{'fraction_non_alphanumeric': 0.011398963730569948, 'fraction_numerical': 0.0, 'mean_word_length': 6.0, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Controller reduction using optimal Hankel norm approximation with guaranteed closed-loop performance

The present work deals with the problem of frequency weighted controller reduction using optimal Hankel norm approximation. The advanced controller designs methods like LQG/LTR or H∞ based synthesis methods leads to controllers of order comparable to the plant and sometimes unstable controller whereas lower order controller should be sought out to keep the closed-loop stability and system performance within acceptable limit. For unstable controller reduction a controller decomposition algorithm is developed using two stage transformations. The algorithm discussed for computation of balancing transform is based on orthogonal transformation which circumvents the ill-conditioned cases due to numerical errors. Resulting closed-loop system with reduced order controller is guaranteed to preserve the dominant time domain and frequency domain characteristics.