Method for controlling drive pulses of DAB type bidirectional isolation DC-DC converter

Abstract

The invention relates to a method for controlling drive pulses of a DAB type bidirectional isolation DC-DC converter. The method for controlling the drive pulses of the DAB type bidirectional isolation DC-DC converter comprises the steps of firstly, carrying out drive pulse control on the DAB type bidirectional isolation DC-DC converter based on a drive pulse working principle; and then inferring relevant formulas in the mode of control, and carrying out characteristic analysis and verification. The method for controlling the drive pulses of the DAB type bidirectional isolation DC-DC converter only needs to control a single variable, is simple and practical, applicable to the state of light load of a system, simple in algorithm, convenient to achieve, and prone to feedback regulation, reduces stress of devices, and effectively improves system efficiency when the system is in light load.

Description

technical field [0001] The invention relates to a modulation technology of a switching power tube of a bidirectional isolation DC-DC converter, in particular to a driving pulse control method of a DAB type bidirectional isolation DC-DC converter. Background technique [0002] DAB type DC-DC converter is widely used in uninterruptible power supply (UPS), clean energy conversion system, energy double-fed system, And electric vehicle lithium battery charging and discharging equipment, etc. Its basic topology is as figure 1 As shown, the full bridge B on the primary side 1 Through the transformer and the secondary full bridge B 2 Each full bridge is composed of 4 controllable switch tubes and anti-parallel diodes. The transformer T ensures electrical isolation, and the transformation ratio is n:1. L is the leakage inductance of the transformer or an external equivalent leakage inductance, which plays a role in the circuit. The role of transferring energy. [0003] The loss ...

AI Technical Summary

Problems solved by technology

[0005] 1. The peak current I flowing through the transformer, leakage inductance and switching devices peak and current rms value I rms If it is too large, the stress on the related devices will increase, which will increase the cost of the device

[0006] 2. The voltage at both ends of the leakage inductance is large, the maximum rise rate of the inductor current is large, and the external electromagnetic interference to the system increases, resulting in a decrease in system reliability

[0007] 3. Current peak I peak and current rms value I rms And the reactive power Q of the system L If it is too large, the system loss will increase and the system efficiency will be low

[0008] The current dual-phase-shift control method solves the above problems under the premise of ensuring power output by controlling two phase-shift angle variables, but the dual-phase-shift control method needs to control two phase-shift angle variables, which requires a large amount of calculation and complicated control methods. , not easy for feedback adjustment and engineering implementation

Images