Harmonic analysis and performance improvement of slip energy recovery induction motor drives

Abstract

Slip energy recovery induction motor drives are used in high power applications, in which by controlling the slip power a variable speed drive system is provided. However, poor power factor is a disadvantage of the system. Presence of sub-harmonics of the line frequency on the stator side is one of the special features of these drives. Phase-controlled inverter can absorb the reactive power from the supply and inject the low-order current harmonics with relatively high amplitudes to the supply. This paper simulates the harmonic content of waveforms in various points of drive at different speeds, based on the hybrid model (dqabc). Then the sinusoidal pulse-width-modulation (SPWM) control technique is used in order to improve the power factor of the drive and to weaken the injected low-order harmonics to the supply. Based on the frequency spectrum, total harmonic distortion, distortion factor and power factor, two phase control and SPWM techniques are compared and the advantage of the SPWM technique over the phase control technique is shown.Index Terms-Harmonic analysis, slip energy.

Harmonics Analysis in Various PWM Inverters Using the Fish Method

“…To this end, the fish method is originally applied to analyze the harmonics in voltage space vector pulsewidth modulation (VSV-PWM) [6,7] the motor performance in VSV-PWM inverter is superior to that in S-PWM inverter. The results are also verified by the well-known total harmonic distortion (THD) [8][9][10] analysis.…”

Novel Scheme to Improve Power Factor of Slip Energy Recovery Drive by Selective Harmonic Elimination

“…The drive power factor is found to be optimized for applications requiring a narrow range of speed control and a large load torque, where significant real power is returned via the inverter [9]. It is well known that the power factor of the SERD is poor at the lower end of the speed range [9,10]. In this paper, a simulation model of self commutated SERD using IGBT inverter is developed and further modified to investigate the drive power factor.…”

Hybrid Passive Filter Design for Distribution Systems with Adjustable Speed Drives

“…Electric utilities are very concern about the fast growth of large electric drives in the industrial sectors of distribution system. Variable frequency and PWMI drives are considered as one of the biggest contributors to power quality problems due to their high-power ratings [1][2][3]. The nonlinear v-i characteristics of drive systems may result in triplen harmonic currents, neutral conductor problems (and increased losses), transformer saturation (and overheating), power-factor capacitor failures, unsatisfactory performance of fuses, circuit breakers and relays (e.g., longer or shorter tripping times depending on the harmonic magnitude and spectrum), etc.…”