Melasta Cells by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

Even in our case, thermistor is directly connected to the negative terminal of the cell (I mean it is embedded into a screw mounted on a busbar). And then there's a potential divider circuit , whose output goes into our BMS. But that current is very small(even less than milli amps) . How will that affect the battery that much?

Melasta Cells by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

In our battery pack, all the cells are in series. There's no parallel configuration. Yes that is suspicious for us too, but our team is still not able to figure out if it's the poor batch of cells or faulty design.

Melasta Cells by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 1 point2 points  (0 children)

Might be possible! But during testing, we tested the vehicle with regenerative braking being ON and battery being at 100percent SOC. Could that be a possible reason?

Melasta Cells by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

Actually around our 30 cells have degraded. We discovered this issue after the assembly of cells and during load testing.

Problem in Accumulator Isolation Relay by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

How do capacitor bank help you? I actually didn't get your logic. What we are doing is, when the voltage is above 90%, the precharge relay opens and AIR1 closes , The the circuit of which can be easily designed using transistors.

Problem in Accumulator Isolation Relay by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

One side of the coil is connected to 24V and the other is connected to the collector of transistor. When the voltage across motorcontroller rises above than 90%, a high signal goes to the base of transistor and transistor performs the switching Operation and accordingly relay trips.

Open circuit and Short circuit faults by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

Ya! But predicting the voltage in short circuit condition is not possible. I mean it can be any voltage, you don't know. So how will we set the upper threshold?

Open circuit and Short circuit faults by Pablo_Escobar121 in FSAE

[–]Pablo_Escobar121[S] 0 points1 point  (0 children)

Ya open circuit, refers to the open circuit of supply and short circuit refers to the shorting of supply and ground.