SU529531A1 - Transistor rectifier - Google Patents

Description

The invention relates to electrical power sources and can be used in electrical engineering or radio electronics in devices for rectifying alternating current. It is especially expedient to use the proposed extractor in low-voltage (1O V) power circuits (load current 5 A). Known transistor batteries, not containing a current transformer. However, known rectifiers have increased energy losses in the chains of the bases. The losses are due to the limiting resistors installed in the base circuits and the large base currents calculated to obtain the required minimum transistor saturation coefficient at the minimum supply voltage and maximum load currents. Limiting resistors are fundamentally necessary due to the nonlinear current-voltage characteristic of the transitions of transistors. The closest technical solution is a transistor rectifier, which uses a power transformer, a current transformer, key transistors, and diodes. The use of a current transformer in a transistor rectifier eliminates the limiting resistor, and the base current varies depending on the load current, maintaining the transistor saturation coefficient at a constant level. For these reasons, the energy losses in the base circuits are significantly reduced. The inclusion of diodes in the load circuit increases the losses in the known transistor rectifier to a level exceeding the losses in a simple diode rectifier. These diodes ensure the performance of a known rectifier. Indeed, on non-working half-periods, if there are no diodes, a parasitic collector is formed — the base winding. current transformer - load. Chaining eliminates the possibility of normal operation of the rectifier. The aim of the invention is to increase the efficiency of the rectifier.

For this, the secondary windings of the current transformer are connected in parallel with the base-to-collector transistors transitions.

This makes it possible to exclude from the load circuit the diodes that cause additional losses. The increased efficiency of the rectifier allows to improve the overall weight characteristics of power sources.

The drawing shows a circuit diagram of a rectifier,

The transistor rectifier contains a mains transformer 1, a current transformer 2. Secondary windings 2-1 transformer. current 2 is connected to the collector-base transitions of transistors 3 and 4, the load 5 is connected to the output of the rectifier, and the primary windings 2-2 of the current transformer 2 are connected in series with the load 5.

The rectifier works as follows.

At the beginning of the working half-period, (when a negative voltage is applied to the collector of a pn-transistor 3 or 4) the transistor is opened by the control current of the current transformer 2. The magnitude

The steady state value of this current is determined by the load current and the transformation ratio of the current transformer 2, which is calculated for the minimum loss in the transistor. The inclusion of the secondary windings 2-1 of the current transformer 2 between the collector and the base eliminates the possibility of the formation of a parasitic conductive circuit during a non-operating half-period in the absence of diodes in the load circuit.

The elimination of diodes makes it possible to reduce energy losses during rectification by more than 4.5 times.

formula of invention

A transistor rectifier containing a power transformer, a current transformer whose primary windings are connected in series to the load circuit and transistors, characterized in that, in order to increase the efficiency, the secondary windings

25 current transformers are connected in parallel with the base-collector transistors.

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