Constant-voltage variable-frequency DC arc generator

Abstract

The invention provides a constant-voltage variable-frequency DC arc generator, which comprises a control circuit module, a voltage conversion module, a primary boosting module, a rectifying circuit module, a secondary boosting module, a pulse excitation module and an analytical gap, and is characterized in that arc generation of the analytical gap is divided into two processes which are arc striking and arc excitation; the voltage conversion module converts AC voltage into stable DC voltage required by arc excitation and DC voltage required by a control circuit; the primary boosting module adopts a modern PWM (Pulse Width Modulation) DC boosting technology and outputs high-voltage direct current in a reversal excitation mode through a high-voltage rectifier stack and an RC integrating circuit, and an output average value of the primary boosting module is flexible and adjustable; the secondary boosting module adopts small-inductance pulse boosting mode, outputs 11-15kV pulse high voltage, and instantaneously triggers an electric arc at the analytical gap; and the pulse arc excitation module is composed of an energy storage capacitor and a secondary coil inductor of the secondary boosting module, excites the electric arc in an LC resonant mode, and adjusts the capacity of the energy storage capacitor so as to enable the electric arc to reach appropriate strength.

Description

technical field [0001] The invention belongs to the field of atomic emission spectrum analysis, in particular to a constant-voltage variable-frequency DC arc generator device. Background technique [0002] As a relatively old spectroscopic analysis technique, atomic emission spectrometry has gone through a long process of development with the continuous development of science and technology, and still occupies a relatively important position in the current atomic spectroscopic analysis. Among them, arc-induced atomic emission spectrometry is widely used in common sample detection and analysis fields such as metallurgy, geology, environment, biology and food. In addition, in the field of solution sample analysis, arc excited atomic emission spectrometry is also used as the introduction method of its sample spectrum and combined with other analytical instruments. [0003] For the technical development of atomic emission spectrometry, the improvement of excitation power often ...

AI Technical Summary

Problems solved by technology

The atomic emission spectrum excited by the AC arc generator is directly excited by the AC voltage, the spectral intensity changes with the level of the AC voltage, the stability is poor, and the background noise is large in the elemental analysis, which makes the elemental analysis difficult

DC arc generator has been widely used in the analysis of trace elements due to its simple device, easy operation, low consumption and high sensitivity. However, the atomic emission spectrum excited by it has poor controllability, instability and self-absorption. Strong shortcomings lead to poor precision of analysis results, serious matrix effect and narrow linear dynamic range, which limits the development and application of DC arc generators in the field of atomic emission spectrometry

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