With the introduction of semiconductor electronics, vacuum tube rectifiers became obsolete, except for some enthusiasts of vacuum tube audio equipment. The first vacuum tube diodes designed for rectifier application in power supply circuits were introduced in April 1915 by Saul Dushman of General Electric. More complex circuitry that performs the opposite function, that is converting DC to AC, is called an inverter.īefore the development of silicon semiconductor rectifiers, vacuum tube thermionic diodes and copper oxide- or selenium-based metal rectifier stacks were used. In these applications the output of the rectifier is smoothed by an electronic filter, which may be a capacitor, choke, or set of capacitors, chokes and resistors, possibly followed by a voltage regulator to produce a steady voltage. Many applications of rectifiers, such as power supplies for radio, television and computer equipment, require a steady constant DC voltage (as would be produced by a battery). In gas heating systems flame rectification is used to detect presence of a flame.ĭepending on the type of alternating current supply and the arrangement of the rectifier circuit, the output voltage may require additional smoothing to produce a uniform steady voltage. As noted, rectifiers can serve as detectors of radio signals. Rectification may serve in roles other than to generate direct current for use as a source of power. Rectifiers have many uses, but are often found serving as components of DC power supplies and high-voltage direct current power transmission systems. Early radio receivers, called crystal radios, used a " cat's whisker" of fine wire pressing on a crystal of galena (lead sulfide) to serve as a point-contact rectifier or "crystal detector". Historically, even synchronous electromechanical switches and motor-generator sets have been used. Physically, rectifiers take a number of forms, including vacuum tube diodes, wet chemical cells, mercury-arc valves, stacks of copper and selenium oxide plates, semiconductor diodes, silicon-controlled rectifiers and other silicon-based semiconductor switches. The process is known as rectification, since it "straightens" the direction of current. The reverse operation (converting DC to AC) is performed by an inverter. Input amplitude is 1/2 peak-to-peak, or rms.A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. (Unfortunately, the additional computation will cause the controls to become less responsive.)Īn input amplitude control is provided for convenience. While this improves matters considerably, one should increase the parameter in order to obtain more accurate ripple amplitude calculation for large inductance values. We attempt to remove the ringing using the Fourier transform. For large inductance values, transient low-frequency "ringing" causes difficulties in the computation of the ripple amplitude. This is done by sampling over the last several computed cycles. Ripple amplitude (rms) is computed and reported as a percentage of the mean output voltage. The rectifier provides half-wave rectification we can mimic full-wave rectification by using a full-wave rectified input voltage. The voltage-current characteristic of the rectifier (the function in the program) is typical of a solid-state diode however, the parameter allows the inclusion of significant internal resistance typical of a vacuum-tube rectifier. We have in mind the high-voltage, low-current application in vacuum-tube audio amplifiers. The plotted output voltage is computed by solving the system of three differential equations from applying Kirchhoff’s voltage law to each of the three loops of the circuit.
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