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Explore the operation of diodes in high voltage applications like HVDC systems. Learn about series and parallel configurations to handle high current effectively. Understand voltage sharing, resistances, and examples. Enhance your knowledge in power electronics.
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بسم الله الرحمن الرحيم The Islamic University of Gaza Faculty of Engineering Electrical Engineering Department POWER ELECTRONICS EELE 5450— Summer 2012 Instructor: Eng. Jalal Al Roumy Lecture 4
Chapter Two Series and Parallel operation In many applications, the power handling capability of a single power diode is not sufficient. (HVDC applications).
Chapter Two Series and Parallel operation Series and parallel combination of diodes are essentially for handling the high voltage and high current necessary in such applications. Steady-state and transient voltages must be equally shared when diodes are connected in series. When diodes are connected in parallel, each diode must share the total load current equally, both under transient and under steady state conditions.
Chapter Two Series operation of diodes Series-Connected Diodes
Chapter Two Series operation of diodes Series-Connected Diodes with Voltage Sharing
Chapter Two Series operation of diodes Is=Is1+IR1=Is2+IR2, IR1=VD1/R1, IR2=VD2/R2
Chapter Two Series operation of diodes More than two diodes
Chapter Two Series operation of diodes Series-Connected Diodes with Dynamic Voltage Sharing
Chapter Two • Example: • Find the diode voltages if R1 = R2 =R = 100 k • Find the voltage sharing resistances R1 and R2 for equal diode voltages
Chapter Two • Example: • Find the diode voltages if R1 = R2 =R = 100 k • Vd1=2750V • Vd2=2250V • Find the voltage sharing resistancesR1 and R2 for equal diode voltages • Let R1=100k • R2= 125K
Chapter Two Parallel-Connected Diodes End of Lecture