SU1457062A1 - Arrangement for reducing reverse flows of power - Google Patents

Abstract

The invention relates to the field of electric power engineering and electrical engineering, and can be used to reduce the return energy flow from a consumer to a network. The purpose of the invention is the elimination of reverse energy flows in chains. The current sensors 7, 10 and the voltage sensor 11 generate signals arriving at the comparators 12, 13, 14. The comparator 12 detects the instants of time when the instantaneous value of the throttle current is positive, negative, or zero. Comparator 13 determines the times for which the instantaneous value of the generator voltage 8 is positive, negative or zero, the comparator 14 is the time when the instantaneous value of load current 9 is positive, negative or zero. An operation algorithm of switch 15 is set, at which there are six intervals on the period T of the generator-load system, during which the device is connected to the network. 3 il. (L

Description

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The invention relates to electrical engineering, in particular, to devices for reducing reverse energy flow from a consumer in a network using static venil devices.

The aim of the invention is to eliminate reverse energy flows in chains with non-sinusoidal forms of currents and voltages.

. FIG. 1 shows a block diagram of the device; FIG. 2 is a diagram of the mode selector switch; FIG. 3 - time diagrams of instantaneous values of currents, voltages and powers in a generator-load system.

The device contains a valve converter 1 in the form of four fully controlled key switches 2-5 with double-sided conductivity, connected via a bridge circuit, one diagonal of which includes reactor 6 and the first current sensor 7, and the nodes of the second diagonal connected

here are the generator 8 and the load 9, the second current sensor 10, the voltage sensor 11, three comparators 12-14 and the switch 15 operating modes,

The input of the first comparator 12 is connected to the output of the first current sensor 7 included in the circuit of the throttle 6, and its output is connected to the first input of the operation mode switch 15, the second input of which is supplied to the output of the second comparator 13, the input of which is connected to the output of the voltage sensor 11 connected in parallel between the generator B and the load 9, the input of the third comparator 14 is connected to the output of the second current sensor 10 connected to the load circuit 9, and its output is connected to the third input of the switch 15 operating modes. The latter contains the decoder 16 and the chip of the amplifier shaper 17-20. -

In the switch 15 modes

the binary code generated by the comparator - - "decoder 16 has the following form

Frames 12-14 through terminals A, B. and C, is fed to the input of the decoder 16, the first output of which is connected via control amplifiers 17 and 18 to the control electrodes of the key switches 2 and 3, and the second output through the hooks forming devices 19 and 20 is connected to the control electrodes of the key switches 4 and 5.

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Fig. 3 shows diagrams (Fig. 3a) of the voltage U (t) of the generator 8 and the current) of the load 9J of the diagram (Fig. 3B) of the instantaneous power P, H (t) of the load 9; the diagram (fig, Sv) of the current iep (t) of drossel 6, the diagram (fig, Zg) of the operation of the group of key switches 2 and 3; diagram (fig, rear) of the work of the group of key switches 4 and 5; diagram (FIG. Ze) of the current if (t) of the generator 8 | diagram (5mA (fig, ЗЖ) instantaneous power Pf (t) of generator 8

The device works in the following way ;;;

Current sensors 7 and 10 and voltage sensor 11 form signals, respectively, U4, (t), ijp (t); U, 2 (t) HU (t) ciuU (t), where ": 4,, ot} o (, c are determined by the design of the sensors. These signals are sent to the comparators 12-14, respectively.

Comparator 12 determines the times when the instantaneous value

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negative or equal to zero. The signals from the comparator 12 are received at terminal A of the switch 15 operating modes. Comparator 13. Defines moments.

0 times for which the instantaneous value of the voltage U (t) of the generator 8 is positive, negative or zero. The signals from the comparator 13 are received at terminal B of the switch 15 of the operation pressures.

Comparator 14 determines the times when the instantaneous value of the current i (t) of the load 9 is positive, negative or zero. The output signals of the comparator 14 are sent to the terminal C of the operating mode switch 15.

The signals of logic 1, coming through the terminals A, B and G from comparators 12-14 to the decoder 16, correspond to zero values of analog values of I currents and voltages, signals of logic O are also zero. values of truth table of work

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where the signs indicate the preservation of the previous state of the output terminal

decoder 16, signs - assume the absence of such input codes and the corresponding emergency modes (emergency shutdown of load 9 and emergency shutdown of the generator 15 8). .

The logic 1 signals from terminals K1 and K2 of the decoder 16 through the amplifiers 17-20 unlock the fully controlled key switches 2-5, respectively, and the logic signals When the current (i) decreases, the throttle switches to zero value 5 switches 4, 5 and the load 9 consumes the full current of generator 8. This mode corresponds to integral III (t, tj).

When the polarity is changed, the voltage U (t) of generator 8 (moment t) is repeated, the processes are repeated taking into account the negative polarity of voltage U (

Claims (1)

Formula of gain 20 ik oh they are locked up A device for reducing reverse energy sweats, containing a valve converter in the form of four fully controlled key switches with two-sided conductivity, connected in a bridge circuit, in one diagonal of which the reactor-throttle is connected, and the nodes of the second diagonal are connected to the operating mode switch provided with inputs and codes, and its outputs are connected to control electrodes of key switches of a vent converter, characterized in that, in order to eliminate reverse energy in shackles chains s.nesinusoidalnymi forms currents and voltages in the two current sensors has been entered, a voltage sensor With this algorithm, the operation of the switch 15 operating modes, there are six intervals on the period T of the system generator 8 - load 9, the cross section of which is connected to the proposed device (Fig. 3). On the intverval I (t,, t), the switch 15 of operation modes closes the key switches 2 and 3, the reverse load current 9, which arises at different polarities of voltage and current on load 9, is sent to the throttle G.Ft- ng MpuuL-ejib, -, -) plagila, sensor nappnrmmo nrat opT comparator;, p „: e. s sd ne. comparator connected to the output When reaching the current i (t) turned on load 9 zero switch-° ° The cable is connected The reader has 15 modes of operation in a mONGS mode switch with the described mode. earlier algorithm, 1- °. the input of which is connected to the output of a voltage sensor connected in parallel with the generator and a load, the input of the third comparator is connected to the output of the second current sensor connected to the load circuit, and its output is connected to the third input of the switch. X, imld V j- J l 1 3 € pushes to; 1 switch switches 2 and 3 and unlocks key switches 4 and 5. This mode corresponds to interval II (t ,, tj). In interval II, the current igp (t) due to self-induction of the chokes 6 returns to load 9, while reducing the current consumption i (t) of the generator Si When the current i (t) drops to zero, the operation mode switch 15 turns off the key switches 4, 5 and the load 9 consumes the full current of generator 8. This mode corresponds to input III (t, tj). When the polarity of the voltage U (t) of the generator 8 (moment t) is changed, the processes are repeated taking into account the negative polarity of the voltage U (t). Formula of gain 15 0 A device for reducing reverse energy flows, containing a valve converter in the form of four fully controlled key switches with double-sided conductivity, connected in a bridge circuit, in one diagonal of which the throttle-reactor is connected, and the nodes of the second diagonal are connected to the generator and the load; inputs and codes, and its outputs are connected to the control electrodes of the key switches of the valve converter, characterized in that, in order to eliminate the reverse energy chains currents x s.nesinusoidalnymi shapes of currents and voltages introduced therein two current sensor, voltage sensor 0 , -, -) plagila, sensor nappnrmmo 5 comparator;, p „: e. s sd pe comparator connected to the output A: 6 with sixteen fig.g Ur (t) F fflta.3