Ride-through alternatives of Adjustable Speed Drives (ASD's) during fault conditions

Abstract

Voltage unbalance or sag conditions generated by the power system faults can have a significant negative impact on the ASD's (Adjustable Speed Drives). A practical ride-through scheme based on supercapacitor/ battery as an energy storage device for ASD's is presented in this paper. Energy storage module is connected to support the DC -link voltage during power system faults. The performance of ASD's under normal and power system faults is first simulated in MATLab Simulink and then experimentally verified. The Data AcQuisition boards (DAQ) of National Instruments along with LabVIEW software have been used to record the observed waveforms.

Enhance Ride-Through Capability of Adjustable Speed Drives by Maintaining DC-Link voltage

“…Ultracapacitors offers many advantages for providing ride-through capabilities as given in Table.3 [15][16][17][18][19][20][21][22][23][24].…”

“…This technique is able to provide ride-through during an outage or during symmetrical or unsymmetrical. Hence, the ASD's remains in running mode during the disturbance [21][22][23][24].…”

Simulation of ride through capability of adjustable speed drive for type A and type B voltage sags and well using Buck-Boost converter

“…Nevertheless, the problem is of significance also in countries with a strong power grid [3]. Although there are number of power quality problems such as transients, interruption, sag/under voltage, swell/over voltage, waveform distortion, voltage fluctuations and frequency variations; voltage sag is a major reason for ASDs shutdown [4]. Voltage sag (dip) is a reduction between 10% and 90% in root-mean-square (rms) voltage, with duration between 0.5 cycles and 1 min [5].…”

Hybrid high-power rectifier with reduced THDI and voltage sag ride-through capability

“…a non-controlled six-pulse (Rect-l) and the ----�-�-----�-----------The ASD's are very sensitive equipment to voltage sags.It is noteworthy that the vast majority of outages of adjustable speed drives are related to voltage sags with a magnitude around 51 % to 65% of rated voltage[8] with duration around 3 and 30 cycles[9].Several studies have been conducted on the behavior of ASD's when subjected to voltage sags [10]-[12] and different alternatives have been proposed as solutions to increase the tolerance of ASD's under voltage sags[13] [15].In this context, in order to protect ASDs from voltage sags and thus prevent financial losses in industrial plants, the authors present a new front-end hybrid rectifier structure capable of imposing sinusoidal input line current in the AC system and providing voltage sag ride-through capability as well.III. OPERATING PRINCIPLEThe operation of the proposed converter depicted inFig.…”