The 4 quadrants of working for an ATV71 drive corresponds to the graph where the speed is the X-axis and the torque is the Y-axis.
When the sign of torque and speed are the same, the quadrant is motor. It means that the AC drive give the energy to the motor. In these quadrants, it is easy to work correctly.
When the sign of torque and speed are different, the quadrant is generator. It means that the motor give the energy to AC drive. In these quadrants, this energy must be dissipated to work correctly because it makes the dc bus voltage increase.
One possibility is to dissipate the generator energy into a braking resistor.
The other possibility is to regenerate this energy into the main supply.
We have 2 solutions for that: the Network Braking Unit and the Active Front End.
With these options, the ATV71 can works in the 4 quadrants.
When the sign of torque and speed are the same, the quadrant is motor. It means that the AC drive give the energy to the motor. In these quadrants, it is easy to work correctly.
When the sign of torque and speed are different, the quadrant is generator. It means that the motor give the energy to AC drive. In these quadrants, this energy must be dissipated to work correctly because it makes the dc bus voltage increase.
One possibility is to dissipate the generator energy into a braking resistor.
The other possibility is to regenerate this energy into the main supply.
We have 2 solutions for that: the Network Braking Unit and the Active Front End.
With these options, the ATV71 can works in the 4 quadrants.