which, in turn, generates the motor phase voltages (PWM).
When the controller is configured for torque, it should be recognized that since only torque, not speed, is
being regulated that an overspeed condition can result given certain motor/load conditions. A value of
thirty percent (30%) over Maximum Speed (P.004) will cause an overspeed 'OSP' fault in the controller.
The inverter consists basically of two sections, the power section and the regulator section:
In the power module, the line voltage is converted into a DC voltage from which a variable output voltage
with variable frequency is produced by means of transistor modules. The GV3000 Power modules are
described in manual 49'1327 with block wiring diagrams presented.
In the regulator section, the control of the Output Power Modules required for this purpose is produced
and monitored. The regulator hardware section can be split into three different modules:
Microprocessors perform in Vector mode the speed, field and the Vector Torque control.
General parameter P.048 provides selection of regulation mode to enable Vector regulation.
Refer to Section 4 for
Refer to Section 8 for
Section 4 for
Section 3 for
The following parameters with this warning sign are safety relevant and must be
adjusted by a qualified person who understands the significance of setting them
accurately. Failure to observe this precaution could result in bodily injury.
49'1329 e
6 - VECTOR REGULATION MODE

Regulator board

PIS Power Interface and Supply card
Keypad
Description of parameter types: 'Configurable' and 'Tunable'.
- Parameter Lists Overview,
- General Parameters description,
- Parameter verification and programming, and password entry.
GV3000/SE 6 - 1