Some of the US manufacturers show graphs of leakage current for some products. I don't recall which particular ones, so you will have to search around a bit.Ntip said:Is there some way to estimate the percentage the leakage current would increase based one either of these factors?
You have not specified the capacitor technology you will use. Are you using electrolytic capacitors?Ntip said:I am lookin designing balancing resistors for series capacitors and understand that I need to consider the leakage current from the capacitors. I am trying to determine factors that would case the insulation resistance to decrease over time so I can design around that.
I was thinking about electrolytic because it seems like I can get a high value capacitance pretty easily.Baluncore said:You have not specified the capacitor technology you will use. Are you using electrolytic capacitors?
I think of electrolytic capacitors as being more like living things that must be cared for, and that can chemically learn about operating voltages, or die in a hot environment. In many respects, other types of capacitors are more robust.
We discussed various aspects of resistive balancing for chains of capacitors in a recent thread.
https://www.physicsforums.com/threa...-my-high-voltage-circuit.994058/#post-6396764
Fixed ratio "broad band potential dividers" are an interesting subject.Ntip said:I actually had a question about the matching RC time constant part but I'll make another thread about that since this one is titled as insulation resistance.
The value of the balancing resistor can be calculated using the formula R = 1/(2πfC), where R is the resistance in ohms, f is the frequency in Hertz, and C is the capacitance in Farads. This formula takes into account the reactance of the capacitor and ensures that the resistor will balance the current flow in the circuit.
The value of the balancing resistor is affected by the frequency of the circuit, the capacitance of the capacitor, and the desired amount of current flow. Higher frequencies and larger capacitance values will require a lower resistance value to balance the current flow, while lower frequencies and smaller capacitance values will require a higher resistance value.
Ideally, a resistor with low inductance and low capacitance should be used for balancing series capacitors. This will minimize any unwanted effects on the circuit and ensure accurate balancing. A metal film or carbon composition resistor would be a good choice for this application.
If the balancing resistor is too small, it will not be able to effectively balance the current flow in the circuit. This can result in an uneven distribution of current and potentially damage the capacitors or other components in the circuit. It is important to calculate the appropriate resistance value to ensure proper balancing.
In most cases, it is necessary to use a balancing resistor for series capacitors. This is especially important in high frequency circuits where the reactance of the capacitor can significantly affect the current flow. However, in some low frequency applications, a balancing resistor may not be necessary if the capacitance values are small enough and the current flow is well controlled.