SU519830A1 - Frequency doubler - Google Patents

Description

one

This invention relates to the field of electrical engineering, in particular, to alternating voltage regulators, multipliers of frequency and number of phases.

Known frequency doubler, made in a bridge circuit and contains a non-choke, the windings of which are located on two cores, and the load circuit.

The proposed device differs from the known one in that a controllable key is connected in parallel with each of said windings as well as the load circuit.

This allows you to increase the speed of the device, energy performance, eliminate overvoltage on the elements of doubled and simplify the device.

FIG. 1 shows a functional diagram of a two-core bridge frequency doubler; in fig. 2, 3, 4 given time diagrams.

The frequency doubler (Fig. 1) contains two ferromagnetic cores 1 and 2, on each of which windings 3, 4 and 5, 6 are located, respectively, connected according to a bridge circuit. In parallel with the windings 3 and 5, keys 7 and 8 are included. A load 9 is included in the bridge diagonal, and a key 10 is parallel to it.

The keys can be used any switching elements, such as relays, transistors, thyristors, etc.

In the initial state, when the windings 3, 5 are not shorted, the cores 1, 2 are not polarized and there is no constant magnetic field in them. Induction in the cores varies according to the law represented by curve 11 (Fig. 2), and since the bridge is symmetrical, the voltage on load 9 is zero. When alternately shorting the windings 3 (for example, at time 2 p) and 5 (at time (2 / g + +1), the change in induction in the cores is delayed and for a shorted state it is equal to the induction saturation (- for core 1 and -BS - for core 2). After removing the shorts from windings 3 or 5, the cores are re-magnetized according to the same law and are saturated at times uniquely related to the length of the shorted state of the windings 3 or 5. In Fig. 2, curve 12 illustrates the change in induction in the core 1, and curve 13 - in the core 2, with relative and by a similar curve 11, curve 12 is shifted by a constant component of 5oi, and curve 13 by a value of BOZ. If the intervals of the shorted state of the windings are the same, then Soi 5o2. Thus, the effect of polarization of cores 1, 2 without the use of extraneous sources of magnetization is created .

In the intervals when the cores 1, 2 are saturated or the windings 3, 5 are shorted, a voltage (curve 14) is applied to the load 9, the instantaneous value of which is equal to the network voltage (curve 15). The saturation intervals of one core and the short-circuited state of the windings of the other core must not overlap, due to which the windings are short-circuited by no more than a quarter of the period. The dotted curve 14 (Fig. 2) denotes the voltage at the load when the doubler operates in the maximum recoil mode. In order to avoid overvoltages on the frequency doubler elements, at each moment of removing the short circuits, the current is passed along the short-circuited load loop from the windings and interrupted when one of the cores 1 or 2 is saturated. Since by the time the cores are saturated, the load current does not have time to reach zero, shorting The winding of the saturable core forms a circuit for returning the excess reactive load energy to the network. The device works as follows. When the network voltage (curve 15) passes through zero (Fig. 3) and is established at the moment of polarity indicated in Fig. 1 without brackets, the control device closes the key 7, which short-circuits the winding 3 on the core 1. In the previous half-period, core 1 was saturated and when changing the network polarity, the network should be demagnetized, but since at the moment the key 7 short-circuits the winding 3, then induction Core 1 remains almost unchanged and remains saturated. The voltage drop on the windings 3, 4 is zero (curve 16), and the network voltage is applied to the load 9 (curve 14) and windings 5, 6 (curve 17) located on the core 2. At the moment, the key 7 is forcibly opened, while the voltage on the load 9 becomes equal to zero, and on the windings 3, 4 and 5, 6 equal to half of the applied network (curves 16 and 17 of Fig. 3). Core 1 begins to demagnetize (curve 18), and core 2 continues to magnetize and becomes saturated at (curve 19). In this case, the voltage on the windings 5, 6 (curve 17) becomes equal to zero, and on the load 9 (curve 14) and on the windings 3, 4 (curve 16), the network voltage. Naturally, the polarity of the voltage across the load 9 varies, although the polarity of the mains voltage remains unchanged during this half period. In the second half-period, i.e. at the moment, the control device closes key 8, which short-circuits winding 5 on core 2. The processes occurring in core 2 are similar to processes in core 1. Thus, the frequency doubling occurs. The dashed line in FIG. 3 shows diagrams illustrating the operation of the doubler in the maximum return mode when the switching angle of the keys 7 and 8 is equal to a. 6 In the case of active-inductive load 9, the processes that occur before the opening of keys 7 and 8 at moments a a. Do not change. When keys 7 and 8 are opened, depending on the polarity of the network voltage, dangerous overvoltages occur on the frequency doubler elements due to e. d. self-inductance load inductance. Here the frequency doubler works as follows. At the beginning of the half period (in Fig. 1, the polarity is shown without brackets), the switch 7 closes and begins to conduct current (curve 20 in Fig. 4) at an angle when the current (curve 21) of the load 9 becomes zero and changes its direction. At some point, the key 7 is forcibly opened, and the key 10 and the current (curve 21) synchronously closed, maintained in the external direction due to the edg. with. the self-induction inductance of the load is closed along its circuit (curve 22 in fig. 4). The load voltage 9 becomes zero, and the processes of magnetization reversal of cores 1 and 2 proceed in the same way as described under active load. When core 2 is saturated, key 10 is opened, and key 8, through which current flows, is additionally closed (curve 23). The voltage on the load changes sign to the opposite, and the current (curve 21) of the load closes on the circuit; load 9-key 8-network-winding 6-load 9 and drops to zero at the moment. The key 8 goes into a non-conducting state, the current (curve 21) changes its direction and, since the core 2 is saturated, flows through the windings 5 and 6 (curve 24 in Fig. 4). At the beginning of the next half-period (in Fig. 1, the polarity of the voltage is shown in parentheses), the control device closes key 8, which begins to be carried out from the moment and then processes repeat, but only key 8 functions are performed by key 8, and windings 3, 4 on 1-winding core 5, 6 on core 2. This period of current (curve 21) of load 9 consists of the following components: current (curve 25) through switch 8, current (curve 26) through switch 10, current (curve 27) through the key 7 when it is re-closed and the current (curve 28) through the washing 3, 4 when the core is saturated 1. Ta and the sequence of operation keys 7, 8, 10 and the cores 1 and 2 with the windings 3, 4, 5, 6 ensures independence form double frequency voltage at the load 9 on its nature. Since at any moment of time the circuit of current flow through the load is provided, overvoltage on the frequency doubler elements is fundamentally excluded. Moreover, the processes of magnetization reversal of cores 1 and 2 proceed independently of the load. The saturation angles p1 and P3 of the cores 1 and 2 are uniquely determined by the control angles ai and 02, and the output voltage is in phase with the mains. . Ph o rmly of the invention A frequency doubler, made in a bridge circuit and containing a nonlinear choke, the windings of which are located on two 5 cores, and a load circuit, which is also distinguished by the fact that, in order to increase speed, energy indicators, to eliminate overvoltages on the doubler and simplification elements, a controllable key is included in parallel with each of the windings, as well as the load circuit.

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