Switched inductor AC-DC circuit and inductance value self-adaptive control method thereof

Abstract

The invention discloses a switched inductor AC-DC circuit and an inductance value self-adaptive control method thereof. The switched inductor AC-DC circuit comprises a filter circuit, a rectifying circuit, a first-stage interleaving circuit and a second-stage interleaving circuit, wherein the filter circuit is used for filtering an input alternating current power supply; the rectifying circuit isused for rectifying the filtered alternating-current voltage; the first-stage interleaving circuit is used for carrying out first boosting and first power factor correction on the direct-current voltage; the second-stage interleaving circuit is used for carrying out second boosting and second power factor correction on the direct-current voltage; and the switching period of the second-stage interleaving circuit is lagged behind the switching period of the first-stage interleaving circuit. The method comprises the steps of determining parameters; detecting real-time voltage deviation; calculating the maximum duty ratio of the power switch according to a DCM mode principle; calculating a duty ratio corresponding to the power switch; calculating the duty ratio and the phase shift of the corresponding power switch; and controlling the on-off of the corresponding power switch. According to the invention, voltage impact caused by sudden change of current can be avoided, and the loading capacity is improved.

Description

technical field [0001] The invention relates to the technical field of power electronic conversion, in particular to a switched inductance AC-DC circuit and an inductance self-adaptive control method thereof. Background technique [0002] In the Proceedings of the 13th IEEE Conference on Industrial Electronics and Applications (ICIEA2018) in 2018, Wang Faqiang and others proposed a switched-inductor (Switched-inductor) power factor correction circuit (PFC), that is, a single-phase AC-DC circuit, including Two energy storage branches and one freewheeling branch have the characteristics of fewer components, no step-up transformer, high voltage gain and unit power factor of the grid side. [0003] In one switching cycle, the working process of the entire AC-DC circuit is divided into three stages: (1) The two power switches of the two energy storage branches are turned on at the same time, the two inductors are charged independently, the current rises and the energy is stored; ...

AI Technical Summary

Problems solved by technology

Only when discontinuous current mode (DCM) is used, when the inductance value is different, there is a control algorithm that may enable the AC-DC circuit to work, but certain conditions must also be met to prevent the circuit from entering CCM

That is, when the inductance values ​​are different, it must be ensured that the two inductors are discharged at the same time and the discharge instantaneous current is equal, and a margin is reserved to accommodate heavy loads, high switching frequency, network voltage RMS drop and inductance value increase. Potential CCM, which is The only solution, but this information is not disclosed in the existing literature

[0007] In addition, the switched-inductor power factor correction circuit (PFC) proposed by Wang Faqiang et al. has a low load capacity and does not provide a grid-side filter circuit. Due to the use of DCM, the design of the network current filter is more difficult. Therefore, It is necessary to design an interleaved structure in order to solve the difficulty of carrying capacity and grid-side filter circuit design

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