Abstract
The PWM control technology is in the one widely applies in the control domain technology, its principle is using the impulse is equal, but the shape is interlinked the narrow pulse adds in has when the inertia link, the effect basically is interlinked. In the electric drive system, adjusts the armature voltage the direct-current velocity modulation applies the most widespread one velocity modulation method, besides obtains the adjustable DC voltage using the thyristor rectifier, but may also use the other electric power electronic component's controllable performance, uses the pulse-duration modulation technology, the constant DC voltage will modulate the polarity to variable directly, the size adjustable DC voltage, with realizes the direct current motor armature both sides voltage stepless regulation, the constitution cocurrent pulse width velocity modulation system, along with the electric power electronic device's rapidly expand, uses the gate to be possible to shut off transistor GTO, to control electric power transistor GTR, P-MOSFET, insulation grid transistor IGBT extremely) and so on some high efficiencies to control the component compositionThe transistor pulse adjusts the wide switching amplifier (Pulse Width Modulated), has developed gradually maturely, the use is getting more and more broad.
Key word Direct-current velocity modulation PWM control Closed-loop control