THIS PAPER PRESENTS A 27-LEVEL ASYMMETRIC MULTILEVEL SHUNT ACTIVE POWER FILTER TOPOLOGY THAT ALLOWS THE COMPENSATION OF A NONLINEAR LOAD, AS WELL AS THE DC VOLTAGE REGULATION THANKS TO A COMPREHENSIVE CONTROL STRATEGY. THE TOPOLOGY CONSIDERS THE RATIO 9?3?1 IN ORDER TO GENERATE THE AC WAVEFORM WITH A SIMPLE STAIRCASE MODULATION ALGORITHM. THE DYNAMIC MODEL OF THE PROPOSED TOPOLOGY IS OBTAINED AND VALIDATED WITH A SIMPLE OPEN LOOP SIMULATION. A SUITABLE LINEAR MASTER-SLAVE CONTROL SCHEME IS PRESENTED IN ORDER TO ENSURE THE CURRENT TRACKING AND THE DC VOLTAGE REGULATION. THE PROPERNESS OF THE PROPOSAL IS VERIFIED TROUGH DYNAMIC AND STATIONARY TESTS.

MULTILEVEL INVERTERS ARE THE ALTERNATIVE FOR MEDIUM VOLTAGE APPLICATIONS. WITHIN THIS TYPE OF INVERTERS ARE THE ASYMMETRIC INVERTERS, WHICH HAVE DIFFERENT VALUES IN THEIR DC VOLTAGES. THE DC VOLTAGE RATIOS CAN BE OF THE TRINARY OR BINARY TYPE, THE FIRST BEING THE MOST DOCUMENTED, WITH WHICH AN AC VOLTAGE OF 3 N = 27 LEVELS IS OBTAINED, USING N = 3 INVERTERS IN CASCADE AND NLM MODULATION, WHICH GENERATES A FLOW OF POWER FROM THE LOAD TO THE INVERTERS (REGENERATION). IN THIS PAPER WE ANALYZE TWO TYPES OF NON-REGENERATIVE SINGLEPHASE ASYMMETRIC INVERTERS, OF 15 AND 27 LEVELS, WHERE THEIR QUALITY OF OUTPUT VOLTAGE WAVEFORM (THD) AND EFFICIENCY ARE ANALYZED. THE LATTER WILL BE FOCUSED ON THE COMMUTATION AND CONDUCTION LOSSES IN THE SEMICONDUCTORS. IN SUCH A WAY TO BE ABLE TO MAKE A CHOICE OF THE INVERTER CONSIDERING THESE TWO INDICES. FINALLY TO CHECK WHAT IS PROPOSED, SIMULATION RESULTS ARE SHOWN.

IN PREVIOUS WORK, IT WAS PROPOSED TO USE MULTILEVEL CURRENT SOURCE CONVERTERS TO INCREASE THE CURRENT CAPACITY AS WELL AS IMPROVE THE HARMONIC PROFILE OF MEDIUM VOLTAGE AND HIGH CURRENT DRIVES. RECENT PUBLICATIONS SUGGEST THAT BOTH (A) ITS INTRINSIC BOOSTER CHARACTERISTICS AND (B) ITS EASY WAY TO HANDLE INDEPENDENT DC SOURCES OPERATING IN PARALLEL MAKE THIS TOPOLOGY AN ATTRACTIVE ALTERNATIVE FOR THE DIRECT CONNECTION OF PHOTOVOLTAIC PLANTS TO THE GRID. FURTHERMORE, STAGGERED OPTIMIZED PATTERNS WERE PROPOSED TOGETHER TO MODULAR TOPOLOGIES REGARDING THE IMPROVEMENT ON HARMONIC PROFILE OF INJECTED CURRENTS TO THE GRIDS. ONE OF THESE TECHNIQUES ARE THE STAGGERED SELECTIVE HARMONIC ELIMINATION. AN ALTERNATIVE IS THE STRAIGHTFORWARD OPTIMIZATION FOR REDUCE THE ERROR AMONG A TIME-BASED REFERENCE AND THE MODULATED CURRENT PATTERN. THIS WORK PRESENTS A COMPARISON BETWEEN THREE OPTIMIZED PATTERNS FOR THE OPERATION OF STAGGERED PATTERNS IN CURRENT SOURCE CONVERTERS, FOR BOTH SYMMETRIC AND ASYMMETRIC CASES. THEORETICAL RESULTS THAT ARE VALIDATED BY SIMULATION ARE PRESENTED.

IN HARD ROCK MINE OPERATIONS, THE GRAVITATIONAL SEGREGATION OF ORE PARTICLES WITHIN A STOCKPILE CREATES A HIGH VARIATION OF PARTICLE SIZE. THIS ISSUE HAMPERS PRODUCTIVITY IN THE COMMINUTION PROCESS AND HAS A DIRECT EFFECT ON THE DAILY OUTPUT OF PRODUCED MINERALS FROM THE MINE. DOZER OPERATION CAN BE FACILITATED TO MIX THE STOCKPILE MATERIALS FOR MAINTAINING A MORE HOMOGENEOUS PARTICLE SIZE DISTRIBUTION, HOWEVER THIS CAN LEAD TO POTENTIALLY HAZARDOUS SITUATIONS FOR THE MACHINE AND OPERATOR DUE TO THE DYNAMIC NATURE OF THE STOCKPILE. THE USE OF AUTONOMOUS BULLDOZERS IS A NEW TREND FOR MINE EQUIPMENT OPERATION, IMPROVING THE SAFETY OF DOZER OPERATORS WORKING IN THE STOCKPILE BY REMOVING THEM FROM THE MACHINE ALTOGETHER. THIS PAPER DESCRIBES PATH-PLANNING STRATEGY FOR AUTONOMOUS DOZERS TO OPERATE OVER A STOCKPILE WITHIN A PREDEFINED SAFE REGION. FOR THIS PURPOSE, A STOCKPILE MODEL IS DEVELOPED, WHERE LEVEL AND PARTICLE SIZE PROPERTIES ARE USED TO DESCRIBE THE STOCKPILE IN TERMS OF SECTORS. THIS INFORMATION IS THEN USED TO COMMAND THE OPERATION OF AN AUTONOMOUS DOZER OVER THE STOCKPILE BASED ON CURRENT SAG MILL FEED STATE. SIMULATION RESULTS PREDICT ACCEPTABLE BEHAVIOR, PROVIDED THAT SENSOR INFORMATION PROVIDES ENOUGH ACCURACY TO SPECIFY SAFETY AND PERFORMANCE CONSTRAINS.

IN THIS WORK, A COMPARATIVE ANALYSIS OF THE PERFORMANCE AND EFFICIENCY OF THE FCS-MPC AND MODULATION FBQ APPLIED TO AN AFE ACTIVE FRONT RECTIFIER IS CARRIED OUT. THE ABOVE COMPARES QUALITY INDICATORS OF FORM IN THE INPUT CURRENT OF AN AFE, THD, AND WTHD RECTIFIER. FOR EFFICIENCY, THE CONDUCTION AND COMMUTATION LOSSES IN THE SWITCHES WILL BE ESTIMATED TO OBTAIN A SELECTION CRITERION BETWEEN THESE TWO CONTROL METHODS, WHICH WILL BE BASED ON THE EFFICIENCY OF THE CONVERTER AND THE PERFORMANCE OF THE INPUT CURRENT LOOP. THE SEMICONDUCTORS LOSSES ARE CALCULATED BY LINEAR MATHEMATICAL APPROXIMATIONS, WHICH DEPEND ON THE OPERATION POINT OF THE AFE RECTIFIER AND THE SWITCH PARAMETERS, WHICH ARE OBTAINED FROM THE DATASHEET PROVIDED BY THE SWITCH MANUFACTURER, WHICH FOR THIS WORK, IGBT IKW25T120 WAS SELECTED. FINALLY, FOR THE PERFORMANCE ANALYSIS, SATISFACTORY SIMULATION RESULTS WERE OBTAINED.

NOWADAYS, STATIC POWER CONVERTERS HAVE A TRANSCENDENTAL ROLE AT AN INDUSTRIAL LEVEL. THE TWO-LEVEL CONVERTER IS STILL THE MOST USED, SUCH AS IN THE CASE OF USE IN AC ELECTRICAL MACHINE DRIVES OR THE INCLUSION OF RENEWABLE ENERGIES IN ELECTRICAL SYSTEMS. HOWEVER, DUE TO ITS ADMIRABLE ADVANTAGES, THE MULTILEVEL CONVERTER IS A VALID ALTERNATIVE FOR HIGHER QUALITY AND EFFICIENCY BENEFITS. IN PARTICULAR, ONE OF THE MOST STUDIED TOPOLOGIES IS THE CASCADED H-BRIDGE, WHICH CAN BE CLASSIFIED ACCORDING TO ITS DC VOLTAGE RATIOS AS SYMMETRICAL AND ASYMMETRICAL. THE LATTER MAKES IT POSSIBLE TO OBTAIN A HIGH-QUALITY OUTPUT VOLTAGE WAVEFORM USING FEWER INVERTERS PER PHASE. HOWEVER, THIS HAS DRAWBACKS SUCH AS: (I) REGENERATION DUE TO THE MODULATION TECHNIQUE, (II) ASYMMETRIC POWER DISTRIBUTION AMONG THE INVERTERS, AND (III) LOSS OF MODULARITY. IN THIS WORK, IT IS PROPOSED TO DESIGN A MODULATION TECHNIQUE FOR THE GENERATION OF A STEPPED PHASE VOLTAGE BASED ON THE SUM OF MODIFIED SQUARE WAVES GENERATED BY H-BRIDGE INVERTERS IN CASCADE WITH ASYMMETRIC DC VOLTAGE RATIO IN ORDER TO OBTAIN A DISTRIBUTION OF SYMMETRICAL ACTIVE POWER BETWEEN THE CELLS AND A MINIMUM THD OF THE OUTPUT PHASE VOLTAGE. FOR THE ABOVE, THE MINIMIZATION OF THE THD OF THE OUTPUT PHASE VOLTAGE IS PERFORMED. AS A RESULT, THE DC VOLTAGES AND FIRING ANGLES ARE OBTAINED FOR EACH MODIFIED SQUARE WAVEFORM. THUS, FOR SIX CELLS PER PHASE WITH M=1.0, 6.976% OF THD IS OBTAINED, AND AN EFFICIENCY OF 95.32%.

HIS PAPER PROPOSES A TOOL FOR THE EVALUATION OF ALGORITHMS FOR GRID SYNCHRONIZATION USING THE DELFINO LAUNCHPAD TMS320F28379D PLATFORM, WITH THE OBJECTIVE OF SUPPORTING DEVELOPERS AND RESEARCHERS IN THE VALIDATION BEFORE THEIR TEST IN GRID-CONNECTED EQUIPMENT. THE PROPOSAL USES THE DIGITAL TO ANALOG OUTPUTS AVAILABLE IN THE LAUNCHPAD TO EMULATE THE GRID VOLTAGE, PROVIDING VARIATIONS IN AMPLITUDE, FREQUENCY, AND PHASE AND AT THE SAME TIME, PROVIDING RELEVANT SIGNALS TO EVALUATE THE PERFORMANCE OF THE TESTED ALGORITHM IN A SCOPE. THE WORK PRESENTS (I) A GLOBAL CLASSIFICATION OF SYNCHRONIZATION TECHNIQUES AND EVALUATION SCENARIOS, (II) THE TOOL CHARACTERISTICS AND ITS IMPLEMENTATION METHODOLOGY, (III) A STUDY CASE AND ITS RESULTS WHERE TWO SYNCHRONIZATION TECHNIQUES ARE IMPLEMENTED IN AN OPEN-SOURCE DEVICE, AND (IV) FINAL DISCUSSIONS OF THE TOOL AND THE RESULT. © 2023 IEEE.

FEEDBACK QUANTIZER (FBQ) IS A CLOSED-LOOP MODULATION SCHEME WITH LOW HARMONIC CONTENT AT LOW FREQUENCY AND GOOD TRACKING OF THE VOLTAGE REFERENCE AT FUNDAMENTAL FREQUENCY. A GOOD MODULATION SCHEME TO BE APPLIED IN TRANSFORMER DEPENDENT SYSTEMS THAT ARE NOT SATURATED BY THE LOW FREQUENCY HARMONIC COMPONENTS. THIS PAPER PRESENTS AN ALTERNATIVE FOR THE APPLICATION OF FBQ USING SPACE VECTOR MODULATION, WITH THE OBJECTIVE OF OBTAINING A HIGHER ACCURACY IN TRACKING THE REFERENCE AND IMPROVE THE HARMONIC CONTENT OF THIS TECHNIQUE AT LOW SAMPLING TIMES. THE SIMULATED RESULTS SHOW THE FULFILLMENT OF THE OBJECTIVES SATISFACTORILY.

IN THIS PAPER, WE DESIGN AND EVALUATE A CONTROL SYSTEM WHICH, BY USING AS INPUT RSSI MEASURES, ALLOWS ANTICIPATORY MOVEMENTS OF ROBOTIC ARMS DECREASING IDLE TIMES AT THE CIMUBB LABORATORY. CLASSICAL LOG-NORMAL MODEL, WHICH RELATES THE STRENGTH OF A SIGNAL RECEIVED BY A NODE WITH THE DISTANCE AT WHICH THE SENDER OF THE SIGNAL IS, WAS ADOPTED. THE HIDDEN STATE OF THE SYSTEM IS DETERMINED BY THE EXTENDED KALMAN FILTER WHICH ALLOWS US TO ESTIMATE THE DISTANCE AND THE SPEED OF PALLETS MOVING OVER A CLOSED-LOOP CONVEYOR BELT. FROM THESE ESTIMATES, REMAINING TIME IN WHICH THE PALLET WILL GET TO A STOPPING POINT NEAR THE ROBOT IS DETERMINED. THIS INFORMATION IS FINALLY PROCESSED BY A CONTROLLER TO DETERMINE THE INSTANT AT WHICH THE ROBOT MUST OPERATE AND HANDLE THE PALLET. BOTH, A PROPORTIONAL-INTEGRAL AND A FUZZY CONTROLLER, WERE IMPLEMENTED AND EVALUATED. RESULTS SHOW THE FEASIBILITY OF USING WIRELESS SIGNALS TO ACCOMPLISH THE DESCRIBED GOAL, WITH SOME PRACTICAL RESTRICTIONS.

THIS PAPER PRESENTS A NOVEL APPROACH TO IMPLEMENT A MODULAR MULTILEVEL CONVERTER BASED ON ASYMMETRIC MODULES. THE PRESENTED ASYMMETRIC MODULAR MULTILEVEL CONVERTER IS ABLE TO GENERATE UP TO 27 LEVEL WITH 3 MODULES PER ARM THANKS TO THE RATIO 9:3:1 AMONG THE POWER CELLS. THE BALANCE CONTROL OF THE CAPACITORS OF THE TOPOLOGY IS MADE USING THE REDUNDANT STATES OF THE TOPOLOGY. THE FEASIBILITY OF THE PROPOSAL IS VALIDATED WITH COMPUTATIONAL SIMULATIONS IN THE TIME AND FREQUENCY DOMAINS OF A SINGLE PHASE CONVERTER.

FOR MEDIUM VOLTAGE APPLICATIONS, MULTILEVEL INVERTERS ARE USED. ONE OF ITS CLASSIC TOPOLOGIES IS THE CASCADED H-BRIDGE, WHICH REQUIRES ISOLATED DC VOLTAGES TO WORK. DEPENDING ON THE DC VOLTAGE RATIO USED IN THE CASCADED H-BRIDGE CAN BE CLASSIFIED INTO SYMMETRIC AND ASYMMETRIC. IN COMPARISON BETWEEN SYMMETRIC AND ASYMMETRIC INVERTERS, THE LATTER CAN GENERATE AN AC OUTPUT VOLTAGE WITH MORE OUTPUT VOLTAGE LEVELS. DC VOLTAGE RATIO MOST DOCUMENTED ARE BINARY AND TRINARY. THE LAST CAN GENERATE AN AC VOLTAGE OF 3N = 27 LEVELS IS OBTAINED, USING N = 3 INVERTERS IN CASCADE AND NLM MODULATION, WHICH GENERATES A FLOW POWER OF THE LOAD TO THE INVERTERS (REGENERATION). THIS WORK ANALYZES THE SEMICONDUCTOR LOSSES (SWITCHING AND CONDUCTION) AND THE THD OF THE AC OUTPUT VOLTAGE IN FUNCTION OF INDEX MODULATION, CONSIDERING A NON-REGENERATIVE MODULATION TECHNIQUE FOR A 27-LEVEL SINGLE-PHASE ASYMMETRIC INVERTER. TO CONFIRM THE THEORETICAL ANALYZES, SIMULATION AND EXPERIMENTAL RESULTS ARE SHOWN.

MULTILEVEL CONVERTERS ARE WIDELY USED IN MEDIUM VOLTAGE APPLICATIONS. ONE OF THE MOST POPULAR TOPOLOGIES IN THIS FIELD IS THE 18 PULSES DIODE RECTIFIER, WHICH USES A MUITIPUISE TRANSFORMER THAT REALIZES A CURRENT HARMONICS CANCELATION THAT ARE GENERATED BY THE THREE PHASE DIODE RECTIFIERS. IN THIS WORK AN EFFICIENCY COMPARISON OF THE AFOREMENTIONED TOPOLOGY AND A MULTI-CELL ACTIVE-FRONT-END (AFE) RECTIFIER OPERATING WITH FINITE CONTROL SET - MODEL PREDICTIVE CONTROL IS PERFORMED. THIS EFFICIENCY COMPARISON IS FOCUSED ON THE RECTIFIER LOSSES DIVIDED INTO TWO TYPES. THE FIRST ONE IS THE SEMICONDUCTORS SWITCHING AND CONDUCTION LOSSES. THE SECOND ONE EVALUATES THE TRANSFORMER LOSSES, WHICH ARE STUDIED UNDER TWO CRITERIA: COPPER LOSSES (STANDARD IEEE C57.10-1998) AND THE K - FACTOR (STANDARD IEEE / ANSI C57.110). THE RESULTS SHOW THAT THE DIODE BASED RECTIFIER TOPOLOGY HAS LOWER SEMICONDUCTORS LOSSES, WHILE THE TOPOLOGY BASED ON AFE RECTIFIERS HAS LOWER TRANSFORMERS LOSSES AND A LESS COMPLEX DESIGN. INDEED, A REDUCTION OF A 7.2% IN COPPER LOSSES IS ACHIEVED IN THE TRANSFORMER SECONDARY WITH RESPECT TO A MULTI-PULSE TRANSFORMER SECONDARY.

IN THE PRESENT WORK, THE PERFORMANCE OF THE ARDUINO DUE AND DELFINO LAUNCHPAD TMS320F28379D DEVELOPMENT BOARDS ARE EVALUATED AND COMPARED, TO BE A GUIDE FOR DEVELOPERS WHO MUST DECIDE TO MIGRATE THEIR APPLICATION, OR WHO MUST DECIDE BETWEEN BOTH TECHNOLOGIES AT THE BEGINNING OF THEIR PROJECT. WHEN CONSIDERING THE COMPATIBILITY OF THEIR ELECTRICAL LEVELS FOR THE CONNECTION OF PERIPHERALS AND DIFFERENCES IN COMPUTING CAPACITY. IN PARTICULAR, THE EXECUTION TIME OF MATHEMATICAL OPERATIONS AND INSTRUCTIONS OF COMMON USE IN THE ACQUISITION AND PROCESSING OF SIGNALS IS EVALUATED USING AVAILABLE FUNCTIONS IN C LANGUAGE. THE WORK CONSIDERS (I) THE EVALUATION OF THE CHARACTERISTICS OF HARDWARE AND DEVELOPMENT ENVIRONMENTS, (II) THE METHODOLOGY FOR THE EVALUATION OF EXECUTION TIMES,ALGORITHMS, AND CONFIGURATION CONSIDERATIONS, (III) CASE STUDY AND RESULTS, AND (IV) PERFORMANCE COMPARISON. THE RESULTS SHOW THAT BASIC MATHEMATICAL OPERATIONS WITH FLOATING-POINT ARE EXECUTED 16 TIMES FASTER WHEN MIGRATING FROM ARDUINO DUE TO DELFINO LAUNCHPAD.

THIS WORK STUDIED DIFFERENT DIGITAL EMBEDDED PLATFORMS WHICH CAN BE PROGRAMMED USING ARDUINO IDE SOFTWARE AND WHICH CAN BE USED FOR DIGITAL CONTROL AND DATA ACQUISITION APPLICATIONS. SPECIFICALLY THREE KIND OF ARDUINO BOARD (ARDUINO UNO, ARDUINO MEGA Y ARDUINO DUE) AND TWO ESP BASED BOARD (ESP8622 AND ESP32) ARE EVALUATED AND COMPARED. THE COMPARISON IS BASED ON THE EXECUTION TIME OF MATHEMATICAL OPERATIONS AND A FUNCTION REQUIRED FOR DATA ACQUISITION OR DIGITAL CONTROL AND INCLUDES (I) DIGITAL PORTS WRITING, (II) ANALOG SIGNAL ACQUISITION, (III) EXECUTION OF MATHEMATIC OPERATION IN INTEGER AND FLOAT FORMAT, AND (IV) THE EXECUTION OF THE DATA PROCESSING CODE. THE EXECUTION TIME IS MEASURED BY USING A METHODOLOGY WHICH IS SIMPLE TO IMPLEMENT FOR ANY OTHER DIGITAL DEVICE. BECAUSE OF EACH PLATFORM USES ITS OWN ARDUINO DUE LIBRARY TO GENERATE THE ASSEMBLY CODE FOR ITS OWN MICROCONTROLLER, THE INSTRUCTIONS ADOPTED FOR BOTH GENERATING THE ACTIONS TO MEASURE AND GENERATING THE TESTING SIGNALS ARE WRITTEN USING ARDUINO IDE COMMANDS AND USING INSTRUCTIONS THAT ANY ENTRY-LEVEL USER MAY ADOPT. IN CONCLUSION, FROM THE EXPERIMENTAL RESULTS IT IS OBSERVED THE HIGH DIFFERENCE IN THE EXECUTION TIME OF THE DIFFERENT PLATFORMS, ESPECIALLY BETWEEN ESPX BOARDS AND ARDUINO BOARDS.

THE CONTROL STRATEGIES THAT USE MODULATION TECHNIQUES HAVE GREAT ACCEPTANCE IN THE CURRENT CONTROL OF STATIC POWER CONVERTERS. INDEED, THEY OFFER A WIDE VARIETY OF ALTERNATIVES TO ADDRESS THE STEADY-STATE CHARACTERISTICS REQUIRED BY THE SYSTEM. NEVERTHELESS, ITS COMPUTATION AND MODULATION DELAY NEGATIVELY AFFECTS ITS DYNAMIC PERFORMANCE. IN ORDER TO IMPROVE THE TIME RESPONSE OF THE SYSTEM, THE MODULATOR IS AVOIDED AND THE STRATEGIES OF DIRECT CHOICE OF THE SWITCHING STATE HAVE BEEN PRESENTED. THEY CAN PROVIDE A VERY FAST DYNAMIC RESPONSE; HOWEVER, THE ABSENCE OF SWITCHING STATE SEQUENCES MAKES MORE COMPLEX THE TASK OF ESTABLISHING SPECIFIC SWITCHING FEATURES FOR IMPROVED STEADY-STATE PERFORMANCE. IN THIS WORK, A CONTROL SCHEME THAT SELECTS A SPECIFIC CONTROL STRATEGY ACCORDING TO THE OPERATING CONDITION OF THE SYSTEM IS PROPOSED. THIS ALLOWS USING MODULATORS TO SATISFY THE SWITCHING CHARACTERISTICS REQUIRED IN STEADY-STATE AND AVOIDS ITS USE WHEN A RAPID DYNAMIC RESPONSE IS REQUIRED. IN ADDITION, A SOFT TRANSITION METHOD BETWEEN THE CONTROL STRATEGIES IS PRESENTED TO PREVENT UNWANTED BEHAVIORS WHEN THESE ARE ALTERNATED. THE PROPOSED CONTROL SCHEME ALLOWS SIMPLIFYING THE DESIGN AND KEEPS THE MAIN ADVANTAGES OF EACH SELECTED STRATEGY. TO VALIDATE THE SCHEME, EXPERIMENTAL RESULTS ARE OBTAINED FOR A CONTROL STRUCTURE THAT ALTERNATES BETWEEN A FINITE SET MODEL PREDICTIVE CONTROL (DIRECT TYPE FOR RAPID DYNAMIC RESPONSE) AND A PROPORTIONAL INTEGRAL (PI) CONTROL WITH SINUSOIDAL PULSE WIDTH MODULATION (SPWM) (MODULATED TYPE FOR HIGH STEADY-STATE PERFORMANCE).

THIS WORK DEALS WITH A DISTRIBUTION STATIC SYNCHRONOUS COMPENSATOR (D-STATCOM) BASED ON A CURRENT-SOURCE CONVERTER FOR LOW AND MEDIUM VOLTAGE DISTRIBUTION SYSTEMS, SPECIFICALLY SMALL AND MEDIUM MANUFACTURES INDUSTRIES WHICH ARE FINED IF THE DISPLACEMENT POWER FACTOR IS BELOW GIVEN LIMITS. THE D-STATCOM IS ANALYZED USING ITS MATHEMATICAL MODEL, SHOWING THE STRONG RELATION OF THE D-STATCOM POWER LOSSES AND ITS DC CURRENT LEVEL. USING THE OPERATING REGION OF THE D-STATCOM, AN OPERATING SUB-REGION IS DEFINED SUCH THAT THE MINIMUM DC CURRENT IS USED FOR A REQUIRED REACTIVE COMPENSATION, WHICH LEADS TO REDUCING THE OPERATING LOSSES IN THE D-STATCOM. ALSO, SELECTIVE ELIMINATION HARMONIC IS USED TO MODULATE THE EQUIPMENT TO REDUCE THE SWITCHING FREQUENCY WHILE ENSURING A DESIRED CURRENT QUALITY IN THE D-STATCOM INPUT. AS A RESULT, A SIMPLE CONTROL STRATEGY IS PROPOSED THAT USES A FIXED MODULATION INDEX WHILE A PHASE CONTROL REGULATES THE DC CURRENT TO THE LOWEST VALUE REQUIRED FOR REACTIVE POWER COMPENSATION. MATHEMATICAL ANALYSIS JOINTLY WITH SIMULATED AND EXPERIMENTAL RESULTS CORROBORATES THE PROPOSAL, SHOWING THAT IT IS POSSIBLE TO ACHIEVE A SUITABLE COMPENSATION CAPABILITY FOR IMPROVING THE EFFICACY OF THE STATCOM.

A NOVEL CONTROL STRATEGY FOR SINGLE-PHASE CURRENT-SOURCE INVERTERS CONNECTED TO AN AC GRID IS PROPOSED IN THIS PAPER. THE CONTROL STRATEGY AIMS TO INJECT MAXIMUM POWER TO THE GRID UNDER TRANSIENT AND STEADY-STATE CONDITIONS BY THE TRACKING OF SINUSOIDAL REFERENCES. THIS PAPER PRESENTS THE MODELING AND THE DESIGN OF THE CONTROL STRATEGY BASED ON THE EXACT LINEARIZATION OF THE INVERTER MODEL. RESULTS ARE OBTAINED BY COMPUTATIONAL SIMULATION AND VALIDATED EXPERIMENTALLY. BY USING ERROR PERFORMANCE INDEXES IN THE ANALYSIS OF THE RESULTS, IT IS DEMONSTRATED THAT THE PROPOSED CONTROLLERS ACHIEVE CORRECT TRACKING OF THE SINUSOIDAL REFERENCE WHILE KEEPING A LOW SWITCHING FREQUENCY, WHICH HELPS TO MINIMIZE THE COMMUTATION LOSSES.

THIS WORK PROPOSES A MULTICELL TOPOLOGY BASED ON CURRENT-SOURCE CELLS IN ORDER TO INHERIT THE ADVANTAGES OF CURRENT-SOURCE TOPOLOGIES SUCH AS REDUCED LOAD DV/DT VOLTAGE AND NATURAL BIDIRECTIONAL POWER FLOW AND TO ADOPT A SIMILAR BEHAVIOR OF THE MULTICELL TOPOLOGY BASED ON A VOLTAGE SOURCE CONVERTER SUCH AS VOLTAGE CONTROLLED BEHAVIOR WHERE N C CELLS ARE CONNECTED IN SERIES TO FEED ONE LOAD PHASE. IN ORDER TO CHECK THE TECHNICAL FEASIBILITY AND PERFORMANCE OF THE PROPOSED TOPOLOGY, A MATHEMATICAL MODEL IS INTRODUCED AND STUDIED AND KEY DESIGN GUIDELINES OF PASSIVE COMPONENTS ARE DEFINED. THE ANALYSIS SHOWS THE POSSIBILITY OF USING COMPONENTS WITH A LOWER VOLTAGE RATING THAN THAT OF THE CLASSIC MULTILEVEL CURRENT SOURCE TOPOLOGIES AND ALLOWS THE USE OF LOW SWITCHING FREQUENCIES IN BOTH RECTIFIER AND INVERTER STAGES WHILE AT THE SAME TIME OBTAINING A HIGH-QUALITY WAVEFORM IN BOTH LOAD VOLTAGE AND CONVERTER INPUT CURRENTS. A CASE OF EXAMPLE IS USED TO CORROBORATE THE THEORETICAL ANALYSIS AND THE COMPONENT DESIGN METHODOLOGY, AS WELL AS THE PERFORMANCE OF THE TOPOLOGY USING A LOW-POWER PROTOTYPE.