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This last transformation greatly reduces system complexity by expressing the currents as dc quantities. Combining the rotor flux angle (θ) with currents obtained from the Park Transformation lets you obtain the actual motor field and torque. By allowing a comparison of reference torque and measured torque, the Park Transformation plays a major role in the control loop. After you obtain the desired torque and flux, an Inverse Park Transformation translates the reference torque and field currents (idref, iqref) back, first to the orthogonal stator-frame currents ( iα, iβ) and then to their respective three-phase instantaneous stator currents (ia, ib, and ic). All transformations are carried out by a DSP. The real-time execution of control and input commands is handled by a microprocessor.
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