Method for controlling active power distribution in power transmission lines and a controller for effecting same

A controller for controlling the active power flow distribution in a power transmission line comprising in combination:

• a. an active power flow transducer;
• b. a first setter for setting the value of active power flow to be distributed and maintained in the process of controlling;
• c. a first comparator having two inputs, one input thereof being connected to the output of said transducer for active power flow, the second input thereof being connected to the output of said first setter for active power flow;
• d. converter means connected to the output of said first comparator, for converting the difference between said actual and preset values of active power flow in the transmission line into nearest maximum extrapolated difference between the preset and actual values of active power flow;
• e. an adder connected to said first setter and to said convertor to obtain the sum of the nearest maximum extrapolated difference between the actual and preset values of active power flow thus obtained and the preset value of active power flow;
• f. a second setter for setting the permissible value of active power flow in the power transmission line to ensure stable operation of the power distribution system;
• g. a second comparator connected to said adder and said second setter for comparing the sum of the nearest maximum extrapolated difference between the actual and preset values of active power flow and the preset value of active power flow to said permissible value of active power flow in the power transmission line;
• and
• h. means connected to said second comparator for carrying out a proportional-plus-integral control of active power flow if said sum of the nearest maximum extrapolated difference between the actual and preset active power flow and the preset value of active power flow is greater than said permissible value of active power flow in said power transmission line, or alternately effecting an integral control of the active power flow if said sum of the nearest maximum extrapolated difference between, the actual and preset values of the active power flow and the preset value of actual power flow is smaller than said permissible value of active power flow in the said power transmission line.

A controller for controlling the active power flow distribution in a power transmission line comprising in combination:

• a. an active power flow transducer;
• b. a first setter for setting the value of active power flow to be distributed and maintained in the process of controlling;
• c. a comparator having two inputs, one input being connected to the output of said transducer for active power flow, the second input thereof being connected to the output of said first setter for active power flow;
• d. a second setter for setting the permissible value of active power flow in the power transmission line to ensure stable operation of the power distribution system;
• e. a logical unit having three inputs respectively connected to said comparator, said first setter and said second setter, said logical unit including extrapolation means for extrapolating the maximum difference between the actual and preset values of active power flow and including an adder for adding said extrapolated maximum difference to the output of said first setter;
• f. an integrator having an input connected to the output of said comparator;
• g. an amplifier having an input connected to the output of said comparator;
• h. a controlled gate having an input connected to the output of said amplifier and having a control input connected to the output of said logical unit;
• and
• i. an output adder having two inputs and an output, one input thereof being connected to the output of said integrator, the second input being connected to the output of said amplifier by way of said controlled gate, a control signal being formed at the output of said output adder which controls the distribution of active power flow in the power transmission line, said control signal effecting proportional-plus-integral control when the output of said adder of said logical unit exceeds said permissible value and effecting integral control when the output of said adder of said logical unit is less than said permissible value.