Question

11.15 PWM bidirectional motor controller. Using the PWM principle in Figure 11.18 and the H-bridge in Figure 11.20, the speed of a DC motor can be controlled in both directions a Draw a schematic of the pulses and show how the speed can be controlled and how the direction of rotation can be changed using a single PWM generator. The PWM generator is available as a stand-alone unit Show how the bridge circuit can be modified to affect braking of the motor To brake the motor it is sufficient to short its connection either to ground o to the +V rail b. or FIGURE 11.18 Generation of a PWM signal. The sinusoidal signal's ampitude is represented a pulse widths 11.3 I Power Ampliiers 587 FIGURE 11.19 A load driven by a PWM cirouit. The tasd Comparatoe transistor serves as a switch and power is controlled by the average of the PAM signal Tming eput ignal FIGURE 11.20 Driving an H-bridge -V tom a PWM source Both irputs (A and Bare PWM signals to control the speed of the motor in both Metr drections Show transcrbed image tet

Answer 1

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