SU1370699A1 - Arrangement for controlling the voltage of load unit of electric networks - Google Patents

Abstract

The invention relates to electrical engineering, rt can be used to control the modes of electrical systems. The purpose of the invention is to increase reliability by reducing power fluctuations. This is achieved by the fact that the switching of taps to the increase in voltage in the load nodes is not performed simultaneously, but with a shift in time, and the shift value is equal to the time of the transient change in mantiness when the voltage deviates. The device contains a time relay, which is triggered by frequency divider 12 and sends a signal to element AND 8, to the second input of which a signal from the analyzing unit 7 arrives. Inverter 11 converts the unit signal from unit 7 to a zero signal and supplies to the input of element OR 10, to the other input of which a single signal is sent from the element AND 8. The element OR 10 operates and enables the unit 2 to operate the voltage control device under load, i.e. Transformer spikes will be switched to voltage increase after a time specified by the time delay. 2 Il. (L

Description

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about

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The invention relates to electrical engineering and can be used to control the modes of electrical systems.

The aim of the invention is to increase reliability by reducing power fluctuations.

FIG. 1 is a block diagram of a device for controlling the voltage of a load node; in fig. 2 - curves of power changes in the system during voltage regulation at the load nodes versus time.

The power of the load nodes depends on the applied voltage and increases with increasing voltage, i.e. each load node is characterized by a positive regulating effect of power on the voltage of the DR,

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where u u; - node. Then

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voltage increment

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Moreover, the component LQ; many more UP; i.e. When regulating the voltage, the change in reactive power mainly occurs.

Improving the mode of the power supply system when regulating the voltage of the load nodes is that such regulation creates less power fluctuations, since large power fluctuations in the system can create its deficit, which leads to an avalanche of voltage, impaired stability and increased energy losses.

The reduction of power fluctuations during voltage regulation can be achieved by the fact that switching of taps to increase voltage in the load nodes was not performed simultaneously but with a time shift.

Moreover, the magnitude of the shift is equal to the time of the transient process of power change when the voltage deviates.

In the case when the switching of taps for an increase in overvoltage occurs alternately with a shift in time, the magnitude of the fluctuations of the power AS is less than in the case when this switching is carried out simultaneously at each node.

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These processes are repeated periodically at a time equal to

T zir; ,

where r; - time of the transient process of changing the power of the 1st node when the voltage changes in the i-th node.

The device (Fig. O contains a load node transformer, the switching of which taps is carried out by a voltage control device 2 under load, controlled by an automatic voltage control unit 3. The unit 3 is connected to a voltage sensor 4 and through a compensation current function converter 5 to blocks 6 current compensation for waste: g,: - x connections. However, the analyzing block 7 converts the signal coming from block 3 into a discrete one: a positive signal into a single unit, a negative one - into a zero signal.

The logical element AND 8 generates a signal in the case when its inputs receive single signals from time relay 9 and the sign-analyzing unit 7. The logical element OR 10 generates a signal when its inputs either from invertoa 11 or from logical Element And 8 receives a single signal. The industrial frequency divider 12, which is the same in all system load nodes, ensures the frequency of device operation at a load node with a period T. This time sets the frequency divider 12, the division factor of which is

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The device works as follows.

When the mode of the electrical network of the automatic voltage control unit 3 is changed, the load control unit 2 of the voltage control device 2 receives a signal to switch the faults of the load node transformer. In this case, the sign of the signal at the output of block 3 determines the direction of voltage variation in the node. A positive signal corresponds to an increase in voltage, and a negative signal to a decrease.

Upon receipt of a signal to increase the voltage signamomalizing

ten

31370699

the unit generates a single signal, which is fed to the input of the logical element And, which is triggered when povuyleniya at its other input signal with a time relay. The time relay is triggered by a frequency divider 12, the input of which receives the signal of the fast frequency of the voltage sensor 4, the inverter 11 converts a single signal from the analyzing unit 7 into a zero signal and supplies the input of the OR 10 logic element to another input, and a single signal from the logical jj block and 8.

The AND 10 logic element operates and enables the block 2 of the voltage control device under load, i.e. switching of transformer spikes to voltage increase will occur after a time specified by the delay of the time relay. Time delay for individual nodes: national compensation current converter. With the aid of the voltage sensor 4, voltage feedback is carried out, i.e. This device provides the necessary law for regulating the voltage in the load node, which is the power center of the distribution network, and improves the power supply mode of the power supply system by reducing power fluctuations.

Claims (1)

Invention Formula A device for controlling the voltage of a load node of an electrical network, comprising an automatic pe20 voltage bumper acting on the switching of transformer spurs, non-linear functional load current transducer, the input of which is connected to the current compensation blocks, and the output connected to the automatic voltage regulator. gr, narrow (fig. 2), the following 25 is determined; its second input is connected with the following way: I node: II node:,; III knot: t TG, - - with. After a period of time T, the operation of the circuit is repeated. When a signal is received for lowering, the analyzing unit 7 generates a zero signal, which through the inverter converts into a single signal. This signal is fed to the input of the logic element OR 10, which triggers and enables the operation of block 2 of the voltage regulation device under load without time lag. When device 2 is triggered, a voltage is established at each load node such that the least amount of electricity is consumed outside the allowable voltage range. The required law of voltage variation in an electrical network node under load variations forms the function 35 40 45 A voltage is applied, and its output is connected to a sign-analyzing unit, characterized in that, in order to increase reliability by reducing power fluctuations, it is equipped with a frequency divider, a time relay, an inverter, logic elements AND and OR, and a time relay input through a frequency divider connected to the voltage sensor, the output is connected to the first input of the logic element And, the second input of which is connected through the sign-analyzing unit to the output of the automatic voltage regulator; th input of the OR gate, the second input of which via an inverter connected to the output znakoanaliziruyuschego unit, and the output of the OR gate is connected to a device controlling the voltage under load. Real current compensation converter. With the aid of the voltage sensor 4, voltage feedback is carried out, i.e. This device provides the necessary law for regulating the voltage in the load node, which is the center of the power supply network, and improves the power supply mode of the supply system by reducing power fluctuations. Invention Formula A device for regulating the voltage of a load node of an electrical network, comprising an automatic re voltage bumper acting on the switching of transformer spurs, non-linear functional load current transducer, the input of which is connected to the current compensation blocks, and the output connected to the automatic voltage regulator. the second input of which is connected to date0 five 0 five A voltage is applied, and its output is connected to a sign-analyzing unit, characterized in that, in order to increase reliability by reducing power fluctuations, it is equipped with a frequency divider, a time relay, an inverter, logic elements AND and OR, and a time relay input through a frequency divider connected to the voltage sensor, the output is connected to the first input of the logic element And, the second input of which is connected through the sign-analyzing unit to the output of the automatic voltage regulator; th input of the OR gate, the second input of which via an inverter connected to the output znakoanaliziruyuschego unit, and the output of the OR gate is connected to a device controlling the voltage under load. CPU fffll / fffHO but)