CN-121984169-A - Energy equalization system and method based on GaN high-frequency multiplexing

CN121984169ACN 121984169 ACN121984169 ACN 121984169ACN-121984169-A

Abstract

The application provides an energy balance system and method based on GaN high-frequency multiplexing, wherein the system comprises a cell group module, a matrix energy routing module, a sensing module and a central control module, wherein the cell group module is used for storing and supplying energy, the matrix energy routing module is used for receiving an energy flow decision of the central control module, a switch matrix is used for adjusting the channel state of an energy transmission channel between an energy storage cell and a GaN-based DC-DC converter according to the energy flow decision, the sensing module is used for acquiring state parameters of each energy storage cell in the cell group module, compensating the state parameters according to a preset calibration database and transmitting the compensated state parameters to the central control module, and the central control module is used for determining the charge state and the cell health of the energy storage cell according to the compensated state parameters, generating an energy flow decision according to the charge state and the cell health and transmitting the energy flow decision to the matrix energy routing module. Through the double-parameter decision of the state of charge and the health degree of the battery cell and the matrix type dynamic multiplexing architecture, the energy balance effect is improved while the miniature integration is realized.

Inventors

LI YUXIN
SU YIBO
TANG BOJIN
LIN ENDE
ZHU QIANG
YU QI
GAO CHAO

Assignees

中国长江三峡集团有限公司

Dates

Publication Date: 20260505
Application Date: 20260108

Claims (13)

1. The energy balance system based on GaN high-frequency multiplexing is characterized by comprising a battery cell group module, a matrix type energy routing module, a perception module and a central control module, wherein the matrix type energy routing module comprises a switch matrix and a GaN-based DC-DC converter; the battery cell module is used for storing and supplying energy and comprises at least one energy storage battery cell; The matrix energy routing module is used for receiving the energy flow decision of the central control module, and the switch matrix adjusts the channel state of an energy transmission channel between the energy storage battery core and the GaN-based DC-DC converter according to the energy flow decision; The sensing module is used for collecting state parameters of each energy storage battery cell in the battery cell group module, compensating the state parameters according to a preset calibration database and transmitting the compensated state parameters to the central control module; And the central control module is used for determining the state of charge and the cell health of the energy storage cell according to the compensated state parameters, generating an energy flow decision according to the state of charge and the cell health, and transmitting the energy flow decision to the matrix energy routing module so as to perform energy balance adjustment.
2. The system of claim 1, wherein the state parameters include at least voltage, current, temperature, ohmic internal resistance, and the sensing module includes at least a voltage acquisition chip, an open loop Hall current sensor, a temperature sensor, and an impedance measurement module; The voltage acquisition chip is used for acquiring the voltage of the energy storage battery cell; the open-loop Hall current sensor is used for collecting the temperature of the energy storage battery cell; The temperature sensor is used for collecting the current of the energy storage battery cell; and the impedance measurement module is used for collecting the ohmic internal resistance of the energy storage battery cell.
3. The system of claim 2, wherein the voltage acquisition chip and the temperature sensor are connected to each energy storage cell of the cell stack module by signal acquisition lines and to the monitoring ports of the switch matrix by multiplexed channels; The open-loop Hall current sensor is connected in series on an energy transmission bus between the switch matrix and the GaN-based DC-DC converter; The impedance measurement module is connected with the switch matrix through a multiplexing channel, and under the instruction of the central control module, the target energy storage battery cell is gated through the switch matrix to measure the ohmic internal resistance.
4. The system of claim 1, wherein the preset calibration database characterizes a database that simulates different environmental temperatures through a high-low temperature box, performs full-range charge-discharge cycles of different states of charge on the energy storage battery cell at each environmental temperature, collects voltage data at each state of charge, and establishes a mapping relationship between the environmental temperature and the states of charge and voltage.
5. The system of claim 1, wherein the sensing module is configured to obtain a reference voltage corresponding to a standard temperature and a standard voltage corresponding to a current temperature in a current state of charge, the standard temperature being a temperature at which the energy storage battery is rated for rated capacity and rated energy; calculating compensation quantity through a linear interpolation algorithm to compensate the state parameters; The calculation formula of the linear interpolation algorithm is as follows: ΔU = U_comp = U m + ΔU Wherein, K 1 is the temperature coefficient of the voltage at normal temperature section, which is obtained by calibration data fitting, K 2 is the temperature coefficient of the high temperature Duan Dianya, which is obtained by calibration data fitting, U_ref is the reference voltage, U 0 (T m , SOC) is the standard voltage, T m is the current real-time acquisition temperature, SOC is the current state of charge, U m is the current real-time acquisition voltage, and U_comp is the compensated voltage.
6. The system of claim 5, wherein the sensing module performs a Kalman filtering algorithm on the acquired data after compensating the state parameters according to a preset calibration database.
7. The system of claim 1, wherein the central control module comprises a central controller, a power management sub-module, and a CAN bus expansion interface; The central controller is respectively connected with the control port of the switch matrix and the control port of the GaN-based DC-DC converter through an SPI bus, and outputs the energy flow decision; the power management sub-module is connected with the central controller, the switch matrix and the GaN-based DC-DC converter to provide stable power supply for each module.
8. The system of claim 1, wherein the central control module calculates a state of charge of the energy storage cell based on an initial state of charge of the energy storage cell and current data in the state parameter, calculates an equivalent cycle number, a capacity decay rate, and an internal resistance increase rate of the energy storage cell based on the compensated state parameter, and calculates a cell health of the energy storage cell based on the equivalent cycle number, the capacity decay rate, and the internal resistance increase rate.
9. The system of claim 8, wherein the central control module calculates a state of charge of the energy storage cell as follows: Wherein, the The state of charge at time t; In order to achieve the initial state of charge, Is the real-time current at the time t, The rated capacity of the battery cell is preset; The formula for calculating the cell health degree of the energy storage cell by the central control module is as follows: N e = Σ|Q i |/(2×C n ) SOH_C = C a /C n ×100% SOH_R = R n /R a ×100% SOH = SOH_C×W_C + SOH_R×W_R The method comprises the steps of N e is equivalent cycle number, Σ|Q i | is the sum of absolute values of electric quantity accumulated in all charge and discharge cycles after the system operates, C n is the rated capacity of an electric core, SOH_C is the capacity attenuation rate, C a is the actual capacity of an energy storage electric core, SOH_R is the internal resistance increase rate, R n is the factory actual measured internal resistance of the energy storage electric core, R a is the ohmic internal resistance of the energy storage electric core, SOH is the health of the electric core, W_C is the weight coefficient of the capacity attenuation rate, and W_R is the weight coefficient of the internal resistance increase rate.
10. The system of claim 1, wherein the central control module is configured to determine a state of charge difference value between the energy storage cells in the cell group module based on the state of charge of the energy storage cells, determine an energy transfer mode of the GaN-based DC-DC converter based on the state of charge, the cell health, and the state of charge difference value, and generate the energy flow decision based on the state of charge difference value, the cell health, and the energy transfer mode.
11. The system of claim 10, wherein the central control module is configured to set the GaN-based DC-DC converter to a discharge mode if the state of charge is greater than a first charge threshold, the cell health is greater than or equal to a first health threshold, and the state of charge difference value is greater than or equal to a first difference value threshold, and to set the GaN-based DC-DC converter to a charge mode if the state of charge is less than a second charge threshold, the cell health is greater than or equal to a first health threshold, and the state of charge difference value is greater than or equal to a first difference value threshold, and to set the GaN-based DC-DC converter to a limit mode if the cell health is less than a first health threshold.
12. The system of claim 11, wherein the central control module is configured to set an energy balance priority list according to the state of charge difference value and the cell health, wherein the energy balance priority list characterizes adjustment priorities of the energy storage cells, allocate basic time slots of the energy storage cells with different priorities according to a working period of the GaN-based DC-DC converter, and sequentially generate the energy flow decision according to the basic time slots of the energy storage cells and the energy transmission modes of the GaN-based DC-DC converter according to the priorities of the energy storage cells to adjust channel states and energy transmission parameters of the energy storage cells.
13. An energy equalization method based on GaN high-frequency multiplexing, which is characterized by comprising the following steps: Collecting state parameters of each energy storage cell; Compensating the state parameters according to a preset calibration database; determining the state of charge and the health of the energy storage battery core according to the compensated state parameters; And generating an energy flow decision according to the state of charge and the health of the battery cell, and adjusting the channel state and the energy transmission parameters of the energy storage battery cell through the energy flow decision so as to perform energy balance adjustment.

Description

Energy equalization system and method based on GaN high-frequency multiplexing Technical Field The application relates to the technical field of cell equalization of energy storage systems, in particular to an energy equalization system and method based on GaN high-frequency multiplexing. Background In an energy storage system, a battery pack is formed by connecting a plurality of battery cells in series or in parallel, and the consistency difference between the battery cells is a core bottleneck which restricts the performance and service life of the battery pack. The current mainstream cell balancing technology in the industry is mainly divided into two main types, namely passive balancing and active balancing, wherein the passive balancing scheme is used for realizing balancing by using a resistor to consume excess energy when the voltage of the cell is too high by connecting dissipation elements such as a resistor, a capacitor and the like in parallel at two ends of each cell, and the active balancing scheme is used for realizing peak clipping and valley filling through energy transfer so as to avoid energy waste. However, the passive equalization technology cannot supplement energy to the low-power battery cells, the equalization effect is limited, the active equalization scheme has the problems of complex structure, high cost, response lag and the like, and has the problems that miniaturization integration is difficult, state monitoring precision is low, detail differences such as a battery cell SOC (State of Charge) are difficult to accurately identify, equalization strategy lag or misjudgment is caused, and equalization effect is affected. Disclosure of Invention The embodiment of the application aims to provide an energy equalization system and method based on GaN high-frequency multiplexing, which can solve the problems that the equalization strategy is lagged or misjudged and the equalization effect is influenced because the prior art is difficult to integrate in a miniaturized way, the state monitoring precision is low, and the detail differences such as an SOC (state of charge) and the like are difficult to accurately identify. In a first aspect, the embodiment of the application provides an energy balance system based on GaN high-frequency multiplexing, which comprises a battery cell group module, a matrix energy routing module, a perception module and a central control module, wherein the matrix energy routing module comprises a switch matrix and a GaN-based DC-DC converter; the battery cell module is used for storing and supplying energy and comprises at least one energy storage battery cell; The matrix energy routing module is used for receiving the energy flow decision of the central control module, and the switch matrix adjusts the channel state of an energy transmission channel between the energy storage battery core and the GaN-based DC-DC converter according to the energy flow decision; The sensing module is used for collecting state parameters of each energy storage battery cell in the battery cell group module, compensating the state parameters according to a preset calibration database and transmitting the compensated state parameters to the central control module; And the central control module is used for determining the state of charge and the cell health of the energy storage cell according to the compensated state parameters, generating an energy flow decision according to the state of charge and the cell health, and transmitting the energy flow decision to the matrix energy routing module so as to perform energy balance adjustment. Optionally, the state parameters at least comprise voltage, current, temperature and ohmic internal resistance, and the sensing module at least comprises a voltage acquisition chip, an open-loop Hall current sensor, a temperature sensor and an impedance measuring module; The voltage acquisition chip is used for acquiring the voltage of the energy storage battery cell; the open-loop Hall current sensor is used for collecting the temperature of the energy storage battery cell; The temperature sensor is used for collecting the current of the energy storage battery cell; and the impedance measurement module is used for collecting the ohmic internal resistance of the energy storage battery cell. Optionally, the voltage acquisition chip and the temperature sensor are connected with each energy storage cell of the cell group module through a signal acquisition line and are connected with a monitoring port of the switch matrix through a multiplexing channel; The open-loop Hall current sensor is connected in series on an energy transmission bus between the switch matrix and the GaN-based DC-DC converter; The impedance measurement module is connected with the switch matrix through a multiplexing channel, and under the instruction of the central control module, the target energy storage battery cell is gated through the switch matrix to measure the ohmic inter