SU1647759A1 - Method of regulation of power line energy transfer - Google Patents

Abstract

The invention relates to electrical engineering and can be used to automatically regulate power flows through interconnection lines. The purpose of the invention is to increase reliability. To do this, the adjustment of the flow regulator setpoint is made according to the found value of the marginal static power transmission power stability. The latter is determined by the parameters of the step change in power in the network elements adjacent to the starting node of the transmission. The location of the disturbance in the interconnected power system is based on the analysis of stepwise power changes in the network elements adjacent to the transmission unit. If the total value of these powers in these elements is equal to the power of the transmission, then the location of the perturbation position is adjacent to the power system. 1 il.

Description

The invention relates to electrical engineering and can be used to automatically regulate power flows through interconnection lines.

The purpose of the invention is to increase reliability.

The drawing shows a schematic diagram of a device implementing the proposed method.

The device contains a bus 1 starting node intersystem transmission, bus 2 neighboring power system, intersystem transmission 3, generating sources 4 of the considered power system, connected to tires 1 using internal power transmission, the equivalent generator 5 of the power plant, adjacent to the starting node transmission, power sensor 6, sensor T step change of power, the device 8 fixing the initial load of the transmission, the adder 9, the device 10 comparison, the setpoint 11 of the setpoint power flow regulator Bars, setpoint correction device 12, mismatch device 13, power flow controller 14, power control distribution unit 15 for processing power of regulating power plants, device 16 determining the amount of power plant synchronizing power adjacent to the transmission unit, power transmission timing determiner 17, block 18 determine the maximum value of static stability of power

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power transmission 3, block 19 voltage clamping on generator tires 5, block 20 voltage clamping on tires 1 of the transmission unit.

The device works as follows.

The occurrence of unbalance of power in one of the power systems connected by power transmission 3 causes a stepwise change in the power of the generating sources (power plants) that are electrically connected with the point of application of the disturbance. The indicated stepwise power variations are proportional to the unbalance magnitude and synchronizing powers of the generating sources with respect to the place of application of the disturbance. If unbalance occurs in the neighboring power system 2, then the magnitude of the step change in the power of the transmission 3, adjacent to node 1, is equal, according to Kirchhoff’s law, to the sum of the step changes in the power of the remaining connections of node 1. These connections are a power station with an equivalent generator 5 and a number of internal transmissions connecting the generating sources 4 to the busses of the node 1. The indicated power changes are recorded by the sensors 7 and summed up in the adder 9.

The sum obtained in the device 10 is compared with the magnitude of the step change in the power of the transmission 3. When they are equal, the device 10 generates a blocking signal, which is fed to the controller 14 of the power flow and excludes the integral component of the control action of the regulator. This provides a selective action of the regulator 14. In the case of unbalance in the considered power system, a step change in the power of the transmission is less than the total step change in the power of the other connections of node 1, and an output signal appears at the output of the device 10, which is activated by the integrating element of the controller 4,

Thus, in the unbalance of this power system, the regulator 14 of the overflow produces a controlling effect on the change in power of the regulating power plants proportional to the sum of the deviation of the overflow from the set value (setpoint) and its integral component. The control action of the regulator is distributed by block 15 between the regulating power plants of the power system.

Correction of the flow control setpoint, the need for which arises when

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the change in the maximum by static stability of power transmission is performed as follows.

The device 16 determines the amount of synchronizing power Rcc of the equivalent generator 5 with respect to the buses of node 1 in accordance with the expression: p UiUs where Ui, Us are voltage modules, respectively, on the buses of node 1 (fixed by block 20) and tires of generator 5 (fixed by block 19 );

xi5 - reactance;

dis is the initial value of the mutual angle.

The parameter xi5 is assumed to be set, and a line model from generator 5 buses to node 1 busses can be used to determine the mutual angle. To calculate 615, the model requires information on the loading of the specified line. This information goes to device 16 from power sensor 6,

The magnitude of the synchronizing power of the Re-transmission is determined by the device 17 by the expression

r Mr Rap Rap - Kse.

Where A is Rap, A is Res-step changes in power transmission and power plants recorded by respective sensors 7.

To determine the RSAP, the input of the device 17, in addition to the recorded values of A Rap and A Res, is supplied with the amount of synchronizing power RSe obtained in device 16.

The maximum static power of transmission is determined by the block 18 by the expression

R - VPf p + Pin where R EP the magnitude of the power flow for transmission, fixed by the device 8.

A signal from the output of the device 18, proportional to the value of RT, is fed to the input of the device 12 for the correction of the setpoint of the flow regulator, which determines the amount of correction by the expression

URep + (RSE

A REP s 2

 2grs

Ph

ep

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where PH is the regulatory sustainability margin of power transmission.

A signal from the output of the device 12, proportional to the amount of correction of the setpoint A Py, is fed to the input of the error device 13, where it is summed with the signal of the value of the setpoint of the regulator coming from the setpoint generator 11,

The output signal of the error device 13 is determined by the difference between the current value of the power flow detected by the power transmission sensor 6 and the adjusted setpoint value.

The error signal (deviation) is fed to the input of the regulator 14 of the power flow, which produces a controlling effect on the change in power of the regulatory power plants of the power system.

FORUMAWLAH AND ISLANDS

The method of controlling the power flow over the power transmission linking the two power systems, each of which contains a power station adjacent to the dispatching power transmission center, to which the internal power lines of this power system are connected, according to which the power flow over power is measured, compared to the setpoint and proportional to the sum received deviation of the power flow and its integral component, change the power of the regulating power plants of this power system; awn in interconnections and, if power imbalance arose in the adjacent grid, is excluded from the

the obtained sum is an integral component, characterized in that, in order to increase reliability, the power of the power plant adjacent to the starting node of the power transmission and the power of the internal power lines connected to the sending node of the power transmission are measured, when the power balance is unbalanced, a step change in the power of the transmission (D Rap), as well as power plants adjacent to the starting node of the transmission (L P3s) and the total step change in the power of the internal transmission connected to (the power transmission unit ZAPi, and change the setpoint of the power flow by the value LRu, which is determined from the expression

V Ypin Pcac-) ES

where Rap power flow over power;

RSe-synchronizing power of the power plant in relation to the starting node;

PH - regulatory margin of power transmission, while the fact of unbalance in the adjacent power system is established when equality is

AREP ARES + ZAp i.

Claims (1)

Claim A method of regulating a power flow through a power transmission linking two power systems, each of which contains a power station adjacent to the starting power transmission unit, to which internal power transmissions of a given power system are connected, according to which the power flow through a power transmission is measured, compare it with the set point and in proportion to the sum of the received flow deviation and its integral component, they change the capacity of the regulatory power plants of a given power system, while revealing the power imbalance in interconnections and, if power imbalance originated in the adjacent grid, the received sum is excluded from integration time, characterized in that. in order to increase reliability, measure the power of the power plant adjacent to the 5th power supply node, and the power of domestic power transmissions connected to the starting power transmission node, with power imbalances, determine the stepwise change in the power transmission power (Δ P _E p), as well as the power plant adjacent to the starting power transmission unit (Δ P ₃ s) and the total stepwise change in the power of internal power transmissions connected to _{(from the} 15 right power transmission unit ΣΔΡι, and change the power flow setting to the value of ARu, which is determined from the expression ^{20 ΔP} U Ur2 _{p +} (p _ses · - ^p n - Rap. where Rap ^{is the} flow of power through power transmission; RCS ~ synchronizing power 25 of the power plant in relation to the starting node; Rn ~ the normative margin of stability of power transmission, while the fact of unbalance in the adjacent power system is set to 30 when the equality Δ Rap - Δ Res + ΣΔΡι.