The Principles of Switching Power Conversion

in either of the cases above (energy or people), from the viewpoint of an observer, a stream will be seen entering, and a similar one exiting. But at an intermediate stage, the transference is accomplished by breaking up this stream into more manageable packets. 

Power supplies that use this principle are called switching power supplies or switching power converters.  

In a practical implementation, application conditions are considered to be the applied input voltage Yin (also called the Tine voltage ), the current being drawn from the output, 

However, the rate at which the output can be corrected by the power supply (under sudden changes in line and load) is also important — since no physical process is instantaneous either. So the property of any converter to provide quick regulation (correction) under external disturbances is referred to as its loop response. Clearly, the loop response is as before, a combination of its step-load response and its line transient response.  

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