High Voltage Power Amplifier for Ultrasonic Gas Detection Applications

 High-voltage power amplifiers (also known as power amplifiers, voltage amplifiers, etc., manufacturer: CoreMorrow) are amplifiers internally equipped with voltage and power amplifier circuits, which can amplify and output weak external analog signals (such as analog signals from signal generators). The gain of the high-voltage power amplifier can be as high as 180 times, and its output voltage value V, output frequency value f, etc. can be adjusted.

Before introducing how high-voltage power amplifiers are used in ultrasonic gas detection, let's first understand the ultrasonic gas detection technology and its composition principles.

Compared with the traditional ultrasonic gas detection method, the emerging technology adds a pair of ultrasonic sensors. This pair of sensors is placed in the unmixed background gas, and the distance between the sensors is exactly the same as that of the other pair of ultrasonic sensors. In this way, the synchronously emitted ultrasonic waves reach the receiving end through two equidistant paths, one path passes through the mixed gas of the concentration to be measured, and the other path passes through the pure background gas as a reference, as shown in the following figure. The phase difference and sound propagation time of the two received signals are measured at the receiving end, and the concentration value of the mixed gas can be obtained after the phase difference and time information are processed by calculation.

Schematic diagram of collection chamber

The Composition and Principle of Ultrasonic Gas Detection

Ultrasonic testing is divided into two parts: the ultrasonic sensor part and the ultrasonic drive circuit part (high-voltage power amplifier).The ultrasonic sensor part is mainly composed of two ultrasonic gas chambers: one is the reference chamber and the other is the sampling chamber.

The reference cavity is closed and filled with air. A pair of transmitting/receiving ultrasonic piezoelectric sensors are installed inside, and the pair of piezoelectric sensors are separated by a certain distance. The internal space of the sampling cavity is the same as that of the reference cavity, but its surface is open or connected to the external environment through a micro-pump, and it is always consistent with the surrounding environment. A pair of ultrasonic piezoelectric sensors and two piezoelectric sensors are also installed inside it. The distance between the sensors is strictly equal. The transmitting ultrasonic sensor converts electrical energy into acoustic energy, and the receiving sensor converts the acoustic energy into electrical signals. Since the reference cavity is airtight, the internal gas will not be polluted by the outside world. The sampling chamber samples the mixed gas from the surrounding environment. Since the difference in the propagation medium between the sensors will cause the ultrasonic propagation speed to be different, the difference in the ultrasonic propagation time in the two cavities can be compared to obtain information about the changes in the gas composition in the surrounding environment.

The circuit part mainly includes ultrasonic power transmitting circuit, ultrasonic receiving circuit, signal processing peripheral circuit and so on.

Among them, the ultrasonic power transmitting circuit is located in the high-voltage power amplifier, and the high-voltage power amplifier outputs the power required to transmit ultrasonic waves.

For the application of ultrasonic gas detection, CoreMorrow provides a variety of high-voltage power amplifiers with voltages ranging from 0 to 1800V and bandwidths up to megahertz. Typical parameters are shown in the table below.

Voltage	Current	Bandwidth （-3dB）
200Vp-p	500mA	1MHz
300Vp-p	100mA	1MHz
400Vp-p	100mA	1MHz
500Vp-p	100mA	1MHz

The characteristics of CoreMorrow’s high-voltage power amplifier are ultra-low ripple, high stability, high bandwidth, and high resolution. In ultrasonic gas detection, it can provide piezoelectric ceramic transducers with stable, high-frequency, high-voltage, and accurate high-frequency signal to realize the stable emission of ultrasonic vibration of piezoelectric ceramics.

CoreMorrow has specialized in research and development, production and sales of high-voltage power amplifiers for nearly 20 years. There are hundreds of models of high-voltage power amplifiers produced. The range of optional parameters is also very wide and can be flexibly customized.

The following is examples of CoreMorrow's high-voltage power amplifier.

• E00/E01 High Voltage Power Amplifier

CoreMorrow E00/E01 chassis-type high-voltage power amplifiers can output high voltages up to 1800V, with optional standard bandwidth up to 150kHz, customized models up to 1MHz, and gain up to 180 times.

• 400W High Voltage Power Amplifier

The output power of the E81 chassis-type high-voltage power amplifier of CoreMorrow is up to 400W, the output voltage can reach 150V, and the output bandwidth can reach 10kHz.

• Hundred-channel High-Voltage Power Amplifier

CoreMorrow’s 100-channel high-voltage power amplifier has 256 output channels or even more channels. The output voltage value of the amplifier can be controlled through the network port, and the bandwidth can reach 1kHz.

• 800V High Voltage Power Amplifier

CoreMorrow E80 high-voltage power amplifier has 4 output channels, which can amplify the output voltage of 0~10V by 80 times (ie 800V output), the bandwidth can reach 1kHz, and it can be controlled by analog or digital signals.

• Industrial High Voltage Power Amplifier

CoreMorrow E53 series of small-size high-voltage power amplifiers have 1 output channel, which can amplify 0~10V analog input signals to 0~120V or 150V and output, with a bandwidth of 10kHz, and can choose external analog signal control or PC software control.

CoreMorrow provides a large number of high-voltage power amplifiers with different parameters. Welcome to contact us and inform us of your needs, and our engineers will recommend suitable and cost-effective high-voltage power amplifiers for you.

Harbin Core Tomorrow Science & Technology Co., Ltd. is a high-tech enterprise focusing on the research and development, processing, production and sales of piezoelectric nano-motion and control systems. It provides linear motion products with micron-level stroke and nano-level positioning accuracy based on piezoelectric ceramic micro-displacement technology as well as angular motion products with milliradian deflection angle and nanoradian deflection accuracy, supporting piezoelectric controllers, high-voltage power amplifier products and related solutions, It is a pioneer in the development, innovation and exploration of China's piezoelectric nanopositioning industry.

CoreMorrow has been recognized as a national high-tech enterprise and obtained the ISO9001:2015 quality management system certification. It has a complete quality management system and strong research and development capabilities. As of the end of 2013, it has more than 20 patents, including invention patents and utility models, appearance patents, software copyrights, etc., covering key technologies in precision positioning of detection, sensing, control, and software.

Focusing on the development of the nanotechnology industry, CoreMorrow is based on precision positioning technology with independent intellectual property rights, extensively absorbing international advanced technology experience, pioneering and innovating, constantly breaking through industry technical barriers, providing personalized solutions for domestic and foreign customers, and assisting customers in overcoming technology difficulties to realize the common improvement of corporate value and customer value.