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

Why Does the Transformer Core Need to Be Grounded?During operation, the transformer core, along with the metal structures, parts, and components that fix the core and windings, are all situated in a strong electric field. Under the influence of this electric field, they acquire a relatively high potential with respect to ground. If the core is not grounded, a potential difference will exist between the core and the grounded clamping structures and tank, which may lead to intermittent discharge.I

I. What is a Neutral Point?In transformers and generators, the neutral point is a specific point in the winding where the absolute voltage between this point and each external terminal is equal. In the diagram below, pointOrepresents the neutral point.II. Why Does the Neutral Point Need Grounding?The electrical connection method between the neutral point and earth in a three-phase AC power system is called theneutral grounding method. This grounding method directly affects:The safety, reliabilit

Single-phase grounding, line break (open-phase), and resonance can all cause three-phase voltage unbalance. Correctly distinguishing among them is essential for rapid troubleshooting.Single-Phase GroundingAlthough single-phase grounding causes three-phase voltage unbalance, the line-to-line voltage magnitude remains unchanged. It can be classified into two types: metallic grounding and non-metallic grounding. Inmetallic grounding, the faulted phase voltage drops to zero, while the other two phas

Composition and Working Principle of Photovoltaic (PV) Power Generation SystemsA photovoltaic (PV) power generation system is primarily composed of PV modules, a controller, an inverter, batteries, and other accessories (batteries are not required for grid-connected systems). Based on whether it relies on the public power grid, PV systems are divided into off-grid and grid-connected types. Off-grid systems operate independently without relying on the utility grid. They are equipped with energy-s

1. On a scorching sunny day, do damaged vulnerable components need to be replaced immediately?Immediate replacement is not recommended. If replacement is necessary, it is advisable to do so in the early morning or late afternoon. You should contact the power station’s operation and maintenance (O&M) personnel promptly, and have professional staff go to the site for replacement.2. To prevent photovoltaic (PV) modules from being hit by heavy objects, can wire mesh protective screens be install

1. What are the common faults of distributed photovoltaic (PV) power generation systems? What typical problems may occur in various components of the system?Common faults include inverters failing to operate or start due to voltage not reaching the startup set value, and low power generation caused by issues with PV modules or inverters. Typical problems that may occur in system components are burnout of junction boxes and local burnout of PV modules.2. How to handle common faults of distributed

One of the main differences between a short circuit and an overload is that a short circuit occurs due to a fault between conductors (line-to-line) or between a conductor and earth (line-to-ground), whereas an overload refers to a situation where equipment draws more current than its rated capacity from the power supply.Other key differences between the two are explained in the comparison chart below.The term "overload" typically refers to a condition in a circuit or connected device. A circuit

Leading and lagging power factors are two key concepts related to the power factor in AC electrical systems. The main difference lies in the phase relationship between current and voltage: in a leading power factor, the current leads the voltage, whereas in a lagging power factor, the current lags behind the voltage. This behavior depends on the nature of the load in the circuit.What is Power Factor?Power factor is a crucial, dimensionless parameter in AC electrical systems, applicable to both s

Electromagnets vs. Permanent Magnets: Understanding the Key DifferencesElectromagnets and permanent magnets are the two primary types of materials that exhibit magnetic properties. While both generate magnetic fields, they differ fundamentally in how these fields are produced.An electromagnet generates a magnetic field only when an electric current flows through it. In contrast, a permanent magnet inherently produces its own persistent magnetic field once it has been magnetized, without requirin

The power outage and work scopes must be clearly inspectedCollaborate with the site survey leader to confirm the equipment to be maintained and the work area involved. Consider requirements such as the use of special vehicles and large machinery, and safe distances from adjacent energized equipment. Verify on-site whether the proposed power outage scope is sufficient to meet the operational needs.On-site safety measures must be clearly inspectedCollaborate with the site survey leader to verify s