What is the role of Power Current Transformer in the power system?

1. Measuring current
Accurate measurement: The current in the power system is usually very large. Direct measurement is not only unsafe, but also difficult for general measuring instruments to withstand such a large current. Power Current Transformer can accurately convert the large current on the primary side into a small current on the secondary side in proportion, generally with standard values ​​such as 5A or 1A, so that measuring instruments such as ammeters can conveniently and safely measure the current, thereby accurately obtaining the current size of each branch and each device in the power system, and providing accurate data support for the operation monitoring and analysis of the power system.
Electric energy metering: Used in conjunction with the electric energy meter, the Power Current Transformer converts the large current into a small current suitable for the electric energy meter to measure, so as to achieve accurate measurement of electric energy. Accurate electric energy metering is an important basis for power companies to settle electricity bills, manage energy, and for users to understand their own electricity consumption. It is of great significance to ensure fair transactions and reasonable electricity consumption in the power market.
2. Protect the safety of the power system
Fault detection: When short circuits, overloads and other faults occur in the power system, the fault current will increase sharply. The Power Current Transformer can detect this change in a timely and accurate manner, and convert the fault current into a signal on the secondary side in proportion, and transmit it to the relay protection device. According to the received current signal, the relay protection device can quickly determine the type and location of the fault, thereby timely triggering the corresponding protection action, such as tripping to cut off the fault circuit, etc., effectively preventing the expansion of the fault range and protecting the safe and stable operation of the power equipment and the entire power system.
Guarantee of the sensitivity and reliability of the protection device: Since the Power Current Transformer can accurately reflect the changes in the primary current, it provides a reliable current signal for the relay protection device, so that the protection device can act quickly and accurately at the moment of the fault, improving the sensitivity and reliability of the protection device. This is crucial to ensure the continuous power supply of the power system and reduce the power outage time caused by faults.
3. Monitoring the operating status of power equipment
Load monitoring: By measuring the current size of different equipment, the load status of the power equipment can be understood in real time. According to the trend and size of the current change, it can be judged whether the equipment is in normal operation and whether there are abnormal conditions such as overload and underload. This helps power operators to adjust the operation mode of the equipment in time, optimize the load distribution of the power system, improve the utilization rate and operation efficiency of power equipment, and extend the service life of the equipment.
Fault diagnosis: In addition to providing signals to protection devices when faults occur, the current data measured by Power Current Transformer in daily operation can also be used for fault diagnosis of power equipment. Through long-term monitoring and analysis of current data, combined with other operating parameters, potential fault hazards of equipment, such as insulation aging, poor contact, etc., can be discovered, so that measures can be taken in advance for repair or replacement to avoid faults and improve the reliability and safety of the power system.
4. Realize automatic control of power systems
Provide signals for automation devices: In modern power systems, various automatic control devices are widely used, such as substation automation systems and power grid dispatching automation systems. Power Current Transformer provides key current signals for these automation devices, so that the automation devices can monitor the operating status of the power system in real time according to the changes in current, realize remote control, automatic adjustment and fault warning of power equipment, and improve the automation level and operation management efficiency of the power system.
Cooperate with other equipment to realize protection and control functions: Power Current Transformer cooperates with other power equipment such as voltage transformers and circuit breakers to form a protection and control system for the power system. For example, in differential protection, by comparing the current difference between the current flowing into and out of the device measured by the current transformer, it is determined whether the device has an internal fault, thereby achieving rapid and selective protection of the power equipment. This collaborative working method ensures that the power system can operate safely and stably under various working conditions.