What are the precautions for live oil filtration? (1) Throughout the entire process of live oil filtration and degassing, the gas relay circuit of the transformer must be connected to the signal circuit to prevent gas leakage and oil running in the pipeline, causing the oil switch to trip and resulting in a large-scale power […]
How are the deviation values of transformer parameters and the parameters using peak values specified? The specifications for evaluating the performance parameters of transformers are determined by technical conditions, and each standard value has corresponding deviation values, which can be categorized into several types: (1) Parameters with only a lower limit specified, without an upper
How is the testing of transformer oil conducted? The dielectric strength test of transformer oil is conducted using a 500mm³ standard oil cup in a 60kV AC frequency oil tester. The brass electrodes of the oil cup have a diameter of 25mm, and the surface cleanliness is as shown in Figure 92—6, with an electrode
How is the measurement of insulation resistance and absorption ratio conducted? Insulation resistance, denoted as R, is typically determined by applying a voltage of 2500V for 60 seconds and measuring the resulting value using a megohmmeter with a maximum range of 10000 MQ. Due to variations in the stability of insulation resistance arising from differences
What is the basic concept of overvoltage? In the operation of various electrical equipment in power systems, besides withstanding normal system voltages, they also encounter various types of overvoltages. Overvoltages are generally classified into two categories based on their sources: external overvoltages and internal overvoltages. External overvoltages typically refer to lightning-induced overvoltages. Internal overvoltages refer
Yyy connection：What are the characteristics ? The Yyy connection exhibits third harmonic voltage, but in three-phase three-legged core transformers, the third harmonic voltage does not exceed 5% of the fundamental. Therefore, it is suitable only for three-phase three-legged core medium to large transformers and cannot be used for three-phase five-legged transformers. Contact LuShan, est. 1975,
Yyd and Ydd Connection : What are the characteristics? The Yyd connection is suitable for transformers with various core configurations, and its features include: (1) The adoption of d-shaped winding on the low-voltage side allows for the elimination of third harmonic voltage. (2) The d-shaped winding can serve as the main winding for power transmission
How does humidity affect the operation of transformers? Relative humidity is expressed as a percentage at a certain temperature. At high temperatures, if the relative humidity is high, it is prone to the proliferation of mold. These molds may have adverse effects on the paint on the surface of the transformer tank. Additionally, in situations
Yd and Dy Winding Configurations: What are the characteristics? The Yd winding configuration is suitable for transformers with various core forms and features: a. The third harmonic current can circulate through the secondary side, eliminating the third harmonic voltage. b. The neutral point on the primary side can be grounded; since the secondary side adopts
What is the winding configuration of a transformer? The combination of the connection methods for the high, medium, and low voltage windings of a transformer is referred to as the winding configuration. The winding configuration is crucial for the performance, manufacturing cost, and operational characteristics of the transformer. Common winding configurations for dual-winding three-phase
