Nix Product Manual |
Product Description
INGENIA | 01/22/2019
19
For most systems where the cycle time is shorter than 3 Ï„ (thermal time constant) the equivalent current can be
calculated as the quadratic mean of the current during the full cycle. The load cycle can be simplified as different
constant currents during some times:
Where:
T
is the full cycle period.
I
1
is the current during t
1
I
2
is the current during t
2
I
n
is the current during t
n
4.4.4 System temperature
Next thermal image shows an example of the heat distribution in a NIX-10/48-y-z. This test has been performed
without cold plate at maximum load and air temperature in a 3 phase application.
The drive is getting hot even at 0 current!
This is normal. Nix power stage includes high power MOSFET transistors which have parasitic
capacitances. Switching them fast means charging and discharging those capacitors thousands of times
per second which results in power losses and temperature increase even at 0 current!
Recommendation: when motor is off, exit motor enable mode which will switch off the power stage.
