SU1309295A1 - Device for switching load when the given instantaneous value of sine voltage occurs - Google Patents

Abstract

The invention relates to the field of electrical engineering. It is intended to switch on the load, e.g., incandescent lamps, for a given instantaneous sinusoidal voltage. The purpose of the invention is to improve noise immunity and stability. The device contains a triac 1 through which the load 3 is connected to the AC mains 2, a single-half-voltage source 4, a direct current source 5, a single junction transistor 6, auxiliary thyristor 7, an RC circuit 8 in the emitter circuit of a single junction transistor, contact 9 switch. To achieve this goal, the top base of the single junction transistor is connected to a single-phase voltage source, the control electrode of the triac is connected via a switch contact, and the auxiliary thyristor is connected to a DC source. New interconnections ensure that the load is always switched on at a certain polarity of the half-period of the supply voltage, which makes it possible to increase the measurement accuracy of the starting currents when the load is switched on, and also makes it possible to turn on the load at a certain point in time with respect to the supply voltage sinusoid. The voltage is applied to a sinusoidal load, which eliminates the interference of the measuring instruments. 2 Il. (L oo o so yu CD cl

Description

one

The invention relates to electrical engineering and is intended to include a load, such as incandescent lamps, for a predetermined instantaneous value of a sinusoidal voltage.

The purpose of the invention is to improve noise immunity and stability.

FIG. 1 shows a block diagram of the device; in fig. 2 is a schematic diagram of the device, an embodiment.

The device (Fig. 1) contains a triac 1 through which a load 3, a single-wave voltage source 4, a direct current source 5, a single junction transistor 6, whose upper base is connected to a one-wave voltage source 4 and the bottom one is to the control electrode B1; Those of the 1st thyristor 7, RC-circuit 8 in value vv.iiTTep. i OD (OP1. pex (other trays: and; mountain 6, ||| rav.) 1iii electrode of the simpstor through contact 9 1 k; 1) 1 and auxiliary thyristor 7. connected to the source 5 of direct current.

Schematic diagram of the device {4) ig. 2) a triac 10 is supplied; through which the load 3 is connected to the cross section and the alternating current (terminals 1 1 and 12), a source of unstabilized direct current formed by the transformer 14, a rectifying bridge is, a separation diode 16, filter capacitor 17 is limited. a resistor 18, a one-step transistor 19, the upper base of which is connected to the source of half-wave nanowire) through resistors 20 and 21, and the lower to control electrodes of auxiliary thyristor 22 and blocking 1I) source) 23 through resistors 24 25, XC circuit, state of resistor 26 and capacitor 27, resistor 28, switch disconnector 29, source of stabilized voltage, node. Rented to 1MMs 30 and 31, a stable current generator, formed by Grandestor 32, the base of which is connected to the source of the stabilizer through potentiometer 33 and resistor 34. 1izirovan} th i a n p yu (terminals 30 and 31).

The device uses a combined circuit in 1md, 1d, 1 gulu.en two-period and one-half-wave paired.

The device works as follows.

Switch 29 is in the open state. AC voltage is applied to terminals 11 and 2 and goes to the primary winding of the transformer 14, and from the output of the transformer to the diode bridge 15. The transformer eliminates the reduction in the voltage grid and, by synchronizing the control circuits with voltage the power circuit of the triac 10. From the output bridge 15, through an isolating bridge 16, a steady state is fed to the filter capacitor 17 and through

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The limiting resistor 18 enters the control circuit of the simistor 10 (the cathode is the control electrode). But since the contact of the switch 29 in the control circuit

Since the triac 10 is open, the triac 10 is in the closed state, and the AC mains is not supplied to the load 13.

The upper base of the single-junction transistor 19 is powered by a single-period voltage, synchronizing its operation. To obtain a half-wave voltage, a part of the rectifying bridge 15 is used (half-bridge circuit B1) 1 ml). When you turn on the source of Stabi. The voltage across the base of transistor 32 begins to flow, determined by the dividers of the voltage formed by potentiometer 33 and the resistor%: 34. Amplified by transistor 32, the current through the throttle 26 begins to charge capacitor 27.

20 As soon as the terminal on the capacitor 27 reaches the threshold opt; pa1 and the single junction transistor 19, the latter will open. Through the opening of the transistor 19, the capacitor 27 is discharged to) the resistor 28. The l-lMg pulse voltage, which is 1 on the reg ister 28 when the capacitor 27 is discharged through the resistors 24 and 25, is fed to the lock electrodes 01H) TupiiC i Cjpa 23 and auxiliary m; 1; 1Histor 22. lijJOKi-sporacous thyristor H1nnunt source of one2Q of a full-period C11ichrony of its own voltage, blocking 1 of the subsequent one and m. i9 during the remaining period of synchronization; about tension.

35 The auxiliary thyristor 22 in the moment of arrival of the control pulse from the | | azr - yes capacitor 27 cannot be switched. since the anode price is open by the switch off. 1Я 29. Angle VK; 1Clock a blocking thyristor 23 and auxiliary thyristor 22 о: determined; TCJKOM charge through the transistor 32 and nosgo and; time of the RC circuit 26 m 27 and op) food. the time of the switching of the two switches, and consequently, of the sim- nstor 10, but from the moment to the instantaneous value of the sine wave | ;, of the normal supply voltage and can be permanently set by potentiometer 33 in the range of 10-170 e. hail.

After installing the required (switch: switch on the spystors 10 locks Koii iaKT you 5Q key 29, but BCHOMOI button :: | thyristor 22 can be turned on only with n:) and /: control pulse, the phase of which depends on RC-Koirrypa 27 and 28 With the first 1 CRPmp. Pulse yii | iai ..ieiniH from one transistor 19 turns on

55 all the necessary conditions: 22. - e | 1 is the common circuit of the auxiliary thyristor 22 and the cathode is the control e, the 1-electrode of CHM; I :: (.; I 10 scoops the leak, the current from

45

a non-stabilized DC voltage limited by a resistor 18. The simulator 10 is turned on, providing a voltage supply to the load, the instantaneous value of which is determined by the phase switched on; 1 and the auxiliary thyristor 22 relative to the sinusoidal voltage of the power supply network.

The direct current control of the triac 10 provides a sinusoidal voltage to the load after switching on the auxiliary thyristor 22 and triac 10. The synchronization of the operation of the single junction transistor by full-wave voltage is required to turn on the auxiliary thyristor 22 only at one polarity of the half-wave of the supply voltage of the network. This allows for a research study lOKO j. 11 1ote: ayi ai. via ia: py3i-: v to M () M (: iiT inc. switches, max. nciux ib- to set the gain of light and electronic and electronic recording devices, since the starting current of Hai-loop 13 always has only one polarity, which depends on the polarity of the plug of the measuring instruments to the load 13.

Invention mold

A device for turning on the load on a predetermined instantaneous sinusoid value. p. voltage containing a triac. hc cut that the load is connected to the AC network, the one-junction transistor, the lower base of which is connected to the auxiliary thyristor, the RC circuit in the emitter circuit of the single junction transistor:; that, in order to reduce the noise immunity and stability of the operation, the upper base of the unijunction thr. The resistor is connected to a mono-field source voltage, controlling elok. The genus C1 of the mystor through the contact is disconnected. 11 1 of the auxiliary thyristor is connected to the ps TO4HHKV of direct current.

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FIG. 2

Claims (1)

A device for switching on a load at a predetermined instantaneous value of a sinusoidal voltage containing a triac. through which a load is connected to the AC mains, a single-junction transistor, the lower base of which is connected to an auxiliary thyristor, an RC circuit in the emitter circuit of a single-junction transistor ;;. characterized in that. that, in order to increase the noise immunity and stability of operation, the upper base of the single junction trh. the resistor is connected to the source of the same-sex period voltage control elech; the kind of triac through the switch contact and the auxiliary thyristor is connected to a constant current source.