CANBus : EPIC module (746)

[dernotte]

Let's start a different thread for EPIC Module.
EPIC module seems very interresting. I found that PID DD08 and DD09 to be speed , but does not give always the exact same value. Because it is the front Inverter, I guess this is the speed for the two front wheels, and I will find the speeds for the 2 rear wheels on the EPICB module.
PID 494C give a positive value when the motor takes energy to move on, and negative value when in regen mode.
PID 4950 seems linked to the speed, move with the same shape, but completely different value compared to the speed.

[dernotte]

PID 494C seems to be the Kw/100km, with the formula (signed(A)*256+B)/10

[kermit68]

Let's start a different thread for EPIC Module.
EPIC module seems very interresting. I found that PID DD08 and DD09 to be speed , but does not give always the exact same value. Because it is the front Inverter, I guess this is the speed for the two front wheels, and I will find the speeds for the 2 rear wheels on the EPICB module.
PID 494C give a positive value when the motor takes energy to move on, and negative value when in regen mode.
PID 4950 seems linked to the speed, move with the same shape, but completely different value compared to the speed.

on 726 DD09 is speed but I think it's the real speed, i.e. -3% of the speed displayed on the dashboard.

[dernotte]

I still don't know what are the PID 494B, 4952, 4953 but they seem to be corrolated.

[dernotte]

What we are looking for in EPIC :

High Voltage (HV) 3-phase Alternating Current (AC) cable from the front Electric Power Inverter Converter (EPIC) to the front Electric Drive Unit (EDU)

HV Direct Current (DC) cable from the EV battery to the front EPIC

The Powertrain Contol Module (PCM) controls the front and rear Electric Power Inverter Converters (EPICs) which control the relevant front and rear Electric Drive Unit (EDU). The front and rear EDUs provide the power to move the vehicle forwards and backwards. The front and rear EDUs also provide regenerative braking.

The front and rear EPICs receive messages from the PCM and change the operation of the relevant EDU between a motor and a generator as required.
When the EDU operates as a motor, the EPIC takes Direct Current (DC) power from the Electric Vehicle (EV) battery and converts the High Voltage (HV) DC to HV 3-phase Alternating Current (AC). The EPIC controls the HV 3-phases to deliver the required power to the EDU.
When the EDU uses regenerative braking, it operates as a generator to provide regenerative braking. The EPIC converts the HV AC from the EDU into HV DC to charge the EV battery.

The PCM controls the electric drive temperature control system to cool the front and rear EPICs.

[dernotte]

Engine data

The vehicle has one traction inverter on each of the front and rear drive units. The self-contained design allows use in various vehicle models and different powertrain applications. The three-phase architecture consists of a Jaguar Land Rover specific power module, a DC link capacitor, a gate drive Printed Circuit Board (PCB), a control PCB and a low voltage interface PCB. All elements are housed in a liquid-cooled die-cast aluminium housing. In the I-Pace, the traction inverter can provide a peak three-phase current of 550 A for 10 s and operates without phase current limitation in the range of 290 to 450 V at the DC input.

[dernotte]

Not sure at all, but

PID 494D could be voltage from the battery : (value / 32). This value slowly decrease, as I drive.
PID 4950 could be current generated by the inverter : (value / 16)
PID 4953 could be the internal Inverter temperature : formula ??? (value / 32). This value keep growing as I drive, and then slowly go down when I stop.
PID 4952 could be voltage generated by the inverter : (value / 4)

[dernotte]

I found this morning that initial value for 494B, 4952, 4953, for a full night resting in the driveway, with ambiant temperature at -7c, is negative (2 bytes, value in the 65000 range), and these values ramped up as I drive. Could it be a coolant temp value ?
The initial value was around -420, so formula should be (value / 60) to be -7 ???

The other PID I can't find the description is 4951. The value is around 12300 when the car is off, and climb to around 15000 (14900-15300), and keep changing in that range while I drive.

[dernotte]

Look at these 4 different graphs, the red line (4952) ramp up and every time it reaches "1000", it cools down, and then it can go higher. I am sure this is a temperature.

[dernotte]

The only good description I can give to PID 4951 is the startup battery : 15v when the car is on, and 12v when the car is off.