In the vast and intricate operational framework of modern power systems, current transformers (CTs), as pivotal electrical devices, play an irreplaceable role. Their application scenarios are extensively distributed across all aspects of power systems.
1. Power Metering Scenario
In the domain of power metering, current transformers serve as core components for precise electricity measurement. Whether in power plants, substations, or in front of end - user meters, CTs are omnipresent. They convert the high - magnitude primary current in power systems into a reduced - scale secondary current at a fixed ratio. This enables metering equipment to measure and calculate electrical energy safely and accurately. For instance, in residential distribution boxes, CTs transform the high - amperage currents in circuits into low - amperage values suitable for meter readings. Power supply companies then accurately calculate user power consumption based on the meter - recorded data, ensuring equitable billing. The utilization of CTs in power metering scenarios offers reliable data support for power trading and cost accounting, thereby ensuring the orderly operation of the power market.
2. Relay Protection Scenario
Current transformers act as the "eyes" of relay protection systems. When faults such as short circuits or overloads occur in power systems, the line current surges instantaneously. CTs can promptly detect these abnormal current fluctuations and transmit the modified current signals precisely to relay protection devices. These devices determine the nature and location of the faults based on the received signals and subsequently act swiftly to isolate the faulty lines, preventing the spread of faults and safeguarding the safe and stable operation of electrical equipment and the entire grid. In substation relay protection systems, CTs are strategically installed at key line nodes to continuously monitor current conditions. Upon detecting anomalies, they trigger protective actions, thus averting equipment damage and power outages. In essence, CTs form the cornerstone of power system relay protection and stand as the first line of defense for grid security.
3. Operation Monitoring and Control Scenarios
In the operation monitoring and control segments of power systems, current transformers also assume a crucial role. Power dispatch centers require real - time access to the operational parameters of all power system components. CTs convert line current information and transmit it to dispatch centers via communication systems, supplying dispatchers with accurate current data. Leveraging this data, dispatchers can analyze and assess the grid's operational status, allocate power resources rationally, and optimize grid operation modes. Moreover, in the automatic control of electrical equipment, the current signals provided by CTs serve as essential references for equipment actuation. For example, in automatic reactive power compensation devices, CTs continuously monitor line currents and control the activation or deactivation of compensation equipment according to current variations, achieving dynamic reactive power balance and enhancing the power factor and operational efficiency of the power system. The application of CTs in operation monitoring and control scenarios provides robust support for the intelligent and efficient operation of power systems.
From power metering to relay protection and operation monitoring and control, current transformers permeate all critical links of power systems. With their stable and reliable performance, they play distinctive and indispensable roles in diverse application scenarios, laying a solid foundation for the secure, stable, and efficient operation of power systems.