RU2041561C1 - Process of control over electron commutator of a c output circuit and device for its realization - Google Patents

Abstract

FIELD: electrical engineering. SUBSTANCE: invention provides convenient conditions of work for person switching lighting system on and off with the aid of sensors. In compliance with invention one and same sensor is acted on with actions following one after another when switching on and off with the help of phase-shifting unit to perform ignition of filament of switched-on lamp with receipt of sufficient information on operation of sensor and maintenance of illumination when person leaves room. EFFECT: provision of operational conveniences for operating personnel. 8 cl, 3 dwg

Description

 The invention relates to a pulse technique, namely to electronic switching of an alternating current circuit, is a method and device for controlling a switch of an output alternating current circuit using sensory means and can be applied to create comfortable lighting conditions for rooms.

 A known method of phase control of the electronic (thyristor) switch of the output AC circuit, which is characterized in that a half-wave of alternating voltage is applied to the control electrode of the thyristor of the switch, the phase of which can vary with respect to the phase of the supply anode voltage. In this case, the moment of unlocking the thyristor changes and, accordingly, the duration of the load connection and the supply voltage changes.

 The disadvantage of phase control is the dependence of the power given to the load on the ambient temperature. The indicated temperature instability is caused, on the one hand, by the temperature-dependent parameters of the thyristor unlocking circuit, and on the other hand, by a slow increase in the control voltage (current) characteristic of the phase control method. In addition, a slow increase in control voltage (current) leads to overheating of the thyristor and a decrease in switching reliability.

 Greater accuracy and stability of inclusion provides a method of pulse-phase control. The known method is characterized in that pulses with a steep edge are applied to the control electrode of the thyristor of the switch, changing the position of which relative to the phase of the anode voltage, they obtain the necessary unlocking angle and, accordingly, change the current through the load.

 If the load is a lighting device (incandescent lamps), then when using the known method, a sufficient lamp life is not provided. As you know, the resistance of the cold filament of incandescent lamps is 8-10 times less than that of incandescent ones. Therefore, the use of a method that does not limit the starting current of the lamp leads to an accelerated output of the filament.

 The prototype method and device are free from the aforementioned drawback and, by technical nature, are closest to the present invention.

 The prototype method is characterized in that the control pulses are formed with a steep edge and their phase angle is changed relative to the phase of the switched voltage, while during switching on the phase angle is gradually reduced to zero and when turned off, it is gradually increased to π.

 The prototype device contains a threshold circuit at the input of the thyristor switch, a phase-shifting unit with a shunt transistor, a timing differential RC circuit and a sensor means.

 The prototype solution allows the starting current limiter of the lamp and, in addition, after turning off the lamp, maintains its cross section for 5-10 s.

 However, this solution does not create enough comfortable conditions for a person turning on and off the lighting using sensory means.

 To create comfortable conditions, it is necessary to provide, upon switching on, which begin by affecting the sensor, accelerated flare of the thread, and upon switching off, which also begin by affecting the sensor, a quick but insignificant brightness drop for a time sufficient for a person to leave the room. Illumination of the thread when turned on and a slight brightness drop when turned off are sufficient visual information about the operation of the sensor.

The subject of the invention is a method for controlling an electronic switch of an output AC circuit, which consists in generating control pulses with a steep edge and changing their phase angle φ relative to the phase of the switched voltage, while during switching on, the angle φ is gradually reduced to zero, and when turned off, it is smoothly increase to π, after which the supply of control pulses is stopped, and characterized in that in the process of switching on, which is started by acting on the sensor, before smooth deceleration by decreasing the angle φ to zero set acceleration phase angle ^{140 °} <φ ₁ ^<160, and a shutdown process, which is also beginning to impact on the sensor, before flowing over hundreds of half-cycles of switching voltage increasing angle φ to π increase the phase angle for the first complete half cycle 30 ^of <φ ₂ <45 ^about and save the angle φ ₂ subsequent hundreds of half-cycles of the switched voltage.

 The specified set of operations allows, along with extending the service life of lighting devices (incandescent lamps), to create comfortable lighting conditions for a person, since when you click on the on sensor, the lamp filament is illuminated, and when you press the off sensor, the brightness is reset to obtain sufficient information about the sensor’s response and sufficient lighting for the time a person leaves the room.

 The present method has the development, consisting, according to the invention, in that the processes of switching on and off begin by successive actions on the same sensor. This creates additional convenience for the user.

Another development of the proposed method for controlling the switch is that a smooth decrease in the phase angle to zero during the conclusion process is accelerated upon reaching an angle of 60 ^about <φ ₃ <75 ^about . This allows, after a smooth heating of the filament of the lamp and a sufficient increase in resistance, to quickly exit to the full glow clip.

 The subject of this invention is also a device for controlling an electronic switch of an output AC circuit, comprising a threshold device, the first output of which is connected to a control input of an electronic switch, a controlled phase-shifting unit, the output of which is connected to an input of a threshold device, a timing circuit, the output of which is connected to the first input of a controlled phase-shifting node, a sensor means and characterized in that it introduced two triggers and a state sensor of an electronic switch, the threshold device and the controlled phase-shifting unit are equipped with a second output and a second input, respectively, and the timing circuit is integrating, while the sensor means is connected to the counting input of the first trigger, the direct and inverse outputs of which are connected to the S and R inputs of the second trigger, respectively, the second input of the controlled the phase-shifting unit and the input of the timing chain are connected to the direct output of the first trigger, in which the inverse output is connected to the D-input, the second output of the threshold device is connected to etnym input of the second flip-flop, a direct output of which is connected to the output of timing circuit, and the D-input to the output of the sensor electronic switch states.

 This block diagram of the electronic switch control device allows, acting on the same sensor, to illuminate the lamp thread when turned on and reset the brightness when turned off to obtain sufficient information about the operation of the sensor and sufficient lighting for the time a person leaves the room.

 According to the invention, the device has a development concerning the simplest and most effective, and therefore preferred embodiment of a controlled phase-shifting unit, characterized in that said unit is made in the form of a serial RC circuit, the capacitor of which is the output of the unit, three transistors and an additional capacitor, while the collector has a gap the emitter of the first transistor is connected to the circuit shunting the capacitor of the RC circuit, the collector of the first transistor is connected to its base through the collector-emitter gap in the second transistor, the base output of which is the first input of the node, and through a chain of series-connected additional capacitor and the collector-emitter gap of the third transistor, the base output of which is the second input of the node.

 In this case, an additional capacitor can be included in the collector or emitter circuit of the third transistor.

 An additional difference of the proposed control device is that the state sensor of the electronic comparator is made in the form of a diode connected in series with the first and second resistors, and a capacitor connected in parallel with the second resistor and which is the output of the state sensor.

 In FIG. 1 shows a block diagram of a device that implements the method; in FIG. 2 is a schematic diagram of a controlled phase-shifting unit (assembly); in FIG. 3 is a circuit diagram of a device for implementing the method.

 The block diagram (Fig. 1) contains a switch 1, for example, using a thyristor in the diagonal of a diode bridge (see Fig. 3), a threshold device 2, the first output of which is connected to the control input of the switch 1, a controlled phase-shifting unit 3, the output of which is connected to the input of device 2, for example, an RC circuit 4, the output of which is connected to the first input of block 3, sensor means 5, sensor 6 of the state of switch 1, two triggers 7 and 8.

 The sensor device 5 is connected to the counting input of the trigger 7, the direct and inverse output of which is connected to the S and R inputs of the trigger 8, the counting input of which is connected to the second output of the device 2. The direct output of the trigger 7 is connected to the second input of the block 3 and the input of the timing circuit 4 , the output of which is connected to the direct output of the trigger 8. The output of the sensor 6 is connected to the D-input of the trigger 8.

 The threshold device 2 can be performed, for example, on a two-transistor analog of a thyristor.

 Block (assembly) 3 contains (see Fig. 2) an RC circuit 9, 10, transistors 11, 12, 13 and a capacitor 14 included, for example, in the collector circuit of transistor 13. Another possible inclusion of a capacitor 14, i.e. its inclusion in the emitter circuit of transistor 13 is shown in FIG. 3.

 The sensor 6 can be made in the form (see Fig. 3) of the capacitor 15, the diode 16 and the resistive divider 17, 18.

 The principle of operation of the flowchart of FIG. 1, according to the invention, is as follows.

 Let in the initial state at the direct output of the trigger 7 and, accordingly, at the S-input of the trigger 8 and its direct output, a low logic level is set. The capacitor of the timing circuit 4 is not charging, the transistors of block 3 (see Fig. 2) are closed, and the capacitor 10 of block 3 is not shunted. The voltage phase at the input of the threshold device 2 practically coincides with the phase of the supply voltage, and when the device 2 is triggered, the thyristor of switch 1 is unlocked almost without delay (the angle is close to zero). The maximum power is given to the load 19 (the lamp burns brightly).

When you click on the sensor (button) 5, trigger 7 is transferred to a single state. A high logic level is supplied to the S-input of trigger 8, setting it also to a single state, and opens the transistor 13, which, in turn, opens the transistor 11 of block 3 (see Fig. 2), but for the time of charging the capacitor 14 of block 3 , which is an order of magnitude less than the charge time of the main capacitor 10 of block 3. Therefore, the shunt action of the transistor 11 appears only during an insignificant part of each half-cycle of the supply voltage. Thereby, a “delay” _{of the} charge of the capacitor 10 is achieved and, accordingly, a later unlocking of the thyristor of the switch 1. That is, when the lamp is turned off, which starts by acting on the sensor 5, the lamp 19 slightly, but abruptly fades, informing that after about 10 -15 s the light will turn off completely.

 Further, the shutdown process develops as follows.

As the capacitor charges the timing circuit 4, for example after 7-10 s, the composite transistor 12, 11 of block 3 leaves the cutoff region. The transistor 11 begins to increasingly shunt the capacitor 10 of block 3 for the duration of each half-cycle of the supply voltage. The thyristor of switch 1 begins to unlock later (the angle φ gradually increases from φ ₂ to π) and by the time the transistor 11 is saturated, it does not unlock at all, since the voltage at the input of device 2 does not reach the threshold level. Lamp 19 is off.

Thus, immediately after exposure to the sensor, the lamp 19 goes out, is in this state (φ φ ₂ ) for example 7-10 s, and then goes out smoothly (the angle φ gradually increases from φ ₂ kπ) for, for example 3-5 s.

The start-up process is started by repeated pressing on the sensor 5. As a result, the trigger 7 switches to the zero state and the capacitor of the timing circuit 4 starts to discharge slowly through the relatively high-impedance input resistance of block 3. At the same time, due to the presence of the trigger 8, the system quickly enters the thread illumination mode (accelerated installation angle 140 ^about <φ ₁ <160 ^about ), as in full heat after slow heating of the filament, i.e., after a relatively long step of reducing the angle φ from φ ₁ to 60 ^about <φ ₃ <75 ^about . It is carried out as follows. When the trigger 7 is switched to the zero state, a logic zero is supplied to the input of the trigger 8, and a pulse is taken from the inverse output of the trigger 7 to the R-input. The specified pulse transfers the trigger 8 to zero and the capacitor of the timing circuit 4 starts to be rapidly discharged along the circuit connecting it with the direct output of trigger 8. The indicated accelerated discharge of the capacitor continues until the transistors 12, 11 of block 3 begin to close (transistor 13 is initially closed due to the low level at the direct output of trigger 7).

 As soon as the transistors 12, 11 are locked up, the voltage at the output of block 3 rises to a threshold level, device 2 is activated, and its first output pulse, opening the thyristor, will begin to illuminate the filament.

 The same pulse from the second output of block 2 is fed to the counting input of trigger 8 and, since S 0, R 0 (work in counting mode is enabled), it transfers to the direct output the state of the D-input, at which a high level taken from sensor 6 states of the switch 1.

 The appearance of a high level at the direct output of trigger 8 stops the accelerated discharge of the capacitor of the timing circuit 4. The discharge time constant of the indicated capacitor and, accordingly, the closing time of transistors 11, 12 increases significantly.

As the relative slow closing of the transistors 11, 12 of block 3, the phase angle φ decreases from φ ₁ to zero. The duration of the open state of the thyristor switch 1, respectively, increases. This process occurs smoothly for, for example, a few seconds. Then, after the load (lamp) 19 enters the heated thread mode (angle φ φ ₃ ), the potential at the output of the sensor 6 (see capacitor 15 in Fig. 3) decreases to a low level, which is transferred to the direct output of trigger 8, and the discharge of the circuit capacitor 4 up to the level of logical zero on the plates again accelerated. Accordingly, the lamp 19 goes into full glow mode accelerated.

 A better embodiment of the invention is shown in FIG. 3.

 According to this scheme, a sample device was made. The tests performed showed its reliable operation with the creation of comfortable lighting conditions for the room.

Claims (6)

1. The method of controlling the electronic switch of the output AC circuit, which consists in the formation of control pulses with a steep front and changing their phase angle relative to the phase of the switched voltage, while during the switching on phase phase angle is gradually reduced to zero, and when turned off, gradually increased to π, then the supply of the control pulses, characterized in that during start that start exposure on the sensor, acceleration set angle φ _1> 140 ^°, and during turn-off, which is inayut also influence the sensor, before flowing over hundreds of half-cycles of switching voltage phase angle increases to π its increase during the first half period until the full angle 30 ^° <φ ₂ <45 ^° and retain this angle hundreds subsequent half-cycles of switching voltage. 2. The method according to claim 1, characterized in that in the process of switching on, changes in the angle are further accelerated when it decreases to a value of 60 ^° <φ ₃ <75 ^° .
3. The control device of the electronic switch of the output AC circuit, containing a threshold device, the first output of which is connected to the control input of the electronic switch, a controlled phase-shifting unit, the output of which is connected to the first input of the controlled phase-shifting node, a sensor, characterized in that two triggers are introduced into it and the state sensor of the electronic switch, the threshold device and the controlled phase-shifting unit are provided with a second output and a second input, respectively, and a timing circuit made integrating, while the sensor is connected to the counting input of the first trigger, the direct and inverse outputs of which are connected to the S- and R-inputs of the second trigger, respectively, the second input of the controlled phase-shifting node and the input of the timing circuit are connected to the direct output of the first trigger, which has an inverse output connected to the D-input, the second output of the threshold device is connected to the counting input of the second trigger, the direct output of which is connected to the output of the timing circuit, and the D-input to the output of the electronic commu tator.  4. The device according to claim 3, characterized in that the controlled phase-shifting unit is made in the form of a serial RC circuit, the capacitor of which is the output of the unit, three transistors and an additional capacitor, while the collector-emitter junction of the first transistor is included in the circuit shunting the RC- capacitor circuit, the collector of the first transistor is connected to its base through the collector-emitter junction of the second transistor, the base terminal of which is the first input of the node, and through the circuit from an additional capacitor connected in series and the collector-emitter junction of the third transistor, the base terminal of which is the second input of the node.  5. The device according to claim 3, characterized in that the state sensor of the electronic switch is made in the form of a diode connected in series with the first and second resistors, and a capacitor connected in parallel with the second resistor and which is the output of the state sensor.  6. The device according to claim 4, characterized in that the additional capacitor is included in the collector circuit of the third transistor.  7. The device according to claim 4, characterized in that the additional capacitor is included in the emitter circuit of the third transistor.

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