A 73% increase in Speed and Power is available from most all small AC motors. The same for larger motors when purchased with a special winding. Simply use a 230V x 50Hz motor at 400V x 87Hz, when supplied by an Inverter Drive.
[pdf] When it comes to speed control, the common choice is a three-phase induction motor that controls speed by use of a general-purpose inverter. For many, this may be the natural choice because it allows you.
[pdf] The PWM duty cycle follows the sine function, in this case sin (2πf) or sin (2π*50). Since 50% (0.5) duty-cycle corresponds to 0V on the sinewave, the complete function would be [duty-cycle = 0.5 + 0.5*sin (2π*50)].
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