Active Front End Drives
The 6-pulse drive with Matrix AP harmonic filter outperformed the AFE drive in the following important areas: Harmonic performance under balanced line conditions: 2-9% better THID performance for loads 25-75% and similar performance (about 4% THID) at 100% load.
Harmonic performance under line imbalance conditions: Significantly better performance. For example, under 3% line voltage imbalances performance was 28.8% better (26.3% vs. 44.3% THID) at 25% load, and 6% better (12.3% vs. 18.3% THID) at 50% load.
Power Factor: Similar performance for loads 50-100%. Equal performance at 25% load and 3% voltage imbalance.* (*The Matrix AP harmonic filter exhibited a reduced leading power factor under light loads. While advantageous in some circumstances, a capacitor contactor option may be used to remove the filter capacitors from the circuit and eliminate this condition.)
Power Loss: The losses of a low horsepower AFE drive vs. a typical 6-pulse drive equipped with a Matrix AP filter is about 15%. However, the losses for a typical 1000 horsepower AFE vs. a 6-pulse drive with a Matrix AP filter drive are double.
A 6-pulse drive with a Matrix AP harmonic filter has a number of additional benefits over the AFE drive: smaller equipment size, lower price, shortened lead time, and increased availability of drives and corresponding replacement parts.
18-Pulse Drives
The 6-Pulse drive with Matrix AP harmonic filter outperformed the 18-pulse drive in the following technical specifications:
Power Loss Reduction: 40% – 73% depending on the size of the VFD and the component manufacturer.
Overall efficiency: 0.5% more efficient (99.0% vs. 98.5%).
Harmonic performance under balanced line conditions: 1-2% better THID performance for loads 25-75% and equal performance for loads greater than 75%.
Harmonic performance under line imbalance conditions: Significantly better performance. For example under 3% line imbalance, performance was 32.5% better (17.5% vs 50% THID) at 25% load and 13% better (12% vs 25% THID) at 50% load.
Power Factor: Better to equal performance for loads 50-100%.*
* The Matrix AP harmonic filter exhibited a reduced leading power factor under light loads. While advantageous in some circumstances, a capacitor contactor option may be used to remove the filter capacitors from the circuit and eliminate this condition.
A 6-pulse drive with a Matrix AP harmonic filter has a number of additional benefits over the 18-pulse drive: smaller equipment size and weight, lower price, and shortened lead time/increased availability of drives and corresponding replacement parts.