Siemens Eupec, Manual

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Cell Control Board - 10000432 MicroHarmony Cell Sizes 40 - 260A Manual
5-4 19001467: Version 1.0
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5
5.4.3 OOS Detection/Latch
Out of Saturation is detected by monitoring Vce of the IGBT. Each fault feedback from the gate drive channels goes
through a two-shot circuit that verifies that two consecutive OOS (Out-of SAT) faults occur before the drive trips.
This provides extra immunity from false OOS faults. OOS is annunciated within 10 to 14
μ
S after second OOS
pulse.
5.4.4 Bus Voltage Sensing and Protection
Three differential amplifiers are used to m to - bus, +2/3 to - bus, and +1/3 to - bus. These analog signals are
filtered and scaled 1:-100, named P1DET, P2DET, and P3DET.
1. Capacitor Voltage Monitoring
P1DET and P2DET are summed and scaled to produce a 1/3 bus voltage signal divided by 100. Likewise,
P2DET and P3DET are summed and scaled, and P3DET and agnd are summed and scaled. Each of these 3
signals are compared to a fixed 10VDC reference to a diode AND circuit. In the event that any 1 signal
exceeds the scaled threshold (430V for 400V caps and 484V for 450V caps), then VCAP_OK annunciates a
“Cap share Fault” and trips the cell. Three select resistors are used for trip point scaling.
2. Bus Voltage Monitoring
P1DET is filtered and scaled for Vbus/255 and compared to a fixed 10V reference that is scaled for the
appropriate over voltage trip point. In the event that the bus voltage exceeds the scaled threshold, VDC_HIL
annunciates a “DC Bus over voltage Fault” and trips the cell. (630V cell trips at 1084VDC, 690V cell trips
at 1200V, 750V cell trips at 1300V). A solder blob jumper is used for trip point scaling.
The filtered and scaled P1DET (Vbus/255) is also compared to a scaled 10V reference for low bus fault
annunciation. If the DC bus drops below 475VDC, VDC_LOWL will annunciate a “Low Bus Fault” and
trip the cell.
The filtered and scaled P1DET (Vbus/255) is also compared to a scaled 10V reference for voltage available
fault annunciation. If the DC bus drops below 300VDC, POWER_OK will annunciate a “Control Power
Fault” and trip the cell. When the bus is below 300VDC, the CCB SMPS may not operate properly and must
shut down.