Article

Harmonic Mitigation Using 12-Pulse AC–DC Converter in Vector-Controlled Induction Motor Drives

Dept. of Electr. Eng., Indian Inst. of Technol., New Delhi, India
IEEE Transactions on Power Delivery (Impact Factor: 1.73). 08/2006; 21(3):1483 - 1492. DOI: 10.1109/TPWRD.2005.860265
Source: IEEE Xplore

ABSTRACT

In this paper, a novel autotransformer with a reduced kilovolt-ampere rating is presented for harmonic current reduction in twelve-pulse ac-dc converter-fed vector-controlled induction motor drives (VCIMDs). Different transformer arrangements for 12-pulse-based rectification are also studied and a novel harmonic mitigator capable of suppressing fifth, seventh, and 11th (most dominant harmonics) in the supply current is presented. The design procedure for the proposed autotransformer is presented to show the flexibility in the design for making it a cost-effective replacement suitable for retrofit applications, where presently a six-pulse diode bridge rectifier is being used. The effect of load variation on VCIMD is also studied to demonstrate the effectiveness of the proposed harmonic mitigator. A set of power-quality indices on input ac mains and on a dc bus for a VCIMD fed from different 12-pulse ac-dc converters is given to compare their performance.

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Available from: Bhim Singh, Jun 11, 2014
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    • "Different techniques have been proposed for harmonic mitigation in the literature [4-26]. Although, in the conditions of light load or small source impedance, line current total harmonic distortion (THD) will be more than 5% for up to 24-pulse converters[7] [8] [9] [10] [11] [12] [13] [14]. For mitigating the total harmonic distortion (THD) problems observed in the input currents 30, 36 and 40-pulse converters are reported in [14- 25], But this topologies are high cost (cost is nearly doubled), increased complexity, and higher dc-link voltage due to boost operation. "
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    • "Basically, Harmonic cancellation in multi-pulse converters is accomplished via two or more paralleled bridge rectifiers in which their supplying voltages are phase shifted according to the desired output voltage pulse number. Various schematics of 12-pulse AC-DC converters have been proposed by researchers so far [4] [5] [6] [7] [8]. Although, these topologies do not meet the IEEE standard requirements for permissible harmonic distortion. "
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