A solution of a rectifier filter circuit with a capacitive input

Abstract

<p>In the last fifteen years a number of analyses of the full-wave rectifier circuit with a condenser-input filter have been made, and several of these analyses have presented characteristic curves which could be used in the design of the circuits. These analyses used rather severe assumptions in most cases, and the characteristics were applicable only over a small range of parameters. The present investigation was started with the idea of using more liberal assumptions and producing characteristics suitable for design work that could be used from open-circuited to short-circuited loads and with all values of filter inductances in practical use;In the solution of the circuit equations, the usual method of differential equations was tried and abandoned, and a new steady-state operational calculus developed for this type of problem was tried and was successful in solving the circuit equations. This solution was made for various values of the parameters and was extended to the cases where one or more of the parameters became zero or infinitely large;The boundary between the cut-off and the non-cut-off types of operation was obtained, and the solution of the non-cut-off case was made. The point of filter resonance was approached very closely, but difficulties with the solution prevented further investigation of the resonance condition;Characteristic curves and equations suitable for use in design and covering the range from open-circuited to short-circuited loads and from very large filter inductances to such small ones that filter resonance almost occurs, were constructed. A method of using these characteristics in the actual design of rectifier and filter circuits was also presented;Experimental results of the operation of an actual circuit were presented and found to agree very closely with the calculated results particularly when correction is made for the resistance of the tube and filter inductance. The correction can also be applied in the design work. Several possible future extensions to the present analysis and characteristics were also suggested.</p>