SU1667134A1 - Method of transmitting and receiving control commands over a three-phase power supply system - Google Patents

Abstract

The invention relates to a technique for controlling objects connected to a three-phase network, and can be used for switching networks of outdoor lighting. The purpose of the invention is to expand the scope by increasing the number of control commands transmitted. This is achieved by transmitting control commands by amplitude modulating a given half-wave AC voltage in one of the phase conductors of the network; control signals are received by fixing the increments of phase voltages in a half-wave of the corresponding polarity in two other phase conductors of the network and form a control signal to the actuating element of the respective wire of the three-phase lighting network. 2 Il.

Description

The invention relates to a technique for controlling objects connected to a three-phase network, and can be used for switching networks of outdoor lighting.

The purpose of the invention is to expand the scope by increasing the number of control commands transmitted.

FIG. 1 is a block diagram of a control device for implementing the inventive method; in fig. 2 is a vector diagram of network voltages for transmitting control signals.

The device contains a three-phase transformer 1, a switch 2, wires 3–5 of a three-phase network, a common bus 6, a three-position control switch 7, an impulse generator 8, impulse sensors 9 and 10, and actuators 11 and 12

A device for carrying out the proposed method works as follows.

To transmit a control command, the amplitude modulation of a given ac half-wave in one of the phase conductors of the network and fixing the resulting increments of phase voltages in the other two phase conductors of the network are used.

When the switch 2 is turned on, the wires Ua-Us appear on the wires 3-5 of the three-phase network relative to common bus 6 (Fig. 2) and a current of a certain amount is established in the network, depending on the load created by the actuators 11 and 12 and controlled objects. Control key 7 is in the neutral position (0).

To transmit a control command in a positive half-wave of an alternating current voltage, the control key 7 is set to position a, in which the common bus 6 is connected to the generator 8 of pulses through the 1st contact and the 3 O wire

about

four

WITH

through the 2nd contact, the Pulse Generator 8 forms in the wire 3 a wave half current of positive polarity ir, as a result of which a stream Foul is formed in the bar A of transformer 1, which is superimposed on the main flow of the three-phase transformer. In this case, in each phase winding is created

3DC Eop. which lags behind F0p at an angle n II. In phase A, Eop is opposed to the main EMF, and in phases B and C, E0p is geometrically added to the main EMF. Consequently, as a result of the action of the current pulse 1G in the phase wire 3 in the phase wires

4 and 5, voltage level increments occur, which are detected by the sensors 9 and 10 pulses, which generate control signals to the actuators 11 and 12.

After the control signal is transmitted in a positive-polarity half-wave, the key 7 is returned to the neutral position, and the pulse generator 8 is reset.

Similarly, the control command is transmitted in the negative half-wave of the AC voltage, for which the control key 7 is set to position b.

Thus, the proposed method allows to increase the number of control commands transmitted by transmitting signals by current pulses in both positive and negative half-waves.

alternating current voltage in one phase conductor and receiving commands to control latching of voltage increments in two other phase conductors.

Claims (1)

Invention Formula A method of transmitting and receiving control commands over a three-phase network wiring, based on forming a control command from a signal of a given half-wave AC voltage in one of the three-phase network wiring, transmitting a control command over one of the three-phase network wiring, receiving a control command and transforming its control signal actuator, characterized in that, in order to expand the scope of application by increasing the number of transmitted commands, the formation of a control command By amplitude modulation of the reference signal of a given half-wave AC voltage, the control command is received in each of the two other phase wires of the three-phase network by determining the phase voltage increment in it relative to the reference signal in a half-wave of the corresponding polarity and, if present, form control signal of the executive element of the corresponding wire of the three-phase network. fig1 ir (bn) Fig, 2.