Three-phase lines are common: three-phase three wire, three-phase four wire The three - phase three - wire system is star connection neutral point ungrounded and Angle connection method, the general high - voltage power supply uses three - phase three - wire system, three - phase four - wire is star connection neutral point grounding, low - voltage system uses three - phase four - wire system. &nb...
Effect of Poor Power Factor The major effect of poor power factor is higher value of line current. We know that power factor (pf) is an important parameter for calculation of power in an AC circuit. For a given power and voltage, the current flowing through the line is inversely proportional to the power factor. This means that a poor power factor i.e. low power factor will result in hig...
3 phase load current imbalance In three phase systems, current unbalance is defined as the maximum deviation of any phase current from average divided by average current. Current unbalance can occur due to reasons within the control of the end user or outside the control of end user. Some of the reasons for current unbalance (or imbalance) are: Source voltage from the electric utility is unbalance...
Research background Because the value of harmonic loss is smaller than that of fundamental loss and the calculation is difficult, it is generally ignored in the theoretical calculation of line loss. However, with the development of power electronics technology, the nature of power generation and electrical equipment is becoming increasingly complex, and various nonlinear components put into ...
With the development of society and the increase of demand for electricity, Reactive power compensation technology has developed rapidly, including Static VAR Compensation and Dynamic Reactive Power compensation, and has gained rich operating experience. However, some problems have also been exposed in practice. Some reactive power compensation devices are inconvenient to move, and the equipment m...
What is EMC testing EMC test (Electro Magnetic Compatibility) refers to the comprehensive evaluation of electromagnetic interference (EMI) and anti-interference capability (EMS) of electronic products. It is one of the most important indicators of product quality. The measurement of electromagnetic compatibility consists of test sites and test instruments. The purpose of EMC test is ...
The utility model patent discloses an Enhanced Active Power Filter with a three-phase unbalance adjustment function. The IGBT converter of the Enhanced Active Power Filter is a three-level three-phase four-wire four-arm PWM transformer. The fourth bridge arm is connected in parallel with the remaining three bridge arms, and the midpoint of the fourth bridge arm is connected to the neutra...
The existing power grid is usually equipped with a large number of nonlinear electronic components. These nonlinear electronic components will generate corresponding harmonics during the working process, among which high-order harmonics will interfere with the electrical equipment in the power grid and seriously affect the power supply. Power quality in the grid. In order to reduce the adverse eff...