Why does PWM reduce voltage, current, or power?
If the space between the pulses is increased and the time the voltage is switched on is reduced then less average power is provided to the load in a given time period so more work is done. The voltage and current remains the same but the voltage and current flow for less time in a given period and less work is done.
How is an inductive load connected to a DC power supply?
Figure 1 shows an inductive load connected to a DC power supply. When the power supply is turned on, current flows through the coil and a magnetic field builds up around the inductor. That magnetic field is a source of potential energy.
How is motor current measured in a PWM power amplifier?
Almost any modern motor controller (like the maxon product lines EPOS, ESCON, MAXPOS) use a so-called chopped PWM power amplifier to drive the motor, i.e. to provide the required motor current depending on the operating mode, the controller state, and working point. maxon controllers measure the motor current directly in the power amplifier.
How does PWM fake an analog like result?
PWM “fakes” an analog-like result by applying power in pulses, or short bursts of regulated voltage. Figure 1: An example of a PWM signal shown at several duty cycles and a high voltage level of 5 volts. The red line is the average voltage that the driven device (e.g., a motor) is experiencing.
How does the pulse width change in a PWM?
In this case, the pulse width (and corresponding duty cycle) change so that the average voltage looks more like an analog output that is not in a steady state such as shown in Figure 1. (Source: Zureks – Own work, CC BY-SA 3.0, )
What does it mean when PWM is on and off?
PWM is digital, which means that it has two states: on and off (which correspond to 1 and 0 in the binary context, which will become more relevant to you if using microcontrollers). The longer each pulse is on, the brighter the LED will be. Due to the fact that the interval between pulses is so brief, the LED doesn’t actually turn off.