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

1 OverviewCases of transformer oil contaminated by microorganisms have been reported both domestically and internationally. Individual transformer manufacturers, user units, and research institutions have conducted specialized studies, but all focused on power transformers. This paper targets specialty transformers for specific applications (e.g., rectifier transformers for graphitization furnaces, submerged arc furnace transformers), exploring the process of microbial contamination of their tra

1 Hardware Design of Tester Power SupplyThis device uses a standard small - signal generating device to generate small - current signals with the required frequency and phase angle. Then, through the amplifying circuit and phase - modulating circuit, the working power supply is generated.1.1 Power Frequency Sine Wave Small - Current Signal Generating DeviceThe sine wave generating circuit is mainly composed of the waveform generating chip MAX038 produced by MAXIM Corporation of the United States

1 Error Analysis of Traditional Turn Ratio Testing MethodsThe QJ35 turn ratio bridge and other single-phase-phase-based testers all use the double-voltmeter principle. The QJ35, however, eliminates power supply fluctuation interference via bridge balance. For three-phase transformer ratio testing with a single power supply, corresponding terminals must be shorted and data converted, turning three-phase tests into independent single-phase measurements, with √3 Yd conversion based on con

A certain special transformer manufacturing enterprise, which has been producing special transformers such as split - phase - shifting rectifier transformers, rectifier transformers for electrolysis, and transformers for submerged arc furnaces for more than 20 years. Now, an evaluation is made on the production process flow and its characteristics of the special transformers after the company's transformation.1.Production Process Flow Chart of Special TransformersThe production of special transf

Transformer Connection GroupThe connection group of a transformer refers to the phase difference between the primary and secondary voltages or currents. It is determined by the winding directions of the primary and secondary coils, the labeling of their start and end terminals, and the connection mode. Expressed in a clock-like format, there are 12 groups in total, numbered from 0 to 11.The DC method is commonly used to measure the transformer's connection group, mainly to verify whether the con

The sequence for shutting down a main transformer is as follows: when de-energizing, the load side should be shut down first, followed by the power supply side. For energizing operations, the reverse order applies: the power supply side is energized first, then the load side. This is because: Energizing from the power supply side to the load side makes it easier to identify the fault range and take prompt judgment and handling measures in case of a fault, preventing the fault from spreading or e

Let's take an auxiliary power system with two station transformers as an example. When one station transformer needs to be out of service, there are two operation methods: non-interruptive power supply and instantaneous power interruption. Generally, the method of instantaneous power interruption on the low-voltage side is preferred.The operation method for instantaneous power interruption on the low-voltage side is as follows: Open the 380V power incoming circuit breaker of the corresponding se

1. IntroductionEnergy is essential for societal operation and development. To meet national energy - conservation and emission - reduction policies, improving resource utilization—critical for power enterprises—is necessary. Multi - stage rural grid upgrades drive distribution transformer development. Despite high efficiency, widespread transformers still face significant overall losses due to capacity and usage issues; 70% of medium - and low - voltage grid losses come from

1 Relevant Theories of Small Neutral Point Reactors in 500kV Substations1.1 Definitions and RolesA reactor is a key power system component that controls the phase relationship between AC current and voltage, divided into inductive and capacitive types. Inductive reactors limit short-circuit currents and improve stability; capacitive ones enhance transmission efficiency and voltage quality. A small neutral point reactor is a specialized type connected between a three-phase system's neutral point

1 Technical Features and Standard References of 500kV Dry - type Shunt Reactors1.1 Technical FeaturesThe 500kV dry - type shunt reactor, an oil - free power device for ultra - high - voltage transmission systems, boasts core features like advanced insulation, innovative heat dissipation, optimized electromagnetic design, and modular structure. These advantages, outperforming traditional oil - immersed reactors, also drive new technical standard demands. Advanced Insulation: Using epoxy resin cas