Two level inverter type MAO power source and output regulation control method thereof

Abstract

The invention provides a two-stage inversion type micro-arc oxidation power supply, comprising a main circuit, a control system and a human-computer interaction device, wherein, the main circuit comprises a power supply switch, an input rectifying and filtering circuit, a power inverter circuit, a high frequency transformer, an output rectifying and filtering circuit and a chopper inverter circuit. The control system comprises a control transformer and a control circuit. The human-computer interaction device comprises a keyboard and a display. The control transformer and the input rectifying and filtering circuit are respectively connected with a power frequency AC network by the power supply switch. The chopper inverter circuit is connected with a load. The control circuit is respectively connected with the power inverter circuit, the chopper inverter circuit, the keyboard, the display and the output end of the output rectifying and filtering circuit. The two-stage inversion type micro-arc oxidation power supply is characterized by high control precision, rapid response speed and multiple outputs. Furthermore, the technique stability is good and the intelligent monitoring is adopted, therefore, high efficiency, high frequency and intelligence can be realized.

Description

technical field [0001] The invention relates to a micro-arc oxidation power supply for material surface treatment, in particular to a two-stage inverter micro-arc oxidation power supply and an output regulation control method thereof. Background technique [0002] Micro-arc oxidation is a new and promising material surface treatment technology, and the power supply of micro-arc oxidation is one of the key factors affecting the quality of micro-arc oxidation film. The micro-arc oxidation power supply has various modes such as DC, unidirectional pulse, AC symmetry and AC asymmetry, and the power supply using the AC asymmetric working mode is an important development direction of the micro-arc oxidation technology. At present, micro-arc oxidation power supplies with AC asymmetric pulse output characteristics have also been developed in China, mainly including thyristor rectifier power supplies, diode rectifier power supplies, bipolar inverter voltage regulation power supplies a...

AI Technical Summary

Problems solved by technology

[0009] (1) The switching frequency is low, generally below 1kHz, and the precision of energy output control and time control is low;

[0010] (2) The primary stage of most power supplies uses power frequency rectifier transformers, which are bulky, heavy, low in efficiency, and consumable; and even if inverter voltage regulation is used, it is divided into Yin and Yang stages, which makes the cost of power supply high and the loss is large;

[0011] (3) Some power supplies are open-loop systems, some with current and voltage feedback control, and the stability of the power supply is not enough;

[0012] (4) Positive and negative pulses generally need to use different transformers to obtain different outputs, and the control circuit is complicated;

[0013] (5) The switching device in the post-stage chopper circuit is in a hard switching state, and the switching loss is large

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