Voltage-sharing control method for ISOS combined-type DC/DC converter

Abstract

The invention discloses an input voltage-sharing control method for an ISOS combined-type DC / DC converter, and the method comprises the steps: judging whether a single-module converter deviates from avoltage balancing working point or not through the independent calculation of the input voltage of the converter; employing an extended phase shift control method when one DC / DC converter deviates from the voltage balancing working point, adjusting the input voltage of the DC / DC converter through closed-loop control, enabling the DC / DC converter to return to the voltage balancing working point, and achieving the input voltage sharing. The extended phase shift control method can improve the power backflow in DC / DC conversion. For the ISOS combined-type DC / DC converter, the control method provided by the invention can adjust the transmission power, guarantees the power balancing among all modules, and achieves the voltage sharing and the stable output voltage. The method is high in practicality, is simple in control and is high in reliability.

Description

technical field [0001] The invention relates to the field of DC conversion, in particular to a voltage equalization control method for an ISOS combined DC / DC converter. Background technique [0002] With the continuous development of the current industry, the human demand for electricity is increasing day by day. There are more and more deficiencies in the traditional AC transmission technology, which makes the DC transmission technology develop rapidly. Compared with AC transmission, DC transmission overcomes the inductance loss in the transmission line, only the loss of wire resistance; the line cost and operating cost of DC transmission are lower, and relevant data show that within a certain power range, the equivalent distance of DC transmission It is much larger than AC transmission, and DC transmission is easier to realize underground or submarine cable transmission, so the necessity of developing DC transmission can be foreseen. [0003] As the core content of DC tr...

AI Technical Summary

Problems solved by technology

The above method has good versatility for non-phase-shifting DC / DC converters, but when the phase-shifting control DC / DC converter is working, power backflow will be generated, which will affect the voltage equalization effect, resulting in that the input and output voltages of the system cannot be equally divided.

[0006] For the ISOS combined DC / DC converter, there are many voltage equalization control methods currently proposed, but these methods have only one control quantity, and the application in phase-shifting DC / DC conversion will cause a large power backflow problem

Images