Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Equalization circuit and realization method based on buck-boost transformation and bidirectional lc resonant transformation

A technology of resonant transformation and equalization circuit, applied in charge equalization circuits, circuit devices, battery circuit devices, etc., can solve the problems of slow equalization speed and low efficiency, achieve large equalization voltage difference, reduce energy waste, and zero switching loss. Effect

Active Publication Date: 2017-02-22
SHANDONG UNIV
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in this equalization circuit, when the voltage of a certain battery cell is low, while the voltage of other battery cells is in a balanced state, one switch is required to complete the equalization; High, and when the voltage of other cells is in balance, n-1 switching cycles are required to complete the balance
Therefore, for the Pack to Cell type equalization circuit, n / 2 switching cycles are needed on average, and the equalization speed is slow and the efficiency is low. It is only suitable for one or several cells in the battery pack with low voltage and other cells When the voltage is in a balanced state, it is not suitable for the case where one or several battery cell voltages are relatively high while other battery cell voltages are in a balanced state
For the Cell to Pack type equalization circuit, when the voltage of a certain battery cell is relatively high, while the voltage of other battery cells is in balance, one switch is required to complete the equalization; when the voltage of a certain battery cell is relatively high Low, and when the voltage of other battery cells is in a balanced state, n-1 switching cycles are required to complete the equalization. Therefore, the Cell to Pack type equalization circuit needs n / 2 switching cycles on average, and the equalization speed is slow and the efficiency is low. This method is only suitable for the situation that one or several cells of the battery pack have higher voltages and the voltages of other cells are in a balanced state. The case where the body voltage is in equilibrium

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Equalization circuit and realization method based on buck-boost transformation and bidirectional lc resonant transformation
  • Equalization circuit and realization method based on buck-boost transformation and bidirectional lc resonant transformation
  • Equalization circuit and realization method based on buck-boost transformation and bidirectional lc resonant transformation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0085] Such as figure 1 As shown in , it is assumed that the battery pack includes 4 battery cells, and it is assumed that B21 is the battery cell with the lowest voltage in the battery pack.

[0086] The microcontroller of the equalization circuit adopts digital signal processing DSP (TMS320F28335), which has high-precision AD sampling and PWM output; the multi-channel strobe switch adopts CD4051, which is a single 8-channel digital control analog electronic switch, with A, B and C three Binary control inputs and A total of 4 inputs, with low on-resistance and very low cut-off leakage current; the voltage detection circuit uses Linear Technology's LTC6803-1 dedicated voltage measurement chip to measure the voltage of each battery in the battery pack in real time.

[0087] The selector switch module selects a relay with a pair of normally open contacts, its model is HJR 1-2C L-05V, figure 1 Medium (S i1 , S i2 ) (i=1, 2, 3..., n) are a pair of normally open switches. The...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses an equalization circuit based on a Buck-Boost convertor and a bidirectional LC (inductance capacitance) resonant convertor as well as an implementation method. The equalization circuit comprises a microcontroller, the Buck-Boost convertor, the bidirectional LC resonant convertor, an option switch module, an equalization busbar, a battery pack and filter capacitors. According to the equalization circuit, by means of control of output voltage of the Buck-Boost convertor as well as the bidirectional LC resonant convertor, soft switching equalization of Pack to Cell or Cell to Pack can be realized, the equalization circuit has the advantages of high efficiency, simplicity in control, small size, switching loss avoidance, easiness in modularization and the like, and the defect that the traditional Pack to Cell equalization circuit cannot deal with the condition that certain cell in a pack has higher voltage while other cells are in equalization is overcome.

Description

technical field [0001] The invention relates to an equalization circuit based on Buck-Boost conversion and bidirectional LC resonance conversion and a realization method. Background technique [0002] The world is facing an unprecedented energy and environmental crisis, which has attracted worldwide attention. Electric vehicles have the characteristics of energy saving and environmental protection, which is the key way to solve this major crisis, and has become an inevitable trend in the future development of the automobile industry. Large-scale electric vehicles as mobile energy storage equipment will be an important pillar of the third industrial revolution (Energy Internet). Lithium-ion batteries are widely used as power sources in electric vehicles and hybrid electric vehicles because of their high energy density, low discharge rate and no memory effect. However, due to the technical constraints of battery manufacturing technology and power management system, a large n...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H02J7/00
CPCH02J7/0019
Inventor 张承慧商云龙李泽元崔纳新王通韩尧于广
Owner SHANDONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products