High-voltage broadband amplifier for a frequency range of up to 100 kHz and a maximum output voltage of up to 1000 V

The main purpose of the high-voltage broadband amplifier is to provide metrological support for thermoelectric converters, in particular the PNTE-12 and others, with conversion limits of 300 V, 500 V, and 1000 V. Therefore, the development of an amplifier capable of operating across a wide frequency and voltage range is a relevant task. This paper provides a detailed overview of the possibilities for improving the metrological characteristics of specialized extension units for the frequency and dynamic ranges of AC voltage standards used in metrological systems. The operation of these units in the frequency range up to 100 kHz and at maximum output voltages up to 1000 V is considered, which is particularly relevant for modern high-precision metrological and calibration laboratories. Based on a matrix equation, analytical expressions to describe the static and dynamic characteristics of non-inverting amplifiers with independent feedback loops are proposed. These expressions make it possible to predict and optimize amplifier performance, particularly in terms of amplitude stability, phase shifts, and signal transmission linearity across a wide range of operating frequencies and amplitudes. The paper presents the results of an experimental study on a high-voltage broadband amplifier that provides a voltage transfer uncertainty not exceeding 15 ppm across the full frequency range of up to 100 kHz at a maximum output voltage of up to 1000 V. Experimental setups and measurement methods are described, and the factors affecting the accuracy and stability of amplifier operation are analysed. A high-voltage broadband amplifier with a maximum output voltage of up to 1000 V and operating within a frequency range of 0 to 100 kHz was developed using non-inverting stages with independent feedback loops. The results obtained made it possible to implement this amplifier as part of the military AC voltage reference unit VVTU-08-07-01-09 for calibrating high-voltage thermoelectric converters, confirming the high metrological reliability, stability, and practical value of the developed technical solutions.