Synthesis of drive systems of infinite disturbance rejection ratio and zero-dynamics/instantaneous response

A method for synthesizing electric motor drive system of infinite disturbance rejection ratio and zero dynamics comprising:

• accepting a source of electrical energy of a constant voltage at an input to a power converter,
• coupling mechanically a shaft of an electric motor to a load to be driven at an output,
• controlling a power flow from said input to said output,
• modulating said power converter for the control of said power flow in a pulse width modulation manner,
• supplying a total control signal for modulating said power converter,
• supplying position feedback pulses,
• feeding back said position feedback pulses and comparing their frequency and phase with frequency and phase of position command pulses in a phase frequency detector in a negative feedback manner;
• thereby producing a position error voltage proportional to a difference in frequency and phase between said position command pulses and said position feedback pulses;
• supplying a position command obtained as a voltage potential,
• passing said position command through a position direct path circuit;
• thereby producing said position command pulses,
• passing said position command through a differentiation circuit;
• thereby producing a velocity signal voltage,
• passing said velocity signal voltage through a velocity direct path circuit;
• thereby producing a velocity command voltage,
• passing said velocity signal voltage through a feedforward circuit;
• thereby producing a feedforward signal,
• supplying a velocity feedback signal,
• feeding back said velocity feedback signal and summing it with said velocity command voltage and said position error voltage in a negative feedback manner;
• thereby producing a resulting error voltage,
• passing said resulting error voltage through a cascade connection of a stabilizing network and a control circuit;
• thereby producing a control signal proportional to the algebraic sum of said velocity command voltage and said velocity feedback signal and said position error voltage,
• sensing a current through said electric motor,
• feeding back the sensed current signal through a current feedback circuit in a positive feedback loop with respect to said control signal and said feedforward signal and summing the sensed current signal with said control signal and said feedforward signal,
• supplying said total control signal, obtained as the sum of said control signal and said feedforward signal and the current signal fed through said current feedback circuit, for modulating said power converter for the control of the flow of power from the input electrical source to the output mechanical load, whereby all electrical and mechanical time constants associated with said electric motor and with the mechanical load are brought to zero yielding an infinite disturbance rejection ratio by making an angular shaft position and speed independent of said load and yielding a zero dynamics by cancelling remaining time constants in the system and making a transfer function from said position command to said angular shaft position a constant and therefore of zero dynamics.