Field Oriented Control (FOC) is a control technique used in electric motors to achieve high performance in terms of efficiency, torque response, and speed control. It involves controlling the two components of the motor current, the torque-producing component, and the magnetizing component. By decoupling these components, FOC enables precise control of the motor's behavior and improves its efficiency.

One of the key aspects of FOC is the use of Pulse Width Modulation (PWM) to generate the required motor currents. Sine/cosine PWM modulation is a technique used in FOC that provides several advantages over the more traditional step/dir and microstep methods.

Firstly, sine/cosine PWM modulation produces a smoother and more precise motor current waveform compared to step/dir and microstep. This is because the sine/cosine waveform closely matches the ideal current waveform required by the motor, resulting in less distortion and harmonic distortion. This improves the motor's efficiency and reduces heat losses and acoustic noise.

Secondly, sine/cosine PWM modulation produces less switching noise and electromagnetic interference (EMI) compared to step/dir and microstep. The smooth and precise current waveform generated by sine/cosine PWM modulation reduces the high-frequency switching noise and EMI produced by the motor.

Finally, sine/cosine PWM modulation is more efficient than step/dir and microstep, resulting in lower power consumption and longer battery life in battery-powered applications. This is because sine/cosine PWM modulation reduces the amount of power lost due to switching losses and heat generation.

In summary, FOC using sine/cosine PWM modulation provides several advantages over step/dir and microstep, including smoother and more precise current waveform, less switching noise and EMI, and improved efficiency. These advantages make FOC with sine/cosine PWM modulation a popular choice in high-performance motor control applications.