Step-Down Chopper with Low Pass Filter
A step-down chopper is a power electronic device that lowers the voltage of a direct current power source . It utilizes semiconductor devices to control the energy transfer . When coupled with low pass filter , the chopper minimizes high frequency voltage ripples in the output . The low pass filter ,typically an inductor and capacitor network , attenuates high frequency components , ensuring smoother and stable DC output voltage . Step down choppers with low pass filters finds applications in various systems , including voltage regulators for sensitive electronic devices where constant and clean power supply is crucial for optimal performance. This converter is used if the objective is to produce an output that is purely DC . If the low pass filter is ideal , the output voltage is the average of the input voltage to the filter .
Case 1 : When the switch S is closed , diode D is reverse biased and supply voltage will charge the inductor .
V0 = Vs - VL
Case 2 : When the switch S is open , inductor L will starts discharging through the diode D and feed the load .
V0 = -VL
VL(on) = Vs – V0
I c(on) = IL – I0
VL(off) = -V0
I c(off) = IL – I0
Since the average voltage across the inductor is zero .
(Vs – V0) Ton + (-V0) (Toff) =0
V0 = Vs .[Ton/(Ton + Toff )]
V0 = Vs . [Ton/T]
V0 = δ .Vs
Where δ= Ton /T
RMS output voltage V 0rms =√ δ. Vs
Step Down Chopper
In power electronics, a chopper refers to a type of electronic switch that is used to control the flow of electrical power. It functions as a high-speed ON/OFF semiconductor switch that modulates the voltage or current in a circuit. A chopper is a static device that transforms a fixed DC input voltage into a variable DC output voltage. It acts as the DC counterpart(equivalent) of an AC transformer due to its similar behavior. These are also used in trolley cars, marine hoists, forklift trucks, and mine haulers. Future electric automobiles are likely to use choppers for their speed control and braking. The chopper system offers smooth control, high efficiency, fast response, and regeneration.
Table of Content
- What is Chopper?
- Classification of Chopper
- Construction and Components of Step-Down Chopper
- Step-Down Chopper with Low Pass Filter
- Advantages of Step Down Chopper
- Disadvantages of Step Down Chopper
- Applications of Step Down Chopper
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