An all-digital control method and device for a totem pole PFC

Abstract

The invention discloses an all-digital control method and device for a totem pole PFC, comprising: obtaining corresponding voltage and current information through a sampling module, calculating the effective value and phase value of the input voltage after digital phase locking is completed, and passing the voltage outer loop regulator and current The inner loop regulator adjusts the error signal, and uses the duty ratio feedforward to perform feedforward compensation on the output duty ratio. The present invention introduces a duty cycle feedforward, so that the current inner loop regulator only needs to suppress small signal disturbances, greatly improving the controller's ability to track power frequency sinusoidal currents, collecting input voltage zero-crossing points for digital phase-locking, and querying the sine table Obtain the phase value of the input voltage, collect the real-time value of the input voltage to calculate the effective value, and use the calculated real-time value of the input voltage as the input current command value and the input value of the feed-forward duty ratio calculation module, thereby eliminating the error caused by the sampling deviation of the input voltage The output duty cycle disturbance improves the anti-interference and stability of the digital control totem PFC.

Description

technical field [0001] The invention belongs to the field of power factor correction, and more specifically relates to a full digital control method and device of a totem pole PFC. Background technique [0002] In order to solve the harmonic pollution caused by power electronic devices to the power grid, power factor correction (PFC, PowerFactor Correction) technology has been developed rapidly. Compared with the bridged Boost PFC, the bridgeless Boost PFC has higher efficiency and smaller volume, but the traditional bridgeless Boost PFC has strong common mode interference and large EMI. Totem Boost PFC, as an evolution of bridgeless Boost PFC, has many advantages such as high efficiency, high power density, and low common-mode interference. However, the traditional Si MOSFET parasitic body diode has a long reverse recovery time and serious reverse recovery loss. It can work in CRM mode, but the input current ripple and THD are relatively large, which limits the practical a...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the defects of the prior art, the purpose of the present invention is to provide a full digital control method and device of a totem pole PFC, aiming at solving the problem that the digital control of the totem pole PFC is easily interfered and the control effect is not good in the prior art

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