CN210444027U

CN210444027U - Hybrid equalization circuit and daisy chain communication hybrid equalization battery equalization control device

Info

Publication number: CN210444027U
Application number: CN201822112192.1U
Authority: CN
Inventors: 林田生; 郑庆飞
Original assignee: Dongguan Powerwise Technology Co
Current assignee: Dongguan Powerwise Technology Co
Priority date: 2018-12-14
Filing date: 2018-12-14
Publication date: 2020-05-01
Anticipated expiration: 2028-12-14

Abstract

The utility model discloses a mix equalizer circuit for the equilibrium of a plurality of electric cores in control group battery the inside, include correspond a plurality of equalizing unit of being connected with a plurality of electric cores, with a plurality of the simulation front end management module that equalizing unit electricity is connected to and sampling resistance, acquisition circuit connects between equalizing unit's negative pole and group battery negative pole, gathers a plurality ofly equalizing unit's equalizing current carries to simulation front end management module, and the PWM signal that simulation front end management module corresponds to equalizing unit's switch tube output is in order to control equalizing unit's switch tube break-make, and the foundation equalizing current feedback control PWM signal's cycle is in order to make equalizing current invariable. The utility model discloses detect the switching on cycle of switch tube in balanced current and the balanced unit of feedback control to make balanced current invariable. The utility model also discloses a balanced controlling means of mixed balanced battery of daisy chain communication.

Description

Hybrid equalization circuit and daisy chain communication hybrid equalization battery equalization control device

Technical Field

The utility model relates to a battery management technology field especially relates to a mix equalizer circuit and mix balanced battery equalization control device.

Background

The inconsistency of the battery pack needs to be maintained by using an equalization technology, and the existing equalization technology comprises passive equalization and active equalization. The passive equalization only consumes energy by discharging, can start multi-path equalization simultaneously, and has simple control and low cost. The active equalization is an energy transfer mode, cannot start multi-path equalization simultaneously, and is complex to control and high in cost. Both equalization methods have their own advantages and disadvantages, and thus a hybrid equalization method has emerged.

However, in the existing hybrid balancing mode, the on-off of the switching tube in the balancing circuit is often controlled by only collecting the voltage, the current and the charging and discharging current of the whole battery, and the magnitude of the balancing current cannot be determined in the whole process, so that the constant balancing current cannot be ensured, and the balancing effect is poor.

Therefore, there is a need for an equalization circuit and an equalization control system that can solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a hybrid equalizing circuit can realize initiative equilibrium, passive equilibrium simultaneously, and when the initiative was balanced, can accurate detection balanced current and feedback control in order to keep balanced current invariable.

In order to realize the purpose, the utility model discloses a hybrid equalizing circuit, which is used for controlling the equalization of a plurality of battery cells in a battery pack and further comprises sampling resistors, wherein each equalizing unit comprises a first switch, an energy conversion circuit and a second switch, the first side and the second side of the energy conversion circuit are coupled, the first switch is connected between the anode and the cathode of the corresponding battery cell after being connected in series with the first side of the energy conversion circuit, the second switch is connected between the anode of the battery pack and the sampling resistor after being connected in series with the second side of the energy conversion circuit, the other end of the sampling resistor is connected with the cathode of the battery pack so as to collect the equalizing currents of a plurality of equalizing units and transmit the equalizing currents to the analog front-end management module, the analog front-end management module outputs corresponding PWM signals to the first switch and the second switch to control the on-off of the first switch and the second switch, and controlling the period of the PWM signal according to the equalization current feedback so that the equalization current is constant.

Compared with the prior art, the utility model discloses locate energy conversion circuit's level and group battery total negative pole with collection resistance between to balanced current when gathering the initiative equilibrium forms a closed loop control chain according to the conduction cycle of the first switch of balanced current feedback control and second switch, can real-time quick adjustment PWM signal's duty cycle, and the balanced current of control is invariable all the time. Furthermore, the utility model discloses can control simulation front end management module and close all second switches, the break-make of corresponding control first switch is in order to realize passive equilibrium, and first switch, the second switch correspondence that can also the same equalizing unit of active control switch on and close to realize the initiative equilibrium, thereby accomplish and mix the equilibrium.

Preferably, the analog front end management module stops outputting the PWM signal when the equalizing current exceeds a preset threshold until the equalizing current does not exceed the preset threshold.

Preferably, the analog front end management module includes a current comparison unit and a PWM signal output interface, the analog front end management module outputs the PWM signal according to the PWM signal output interface, one end of the current comparison unit is connected to the sampling resistor, the other end of the current comparison unit is connected to the PWM signal output interface, and when the equalizing current is greater than a preset value, the current comparison unit controls the PWM signal output interface to stop outputting the PWM signal until the equalizing current is less than the preset value.

Preferably, the energy conversion circuit is a flyback transformer.

Preferably, the analog front end management module is connected to the plurality of battery cells to acquire electrical signals of the plurality of battery cells, and generates corresponding PWM signals according to the electrical signals to control on/off of the first switches and the second switches in the plurality of equalization units.

Specifically, when any one of the battery cells is subjected to active charge equalization, the analog front-end management module controls the second switch and the first switch of the battery cell to be sequentially switched on for a preset time and then switched off, and the first switch and the second switch are prohibited from being switched on simultaneously; when any one of the battery cells is subjected to active discharge equalization, the analog front-end management module controls the first switch and the second switch of the battery cells to be sequentially switched on and switched off after preset time, and the first switch and the second switch are forbidden to be switched on simultaneously.

More specifically, the analog front end management module controls the second switch to be turned off and controls the first switch to be turned on when the battery cell performs active charge equalization, and the analog front end management module controls the first switch to be turned off and controls the second switch to be turned on when the battery cell performs active discharge equalization.

Preferably, the analog front-end management module further controls second switches of all the equalizing units in the hybrid equalizing circuit to be turned off according to an external control signal, and controls one or more equalizing units to be turned on according to an electrical signal of the battery cell.

Preferably, each of the balancing units further includes a current-limiting resistor, the current-limiting resistor is connected in series to the first switch and the branch where the first side of the energy conversion circuit is located, the current-limiting resistor effectively limits the maximum on current, and the first switches of the balancing units corresponding to the plurality of battery cells in all the battery packs can be allowed to be turned on, so that multi-path passive balancing is realized, and a battery short circuit cannot be caused.

Preferably, the hybrid equalizing circuit further comprises a fuse and a bidirectional TVS tube, the fuse is connected in series between the positive electrode of the battery pack and the plurality of equalizing units, and the bidirectional TVS tube is connected between the positive electrode of the battery pack and the ground.

The utility model also discloses a daisy chain communication mixes balanced battery equalizing control device, including host system and a plurality of mix equalizer circuit, mix equalizer circuit as above, a plurality of mix equalizer circuit through the daisy chain communication mode cascade in proper order the back with host system links to each other, host system manages a plurality of mix equalizer circuit.

Drawings

Fig. 1 is a block diagram of the daisy chain communication hybrid balanced battery balancing control device of the present invention.

Fig. 2 is a partial structural block diagram of the hybrid equalizing circuit of the present invention.

Fig. 3 is a partial circuit diagram of the hybrid equalizing circuit of the present invention.

Fig. 4 is a wiring diagram of the analog front end management module.

Fig. 5 is a partial block diagram of the analog front end management module according to the present invention.

Detailed Description

In order to explain technical contents, structural features, and objects and effects of the present invention in detail, the following description is given in conjunction with the embodiments and the accompanying drawings.

Referring to fig. 1, the utility model also discloses a mixed balanced battery equalizing control device 100 of daisy chain communication, including host system 30 and a plurality of hybrid equalizing circuit 10, a plurality of hybrid equalizing circuit 20 cascade the back in proper order through the daisy chain communication mode and link to each other with host system 10, a plurality of hybrid equalizing circuit of host system 10 management, a plurality of hybrid equalizing circuit 20 will detect the signal of telecommunication and balanced information carry to the hybrid equalizing circuit 20 of last level, until carrying to host system 30, host system 30 sends control signal and carries to corresponding in the hybrid equalizing circuit 10 through the daisy chain communication line.

Referring to fig. 1 to 4, the hybrid equalization circuit 10 is configured to control equalization of a plurality of battery cells (B1-B6) in a battery pack 20, and includes a plurality of equalization units 11 correspondingly connected to the plurality of battery cells (B1-B6), an analog front end management module 12 electrically connected to the plurality of equalization units 11, and a sampling resistor RS. Referring to fig. 3, each of the equalizing units 11 includes a first switch Q (Q, or Q), an energy converting circuit T (T, or T), and a second switch QS (QS, or QS), a first side and a second side of the energy converting circuit T (T, or T) are coupled, the first switch Q (Q, or Q) Is connected in series with the first side of the energy converting circuit T (T, or T) and then connected between a positive electrode and a negative electrode of the corresponding cell B (B, or B), the second switch QS (QS, or QS) and the second side of the energy converting circuit T (T, or T) are connected in series, one end of the first switch Q Is connected to a positive electrode of the battery pack 20, the other end of the sampling resistor RS Is connected to a negative electrode 20, the equalizing current Is collected by the sampling resistor RS of the equalizing unit 11 and then transmitted to, the analog front end management module 12 outputs corresponding PWM signals to the first switch Q1(Q2, Q3, Q4, Q5 or Q6) and the second switch QS1(QS2, QS3, QS4, QS5 or QS6) to control the Q1(Q2, Q3, Q4, Q5 or Q6) and the second switch QS1(QS2, QS3, QS4, QS5 or QS6) to be turned on and off, and controls the period of the PWM signals according to the equalizing current Is to make the equalizing current Is constant. The analog front end management module 12 is respectively connected to the first switches Q1 to Q6 through ports e1 to e6, and respectively connected to the second switches QS1 to QS6 through ports n1 to n 6. In the present embodiment, each battery pack 20 has 6 battery cells, and of course, each battery pack 20 may have other numbers of battery cells, for example, 2, 3, 4, 5, 8, and the like, and the number of battery cells in each battery pack 20 may be different, and the specific arrangement thereof is selected by a technician according to actual needs.

The analog front end management module stops outputting the PWM signal PS when the equalizing current Is exceeds a preset threshold value, and resumes outputting the PWM signal PS when the equalizing current Is does not exceed the preset threshold value, so that the equalizing current Is constant.

Referring to fig. 5, the analog front end management module 12 includes a current comparison unit 21 and a PWM signal output interface 22, the analog front end management module 12 outputs a PWM signal PS according to the PWM signal output interface 22, one end of the current comparison unit 21 Is connected to the sampling resistor RS, and the other end Is connected to the PWM signal output interface, and controls the PWM signal output interface 33 to stop outputting the PWM signal PS when the equalizing current Is greater than the preset value until the equalizing current Is less than the preset value. In the present embodiment, the PWM signal output interface 22 is a reset terminal of the PWM latch.

The energy conversion circuit T1-T6 is a flyback transformer.

Referring to fig. 4, the analog front end management module 12 is connected to the cells B1-B6 to collect electrical signals of the cells B1-B6, and generates a corresponding PWM signal PS according to the electrical signals to control on/off of the first switches Q1-Q6 and the second switches QS1-QS6 in the equalization units 11.

Specifically, when any cell B1(B2, B3, B4, B5, or B6) performs active charge equalization, the analog front end management module 12 controls the second switch QS1(QS2, QS3, QS4, QS5, or QS6) and the first switch Q1(Q2, Q3, Q4, Q5, or Q6) of the cell B1(B2, B3, B4, B5, or B6) to be sequentially turned on for a preset time and then turned off, and the Q1(Q2, Q3, Q4, or Q4) and the second switch QS4 (QS 4, or QS 4) are prohibited from being turned on simultaneously; when any cell B1(B2, B3, B4, B5 or B6) performs active discharge equalization, the analog front end management module 12 controls Q1(Q2, Q3, Q4, Q5 or Q6) and a second switch QS1(QS2, QS3, QS4, QS5 or QS6) of cells B1(B2, B3, B4, B5 or B6) to be sequentially turned on for a preset time and then turned off, and Q1(Q2, Q3, Q4 or Q4) and a second switch QS4 (QS 4, QS4 or QS 4) are prohibited from being turned on simultaneously. Of course, the analog front end management module 12 may control multiple groups of battery cells to perform active charge-discharge equalization simultaneously.

More specifically, the analog front end management module 12 controls the second switch QS1(QS2, QS3, QS4, QS5, or QS6) to be opened and the first switch to be closed while controlling the second switch QS1(QS2, QS3, QS4, QS5, or QS6) to be opened when the cell B1(B2, B3, B4, B5, or B6) performs active charge equalization, and the analog front end management module 12 controls the first switch Q1(Q2, Q3, Q4, Q5, or Q6) to be opened and the second switch QS1(QS2, QS3, QS4, QS5, or QS6) to be closed while controlling the cell B1(B2, B3, B4, B5, or B6) to perform active discharge equalization.

The analog front end management module 12 may also control a plurality of battery cells in the battery pack 20 to perform passive equalization, and further control the second switches QS1-QS6 of all the equalization units 11 in the hybrid equalization circuit 10 to be turned off according to the control signal input by the main control module 10, and control one or more equalization units 11 to be turned on according to the electrical signals of the battery cells B1-B6.

Each equalizing unit 11 further includes a current limiting resistor R1(R2, R3, R4, R5, or R6), and the current limiting resistor R1(R2, R3, R4, R5, or R6) is connected in series to a branch where the first side coil of the first switch Q1(Q2, Q3, Q4, Q5, or Q6) and the energy conversion circuit T1(T2, T3, T4, T5, or T6) are located. Specifically, a current limiting resistor R1(R2, R3, R4, R5, or R6) is connected in series between the first switch Q1(Q2, Q3, Q4, Q5, or Q6) and the energy conversion circuit T1(T2, T3, T4, T5, or T6).

Preferably, the hybrid equalizing circuit further includes a fuse F1 and a bidirectional TVS tube ZD1, the fuse F1 is connected in series between the positive electrode of the battery pack 20 and the equalizing units 11, i.e. the fuse F1 is connected in series on the equalizing main loop, and the bidirectional TVS tube ZD1 is connected between the positive electrode of the battery pack 20 and the ground.

Referring to fig. 2, the present invention is described in detail for the active charge equalization process:

when the cell voltage (or SOC) of the cell B1 Is less than a threshold K1 and active charge equalization Is required, the analog front end management module 12 inputs a PWM signal to the second switch QS1 to control the second switch QS2 to be turned on periodically, where the duty ratio of the PWM signal may be adjusted according to a collected current signal Is, for example, 50%. When the second switch QS1 is turned on, a freewheeling circuit "B6 +" → F1 → T1 → QS1 → RS → "B1-", namely, the second side coil of the energy conversion circuit T1 stores B6+ energy, and due to the same-name terminal characteristic of the energy conversion circuit T1, the first switch Q1 is turned off in the reverse direction, and no current flows through R1; when the second switch QS1 is turned off, the energy stored in the second side coil of the energy conversion circuit T1 is transferred to the first side coil of the energy conversion circuit T1, and a free wheeling loop is formed: t1 → "B1 +" → "B1-" → Q1 → R1. Preferably, when the second switch QS1 is closed, the first switch Q1 may be synchronously opened for synchronous rectification, so as to improve the equalization efficiency. The fuse F1 functions to prevent overcurrent, and the current limiting resistor R1 functions to limit current. By analogy, the on-off of a plurality of switch cycles in the second switch can be controlled simultaneously, so that the charging equalization of a plurality of corresponding single batteries is controlled.

When the cell voltage (or SOC) of the cell B3 is higher than a threshold K2, and the difference between the cell voltages (or SOCs) of the other cells is smaller than a threshold K3, and active discharge equalization is required, the analog front end management module 12 inputs a PWM signal to the first switch Q3 to control the first switch Q3 to be turned on periodically, which may be at a specific duty ratio of 50%. When the first switch Q3 is turned on, a freewheeling circuit "B3 +" → T3 → R3 → Q3 → "B3-", namely, the energy conversion circuit T3 first side coil stores B3+ energy, due to the same-name end characteristic of the energy conversion circuit T3, the second switch QS3 is turned off in the reverse direction, and no current flows through the RS; when the first switch Q3 is turned off, the energy stored in the first side coil of the energy conversion circuit T3 is transferred to the second side coil of the energy conversion circuit T3, forming a free-wheeling loop: t3 → F1 → "battery pack of B6+ to B1" → RS → QS 3. Preferably, when the first switch Q3 is closed, the second switch QS1 may be synchronously opened for synchronous rectification, so as to improve the equalization efficiency. The fuse F1 functions to prevent overcurrent, and the current limiting resistor R3 functions to limit current. By analogy, the other single batteries can be controlled to carry out active discharging equalization.

With continued reference to fig. 3, when the passive equalization needs to be turned on, the second switches QS1 to QS6 are in an off state, and the coils of the energy conversion circuits T1 to T6 are in a low on-resistance state; the first switches Q1-Q6 are enabled to conduct as required. If the cell voltages (or SOCs) of the cells B2, B4, and B5 are all higher than the threshold K4 and passive equalization is required, the analog front end management module 12 controls e2, e4, and e5 to output high levels respectively, so that the first switches Q2, Q4, and Q5 are turned on, and the cells B2, B4, and B5 realize simultaneous start of passive equalization. Other channels, and so on, will not be described again.

The analog front end management module 12 generates a PWM signal according to the electrical signal, and transmits the generated PWM signal to the first switch and the second switch in the corresponding equalizing circuit to control the on/off of the first switch and the second switch.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the invention, therefore, the invention is not limited thereto.

Claims

1. The utility model provides a mix equalizer circuit for the equilibrium of a plurality of electric cores in the control group battery, include with a plurality of electric cores correspond a plurality of equalizing unit of being connected, with a plurality of the simulation front end management module that equalizing unit electricity is connected, its characterized in that: the device also comprises sampling resistors, each equalizing unit comprises a first switch, an energy conversion circuit and a second switch, the first side and the second side of the energy conversion circuit are coupled, the first switch is connected in series with the first side of the energy conversion circuit and then connected between the positive pole and the negative pole of the corresponding battery cell, one end of the second switch is connected between the anode of the battery pack and the sampling resistor after being connected with the second side of the energy conversion circuit in series, the other end of the sampling resistor is connected with the cathode of the battery pack, so as to collect the balance current of a plurality of balance units and transmit the balance current to the analog front end management module, the analog front end management module outputs corresponding PWM signals to the first switch and the second switch to control the on-off of the first switch and the second switch, and controlling the period of the PWM signal according to the equalization current feedback so that the equalization current is constant.

2. The hybrid equalizing circuit of claim 1, wherein: and the analog front end management module stops outputting the PWM signal when the equalizing current exceeds a preset threshold value until the equalizing current does not exceed the preset threshold value.

3. The hybrid equalizing circuit of claim 2, wherein: the analog front end management module comprises a current comparison unit and a PWM signal output interface, the analog front end management module outputs the PWM signal according to the PWM signal output interface, one end of the current comparison unit is connected with the equalizing current, the other end of the current comparison unit is connected with the PWM signal output interface, and the PWM signal output interface is controlled to stop outputting the PWM signal when the equalizing current is larger than a preset value until the equalizing current is smaller than the preset value.

4. The hybrid equalizing circuit of claim 1, wherein: the energy conversion circuit is a flyback transformer.

5. The hybrid equalizing circuit of claim 1, wherein: the analog front end management module is connected with the plurality of battery cells to acquire electric signals of the plurality of battery cells, and generates corresponding PWM signals according to the electric signals to control the on-off of the first switches and the second switches in the plurality of equalizing units.

6. The hybrid equalizing circuit of claim 5, wherein: when any one of the battery cells is subjected to active charge equalization, the analog front-end management module controls a second switch and a first switch of the battery cell to be sequentially switched on for a preset time and then switched off, and the first switch and the second switch are forbidden to be switched on simultaneously; when any one of the battery cells is subjected to active discharge equalization, the analog front-end management module controls the first switch and the second switch of the battery cells to be sequentially switched on and switched off after preset time, and the first switch and the second switch are forbidden to be switched on simultaneously.

7. The hybrid equalizing circuit of claim 6, wherein: the simulation front end management module controls the second switch to be switched off and controls the first switch to be switched on when the battery cell performs active charge equalization, and the simulation front end management module controls the first switch to be switched off and controls the second switch to be switched on when the battery cell performs active discharge equalization.

8. The hybrid equalizing circuit of claim 1, wherein: the analog front end management module is connected with the plurality of battery cells to collect electric signals of the battery cells, controls the second switches of all the equalizing units in the hybrid equalizing circuit to be switched off according to external control signals, and controls one or more equalizing units to be switched on according to the electric signals of the battery cells.

9. The hybrid equalizing circuit of claim 1, wherein: each equalizing unit further comprises a current limiting resistor, and the current limiting resistor is connected in series with the first switch and a branch where the first side of the energy conversion circuit is located.

10. The hybrid equalizing circuit of claim 1, wherein: still include fuse and two-way TVS pipe, the fuse concatenates in the positive pole of group battery and a plurality of between the equalizing unit, two-way TVS union coupling in between the positive pole of group battery and ground.

11. A daisy chain communication hybrid equalizing battery equalizing control device is characterized in that: the hybrid equalizing circuit comprises a main control module and a plurality of hybrid equalizing circuits, wherein the hybrid equalizing circuits are connected with the main control module after being sequentially cascaded in a daisy chain communication mode according to the claims 1 to 10, and the main control module manages the hybrid equalizing circuits.