6~20kV Substation low voltage commonly used main wiring（One transformer）
Master Electrician
09/25/2024
6~20kV Substation low voltage commonly used main wiring（One transformer）
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The grounding resistance of the box transformer is usually required to be ≤ 4Ω. Do you know why?
As a key power distribution equipment, the safe operation of a compact substation relies on reliable grounding measures. People often wonder: Why is the grounding resistance of a compact substation generally required to be no more than 4Ω? Behind this value, there are rigorous technical bases and application scenario restrictions. In fact, the requirement of ≤4Ω is not mandatory in all cases. It mainly applies to scenarios where the high - voltage system adopts "ungrounded", "reso
Edwiin
07/23/2025
What are the common overvoltages in the distribution network?
Distribution networks, characterized by their wide distribution, large number of equipment, and low insulation level, are prone to insulation accidents caused by overvoltage. This not only reduces the stability of the entire distribution system and the insulation performance of the lines but also has a significant adverse impact on the safe operation of the power grid and the healthy and sustainable development of the power industry.From a circuit perspective, apart from the power source, the po
Leon
07/21/2025
Analysis of the Principle of Second - harmonic Restraint for Overcurrent Protection of Distribution Automation Switches
Substance of Second - harmonic Restraint in Overcurrent ProtectionThe substance of second - harmonic restraint in overcurrent protection is to use the second - harmonic component to judge whether the current is a fault current or an excitation inrush current. When the percentage of the second - harmonic component to the fundamental - wave component is greater than a certain value, it is judged to be caused by the excitation inrush current, and the overcurrent protection is blocked.Therefore, the
Leon
07/18/2025
What are the typical connection methods for 35kV distribution lines?
Typical Wiring Diagram of 35kV Line Radial π ConnectionWhen a 35kV line adopts a radial power grid structure, a single - side power supply or a double - side power supply radial type can be used according to the situation of the power supply points, and a loop - out interval is reserved at the end of the line.Typical Wiring Diagram of 35kV Line Radial T - ConnectionFor double - radial lines, it is advisable to select a double - side power supply. When the power supply points do not meet the r
Leon
07/18/2025
