Carrier phase shifted pulse width modulation type digital power amplifier and power amplification method

Abstract

The invention discloses a carrier phase shifted pulse width modulation type digital power amplifier and a power amplification method. The digital power amplifier comprises a digital power amplification controller, a drive circuit module, a power amplification main circuit and a filter module; the digital power amplification controller receives externally input analog audio signals and switching signals to digitalize the analog audio signals and performs PWM (pulse width modulation) on the digitized analog audio signals and 2m digital triangular carriers having a sequential phase difference of Pi/m to generate 2m sets of PWM control signals identical in frequency and proportional to input audio amplitude in terms of duty ratio; the power amplification main circuit is connected with the 2m sets of PWM control signals output by the digital power amplification controller via the drive circuit module so as to amplify and synthesize PWM control signal power, high-power analog audio signals are generated via an LC passive low-pass filter to drive a terminal load. The carrier phase shifted pulse width modulation type digital power amplifier and the power amplification method enables effectively improved output power and reliability of digital power amplification and reduced distortion.

Description

technical field [0001] The invention belongs to the technical field of power electronics, in particular to a high-power digital power amplifier and a power amplification method. Background technique [0002] Since entering the 21st century, power electronics technology has developed rapidly, and power amplifiers have been widely used in many fields of social life. Traditional analog power amplifiers generally use power frequency transformer power supply and class AB power amplifiers, which are low in efficiency, large in size, and bulky; while digital power amplifiers have simple structure, high transmission efficiency, and easy integration, and have obvious advantages in terms of volume, weight, efficiency, and reliability. , has developed rapidly in recent years. [0003] However, due to the technical level and technical limitations of power switching devices, the power level and switching frequency of a single-module digital power amplifier are limited, and it is difficu...

AI Technical Summary

Problems solved by technology

However, due to the non-ideal switching characteristics of the devices, the equivalent input capacitance increases after the series-parallel connection, and the actual switching frequency further decreases, resulting in the deterioration of the digital power amplifier distortion and the increase in the size of the filter module; in addition, due to the characteristics of each device itself, it is impossible to completely The same, resulting in unbalanced voltage and current for each device, and even damage to the device, resulting in poor system reliability

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