SU478427A1 - Bridge generator of sawtooth current pulses - Google Patents

Description

(54) BRIDGE POWER GENERATOR PULSE CURRENT CURRENTS

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The invention relates to a pulse technique.

A bridge generator of sawtooth current pulses is known, which contains a square pulse shaper, adjustable keys included in the bridge circuits, one of the diagonals of which includes an inductive load, and the other a current source, and energy recovery diodes.

However, the known generator is characterized by a lack of precision in controlling the amplitude of the pulses.

The aim of the invention is to improve the accuracy of controlling the amplitude of the pulses.

For this purpose, a diode and a transistor, to the base of which a control voltage is applied, are connected in series with the current source to the second bridge diagonal.

The drawing shows a diagram of the generator.

The saw blade current generator contains a driver of direct coal pulses 1, controlled switches 2-5, diodes 6-9 intended for recovery, inductive load 10, additional diode 11 and transistor 12

(current source and control voltage source not shown).

The control inputs of the square pulse driver are indicated by the numbers 13, 14.

The generator works as follows.

There is no current through the transistor if the control keys 2-5 are closed. When opening any pair of keys 2-5, the transistor 12 begins to operate in the emitter follower mode, the coefficient () of the transmission factor with a voltage close to unity. The voltage on the inductive load 10, which in this case is connected to the transistor 12, is equal to the output voltage of the source (not shown) of the control potential (the latter can be used, for example, a code-voltage converter).

If the time constant of the load circuit iO is much longer than the closure time of the keys 2-5, then the current in load 10 increases almost linearly, and it is proportional to the voltage on load 10. Thus, the control of the potential of the cell changes the pulse voltage of the sawtooth current in tiBnu load 10, i.e. controls the amplitude of these pulses in proportion to the control potential. Upon receipt of a triggering pulse, depending on the received code of the sign, the bridge controlling the keys, the rectangular voltage pulse is applied to certain keys that specify the polarity (or direction) of the generated current. Suppose, for definiteness, that the control pulse nocTjrnaeT to the control inputs of the control keys is 3.4. In this case, during the formation of the sawtooth current, the controlled keys 3, 4 are opened. After the end of the rectangular control pulse, the keys 3, 4 are closed, and the magnetic field energy stored in the inductive load H is recovered from it in the following direction: inductive load 1O - diode 9 - positive pole of the power source - negative pole - diode 6 inductive load 10. The generator works in a similar way when a control pulse arrives at other keys. In this case, during the forward stroke, the controlled keys 2 are opened; 5. The energy stored in inductive load 10 is recovered into the power source by diodes 7, 8. Diode 11 disconnects grass 12 from the writing source during energy recovery from load 1 O Subject matter Bridge generator of sawtooth current pulses containing the driver controlled impulse keys, the control inputs of which are supplied with signals of the rectangular impulse generator, included in each arm of the bridge, in one of the diagonals of which inductive load is included, and in the second A diagonal current source and diodes for energy recovery, which are different from the fact that, in order to improve the control of the amplitude of the pulses, a diode and a transistor with a control voltage applied to the second diagonal of the bridge in series with the current source.

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