How are three-phase current transformers used in power protection systems?
DASN series three-phase current transformers play a key role in power protection systems, mainly by monitoring and measuring three-phase current to achieve protection of power systems. Specifically, the functions of DASN series three-phase current transformers include the following aspects:
Current measurement:
Current transformers convert high currents into lower, measurable currents for use by protection devices and measuring instruments.
By measuring three-phase currents, the operating status of the power system can be monitored in real time to ensure that the current operates within a safe range.
Overcurrent protection:
When the current exceeds the preset value, the current transformer transmits a signal to the protection relay or circuit breaker to quickly cut off the power supply to prevent equipment damage and fire and other dangerous situations.
Differential protection:
DASN series three-phase current transformers are used for differential protection of transformers, generators and transmission lines. They detect internal faults by comparing the current difference at both ends of the protection area.
If a short circuit or other fault occurs in the protection area, the differential protection device will start and quickly isolate the faulty part.
Direction protection:
Direction protection is to determine the direction of the fault current through the cooperation of current transformer and voltage transformer, so as to determine the location of the fault point.
This protection method is particularly important in complex power grid structures, which helps to quickly locate faults and take corresponding measures.
Distance protection:
In the transmission line, the DASN series three-phase current transformer is used in conjunction with the voltage transformer to achieve distance protection. By measuring the fault current and voltage, the distance from the fault point to the protection device is calculated.
Distance protection can quickly identify faults and isolate the fault section, reducing the scope and time of power outages.
Current unbalance protection:
In a three-phase system, if current imbalance occurs, the current transformer can detect the difference in current between phases, trigger the protection device, and prevent the equipment from being damaged by unbalanced current.
These functions of the DASN series three-phase current transformer jointly ensure the safe and stable operation of the power system, prevent the occurrence of various electrical faults, and ensure the reliability of the power system.
