There isn't a formula for the choke in a CLC filter, unless you decide exactly how much ripple attenuation you want or which subsonic resonance frequencies to avoid.
I will add a little to the fray.
The choke is part of the overall big picture of the power supply filter. We often use vacuum tube rectifiers. The vacuum tube rectifier cut sheets list a maximum capacitance at the output of the tube rectifier. For me that 1st capacitor is a nominal 47uf then followed by that 6 Hy Triad choke (chosen because of price). Then you can follow the choke by whatever number of C R poles you like or a monster value capacitor of your choosing.
The choke protects the vacuum tube rectifier from over amping plus adds some inductive filtering without adding too much resistive nature impedance to the power supply.
DT
The choke is part of the overall big picture of the power supply filter. We often use vacuum tube rectifiers. The vacuum tube rectifier cut sheets list a maximum capacitance at the output of the tube rectifier. For me that 1st capacitor is a nominal 47uf then followed by that 6 Hy Triad choke (chosen because of price). Then you can follow the choke by whatever number of C R poles you like or a monster value capacitor of your choosing.
The choke protects the vacuum tube rectifier from over amping plus adds some inductive filtering without adding too much resistive nature impedance to the power supply.
DT
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way to go.......over here filter caps from discarded psu's are a "dime a dozen"......😀
Hello,
I just decided to do this choke calculation thing backwards. The process is one I developed as a kid; take it apart with a hammer to see how it works. The process has been refined stepwise over the years. I bought a couple of chokes to play with, from Surplusshack.com, including the one below. The plan is to assemble a power supply on the bench and perform the calculations in the link provided in post 23 by Tony. Odd thing the formula is the same as taught by Clyde Echols back in High School electronics class.
After testing for inductance and estimating current who knows it may be fun to beat them with a hammer. I might learn (we know the theory) to better apply a choke. Plus the choke(s) may be useful otherwise.
UNUSED DEL-TRAN HEAVY INDUCTOR CHOKE - Surplus Shed
DT
I just decided to do this choke calculation thing backwards. The process is one I developed as a kid; take it apart with a hammer to see how it works. The process has been refined stepwise over the years. I bought a couple of chokes to play with, from Surplusshack.com, including the one below. The plan is to assemble a power supply on the bench and perform the calculations in the link provided in post 23 by Tony. Odd thing the formula is the same as taught by Clyde Echols back in High School electronics class.
After testing for inductance and estimating current who knows it may be fun to beat them with a hammer. I might learn (we know the theory) to better apply a choke. Plus the choke(s) may be useful otherwise.
UNUSED DEL-TRAN HEAVY INDUCTOR CHOKE - Surplus Shed
DT
Or more simple: Build a LC oscillator with a know capacity and adjust the frequency until you get a resonance peak on the oscilloscope. Then use thomsons equation:
Used in series resonance, you don't get any problems with the DC-resistance.
Used in series resonance, you don't get any problems with the DC-resistance.
And if the choke is too small for the load resistance. the voltage across it can contain oscillatory spikes up to several kV. And that is why choke input supplies usually have a resistor across the capacitor - to ensure that enough current is drawn to prevent spiking if the main load is disconnected.
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