Скачать с ютуб Lecture 1: Basic Concept of DC Choppers(DC to DC Converters) : Principle of Operation & Applications в хорошем качестве

Lecture 1: Basic Concept of DC Choppers(DC to DC Converters) : Principle of Operation & Applications

Basic Concept of DC Choppers(DC to DC Converters) : Principle of Operation & Applications : Topics : Introduction to Choppers AC link Chopper and DC chopper Definition & Principle of operation of DC chopper General Features of DC choppers Functions of DC choppers Applications of DC choppers Types of DC choppers Chopper is a device which converts fixed DC voltage to variable DC voltage Systems that perform better with variable DC voltage source Subway car Trolley buses Battery operated vehicle Battery chargers The conversion of fixed DC voltage to variable DC voltage is done by : AC link Chopper DC Chopper AC Link Chopper : First DC is converted to AC by inverter ⇛ AC is stepped up/stepped down by Transformer ⇛ which is then converted back to DC by Diode rectifier DC Chopper : It is static device which converts fixed DC voltage to variable DC voltage directly in single stage. It is static device which converts fixed DC voltage to variable DC voltage directly in single stage. Principle of Chopper Operation : Power devices has ON state voltage drop of 0.5V to 2.5V across them. Power devices are represented by switch SW with arrow. SW is ON ⇒ Current flows in direction of arrow SW is OFF ⇒ C No current flows. Functions of DC choppers To convert DC input voltage to DC output voltage. To regulate DC output voltage against load and line variations. To reduce AC voltage ripple on DC output voltage below required level. To provide isolation between the input source and load. To protect the supply system and source from Electro magnetic interference. General Features of DC choppers DC choppers are designed using power BJT, POWER MOSFET,GTO or forced commutated thyristor as semiconductor switch. They can provide smooth acceleration control to motors DC choppers are highly efficient Fast dynamic response They can offer regenerative breaking of DC motor, resulting in energy saving. Applications of DC choppers Transport Systems Traction motor control in electric automobiles Trolley cars Marine hoists Forklift trucks Mine haulers Used in DC voltage regulators #DCChopper #DCtoDCConverter #PrincipleofOpertionofDCtoDCconverter #PrincipleofOpertionofDCChopper