Ik -----三相短路电流周期分量有效值，用来作为继电保护的整定计算

Ik ----- The effective value of the periodic component of the three-phase short-circuit current is used as the setting calculation of the relay protection and to verify the rated breaking current of the circuit breaker. The effective value of the periodic component of the three-phase short-circuit current when the short-circuit occurs at the installation of the relay protection (under the maximum operating mode of the power system) should be used to calculate the setting value of the protection device. <br>ish ----- Three-phase short-circuit impulse current, used to verify the dynamic stability of electrical equipment and bus. <br>Ish ----- Three-phase short-circuit steady-state effective value, used to verify the thermal stability of electrical equipment and bus. <br>S ----- Sub-transient three-phase short-circuit capacity, used to check the interrupting capacity of the circuit breaker and determine whether the bus short-circuit capacity exceeds the specified value, as the basis for selecting the current limiting reactor

Ik ----- three-phase short-circuit current cycle component valid value, which is used as a calibration calculation for relay protection and a rated open-off flow of the check circuit breaker. The fixed value of the protection device should be calculated by using the three-phase short-circuit current cycle component valid value (under the maximum operating mode of the power system) when a short circuit occurs at the relay protection installation. <br>the ish ----- three-phase short-circuit impact current, which is used to verify the dynamic stability of electrical equipment and bus lines. <br>Ish ----- three-phase short-circuit stable effective value, used to verify the thermal stability of electrical equipment and bus lines. <br>S----- temporary three-phase short-circuit capacity, used to verify the circuit breaker's break-out capacity and determine whether the bus short-circuit capacity exceeds the specified value, as the basis for selecting a current-limiting reactor

IK - effective value of periodic component of three-phase short-circuit current, used for setting calculation of relay protection and verification of rated breaking current of circuit breaker. The effective value of periodic component of three-phase short-circuit current in case of short circuit at the installation of relay protection (under the maximum operation mode of power system) shall be used to calculate the setting value of protection device.<br>Ish ------ three phase short-circuit impulse current, used to verify the dynamic stability of electrical equipment and bus.<br>Ish -- three phase short-circuit steady-state effective value, used to verify the thermal stability of electrical equipment and bus.<br>S-subtransient three-phase short-circuit capacity, used to verify the breaking capacity of the circuit breaker and judge whether the short-circuit capacity of the bus exceeds the specified value, as the basis for selecting the current limiting reactor<br>