Electric power is essential in daily life and its consumption is continuously increasing. Consequently, the need to efficiently manage electric power will become fundamental. About half of worldwide energy consumption is used by systems based on electric motors. In these systems, it is possible to achieve the conversion of electrical energy with high levels of flexibility and efficiency by using appropriate technique called "inverter" technology. This method is based on the use of high-voltage power switches, arranged in "inverter-leg" configuration, driven by Pulse Width Modulation (PWM) control. Gate drivers are responsible for providing the appropriate voltage levels to drive these power switches. Gate drivers represent the interface between the low-voltage domain of the microcontroller (used for generating the gate driver’s PWM input signals) and the high-voltage domain of the power switches. In these PWM systems, fault conditions may happen even during normal operation, affecting the motor phase functionality. Therefore, it is essential to include in the gate driver circuits that can detect these fault conditions in order to prevent damages to the power switches. The purpose of this thesis is the design of a circuit for the protection of power switches against motor phase short circuits, on a Silicon On Insulator (SOI) process made available by Infineon Technologies. To this end, a new solution has been implemented and compared to another approach based on a well-known technique, called “Bit transfer”. Both solutions are simulated and compared in terms of performance and silicon area estimation. The results show that the new proposed solution adds the possibility to detect if the motor phase is shorted to the system voltage supply, while the “Bit transfer” approach allows only detection of short to ground condition. Moreover, the new solution leads to a significant reduction of area, compared to the “Bit transfer” one. Chapters 1 and 2, introduce to motor control systems, with particular focus on the working principles of the gate driver and the types of short-circuit event that can occur during normal operation. Chapter 3 describes the designed circuits and the comparison between the new approach and the “Bit transfer” solution. Chapter 4 shows the simulations and area estimation for both solutions. Finally, the conclusions are drawn. This work was developed in collaboration with Infineon Technologies Pavia.
L'energia elettrica è essenziale nella vita quotidiana ed il suo consumo è in continuo aumento. Di conseguenza, la necessità di gestirla in modo efficiente diventerà fondamentale. Circa la metà dell’ energia elettrica consumata nel mondo è utilizzata da sistemi basati su motori elettrici. In questi sistemi, è possibile ottenere un alto livello di rendimento utilizzando la cosiddetta tecnologia "inverter". Questo metodo si basa sull'utilizzo di interruttori di potenza ad alta tensione, disposti in configurazione “inverter-leg” e guidati da segnali ad impulso a larghezza variabile (PWM, Pulse Width Modulation). I gate driver sono i dispositivi utilizzati per pilotare questi interruttori di potenza e rappresentano l'interfaccia tra il dominio a bassa tensione del microcontrollore (utilizzato per generare i segnali PWM) e il dominio ad alta tensione degli interruttori di potenza. Durante il normale funzionamento di questi sistemi, possono verificarsi guasti che vanno a ripercuotersi sulla fase motore. È pertanto essenziale includere, all’interno del gate driver, dei circuiti in grado di rilevare queste condizioni di guasto, al fine di evitare danni agli interruttori di potenza. Lo scopo di questa tesi è la progettazione di un circuito per la protezione degli interruttori di potenza contro i cortocircuiti della fase motore, su un processo tecnologico Silicon On Insulator (SOI) reso disponibile da Infineon Technologies. A tal fine, è stata implementata una nuova soluzione e confrontata con un altro approccio basato su una tecnica nota, chiamata 'Bit transfer'. Entrambe le soluzioni sono state simulate e confrontate in termini di funzionalità e stima dell'area occupata su silicio. I risultati mostrano che la nuova soluzione proposta aggiunge la possibilità di rilevare se la fase del motore è in cortocircuito con la tensione di alimentazione del sistema, mentre l'approccio “Bit transfer” consente solo di rilevare la condizione di cortocircuito a terra. Inoltre, la nuova soluzione porta a una riduzione significativa dell'area, rispetto a quella del "Bit transfer". I capitoli 1 e 2 introducono i sistemi di controllo del motore, con particolare attenzione ai principi di funzionamento del gate driver e ai tipi di eventi di cortocircuito che possono verificarsi durante il normale funzionamento. Il Capitolo 3 descrive i circuiti progettati ed il confronto tra il nuovo approccio e la soluzione “Bit transfer”. Il Capitolo 4 mostra le simulazioni e la stima dell'area per entrambe le soluzioni. Infine, vengono tratte le conclusioni. Questo lavoro è stato sviluppato in collaborazione con Infineon Technologies Pavia.
Design di un circuito di identificazione dei fault per la protezione dei power switches nei sistemi di controllo motore PWM
BRUNOLDI, LUCA
2022/2023
Abstract
Electric power is essential in daily life and its consumption is continuously increasing. Consequently, the need to efficiently manage electric power will become fundamental. About half of worldwide energy consumption is used by systems based on electric motors. In these systems, it is possible to achieve the conversion of electrical energy with high levels of flexibility and efficiency by using appropriate technique called "inverter" technology. This method is based on the use of high-voltage power switches, arranged in "inverter-leg" configuration, driven by Pulse Width Modulation (PWM) control. Gate drivers are responsible for providing the appropriate voltage levels to drive these power switches. Gate drivers represent the interface between the low-voltage domain of the microcontroller (used for generating the gate driver’s PWM input signals) and the high-voltage domain of the power switches. In these PWM systems, fault conditions may happen even during normal operation, affecting the motor phase functionality. Therefore, it is essential to include in the gate driver circuits that can detect these fault conditions in order to prevent damages to the power switches. The purpose of this thesis is the design of a circuit for the protection of power switches against motor phase short circuits, on a Silicon On Insulator (SOI) process made available by Infineon Technologies. To this end, a new solution has been implemented and compared to another approach based on a well-known technique, called “Bit transfer”. Both solutions are simulated and compared in terms of performance and silicon area estimation. The results show that the new proposed solution adds the possibility to detect if the motor phase is shorted to the system voltage supply, while the “Bit transfer” approach allows only detection of short to ground condition. Moreover, the new solution leads to a significant reduction of area, compared to the “Bit transfer” one. Chapters 1 and 2, introduce to motor control systems, with particular focus on the working principles of the gate driver and the types of short-circuit event that can occur during normal operation. Chapter 3 describes the designed circuits and the comparison between the new approach and the “Bit transfer” solution. Chapter 4 shows the simulations and area estimation for both solutions. Finally, the conclusions are drawn. This work was developed in collaboration with Infineon Technologies Pavia.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/17184