Circuit and method for energy recuperation

A method of recuperating electrical energy from a mechanical resonator, the method comprising:

• inverting the voltage across a capacitance of the mechanical resonator by:
• discharging a voltage of a first polarity held by the capacitance of the mechanical resonator to a capacitor during a first period;
• and
• charging a voltage, of opposite polarity to the first polarity, to the capacitance of the mechanical resonator during a second period using the voltage potential stored by said capacitor during the first period;
• wherein said discharging and/or charging operation comprises switching, by a control circuit, at least one switch during the first and/or second period to limit the current passing through an inductance.

A circuit for recuperating electrical energy from a mechanical resonator comprising:

• a control circuit;
• and
• a voltage inversion circuit configured to invert the voltage across a capacitance of the mechanical resonator, the voltage inversion circuit comprising:
• a capacitor;
• and
• a charge transfer circuit configured:
• to discharge a voltage of a first polarity held by the capacitance of the mechanical resonator to said capacitor during a first period;
• and
• to charge a voltage, of opposite polarity to the first polarity, to the capacitance of the mechanical resonator during a second period using the voltage potential stored by said capacitor during the first period;
• wherein the charge transfer circuit comprises an inductance and at least one switch, the control circuit being configured to switch the at least one switch during the first and/or second period to limit the current passing through the inductance,
• and wherein the control circuit is configured to control said at least one switch to conduct a current from a first node of said capacitance, through said inductance and back to a second node of said capacitance during a first portion of the first period and to conduct a current from the first node of said capacitance, through said inductance and to said capacitor during a second portion of the first period.