Sevcon Gen4, Applications Reference Manual, Page: 78 / 123

Doc. # 177/52701
Rev3
6-8
The controller may refuse to enter pre-operational if part of the system is active: for example, if
the vehicle is being driven. The request is logged in the EEPROM however, so if power is
recycled th
e system won’t enter operational and remains in pre-operational after powering up.
The NMT state can be read at 5110
h
where 05 = operational and 7F = pre-operational.
Motor characterization
Ensure you have completed the CANopen network setup process.
Determining motor parameters
To provide optimum motor performance Gen4 needs the basic motor information normally found
on the name plate as well as the following information:

A value for each of the electrical parameters of the induction motor as shown in Figure 21.

The magnetic saturation characteristics of the motor in the constant power and high speed
regions.

Current and speed control gains.
Figure 21 AC motor single-phase equivalent circuit
To determine these parameters use one of the following methods:
1. Ask the motor manufacturer to provide the data and enter it in the Object Dictionary at 4640
h
and 4641
h
. Also enter encoder data at 4630
h
and 6090
h
and motor maps at 4610
h
to 4615
h
.
The motor maps are dependant on the motor type:
Motor Type Map Object Usage
PMAC
4610
h
Motor flux map showing torque versus magnetising current.
4611
h
Motor power limit map showing maximum torque versus
speed.
4612
h
Voltage cutback map showing voltage versus torque reduction
factor.
4615
h
Second motor power limit map. Overrides map in 4611
h
based
on trigger defined in 4652
h
.
Flux Vector
4610
h
Motor flux map showing torque versus magnetising current.
4611
h
Motor power limit map showing maximum torque versus
speed.
4612
h
Voltage cutback map showing voltage versus torque reduction
factor.