2.4 Electric Parameters

Main power supply input: DC 24V ~ 48V

Driver power supply input: 12V

The phase current is constrained by the rated current ${\displaystyle I_{rated}}$, which defines the maximum current that can be endured by the driver board.

${\displaystyle I_{rated}^{peak}=30A}$

${\displaystyle I_{rated}^{RMS}=15A}$

A current bigger than ${\displaystyle I_{rated}}$ can cause damage on the driver board.

The DC bus current is constrained by the over-current (OC) threshold ${\displaystyle I_{oc}}$.

${\displaystyle I_{oc}}$ is the smallest transient DC bus current which triggers the over-current event on the control board. ${\displaystyle I_{oc}}$ depends on the shunt resistance on the driver board and the OC circuit on the control board. The control board triggers an OC event if the regulated signal is not less than ${\displaystyle \frac{1}{2}AVDD}$; and the regulated signal is ${\displaystyle I_{oc}\times R_{shunt}^{bus}\times G^{bus}}$, therefore:

${\displaystyle I_{oc}=\frac{AVDD}{2\times R_{shunt}^{phase}\times G^{phase}}}$.

Where,

${\displaystyle R_{shunt}^{bus}}$ is the shunt resistance for the DC bus current

${\displaystyle G^{bus}}$ is the regulating circuit’s gain for the DC bus current sample signal

AVDD is the analog power supply voltage for the ADC

${\displaystyle G^{bus}}$ and AVDD are fixed for a certain control board, while ${\displaystyle R_{shunt}^{bus}}$ can be modified by the user. In other words, ${\displaystyle I_{oc}}$ can be defined by the user by selecting ${\displaystyle R_{shunt}^{bus}}$.

${\displaystyle R_{shunt}^{bus}}$is recommended to be selected in such a manner that ${\displaystyle I_{oc}}$ is not bigger than ${\displaystyle I_{rated}}$.