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Figure 3.1 shows a mosfet drive circuit for one phase of a unipolar stepper motor where the supply voltage Vs = 12 V; Phase resistance R = 70 R; Phase Inductance L = 60 mH:− (i) How long does it take to establish the rated current of 0.19 Amps in the motor coil once the mosfet switch is turned on? (ii) Explain with the aid of diagrams two methods which can be used to alleviate the L/R time constant limitation of the coil? Figure 3.1 Mosfet drive circuit for one phase of a unipolar stepper motor

Figure 3.1 shows a mosfet drive circuit for one phase of a unipolar stepper motor where the supply voltage Vs = 12 V; Phase resistance R = 70 R; Phase Inductance L = 60 mH:− (i) How long does it take to establish the rated current of 0.19 Amps in the motor coil once the mosfet switch is turned on? (ii) Explain with the aid of diagrams two methods which can be used to alleviate the L/R time constant limitation of the coil? Figure 3.1 Mosfet drive circuit for one phase of a unipolar stepper motor

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Figure 3.1 shows a mosfet drive circuit for one phase of a unipolar stepper motor where the supply voltage Vs= 12V; Phase resistance R=70R; Phase Inductance L = 60 m H : − (i) How long does it take to establish the rated current of 0.19Amps in the motor coil once the mosfet switch is turned on? (ii) Explain with the aid of diagrams two methods which can be used to alleviate the L/R time constant limitation of the coil? Figure 3.1 Mosfet drive circuit for one phase of a unipolar stepper motor

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