SU980234A2 - High-voltage output inverter - Google Patents

Description

The invention relates to a conversion technique and can be used in various power supply devices for radio and electronic equipment.

According to the main author. St. No. 921001 is a high voltage output inverter used in high voltage sources for powering electronic equipment and containing serially interconnected pulse driving oscillator with synchronization input, duration modulator, key stage, step-up transformer and feedback circuit connected between the additionally introduced the winding of the step-up transformer and the synchronization input of the pulse master oscillator. The device operates in the oscillator mode at the resonant frequency of the transformer 1.

In devices of this type, the power losses in the key stage are mainly determined by the losses during the transition from one mode to another, and these losses increase with frequency.

If the resonant frequency of the step-up transformer has a value / commensurate with -, where T is a constant transistor time, the efficiency of the inverter decreases.

The purpose of the invention is to increase the efficiency of the device.

This goal is achieved by introducing into the inverter a frequency length with a division factor of 2, 3, 4, ..., N, connected between the output of the pulse generator and the input of the duration modulator.

The drawing is a diagram of the inverter.

Inverter contains serially connected impulse gene

15 rator 1 with synchronization input, divider 2 frequencies with a division factor equal to 2, 3, 4, ..., N, duration modulator 3, key stage 4 and transformer 5. Low voltage 20 to the winding of transformer 5 is connected to the input of circuit 6 zi, the output of which is connected to the synchronization input of the master pulse generator 1.

25

The inverter works as follows. . .

When the supply voltage is switched on, the master oscillator 1 begins to produce square-wave pulses, the time of which it should

less than the resonant frequency of the step-up transformer 5, These pulses are fed to the input of the divider 2 frequency. From the output of divider 2 frequencies. Pulses, the frequency of which is reduced N times (N is the frequency division factor; N 2, 3, 4 ,, ..) are fed to the input of the modulator 3 duration. Pulses from the output of the modulator 3 duration arrive at the input of the key cascade 4. Impact free oscillations occur in the secondary circuit of the step-up transformer at its resonant frequency. In the low-voltage winding of the transformer 5 a voltage is induced that is close in shape to sinusoidal. This voltage passed through The feedback circuit B is fed to the synchronization input of the master oscillator 1, which leads to an increase in its frequency to the resonant frequency of the step-up transformer 5. P; the torus operates at the resonant frequency, and the key stage operates in the saturation mode or at a frequency that is N times smaller.

The values of N are chosen to be no more than a certain value, so that the exponential voltage drop at the output of the inverter, due to the finite value of the quality factor of the transformer and the shunting effect of the load resistance, has a value within acceptable limits determined by the specific application of the inverter.

Thus, as a result of the frequency splitter, the key stage operates at a frequency that is N times less than the resonant frequency of the step-up transformer, which allows reducing power losses in transient conditions and thereby increasing the efficiency of the inverter, which operates in the synchronous excitation mode of the output transformer on a subharmonic resonant frequencies. This leads to a decrease in the power loss in the key stage — the efficiency of the device increases.

The proposed solution allows creating high-voltage sources for supplying radio-electronic equipment with high stability, efficiency and reliability in the range of temperatures.

Claims (1)

1. USSR author's certificate No. 921001, cl. H 02 M 7/48, 1980.