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#### wannabetech

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Im trying to figure out what the series-parallel capacitor configuration in a substation would be used for. Example: Each phase of the substation bus has 3 capacitor banks in series with each other. Each capacitor bank has 10 capacitors in parallel. Now each bank is going to have a high capacitance since the caps in the bank are in parallel, but then we have 3 banks which are in series with each other which is going to decrease the overall capacitance. I don't see the point in having high capacitance banks and then lowering that capacitance by connecting them in series.

#### gpop

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Im trying to figure out what the series-parallel capacitor configuration in a substation would be used for. Example: Each phase of the substation bus has 3 capacitor banks in series with each other. Each capacitor bank has 10 capacitors in parallel. Now each bank is going to have a high capacitance since the caps in the bank are in parallel, but then we have 3 banks which are in series with each other which is going to decrease the overall capacitance. I don't see the point in having high capacitance banks and then lowering that capacitance by connecting them in series.
Never seen caps in series. A important note you seem to be missing is the switch's that are adding or removing caps. (unless this is something ive never seen before). So its not 10 in parallel but a option to have up to 10 caps on line.

#### wannabetech

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Never seen caps in series. A important note you seem to be missing is the switch's that are adding or removing caps. (unless this is something ive never seen before). So its not 10 in parallel but a option to have up to 10 caps on line.
The cap banks themselves are not switched individually. There are 3 sets of 10 caps. the 10 are connected in parallel and then the 3 sets are connected in series, basically like this:

-----C------C------C----

C represents a set. Each C is made up of 10 paralleled caps. (this is only representing one phase, so total there are 9 sets of 10). There is one main breaker that will tie all of these capacitors to the power system for power factor correction with high inductive loads causing voltage sag. So the system will see a sag in voltage and say I need some capacitance now, close the breaker tying in the capacitor bank to the system and now all of the capacitors are tied in

#### dmxtothemax

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Capacitors are normally put in series arrangements for voltage rating

so three 100v caps would become 1 x 300v cap

#### MikeFL

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test post
please ignore

update: test complete.
continue to ignore

#### dronai

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Im trying to figure out what the series-parallel capacitor configuration in a substation would be used for. Example: Each phase of the substation bus has 3 capacitor banks in series with each other. Each capacitor bank has 10 capacitors in parallel. Now each bank is going to have a high capacitance since the caps in the bank are in parallel, but then we have 3 banks which are in series with each other which is going to decrease the overall capacitance. I don't see the point in having high capacitance banks and then lowering that capacitance by connecting them in series.
lain: Did you already finish your Transformer book ?

#### micromind

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Capacitors are normally put in series arrangements for voltage rating

so three 100v caps would become 1 x 300v cap
This is pretty normal for VFDs.

#### gpop

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What voltage do you have at the substation?

#### wannabetech

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