There is provided a piezoelectric actuator apparatus capable of moving an object to be driven at high velocity by using a piezoelectric element to apply a force to a driving member coupled to the object to be driven by a predetermined frictional force.

A piezoelectric actuator apparatus 100 is controlled and driven by inputting a driving voltage having a PWM waveform to a piezoelectric element 101 to which an inductor 27 and a resistor 28 are connected in series. The piezoelectric actuator apparatus 100 increases the velocity of the object to be driven 106 by adjusting respective values of the inductance L.sub.0 and the resistance R.sub.0 to control damping ratios, amplitudes, and resonance frequencies of the respective vibrations of the piezoelectric mechanical resonance and the piezoelectric electrical resonance, and inducing a response of the driving member 102 closer to sawtooth waves.

A driving-unit operation method includes: generating pulse blocks on the basis of driving pulses; and modifying a driving signal in accordance with a position error signal. In the modifying the driving signal, when the position error signal is in a first range, the shape of the driving pulses is modified so as to form a first driving-pulse shape, and the pulse-block duty cycle is set to a first pulse-block duty cycle value, whereas when the position error signal is in a second range, the shape of the driving pulses is modified so as to form a second driving-pulse shape, and the pulse-block duty cycle is set to a second pulse-block duty cycle value.

Disclosed are an ultrasonic linear motor and a method of driving the same. The ultrasonic linear motor includes a vibrator including an elastic portion and a first piezoelectric element and a second piezoelectric element which are disposed on two surfaces of the elastic portion, a moving shaft coupled to the vibrator and moved according to a displacement of the vibrator, a mover inserted into and coupled to the moving shaft, and a controller which applies a first driving pulse and a second driving pulse to the first piezoelectric element and the second piezoelectric element, wherein a frequency of the first driving pulse and a frequency of the second driving pulse are set to a frequency between a resonant frequency at which an impedance is minimum and an anti-resonant frequency at which the impedance is maximum.

In certain examples, methods and semiconductor structures are directed to operation of a piezoelectric-based device (e.g., a DC-DC converter) and such operation may involve selectively switching inputs of the piezoelectric-based device at a modulation frequency and, in response, decoupling of the modulation frequency from output power delivered by the piezoelectric-based device. In some examples, the inputs of the piezoelectric-based device are selectively switched to cause decoupling the modulation frequency from output power delivered by the piezoelectric-based device and/or cause operation of the piezoelectric-based device without spurious mode operation.

A driving circuit for driving a piezoelectric load, can include: a rechargeable power supply; a power stage circuit coupled between the rechargeable power supply and the piezoelectric load; where during a first operation interval of an operation period, the rechargeable power supply charges the piezoelectric load through the power stage circuit, such that a power supply voltage signal provided to the piezoelectric load in the first operation interval corresponds to a reference voltage in a first interval; and where during a second operation interval of the operation period, the piezoelectric load charges the rechargeable power supply through the power stage circuit, such that the power supply voltage signal in the second operation interval corresponds to the reference voltage in a second interval.

A method is provided of controlling at least two interacting piezoelectric actuators for commonly displacing an object attached thereto. The method comprises the following steps: a. Step A: applying a first cyclic drive voltage signal with a constant frequency to the first piezoelectric actuator, b. Step B: applying a second cyclic drive voltage signal with a constant frequency to said second piezoelectric actuator, whereby the frequencies of the first and second cyclic drive voltage signals are substantially identical and whereby the frequencies of the first and second cyclic drive voltage signals are substantially oppositely phased, and in which at least in a predetermined time period the cyclic drive voltage signals in step A and B are synchronized such that at least one time phase is comprised in which the drive voltage signals of the first and second piezoelectric actuators have both a gradient of decreasing or increasing the respective drive voltage signal having the same sign or one of these gradients is zero and the other is not zero.

A method for operating an electromechanical element, comprising the following steps:

by controlling a first control section (A1) which is deformable by an electrical voltage by a first voltage signal (S10) generation of adjusting movements of a friction element which is arranged on the electromechanical element and which is provided for frictional contact with an element (90) to be driven,

controlling of a second control section (A2) which is deformable by an electrical voltage by a second voltage signal (S20), which comprises a signal section (S21), the frequency of which compared to the first voltage signal (S10) is by a factor,

an actor, a drive device with an actor and a motor with a drive device and an element to be driven.

A method for controlling an inertial drive on the basis of pulse trains is disclosed. The pulse trains include pulses having sections of different gradients and having variable amplitude and/or frequency. A pulse interval occurs between the individual pulses, wherein the selected pulse duration is so short that is substantially less than the cycle duration of the natural oscillation of the system to be driven.

A capacitive actuator is connected to an output of an apparatus which is formed with a capacitor connected between an input and a reference potential, with a full bridge with four power switching elements connected in parallel with the capacitor. To charge the capacitive actuator, a control circuit first turns on the first and third power switching elements. Current then flows from the first capacitor via a coil connected between the bridge paths and energy is stored in the coil. When a maximum current value is reached, the first and third power switching elements are switched off and magnetic energy stored in the coil decays due to current flow via the diodes of the second and fourth power switching elements. This charges the capacitive actuator. The capacitive actuator is charged to a predefined voltage by possible repeated switching of the first and third power switching elements.

A driving circuit for driving a piezoelectric load, can include: a rechargeable power supply; a power stage circuit coupled between the rechargeable power supply and the piezoelectric load; where during a first operation interval of an operation period, the rechargeable power supply charges the piezoelectric load through the power stage circuit, such that a power supply voltage signal provided to the piezoelectric load in the first operation interval corresponds to a reference voltage in a first interval; and where during a second operation interval of the operation period, the piezoelectric load charges the rechargeable power supply through the power stage circuit, such that the power supply voltage signal in the second operation interval corresponds to the reference voltage in a second interval.