Descriptions Of The Control Program; Contents Of Control; Motor Start/Stop; A/D Converter - Renesas RA6T2 Application Note

Sensorless vector control for permanent magnetic
synchronous motor - 1shunt current detection

3. Descriptions of the control program

The target software of this application note is explained here.

3.1 Contents of control

3.1.1 Motor start/stop

Starting and stopping of the motor are controlled by input from 'Renesas Motor Workbench' or SW1.
A general-purpose port is assigned to SW1 and based upon its level the motor operation is controlled.
"High" level  Motor Start
"Low" level  Motor Stop

3.1.2 A/D Converter

(1) Motor rotation speed reference
The rotation speed command value of the motor is determined from the input from 'Renesas Motor
Workbench' or the output value (analog value) of VR1. Rotation speed command value from VR1 is
measured as shown in the table below.
Table 3-1 Conversion Ratio of the Rotation Speed Reference
Item Conversion ratio (reference: A/D conversion value)
CW
Rotation speed
reference
CCW
(2) Inverter bus voltage
Inverter bus voltage is measured as shown in the table below. It is used for calculation of modulation rate
and detection of overvoltage and low voltage (PWM stops in case of abnormality).
Table 3-2 Inverter Bus Voltage Conversion Ratio
Item Conversion ratio (Inverter bus voltage: A/D conversion value)
Inverter bus
0 [V] to 73.26 [V]: 0000H to 0FFFH
voltage
(3) Phase current with 1shunt resitance
The phase currents are measured as shown in Table 3-3 and used for vector control.
Table 3-3 Conversion Ratio of Phase Current
Item
Phase current
R01AN6840EJ0100 Rev.1.00
May 23, 2023
0 rpm to 2400 rpm: 0800H to 0FFFH
0 rpm to 2400 rpm: 07FFH to 0000H
Conversion ratio (Phase current: A/D conversion value)
-8.25 [A] to 8.25 [A]: 0000H to 0FFFH
Current = (3.3V-1.65V)/(0.01Ohm＊20) =8.25A
For Renesas Flexible Motor Control Series
(Note)
Channel
AN008
Channel
AN006
Channel
AN004
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