Application Cases

【Overview】
In 2024, a research team from Hefei University of Technology published a paper titled "An Improved Equivalent Circuit Model of a V-Shaped Single-Mode Linear Ultrasonic Motor and a Novel Driving Mode". In this study, the Aigtek ATA-2042 high-voltage amplifier was used to build an ultrasonic motor experimental system. This paper proposes an improved equivalent circuit model that accounts for real contact-based operating conditions, introducing a novel operating mode for driving the V-shaped transducer. Under contact-based boundary conditions, the electromechanical coupling characteristics of the stator are modeled using a modified equivalent admittance-type circuit, where variable contact stiffness and losses are characterized between the stator and rotor. The friction drive mechanism is represented by a silicon-controlled rectifier circuit to characterize intermittent drive characteristics, preliminarily capturing the nonlinear relationship between motor characteristics and contact-based operating conditions from a circuit perspective. Through parameter identification and modification, loss distribution, admittance characteristic analysis, and evaluation of output and control characteristics, the advantages and applications of the circuit model are demonstrated using a single-mode linear ultrasonic motor (SMLUM) as an example.

Experiment Name: Ultrasonic Motor Drive

Research Direction: Ultrasonic motor theory and application technology

Experimental Content:
Ultrasonic motors are novel micro-special motors based on the inverse piezoelectric effect and mechanical resonance principles, achieving power output directly through stator/rotor friction transmission. The drive section typically requires ultrasonic-frequency sine/square wave voltages exceeding 100 Vpp. The tested ultrasonic motor required sinusoidal or square wave drive signals with a peak-to-peak voltage range of 100 Vpp–300 Vpp and a frequency of approximately 40 kHz. In this experiment, a signal generator was used to produce sine/square wave voltage signals, which were then amplified by an ATA-2042 power amplifier before being applied to the electrodes of the piezoelectric ceramic on the ultrasonic motor stator. This excited a single-mode vibration mode in the V-shaped stator, generating a diagonal drive trajectory at the driving foot. Using the friction transmission mechanism, the linear stage was driven to achieve high-precision reciprocating linear motion.

Testing Equipment:
Signal generator, ATA-2042 high-voltage amplifier, oscilloscope, current probe, laser displacement sensor, etc.

Experimental Procedure:

Figure: Schematic Diagram of the Experimental Test System

Figure: Physical Setup of the Experimental Test System

The V-shaped stator single-mode linear ultrasonic motor requires only a single-phase, high-voltage, high-frequency alternating voltage excitation to achieve linear motion. To test the electrical and mechanical characteristics of the experimental prototype, an experimental platform was built using a signal generator, ATA-2042 high-voltage amplifier, oscilloscope, current probe, laser displacement sensor, and dynamometer to measure the motor's phase current, phase voltage, output speed, step displacement, and load capacity.

Experimental Results:

Figure: Experimental Results

The experiments show that the drive section composed of the signal generator and power amplifier can generate high-frequency drive voltages with adjustable sine/square wave amplitude and frequency, successfully driving the V-shaped stator linear ultrasonic motor operating in single-mode. The measured mechanical characteristics of the motor indicate that under a single-phase excitation voltage of 200 Vpp, the no-load output speed of the motor exceeded 700 mm/s, the maximum thrust exceeded 7 N, and the minimum open-loop step displacement reached 3.56 μm.

Advantages of Aigtek Amplifiers in This Application:

1. High voltage output capability – Provides the driving voltage required to achieve high speed and high thrust output from the motor.

2. Wide bandwidth and high-frequency response – Precisely matches the ultrasonic frequency, ensuring stable single-mode excitation.

3. Low distortion and waveform fidelity – Improves control accuracy.

Reference: An Improved Equivalent Circuit Model of a V-Shaped Single-Mode Linear Ultrasonic Motor and a Novel Driving Mode

Recommended Product: ATA-2042 High-Voltage Amplifier

Figure: ATA-2042 High-Voltage Amplifier Specifications and Parameters