DSP BASED INTERSECTIONAL CONTROL IN MULTIDRIVE SYSTEMS M. Aníbal Valenzuela L., Jimmy Palma H., Ricardo Sanchez Sch. Dept. of Electrical Engg., University of Concepción Concepción - Chile

INTERSECTIONAL CONTROL DSP BASED SYSTEM ARCHITECTURE  THE COUNTER CARD IS FITTED WITH TWENTY COUNTERS AND A 5 MHZ CLOCK. IT IS DIRECTLY CONTROLLED BY THE PERSONAL COMPUTER WHICH COUNTS THE PULSES COMING FROM THE MOTOR ENCODERS  THE DSP PROCESSOR EXECUTES THE SPEED ESTIMATOR ALGORITHMS AND THE INTERSECTIONAL CONTROL ROUTINES. ALSO, IT MONITORS THE MOTOR CURRENTS AND GENERATES THE CONTROL VOLTAGE USING THE A/D -D/A CARD

DSP SPEED ALGORITHMS  METHODS OF SPEED ESTIMATION : TAYLOR SERIES EXPANTION SPEED ESTIMATOR (TSE) TAYLOR SERIES EXPANTION SPEED ESTIMATOR (TSE) LEAST -SQUARE FIT SPEED ESTIMATOR (LSF) LEAST -SQUARE FIT SPEED ESTIMATOR (LSF)  METHODS OF SPEED CALCULATION : PULSES COUNT DURING A PREDEFINED TIME PULSES COUNT DURING A PREDEFINED TIME TIME DURATION OF A SPECIFIED NUMBER OF PULSES TIME DURATION OF A SPECIFIED NUMBER OF PULSES CONSTANT ELAPSED TIME CONSTANT ELAPSED TIME

HYDRID DRIVE - SIMULATOR EXPERIMENTAL SYSTEM  THE CENTRAL SECTION AND THE 80% STEP LOAD DISTURBANCE ARE SIMULATED USING A DSP CARD  SECTIONS 1 AND 3 CORRESPOND TO THE FIRST AND LAST SECTIONS OF THE MECHANICAL SYSTEM  THIS ARRANGEMENT ALLOWS TO TEST THE DIFFERENT ALGORITHMS USING ALWAYS THE SAME STEP LOAD DISTURBANCE

DSP BASED INTERSECTIONAL CONTROL EXPERIMENTAL EVALUATION  CONTROL ALGORITHM INTERSECTIONAL CONTROL OF THE SPEED DIFFERENCE, PI - CONTROLLER INTERSECTIONAL CONTROL OF THE SPEED DIFFERENCE, PI - CONTROLLER  SPEED ALGORITHMS SPEED CALCULATION : PULSES COUNT DURING A PREDEFINED TIME, TIME DURATION OF A SPECIFIED NUMBER OF PULSES, CONSTANT ELAPSED TIME SPEED CALCULATION : PULSES COUNT DURING A PREDEFINED TIME, TIME DURATION OF A SPECIFIED NUMBER OF PULSES, CONSTANT ELAPSED TIME SPEED ESTIMATION : TAYLOR SERIES EXPANSION (TSE), LEAST - SQUARES FIT (LSF) SPEED ESTIMATION : TAYLOR SERIES EXPANSION (TSE), LEAST - SQUARES FIT (LSF)  INERTIA MODERATE INERTIA ( 10 J M ) MODERATE INERTIA ( 10 J M )  LOAD DISTURBANCE SEVERE ( 80 % ) SEVERE ( 80 % )

DSP BASED INTERSECTIONAL CONTROL EXPERIMENTAL EVALUATION DURING 80 % LOAD DISTURBANCE PULSES COUNT - LSF 1/4 SPEED ALGORITHM  TEST WAS PERFORMED USING THE HYBRID DRIVE - SIMULATOR EXPERIMENTAL SYSTEM  PULSE ENCODERS : 1024 ppr  SPEED CALCULATION : PULSES COUNT DURING A PREDEFINED TIME  SPEED ESTIMATION : LSF 1/4   max : 18.9 %

DSP BASED INTERSECTIONAL CONTROL EXPERIMENTAL EVALUATION DURING 80 % LOAD DISTURBANCE CONSTANT ELAPSED TIME SPEED ALGORITHM  TEST WAS PERFORMED USING THE HYBRID DRIVE - SIMULATOR EXPERIMENTAL SYSTEM  PULSE ENCODERS : 1024 ppr  SPEED CALCULATION : CONSTANT ELAPSED TIME (CET)  SPEED ESTIMATION : NOT USED   max : 10.8 %

DSP BASED INTERSECTIONAL CONTROL EXPERIMENTAL EVALUATION DURING 80 % LOAD DISTURBANCE TIME DURATION OF PULSES SPEED ALGORITHM  TEST WAS PERFORMED USING THE HYBRID DRIVE - SIMULATOR EXPERIMENTAL SYSTEM  PULSE ENCODERS : 1024 ppr  SPEED CALCULATION : TIME DURATION OF A SPECIFIED NUMBER OF PULSES  SPEED ESTIMATION : NOT USED   max : 8.0 %

DSP BASED INTERSECTIONAL CONTROL SUMMARY

DSP BASED INTERSECTIONAL CONTROL CONCLUSIONS  DURING SEVERE LOAD DISTURBANCES IN MULTIDRIVE SYSTEMS, THE LOSS OF SYNCHRONIZATION MIGHT PRODUCE SEVERE STRIP STRESSES, STRIP BREAKS OR DRIVE OVERLOAD  THE ADDITION OF AN INTERSECTIONAL CONTROL ALLOWS TO REDUCE SIGNIFICANTLY THE MAXIMUM ANGULAR DEVIATION (  max ) DURING SEVERE LOAD DISTURBANCES  THE PERFORMANCE OF THE INTERSECTIONAL CONTROL IS HIGHLY DEPENDENT ON A FAST AND ACCURATE DETERMINATION OF THE MOTOR SPEEDS. THE BEST RESULTS WERE OBTAINED USING THE CONSTANT ELAPSED TIME (CET) AND THE MEASUREMENT OF TIME DURATION OF A NUMBER OF PULSES METHODS  THE DSP BASED ARCHITECTURE ALLOWS TO OBTAIN A GOOD CONTROL PERFORMANCE. USING PI-CONTROLLER AND CONSIDERING MODERATE INERTIA SECTIONS, THE MAXIMUM ANGULAR DEVIATION WAS REDUCED TO 8%, SIMILAR TO THE THEORETICAL VALUE