LC series resonance high frequency chain matrix-type inverter topology and resonance modulation method thereof

Abstract

The present invention provides a LC series resonance high frequency chain matrix-type inverter topology and a resonance modulation method thereof. The topology comprises of a full bridge LC series resonance inverter, a high-frequency transformer T, a matrix converter and a CL-type filter which are connected in order. The modulation method is configured to process the SPWM wave through separation and link semi-excitation modulation logics to obtain driving signals of a transformer pre-stage LC series resonance inverter and a transformer post-stage matrix converter so as to allow the work duty ratio of the transformer pre-stage resonance circuit excitation resonance work state in the resonance half period to be controllable and realize the control of energy side transmission to the output load. The transformer post-stage matrix converter is modulated and decoupled to two common current-type inverters for controlling, a switch tube performs switching during the zero current outputting to realize zero current switching to avoid causing voltage overshoot problems and realize energy bidirectional flow and four-quadrant operation. The power transformation grades are few, the control method is simple, the circuit stability is high, and the like.

Description

technical field [0001] The invention relates to the field of power electronic power converter modulation and control, in particular to a decoupled coupling half-excitation resonance modulation method for a single-phase LC series resonance type high-frequency chain matrix inverter. Background technique [0002] An inverter is a topological device that converts DC power into AC power. The high-frequency link inverter uses high-frequency transformers instead of power-frequency transformers to overcome the shortcomings of traditional transformers such as large volume, large noise, and high cost. The conversion process of the high-frequency chain matrix inverter has three power characteristics of DC / HFAC / LFAC, among which, HFAC: high-frequency AC, LFAC: low-frequency AC. It can be seen that DC / AC, that is, DC / AC inverter link, appears in this type of inverter, which is located on the primary side of the transformer, and AC / AC, that is, AC / AC conversion link, which is also often ...

AI Technical Summary

Problems solved by technology

At present, there are mainly the following safe commutation strategies: ① By adding active clamps to suppress voltage overshoot, soft switching can be realized, but the introduced clamp circuit increases the cost, and the added controllable power tube also makes the control more efficient. Complex; ②The unipolar and bipolar phase-shift control strategy realizes the natural commutation of the inductor current by means of the commutation overlap of the cycloconverter, and realizes the ZVS of the power tube, but there are problems such as difficult control of the commutation overlap time; ③The series resonant circuit is introduced into the front-end inverter to realize the soft commutation of the power tube. At this time, the switching of the power tube is required to occur at the moment of zero current, and the control of the output energy needs to judge the resonant working state of the resonant circuit, which makes the control method complicated

[0004] However, although the above strategy can achieve safe commutation, it makes the modulation and control of the inverter more complex, resulting in reduced system reliability and affecting the popularization and use of this type of converter.

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