Week 4 Session 5
Power Converters:
A power converter is an electrical or electro-mechanical device for converting electrical energy. A power converter can convert alternating current (AC) into direct current (DC) and vice versa; change the voltage or frequency of the current or do some combination of these.
Types of Power Converters:
1. AC-AC converters
2.DC-DC converters
3.AC-DC converters
4.DC-AC converters
1. AC-AC converters :
Normally these types of converters are called Cyclo-Converters which is not used in electric vehicles.
2.DC-DC converters:
converts an unregulated DC to regulated DC
1. Non-Isolated converters:Buck, Boost , Buck-Boost
2. Isolated converters: Flyback,Forward , Half-Bridge,Full-Bridge
3.Resonant converters: Different family of DC-DC converters used for high power conversion
Note:
Isolated converters means the input and output sides are isolated whereas in case of non-isolated the input and output sides are not isolated .
Applications Of DC-DC converters :
1.car air-conditioning system
2.Music System
3.Head Lights
4.Dimmer
5.High Voltage (HV) - Low Voltage (LV) Battery Link
6.Accumulating different energy sources to give the desired output
3. DC-AC converters:
Commonly called as inverters , can control both magnitude and frequency of output AC voltage
Widely seen in control of AC motors
4. AC -DC Converters:
Commonly called as rectifiers , widely seen in battery chargers
Rectifiers with power factor correction are popular in industry
The type of converters used for horn which requires less than 10 volt is DC - DC converter in which buck converter is used to stepdown the voltaged from high level voltage to less than 10 volt which is used to produce horn.
Applications of power converters in electric vehicles :
The initial step is Battery charging either via adapter which has an inbuild AC - DC converter wheras in plug-in where there will be a on-board charger which is used to convert AC - DC , The AC - DC converter commonly known as rectifier which is used for battery charging
Next , DC-DC converter converts DC from source to destination side according to its requirement like it need higer level voltage or lower level voltage used in various auxillary loads like headligts , automatic window etc., in electric vehicles
Then , DC - AC converter also called as inverter is used to convert DC to AC which is used to fed power to AC motor from battery and we can also control it via this types of converters .