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...
Power Quality Background A perfect electrical supply would deliver a constant frequency sinusoidal voltage waveform with unvarying magnitude. In daily work, power supplies deviate from this ideal situation because system loads vary and phenomena such as transients and outages may occur. If the power quality of the network is good, loads connected to it will run satisfactorily and efficiently. Insu...
Due to the rapid development of power electronic technology, the nonlinear characteristics of industrial and agricultural power loads, especially transportation and civil electrical products are becoming more and more serious, and the power factor of users is also declining. Therefore, reactive power compensation devices are more and more widely used. The power compensation device is used to suppl...