METHOD OF DETERMINING STATIC STABILITY MARGIN OF ELECTRIC NETWORK LOAD NODE WITH INDUCTION MOTORS Russian patent published in 2017 - IPC H02H7/08 H02J3/18 H02J3/24 

FIELD: electricity.

SUBSTANCE: in the method, periodic measurements of the load operating parameters are made at the node of its connection or from the side of the feeding node. At the current time, according to the equations of interrelation between the operating parameters and the parameters of the equivalent circuits for the set of modes of operation of the load node, feeding node, formed both from the operation modes of the load node with their natural variation, and with artificially created changes by significant unloading of the electric motors, the voltage variations in the supply node determine the parameters of the equivalent circuits for induction motors, nodes of complex load, power supply network. According to the known parameters of the current mode and the equivalent circuit of the electrical network with the load node, the critical slip of the electric motor or equivalent electric motor for the group of electric motors is calculated, the limiting voltage and power of the motor, the load node or the voltage of the supply node, the reserve coefficients for voltage and power, and, if the unallowable reduce of set reserves on voltage or active power, reduce the load of induction motors or influence on the means of increasing the voltage and carry out shutdown of a part of the load to prevent violation of the static stability mode of induction motors.

EFFECT: increasing the accuracy of determining the static stability of load nodes of electric networks with induction motors, the possibility of determining them with unknown parameters of the equivalent circuits for motors and electric networks, preventing the violation of stability of the electric motor modes.

1 tbl, 12 dwg