BenutzerhandbuchInhaltsverzeichnisXmath Model Reduction Module1Support2Worldwide Technical Support and Product Information2National Instruments Corporate Headquarters2Worldwide Offices2Important Information3Warranty3Copyright3Trademarks3Patents3WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS3Conventions4Contents5Chapter 1 Introduction8Using This Manual8Document Organization8Bibliographic References9Commonly Used Nomenclature9Conventions9Related Publications10MATRIXx Help10Overview10Functions11Figure 1-1. MRM Function11Table 1-1. MRM Restrictions12Nomenclature13Commonly Used Concepts14Controllability and Observability Grammians14Hankel Singular Values15Table 1-2. Calculating Hankel Singular Values16Internally Balanced Realizations17Singular Perturbation18Spectral Factorization20Low Order Controller Design Through Order Reduction22Figure 1-2. Low Order Controller Design for a High Order Plant22Chapter 2 Additive Error Reduction24Introduction24Truncation of Balanced Realizations25Reduction Through Balanced Realization Truncation27Figure 2-1. Different Approaches for Obtaining the Same Reduced Order Model28Singular Perturbation of Balanced Realization28Hankel Norm Approximation29balmoore( )31Related Functions34truncate( )34Related Functions34redschur( )35Algorithm35Related Functions37ophank( )37Restriction37Algorithm38Behaviors38Table 2-1. Orders of G39Onepass Algorithm41Multipass Algorithm43Discrete-Time Systems44Impulse Response Error45Unstable System Approximation46Related Functions46Chapter 3 Multiplicative Error Reduction47Selecting Multiplicative Error Reduction47Figure 3-1. Controller C(s) Designed for Multiplicative Error Reduction47Multiplicative Robustness Result48bst( )49Restrictions50Algorithm50Algorithm with the Keywords right and left51Securing Zero Error at DC54Hankel Singular Values of Phase Matrix of Gr55Further Error Bounds55Reduction of Minimum Phase, Unstable G55Imaginary Axis Zeros (Including Zeros at ∞)56Figure 3-2. Bilinear Mapping from G(s) to (Gs)(Case 1)57Figure 3-3. Bilinear Mapping from G(s) to (Gs)(Case 2)57Related Functions60mulhank( )60Restrictions60Algorithm60right and left61Consequences of Step 5 and Justification of Step 664Error Bounds66Imaginary Axis Zeros (Including Zeros at ∞)67Related Functions70Chapter 4 Frequency-Weighted Error Reduction71Introduction71Controller Reduction72Controller Robustness Result72Fractional Representations75Figure 4-1. Controller Representation Through Stable Fractions75Figure 4-2. C(s) Implemented to Display Right MFD Representation77Figure 4-3. C(s) Implemented to Display Left MFD Representation78Figure 4-4. Redrawn; Individual Signal Paths as Vector Paths79wtbalance( )80Table 4-1. Types versus Error Measures81Table 4-2. Error Measure Interpretation for wtbalance82Algorithm82Related Functions85fracred( )85Restrictions85Defining and Reducing a Controller86Figure 4-5. Internal Structure of Controller87Algorithm88Additional Background90Table 4-3. HSVs for an Eighth Order Controller91Related Functions91Chapter 5 Utilities92hankelsv( )92Related Functions93stable( )93Algorithm93Related Functions95compare( )95Chapter 6 Tutorial96Plant and Full-Order Controller96Figure 6-1. Loop Gain Constraints97Figure 6-2. Frequency Response for Plant, Compensator, and Compensated Plant99Controller Reduction100Figure 6-3. Open-Loop Gain Using redschur100Figure 6-4. Closed-Loop Gain with redschur102Figure 6-5. Step Response with redschur103ophank( )104Figure 6-6. Open-Loop Gain Using ophank104Figure 6-7. Closed-Loop Gain with ophank105Figure 6-8. Step Response with ophank106wtbalance107Figure 6-9. Open-Loop Gain with wtbalance108Figure 6-10. Closed-Loop Gain with wtbalance109Figure 6-11. Step Response with wtbalance110Figure 6-12. Frequency Response of the Weight V(jω)111Figure 6-13. Open-Loop Gain from wtbalance with "input spec"112Figure 6-14. System Singular Values of wtbalance with "input spec"113Figure 6-15. Step Response of wtbalance with "input spec"114fracred115Figure 6-16. Open-Loop Gain Using fracred115Figure 6-17. Closed-Loop Response with fracred116Figure 6-18. Step Response with fracred117Appendix A Bibliography119Appendix B Technical Support and Professional Services124Index125Symbols125A-F125G-S126T-W127Größe: 1,06 MBSeiten: 127Language: EnglishHandbuch öffnen