UNIVERSITA DI CATANIA

UNIVERSITA DI CATANIA DIEES Department of Electrical Electronic and Systems Engineering XXI Brain Storming Day Unict Catania 29 Ottobre 2010 Ph.D. student - XXV ciclo Tutor Prof. Angelo Raciti

Subjects of Research Power Switching Converters (Low and Medium Power). a. LED Lamps or Solid State Lighting (SSL) b. Power Converters for Power Module IGBTs and Short Circuit Failure Mode (SCFM)

LED Lamps (SSL) The Research Activity is part of a European project, CSSL Project (Consumerizing Solid State Lighting). 27 Partners, such us: (Philips lighting, Research; TNO; M2i; Boschman BV; Wittenburg; STMicroelectronics; Università di Catania - DIEES; Archimede; Cambridge University, Nat. Centre of Microelectronics, Leitat, Czech Technical University and other ). LED Lamps or SSL (Solid State Lighting)

Work Plane The workpackages and their objective are: WP 1 Specification and Architecture WP 2 LED Device WP 3 Electronics and Control WP 4 Reliability, Thermal and Safety WP 5 Prototype and Verification WP 6 Project and Management, Dissemination and Exploration

Work Plane WP 3 Electronics and Control WP3 will design, develop, validate and prototype a new generation of integrated electronic driver for LED lighting including the dimming control. It will focus on features that can be classified into three levels: Low End (Basic features, very low cost), Mid End (general purpose features) and High End (Advanced features). For instance, features such as tuneable white colour, failure diagnosis and detection, Power factor control, switch and dimming control through wired or wireless protocols, etc. WP 5 Prototype and Verification The objectives of WP5 are : integrate development and innovation achievements and deliver physical demonstrators on both component and system level; evaluate retrofit prototypes, comparable retrofit products and the integrated system through field assessments; promoting and developing market for the SSL retrofit products by working with utility partners.

Solid State Lighting Outline I. Study of the bright greatness and transmission of the heat. II. Comparison between the more important LED Lamp manufactures. III. Study and Analysis of the high light LED technology devices. IV. Analysis of the Power Converter Architectures for Module LEDs driving. V. Realization by a LED Lamp prototype. VI. Thermal characterization in order to understanding the temperature limit of the prototype. VII. Electrical Characterization, Evaluation of the electrical stress in short circuit condition, over voltage and voltage decrease, LED failure, and other.

Light and Electrical System Feature Light Feature Value System flux 806 lm System efficacy 67 lm/w CCT 2700 CRI >85 Dimmable 10%-100% Lifetime >25000 h Maximum input power < 12 W Operating temperature -20 C to 45 C Electrical Feature Input Voltage Dimming compatibility Value Dimming levels 10% - 100% Low level start Flickering 230V +/- 10% AC 50 Hz Leading and trailing edge Lamp start at lowest dimmer setting No flicker for recommended dimmer list Driver efficiency > 85% light on within 0.5 s. At Starting nominal power: 30% flux after 0.1s, 70% after 1.0s under nominal operation Output power 11 W Early failures < 1% failures after 1000h

Dimmer Compatibility The dimmer is a device that to allows reduce the power consumption by the load (LEDs) and it can be controlled in remote. Furthermore, it s causes harmonic distortion due to cut the shape of the grid waveform and alike increases in frequency components. Digital Dimming: When the device is supplied from a dimmer, the LED current is decreased by a PWM. The duty cycle of the PWM is set according to the AC mains RMS value. Bleeder Circuit. It allow the device to operate on low AC RMS input Voltage, because this circuit pull the minimum current that keep ON TRIAC in the dimmer

Architecture Topology Feature Requirements 1. High Efficiency 2. Low Cost 3. Low Output 4. Voltage 5. PFC > 0.7 Characteristics Power Converter 1. Not isolated Power Converter 2. Buck Converter 3. Active PFC

Experimental Analysis on Switch Driving in Buck Converter Options: 1. Power MOSFET N-Channel 2. Power MOSFET P- Channel COMPARISON First. Topology: Shift level (N Ch) Second Topology: Current Mirror (P-Ch) V outdc Bleeder Power Switches Bleeder Power Switches

Losses in Power MOSFET and Global Efficiency V inac [V] V indc [V] D [%] P ON [W] P OFF [W] P COND [W] P TOT [W] P load [W] P IN [W] η [%] 15 21,2 94,3 28 10-3 5,8 10-3 0,292 0,326 4,1 5,9 69 150 212 9,4 0,389 0,148 0,110 0,656 7,27 10,6 68 220 311 6,3 1,280 0,400 59 10-3 1,739 7,27 10,8 67 V outdc Power Switches

Losses in Power MOSFET and Global Efficiency V inac [V] V indc [V] D [%] P ON [W] P OFF [W] P COND [W] P TOT [W] I G [A] I D [A] 220 311,13 6,5 0,275 1,15 98 10-3 1,52 19 10-3 380 10-3 Power Loss on Current Mirror: P losses ~500 mw Power Switches

INTERNSHIP University of Catania, DIEES ARIEL, Catania, Italy ABB Corporate Research, Västerås, Sweden Internship in ABB AB Corporate Research, Västerås (SW), from. 1-09-2010 to. 28-02-2011 Tutor: Prof. Angelo Raciti Ing. Filippo Chimento

Operating Field of Research High Power System > 1 MW + V linea 400 V 4 kv - V blocco ~ 4.5 kv I N ~ 1 ka IGCT IGBT

Operating Field of Research GDU Turn ON Process Turn OFF Process Monitoring functions Protective functions Logic Control FPGA Power Supply DC-DC Converter GDU (Gate Drive Unit) Protection Circuits Interfaces I/O

Outline 1. Auxiliary Supply System in failure condition 2. Power Supply for IGBT and IGCT Gate Driving (Scaling components System from 5 W to 100 W) 3. SCFM (Short Circuit Failure Mode) operation of Power Module IGBTs Typical HVDC-FACTS Topology 3. 1. 2.

Power Converters for Power Module IGBTs 1. Auxiliary Supply System in failure condition a. Optical Power Supply b. Systems fed by external circuits

Power Converters for Power Module IGBTs 1. Auxiliary Supply System in failure condition a. Optical Power Supply Primary DC/DC 3-5 V Secondary DC/DC 15 V Logic DC/DC 1.2 1.8 V Detector Optical input power supervision Driver Logic

Power Converters for Power Module IGBTs 1. Auxiliary Supply System in failure condition b. Systems fed by external circuits G.U. G.U. G.U.

Power Converters for Power Module IGBTs 1. Auxiliary Supply System in failure condition b. Systems fed by external circuits G.U. G.U. G.U. G.U.

Power Converters for Power Module IGBTs 2. Power Supply for IGBT and IGCT Gate Driving (Scaling components System from 5 W to 100 W) The GDU needs a external power supply that gets energy by the external circuit V line 400 V 4 kv

Power Converters for Power Module IGBTs 1. The devices size choice (Active and Passive) In order to obtain 300 V in output of the DC-DC 1, the Buck Converter has been used as DC-DC Power Converter topology. Topics Discussed 2.Voltage Sharing in Series Connection Devices 3.Series Connection Devices Driving a. MOSFET 3X 1500V/8A b. Diode 4 X 1200V/5A c. Inductor L = 53 mh d. Capacitor C =... Passive solution for voltage sharing balance

Short Circuit Failure Mode (SCFM) 3. SCFM of Power Module IGBTs 1. In HVDC application, to prevent shut down of the system due to the defect arising in a IGBT Module, redundant modules are included in the system, such that the surviving modules share the voltage and the failed module is still able to carry the load current. 2. This short circuit failure mode has an important consequence on the Module design. A single failed chip and its contact system must conduct the whole load current. To reduce the resistance of the failure path through the chip, a metal platelet is used in contact with the silicon chip. 3. When the chip fails, it dissipates, for a very short duration, a sufficiently high energy to melt the platelet and forms a stable alloy with silicon. Metals like silver and aluminum are preferred as they form low melting eutectic alloys with silicon.

Publications 1. Convertitori di potenza nel campo del lighting: soluzioni innovative per l applicazione alle lampade a catodo freddo, F. Chimento, S. Musumeci, A. Raciti, S. Tomarchio, R. Scollo, Proceedings of Congresso Nazionale AEIT, AEIT'06, Capri (Italy), September, 16th-20th 2006. 2. Optimized Design of Power Semiconductor Devices for DC-AC Royer Converter Topology in Case of CCFL Lighting Applications, F. Chimento, S. Musumeci, A. Raciti, S. Tomarchio, R. Scollo, Proceedings of the 12th International Power Electronics and Motion Control Conference, EPE-PEMC 2006, August 30th - September 1st, 2006, Portoroz, Slovenia. 3. Dispositivi di potenza innovativi in convertitori DC-DC per la produzione di energia da campi fotovoltaici, A. Raciti, S. Musumeci, S. Tomarchio, R. Scollo, S. Buonomo, L. Abbatelli, AEIT 2009, Sostenibilità energetica: Tecnologie e Infrastrutture - La ricerca incontra l'industria, Catania (Italy), September, 27th- 29th 2009. Submitted: 1) Paper for publication on EPE Journal, Experimental Investigation of a Monolithic Cascode device in a Forward Converter for Industrial Application. 2) A High Input Voltage Power Supply for Gate Driving Application Based on Series Connection of Power Switches 3) Parasitic Evaluation in IGBT Module with Physics Based and Behavioural Model 4) Influence of the Temperature on the Parameters of Punch Through IGBTs in Parallel Connection