Cascaded control based super capacitor charging method and device

Abstract

The invention discloses a cascaded control based super capacitor charging method and device. The method comprises the steps that 1) multiple sub-charging modules are arranged in parallel between a DCpower supply and a super capacity module to serve as the charging device; S2) the practical value of the output voltage of the charging device is collected, a difference between the practical output voltage value and a voltage reference value is calculated, a voltage loop compensator calculates a current reference value of the sub-charging modules, and the current reference value surfaces as output data of a voltage loop in the outer ring; and 3) the current reference value is obtained from the voltage loop in the outer ring, a local practical output current value and practical output currentvalues of neighbor sub-charging modules are obtained, a coordinated control module calculates a current error signal according to the obtained current data, a current loop compensator calculates the duty ratio of a PWM signal, and the PWM signal is generated to control the output voltage and current of the local sub-charging module. Currents of the sub-charging modules are balanced, and the charging efficiency of the super capacitor module is improved substantially.

Description

technical field [0001] The invention belongs to the field of supercapacitor charging, and in particular relates to a supercapacitor charging method based on cascade control and a charging device thereof. Background technique [0002] Today's cities need zero-emission, low-noise, and efficient transportation solutions, and require this type of transportation to occupy as little space as possible for urban public transportation. Supercapacitor urban rail is a mode of transportation that meets the requirements. Its only energy source is the on-board supercapacitor energy storage system. This new type of urban rail has many advantages, such as saving the cost of equipment such as pantographs; Improved energy utilization; ability to work under harsh environmental conditions. [0003] However, the on-board supercapacitor energy storage system often needs to be charged in a short time, that is to say, a large amount of electric energy can be obtained in a short time, which brings ...

AI Technical Summary

Problems solved by technology

Although the distributed parallel circuit structure can reduce the voltage and current stress of switching devices and avoid single point failure, it will make the system more complex and increase the difficulty of system control strategy design

[0004] In addition, for supercapacitors, most current charging strategies are constant current charging, and there is a problem of voltage drop at the end of the charging process, which causes insufficient utilization of supercapacitors and reduces the charging efficiency of the system

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