Rectifier voltage - it's not exactly the right combination of words related to the schemes in various rectifier. The latter include, first of all, the diodes. Previously used valve tube of various designs.
From the history of the question
Straighten succeed only current, but if we apply the word to stress the professional term will be understood. The electrons are able to move in both directions wire, depending on the potential difference. What is happening is called alternating current, alternating current direction. So that the electrons are constantly moving straight and not rolled up, the rectifier is required.
Hence, the definition is specified. Rectifier (voltage) of the current device is called, causing the electrons to move the chain in a single direction only. There is a difference between amateur and professional environment:
- Pupils at the school say that the line is called direct current. At the level of the class of physics is no division. Perhaps so as not to confuse the students.
- Professionals pulses of one polarity are already calling rectified voltage (current). In this light, a simple diode valve without anti-aliasing filter is considered to be a rectifier in the full sense of the word.
Thus, the phrase, the above mentioned, it is permissible to interpret differently. If you want to DC current as the battery, but from the power outlet, the desired device is supposed to be called:
- DC adapter.
- DC power supply.
- DC converter.
But rectifier. The latter refers to a cutting portion of the negative current and voltage. Subjected to processing both parameters emerging from Ohm's law for subcircuit. Pereozvucheny if at the chain ends without discontinuities present voltage, current will flow. The only exception to the rule gives a capacitor. In the traditional physical classroom is not considered at the mention of Ohm's law. But in high school taught that capacitance changes the phase shift between voltage and current.
Summarizing: direct rectifier rectifies two parameters, the current and voltage. In the first case there is a unidirectional motion of the electrons in the second - the gradient of the potential difference constant. Rectifying properties, as opposed to public opinion was originally discovered in semiconductors. Vacuum tubes invented much later as a result of research of Thomas Edison and others (see. Incandescent).
Opening on semiconductors made in 1874, Karl Ferdinand Braun shortly after the relocation to the new destination of the supervisor George Quincke. University did not find a suitable position, the discoverer of the rectification effect begins to teach at the high school. Extensive leisure Brown provides enough time for research activities, in the light comes first Work on artificial and natural oxides of copper, platinum, nickel silver, pyrite, chalcopyrite, galena.
Investigation of the tetrahedron of faded rock showed anisotropic properties found. Summing each of the faces of the silver wire 8, the scientist measured current using a multiplier (galvanometer). Voltage voltaic pile constantly checking back, remembering the sad experience of Georg Ohm. The requirement arose when scientists discovered nonlinearity conductivity metal-crystal. Today the half parabola see on any current-voltage characteristic of the diode. Actually, it showed rectifying properties of minerals. We can only regret that the translation work on the Russian language is not available, and English is only available for a large sum of money, but persistent readers let conquer German!
tube rectifiers
According to statistics at the time of the mid-70s of all energy produced in the USSR, about a quarter were required to convert to DC. For actions needed cheap and high-quality devices than Stalin factories offered to consumers.
Already eating away were numerous technical solutions, but most of the electrical circuits implemented on lamps: diodes, transistors, and so forth. The figure shows the stagnant options rectifiers, taken from the book Mazel KB edition 1951. The undoubted advantage of the scheme is recognized as generally understood. Description of the half-wave rectifier tube:
- Alternating current is fed to a transformer with two secondary windings, one designed entirely for heating the cathode (in the figure - to the right, the arc).
- The arrow with the current direction is not misleading: electrons moving in a vacuum in the opposite direction.
- cathode grounded circuit is connected in circuit to close the path for the output current. Electrons warming the active layer, here not branch off for obvious reasons.
- At the output is a bandpass filter inductance and capacitance which serves to filter out unwanted harmonics.
Fullwave operates in a similar manner instead of the diode lamp is used biplate valve tube. As a result, it is possible to improve efficiency. The output current is removed at the midpoint, which is always flowing in the direction indicated in the figure. The circuit is an analog of the diode bridge.
The first variant of the scheme used to reduce the cost of the design and downsizing. At the same time consumes more battery supply. The reason - rectified only a single half-cycle fluctuations of the input voltage. At the filter output is usually stored residual frequency pulsations matched with this network. Even in Stalin's time schemes are sometimes equipped with selenium or kuproksnymi semiconductor diodes. Recall, based on copper oxide in 1874 by Karl Ferdinand Braun opened rectifying properties nonmetallic elements (see. A semiconductor diode).
Full-wave circuit previously considered common for the supply of low-power radios. ripple frequency is out twice, but the amplitude is less than a half-wave pattern at equivalent filters harmonics. Big disadvantage: the number of working windings must be increased to achieve a similar cascade gain. Consequently, a high-voltage circuit.
Rectifier tubes with voltage doubler
The scheme with voltage multiplication (twofold) going on two valve tube (lamp diodes). This will be a price to pay for the increased voltage. As is easily seen from the figure, the valve tube includes forward, due to which first passes a current in a positive direction, and the second - in the negative. The obvious advantage scheme: transformer becomes smaller, and the secondary winding is under less strain. Heating circuit separately for both lamps, no other way: kenotron would short-circuit the cathode to the anode.
The dashed line here shows a diagram of stress relieving without doubling acceptable to use with the loss of system efficiency. Insufficiency filtration in modern electronics easily improved by applying circuit common to import machinery, one shown in Fig. This is a typical solution for washing machines, require the presence in the house of TN-S earthing system. Protective and zero wires should not touch at any point. This provides a noise filtering phase and neutral at the same time, which ultimately extend the life of the electronics in the house.
pulsation frequency doubler circuit doubled, both half-waves are used. Valve tube may be replaced by semiconductor diodes with no loss of performance scheme. It is recommended to provide a separate power supply cathodes kenotron, an additional feature: if directly grounding one end of the secondary winding neutral voltage output connected to ground anymore. It is better to perform a ground through a capacitor capacity 500 - 1000 uF.
Simple diodes may be replaced by biplate kenotrons the cathodes are electrically isolated from the single filament. This is done when there is a general (on the device) power supply transformer. Then the filament is fed from the public network (heating power) and separated from the rest of the iron-hydrogen resistor (current limiter vacuum). Otherwise scheme differs little from that presented above.
Semiconductor rectifiers circuits
Semiconductor rectifier quadrupled voltage will please fans of home experiments. With the help of this gizmo will be able to strongly magnetize metal rod as Arago in 1820 (on the what we know from his own notes published in Volume XV of the journal Annales de chimie et de physique). In the four years before the invention of William Sturgeon! Arago wire saw action with electric current on the metal filings, but not given hue observation practicality or commercialization.
The scheme is simple, but shows a lack of - need somewhere to score four high-voltage capacitor. The voltage specified on each image, and it is permissible to be guided in the selection. Capacitors must not be electrolytic, a sign at the contacts change. Plus and minus are given only to illustrate the formation of the output voltage.
On the positive half-cycle charging lower pair of tanks, and on the negative - the top. The capacitors in each pair are connected in parallel (see. capacitors connected in parallel) and series (see. series connection of capacitors) simultaneously. Despite it's time for some half-period. Better to take the same denomination.
Valve tube and solid state rectifiers
Above intentionally omitted all known circuits in the solid-state electronics, are often seen in the diode bridge issue. Naydutsyatam and three-phase solutions, including those owned by Larionov. It is more important to consider the criteria kenotrons choice. Subjects ancient literature are hard to find among internetskogo dam, it made sense to dwell on the old hardware components.
In record and in concert tube amps are popular today. They cost money. Buy fails to everyone, but to gather his own... The artists say that the sound is rich voluminous. The author comes to even hear that, they say, from the speaker vibration in tubes electrons fly in a special way. That's why the sound is so distinctive.
- An important parameter is considered to be the maximum reverse voltage. As with the solid-state technique, can hurt: avalanche breakdown is formed due to electron emission from the anode. Accompanied by a considerable temperature burn lamp.
- Internal resistance is called the inverse of conductivity lamp open. It is determined from the current-voltage characteristics of the device (see. Fig.). As for a conventional diode is required the potential difference divided by the current. The values are taken over a selected operating point, or to the maximum input voltage.
- The maximum pulse current and the voltage can exceed the average rectified value. You need to make sure that the lamp does not burn in the existing conditions.
