Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

1. OverloadFirst, with the improvement of people's living standards, electricity consumption has generally increased rapidly. The original H59 distribution transformers have small capacity—“a small horse pulling a big cart”—and cannot meet user demands, causing the transformers to operate under overload conditions. Second, seasonal variations and extreme weather conditions lead to peak electricity demand, further causing H59 distribution transformers to run overloaded.Due to long-term overload o

H61 Distribution Transformer Selection includes the selection of transformer capacity, model type, and installation location.1.Selection of H61 Distribution Transformer CapacityThe capacity of H61 distribution transformers should be selected based on the current conditions and development trends of the area. If the capacity is too large, it results in the “large horse pulling a small cart” phenomenon—low transformer utilization and increased no-load losses. If the capacity is too small, the tran

Grounding the secondary neutral of a control transformer is a complex topic involving multiple aspects such as electrical safety, system design, and maintenance.Reasons for Grounding the Secondary Neutral of a Control Transformer Safety considerations: Grounding provides a safe path for current to flow to earth in the event of a fault—such as insulation failure or overload—instead of passing through the human body or other conductive paths, thereby reducing the risk of electric shock. System sta

Grounding Transformer Winding ConfigurationsGrounding transformers are classified by winding connection into two types: ZNyn (zigzag) or YNd. Their neutral points can be connected to an arc suppression coil or a grounding resistor. Currently, the zigzag (Z-type) grounding transformer connected via an arc suppression coil or a low-value resistor is more commonly used.1. Z-Type Grounding TransformerZ-type grounding transformers come in both oil-immersed and dry-type insulation versions. Among them

Why Do We Need a Grounding Transformer?The grounding transformer is one of the most important devices in power systems, primarily used to connect or isolate the system neutral point to ground, thereby ensuring the safety and reliability of the power system. Below are several reasons why we need grounding transformers: Prevent Electrical Accidents:During the operation of a power system, abnormal conditions such as voltage leakage may occur in equipment or lines due to various reasons. If the neut

How to Implement Transformer Neutral Grounding Gap Protection Measures?In a certain power grid, when a single-phase ground fault occurs on a power supply line, both the transformer neutral grounding gap protection and the power supply line protection operate simultaneously, causing an outage of an otherwise healthy transformer. The main reason is that during a system single-phase ground fault, the zero-sequence overvoltage causes the transformer neutral grounding gap to break down. The resulting

1.Innovative Winding Structures for 10 kV-Class High-Voltage High-Frequency Transformers1.1 Zoned and Partially Potted Ventilated Structure Two U-shaped ferrite cores are mated to form a magnetic core unit, or further assembled into series/series-parallel core modules. Primary and secondary bobbins are mounted on the left and right straight legs of the core, respectively, with the core mating plane serving as the boundary layer. Windings of the same type are grouped on the same side. Litz wire i

How to Increase Transformer Capacity? What Needs to Be Replaced for Transformer Capacity Upgrade?Transformer capacity upgrade refers to improving the capacity of a transformer without replacing the entire unit, through certain methods. In applications requiring high current or high power output, transformer capacity upgrades are often necessary to meet demand. This article introduces methods for transformer capacity upgrade and the components that need to be replaced.A transformer is a critical

Causes of Transformer Differential Current and Hazards of Transformer Bias CurrentTransformer differential current is caused by factors such as incomplete symmetry of the magnetic circuit or insulation damage. Differential current occurs when the primary and secondary sides of the transformer are grounded or when the load is unbalanced.Firstly, transformer differential current leads to energy waste. Differential current causes additional power loss in the transformer, increasing the load on the

1. System Configuration and Operating ConditionsThe main transformers at Zhengzhou Rail Transit’s Convention & Exhibition Center Main Substation and Municipal Stadium Main Substation adopt a star/delta winding connection with a non-grounded neutral point operation mode. On the 35 kV bus side, a Zigzag grounding transformer is used, connected to ground through a low-value resistor, and also supplies station service loads. When a single-phase ground short-circuit fault occurs on a line, a path