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

Summary of Issues Related to Distribution Network Grounding Resistance Threshold and CalculationIn the operation of the distribution network, the insufficient ability to identify the grounding resistance is a key issue affecting fault judgment. To reasonably set the threshold, multiple factors need to be comprehensively considered.I. Difficulties and Directions in Balancing ThresholdsThe operating conditions of the grounding resistance are extremely complex. The grounding media may include tree

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

Analysis of Partial Discharge Principle (1)Under the action of an electric field, in an insulation system, discharge occurs only in some regions and does not penetrate between the conductors with the applied voltage. This phenomenon is called partial discharge. If partial discharge occurs near a conductor surrounded by gas, it can also be called corona.Partial discharge can occur not only at the edge of a conductor but also on the surface or inside an insulator. The discharge occurring on the su

According to the type of connection FACTS Controller with the power system, it is classified as; Series Connected Controller Shunt Connected Controller Combined Series-Series Controller Combined Shunt-Series ControllerSeries-Connected ControllersSeries controllers introduce a voltage in series with the line voltage, typically using capacitive or inductive impedance devices. Their primary function is to supply or absorb variable reactive power as needed.When a transmission line is heavily loaded,

FACTS (Flexible Alternating Current Transmission System) refers to a power electronics-based system that uses static devices to enhance the power transfer capability and controllability of AC transmission networks.These power electronic devices are integrated into conventional AC grids to boost key performance metrics, including: Power transfer capacity of transmission lines Voltage stability and transient stability Voltage regulation precision System reliability Thermal limits of transmission i

Difference Between HVAC and HVDCElectricity generated in power plants is transmitted over long distances to electrical substations, which then distribute it to consumers. The voltage used for long-distance power transmission is extremely high, and we will explore the reasons for this high voltage later. Additionally, the transmitted power can be in either alternating current (AC) or direct current (DC) form. Therefore, power can be transmitted using either HVAC (High Voltage Alternating Current)

What are the Advantages of HVDC over HVAC?Electricity travels long distances before reaching consumers. Power plants, often remote, supply electricity through hundreds of miles and multiple substations. High-voltage transmission reduces line losses, with both AC and DC used. Though AC is familiar via utility poles and home outlets, HVDC offers unique advantages in power transmission.The goal of power transmission is to minimize losses and costs. While both face influencing factors, HVDC has more

Neutral - Point Grounding Modes and Protection of Transformers in Power GridsFor systems ranging from 110 kV to 500 kV, an effective grounding method shall be adopted. Specifically, under all operating conditions, the ratio of zero - sequence reactance to positive - sequence reactance X0/X1 of the system should be a positive value and not exceed 3. Meanwhile, the ratio of zero - sequence resistance to positive - sequence reactance R0/X1should also be a positive value and not exceed 1.In 330 kV a

Definition: An energy meter is a device used to measure the electrical energy consumed by an electrical load. Electrical energy refers to the total power consumed and utilized by a load over a specific period of time. Energy meters are used in domestic and industrial AC circuits to measure power consumption. They are relatively inexpensive and accurate.Construction of an Energy MeterThe construction of a single - phase energy meter is shown in the figure below.The energy meter consists of four m

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