Electromagnetic compatibility test system

Voltage dips analysis is a complex stochastic issue, since it involves a large variety of random factors, such as: type of short circuits in the power system, location of faults, protective system performance and atmospheric discharges. Among all categories of electrical disturbances, the voltage dips (sags) and momentary interruptions are the nemeses of the automated industrial process. On the other hand, harmonic distortion is a steady state disturbance which is caused by the rectifier employed in adjustable speed drives, uninterruptible power supplies, electronic ballasts and other widely used energy-efficient technology. This paper describes a system for voltage dips testing according to IEC 61000–4–11 norm and it also test the supply current harmonic distortion according to the limits given in IEC 61000–3–2. The system equipment is described also with the test process. We use the created system to test the dip immunity of different topologies of PWM rectifiers and propose a new method of representing the results using power acceptability curves. The harmonic distortion is represented in a bar chart compared with the IEC 61000–3–2 limits.