Research And Development Of High Voltage Switching Power Amplifier

Vibration test, as an effective method for simulating the vibration environment, and testing the reliability and dynamic strength of products, has been wildly used in the product’s performance assessment and identification of dynamic strength.Power amplifier is the necessary equipment in vibration test system.At present,the switching power amplifier is used most widely as a power amplifier,and its performance and the matching conditions with the vibration table is directly related to the performance of vibration test system.In recent years,development of Electrodynamic Vibration Shaker,large-tonnage of more than20tons,provides conditions of comprehensive stress environmental testing for satellites and missiles and other large equipments,also make demand for high-power high-voltage switching power amplifiers.With respect to the demand of high-power high-voltage switching power amplifier, this paper presents a new method to develop the switching amplifier, and describes it in detail.Amplifier mainly consists of DC power, power circuit, control circuit, the output filter,and other parts.The DC power of this system use three-phase full-bridge controlled rectifier circuits,insulated gate bipolar transistor (IGBT) with full controller parts constitute the full-bridge inverter of power circuits,pulse width modulation (PWM) integrated control technology is applied in control circuit, second-order LC low-pass filter is adopted in output filter to achieve high-voltage high-power output.In addition,high-power IGBT drive circuits,unipolar PWM modulation frequency, IGBT thermal discharge and electromagnetic compatibility and other aspects of are also designed in detailed in this paper.The prototype developed achieve good performance by commissioning, according to test results,precise performance indicators of high-power high-voltage switching power amplifier was obtained,the advantages and disadvantages were summarized,a theoretical basis and practical experience were provided for the future design of more powerful amplifier.