RU1815732C - Method for automatic limitation of power flow for electric transmission - Google Patents

Abstract

SUMMARY OF THE INVENTION: The limit of static stability of a power transmission is determined from the analytical expression using data on the magnitude of the increment of the total power transmission and the magnitude of the increment of the mutual angle between the voltages of the controlled points. Based on the found value of the stability limit, the overflow limiter setting is corrected. In addition, the correction takes into account the magnitude of the current dynamic range of regulation of consumer regulators connected to the overflow limiter and the influence of the calculated disturbance in the power system on the change in the transmission power. 1 silt

Description

Ј

The invention relates to the electric power industry and can be used to automatically limit the flow of active transmission power.

The purpose of the invention is to increase the utilization of the throughput of electronic devices.

For this purpose, the power flow is measured according to the EF, compared with the setpoint Ru and a control effect is formed on the change in the power of the RES and PR as a function of the deviation of the power flow of the retirement Ru and the fixed value of the power unbalance in the Erg system A Pr. In addition, the increment of the power drain is determined. EP A Rap from the resulting power imbalance A Rg by the expression A REP Kv A Rg, where Kv is the coefficient of influence of the calculated power unbalance on the power flow, as well as the current dynamic range of regulation of the PR by the expression A Rpr

  Kn1-K8 | A Pi, where Kn - coefficient 1 1

the reliability of the control action of the flow limiter to change the power of the 1st PR, HF | is the coefficient of influence of the change in power of the f-th PR at the power flow, A PI is the value of the adjustment range of the 1st PR, n is the number of PR. Then, the setting of Ru is determined by the expression: Ru (Ppr - A Pn) / (1 + Kn) - (A Rap - A Ppr), where Ppr is the limit of static stability of the electric power, And Pn is the amplitude of irregular flow fluctuations, Kp is the coefficient margin of ES static stability in the optimized mode with the overflow power exceeding the Ru setting. The magnitude of the mutual slip derivative a is continuously determined, it is compared with a predetermined value of az, and if the condition

00

ate

Xi

with y

and 2z carry out an additional effect on increasing the speed of implementation of the regulatory range of PR;

The drawing shows a diagram of a method for automatically limiting the EP bus.

The circuit contains a sensor 1 for the amount of power flow, a setpoint 2 for setting the limiter of the air flow, an element 3 for comparing the value of the flow with the setpoint, block 4 for adjusting the setpoint, block 5 for determining the pre-static stability of the electric motor, sensor 6 for incrementing the total power of the electric motor, sensor 7 for incrementing the mutual angle of the electric motor, unit 8 for generating a control action for changing the power of a RES, block .9 for distributing a control effect between a RES, a remote control channel 10 controlling a power plant 11, a block 12 for generating a control effect for a change in m OL generality, the distribution unit 13 control effect between ol, consumer-controller 14, the block 15, correction block transfer coefficients 12, a channel 16 transmission information receiving unit .1.7 unit 18 for determining correction limiting setpoint, increments the power determination section 19.

The flow restriction system operates as follows. ::

 The sensor 1 measures the power flow of the electric drive, the value of which is compared in element 3 with a predetermined value (limit setting), which forms the setter 2. The deviation of the transfer from the element 3 is supplied to the blocks. 8 and 12 of the development of control actions on RES and PR. The control action of block 8 is distributed between the individual RES 11 of block 9, the control action formed by block 12 is distributed between the individual PRs 14 of block 13. The values of the current values of the adjustment values for the AR are transmitted through channels 16

in block 17 receiving information. After checking the reliability of the values of the ranges PI (i f 1, l, p is the number of PR) are received in block 18, in which the value of the current dynamic range of regulation is calculated

. -:;:. P :

PR A Rpr 2 Ky A R | W kh

:: I 1. ; ..

reliability coefficient of execution of the control action of the flow limiter for changing the power of the 1st PR. Sq (

- coefficient of influence of power change of the 1st PR on power flow. .. In block 19, a determination of the increment of the power flow of EP A Rap Kv ARg in accordance with the value

5

YU

fifteen

twenty

25

thirty

35

40

45

fifty

55

of the calculated power imbalance А Ргi of the coefficient of the influence of this unbalance on the overflow Qw. The increment A Rap is calculated for the upcoming control time interval. At the output of block 19, a difference in parameters (DREp - A Ppr) is generated, which is input to the setpoint correction block 4. At the second input of this block, the value of the limit of static stability of the electric drive Ppr determined by block 5 is determined by the increments of the total power of the electric drive AS and the mutual angle Ab 12 between the voltage vectors at the starting and receiving U2 nodes. For small deviations of the EP mode from the initial value, the limit value can be determined by the expression Ppr3 UiU2yi2 A S / 12. Where yi2 is the mutual conductivity. Parameters AS and A (512 are recorded simultaneously by sensors 6 and 7....;

In block 1, the limit setting is determined by the expression -Pu (РПР-А Рн) / () - (А Rap-А: Рп), where Кн is the safety factor of the ES static stability in the set mode, and Рн is the amplitude of irregular flow fluctuations. Depending on the external conditions of the power system, the value of the coefficient Кн is taken equal. Kn 1.08-1.15, amplitude A PH 2; CiT / Pi, where Ci is the proportionality coefficient determined by the time of day PI is the power of the smaller of the connected power systems. The calculated setpoint value Ru is transmitted to setpoint 2.. .

According to the information on the magnitude of the EP loading and the rate of change of the mutual sliding about; in block 15, a control action is generated on changing the transmission coefficients of block 12, which controls the power of the PR. If the EP loading is such that the margin of stability is not lower than the normative one in the normal mode, then the Transfer coefficients of block 12 have minimum values. When the margin is lower than the normative (less than 20%) and transient intensity determined by the mutual sliding derivative a. Exceeding the given level a az / block 15, the transmission coefficients of block 12 are changed to ensure maximum speed of the PR power change. This is necessary to increase the intensity of suppression of flow deviations in the conditions of loading of electric drives with a safety factor Ki of 1.08 - 1.15.

So, the implementation of the proposed method allows to increase the use of transmission capacity due to the operational adjustment of the limit setting for the current values of the parameters of the mode of transmission, the magnitude of the adjustment range of the PR and the value of the calculated disturbance, the invention has been invented and a method for automatically limiting the flow of power transmission power, according to which measure the power flow by power transmission, compare it with the setpoint Ru, form the control effect on the change in power power plants and consumer regulators in the function of the deviation of the signal from the setpoint Ru and the value of the unbalance of the active power in the power supply system of the DRR, and, moreover, and in order to increase the use of transmission capacity, the increment of power flow is determined power transmission A Rap from the power imbalance A Rg in the expression A Rap Kvh x A Rg, where Kv is the coefficient of influence of the calculated power unbalance on the power flow, as well as the current dynamic range of regulation of consumer regulators by the expression

A RPR

1

1-1

KN | KB A Pi

5 0 5 0 5

0

where Kv is the coefficient of reliability of the execution of the control action of the flow limiter on the change in the power of the Ko consumer-controller;

Kv is the coefficient of influence of the power change of the 1st consumer-regulator on the power flow;

A Pi is the value of the adjustment range of the 1st consumer - controller; n is the number of consumer regulators, then the set point Ru is determined by expression.

Ru (Rpr A Rn) / (1 + Kn) - (A Rap - A Rpg),

where RPR is the limit of static stability of power transmission;

And Pk is the amplitude of unregulated flow fluctuations;

KN is the coefficient of the reserve of static stability of power transmission in the desired mode. when the overflow power exceeds the mouth of Ru, the value of the mutual sliding derivative a is determined, it is compared with the given value of az, and if the condition Saz is fulfilled, an additional effect is made to increase the speed of the implementation of the regulatory range of consumer regulators.