| 摘要 |
PURPOSE: Based on the correction set by the user, distance relay changes the correction of the grounding element for itself to the systemic situation to protect power transmission lines without failure. CONSTITUTION: Measure voltage and current from the place where the relay is installed. (the first step) Calculate the current impedance (ZA) from the measured voltage and current, (the second step), and calculate the load impedance (RL) from the calculated impedance (the third step). Calculate the total impedance (ZT) within the protection range defined by the user. (the fourth step) With load impedance and total impedance, calculate the impedance (RP) before the accident of the place where the relay is installed (the fifth stage). Calculate the resistance value (RR) and THETA from the impedance before the accident and change and store the protection area. (the sixth step). Check if the current impedance is in the protection area (the seventh step), if it is, trip the replay to protect the power transmission line (the eighth step). If it is not, proceed to the second step and repeat the above processes.
|
