A kind of non-energy consumption type battery charge balancer
The utility model belongs to field of batteries, is a kind of non-energy consumption type battery charge balancer concretely.
In recent years along with electric automobile, high power UPS, the research and development of large-scale power system energy storage device and application, battery industry is flourish.Therefore yet the voltage of single battery and capacity are all extremely limited, and most device has all taked the form of battery pack to use, large-scale energy storage device even thousands of cell connection in series-parallel is arranged together.Because in manufacture process, the voltage of cell, internal resistance etc. are all incomplete same, so the initial capacity of each cell there are differences.The low battery of capacity may occur and cross and put in the battery power discharge process, this moment, other batteries of battery pack can be together in series to its charging, caused the reverse electrode phenomena of this battery; And phenomenon may appear overcharging in the battery that initial capacity is high in charging process, makes whole battery group normally not to be full of.The performance of some cell and life-span all can be affected in the battery pack like this, and then have influence on the operation of whole battery group.Therefore cell is unbalanced is the key factor that influences battery pack work, and it is controlled is very necessary.
Existing equalization methods can be divided into energy consumption type and non-energy consumption type according to the equilibrium of energy loss mode, and the balanced control of energy consumption type is simple and cost is lower, generally uses bypass resistance the battery of overtension is shunted.Patent CN202205861U utilizes devices such as optocoupler to control the switch of bypass resistance, its advantage is simple in structure, maximum shortcoming is not effectively utilized for balanced energy all dissipates by resistance heating, and it can only discharge and battery charge that can not be lower to capacity to the higher battery of capacity.Existing non-energy consumption type equalization methods comprises the electric capacity equilibrium, two-way DC/DC equilibrium, and several different methods such as transformer equilibrium have advantages such as the high battery pack balancing of capacity usage ratio is effective generally, but its control more complicated cost is higher.Patent CN1275829A namely utilizes inductance capacitance to form resonant circuit, make two adjacent at least joint cells carry out equilibrium, its advantage need not be shared signal for equilibrium between each battery and can independently carry out, it is less that shortcoming is mainly balanced number of batteries, though capacity volume variance is little between per two cells, if the series connection of up to a hundred cells is arranged then end to end cell might have bigger difference.Most equalizing circuit all needs cell voltage is measured, and the voltage measurement precision has considerable influence and its to be subjected to the restriction of hardware to portfolio effect, wants to reach therefore that the higher reaction speed of its hardware cost of effect is also relatively slow preferably.Patent CN1667909A has designed a kind of method that does not rely on voltage measurement, has advantages such as favorable expandability simple in structure, and shortcoming is still few with the balancing battery number for the resistance power consumption.
The utility model content
In order to overcome the problem that the resistance heating dissipation does not effectively utilize, the balancing battery number is few that existing non-energy consumption type battery charge balancer exists, a kind of non-energy consumption type battery charge balancer that Battery pack carries out equilibrium and do not need monomer battery voltage is measured is proposed now too much.
For realizing above-mentioned technique effect, the technical solution of the utility model is as follows:
A kind of non-energy consumption type battery charge balancer, comprise the battery pack that a plurality of cells are in series or in parallel to form, it is characterized in that: also comprise balancing battery, switch matrix control module and control system module, voltage acquisition module, current acquisition module and relay, described balancing battery is in parallel with each cell, and formed loop is provided with relay, the switch matrix control module is connected with relay signal, and described control system module links to each other with switch matrix control module signal.
The quantity of described balancing battery is at least one.
Described current acquisition module is connected with battery pack, and the current acquisition module is connected with the control system module.
Described voltage acquisition module is in parallel with battery pack, and voltage acquisition module is connected with the control system module.
Described power supply or load link to each other with cell, are provided with relay between power supply or load and the cell.
Described relay is connected with the control system module by signal.
Advantage of the present utility model is:
1, traditional relatively electric capacity equilibrium, equalization methods such as two-way DC/DC all need carry out equalization operation again after measuring cell voltage.This method is simple to operate, need not voltage is accurately measured, and has reduced SRT, has reduced system cost.
2, the traditional capacitor and inductor equilibrium of contrast, same volume this method euqalizing current is bigger, because balancing battery is the same with cell characteristic in the battery pack, then euqalizing current can reach the 1c short time and more can reach 5c, the ability of equalization is strong, and capacitor electrode sensor etc. will accomplish that big content volume weight is big, and there are shortcomings such as terminal voltage instability in ultracapacitor.
3, with respect to methods such as transformer and two-way DC/DC, software and hardware structure of the present invention is all simple more and efficient is higher, and powerful DC/DC efficient is about 80%.
Description of drawings
Fig. 1 is schematic diagram of the present utility model.
In the accompanying drawing: cell 1, switch matrix control module 2, control system module 3, voltage acquisition module 4, current acquisition module 5, relay 6, power supply or load 7, balancing battery 8.
A kind of non-energy consumption type battery charge balancer, comprise the battery pack that a plurality of cells 1 are in series or in parallel to form, it is characterized in that: also comprise balancing battery 8, switch matrix control module 2 and control system module 3, voltage acquisition module 4, current acquisition module 5 and relay 6, described balancing battery 8 is in parallel with each cell 1, and formed loop is provided with relay 6, switch matrix control module 2 is connected with relay 6 signals, and described control system module 3 links to each other with switch matrix control module 2 signals.The quantity of balancing battery 8 is at least one.Current acquisition module 5 is connected with battery pack, and current acquisition module 5 is connected with control system module 3.Voltage acquisition module 4 is in parallel with battery pack, and voltage acquisition module 4 is connected with control system module 3.Power supply or load 7 link to each other with cell 1, are provided with relay 6 between power supply or load 7 and the cell 1.Relay 6 is connected with control system module 3 signals.
See also Fig. 1, Fig. 1 is schematic diagram of the present utility model.In the present embodiment, cell 1 is many battery pack that series connection forms from #1 to #N, and the corresponding S1 that also comprises is to S2N relay, and each cell 1 both positive and negative polarity connects 2 relays, as MOSFET.For example the #1 anode connects the S1 negative pole and connects S3, and the #2 anode connects the S2 negative pole and connects S5, and these MOSFET and drive circuit thereof are formed switch matrix control module 2 jointly.As shown in Figure 1, when the MOSFET conducting under the cell, this cell is with balancing battery 8 parallel connections.Fuse is connected between switch matrix and balancing battery 8 negative poles, and the protection charging and discharging currents is unlikely to excessive.Voltage detection module is connected the positive and negative two ends of battery pack as shown in Figure 1, i.e. #1 anode and #N battery cathode, and current detection module and relay 6 are connected in the major loop.Control module mainly is made up of single-chip microcomputer and accessory circuit thereof, and single-chip microcomputer regularly gives each battery of switch matrix signal controlling in parallel with balancing battery 8 orders, and the voltage and current value of real-time detection battery pack, if unusually then disconnect S relay 6.
Concrete implementation step is, control module is sent signal by permanent order and frequency, at first other switches of actuating switch S1 and S3 all disconnect and allow #1 cell and balancing battery 8 parallel connections, suppose that #1 cell voltage before in parallel is a, balancing battery 8 voltages are x, in parallel after voltage be half of both sums.Then #1 cell voltage a1 equates with balancing battery 8 voltage x1 after the 1s clock in parallel, i.e. a1=x1=a+x/2.
Cut-off switch S1 and S3, actuating switch S2 and S5, #2 battery and balancing battery 8 are in parallel, and suppose that voltage is b before the parallel connection of #2 battery, and then #2 cell voltage b1 equates with x2 after the 1s in parallel, i.e. b1=x2=b+x1/2.
The back operation is identical with front 2 batteries, namely allows each cell with balancing battery 8 parallel connections respectively.Now calculate the voltage difference of front and back in parallel.#1 and #2 voltage difference are a-b before in parallel, and voltage difference afterwards in parallel is
Suppose a 〉=x 〉=b, a+x-2b≤2a-2b then, (a+x)/4-b/2≤(a-b)/2 then, i.e. a1-b1≤(a-b)/2＜(a-b).
From above-mentioned formula as can be seen, as long as balancing battery 8 voltage x are not less than the minimum voltage among #1 and the #2 battery, so balanced #1 later and #2 cell voltage difference are bound to reduce.Use similar method still can prove after expanding to N battery, as long as voltage is minimum in the not all battery of balancing battery 8 voltages, reduced by the voltage difference between the battery after the balanced cycle so.
The data in real time of current measurement module and voltage measurement module passes to control module simultaneously, if control module is judged battery pack current or magnitude of voltage unusually then disconnect relay 6 that the protection battery pack is activating alarm simultaneously.
If number of batteries is too big, 100 battery series connection are for example arranged, so wherein per 50 batteries are one group, are equipped with a balancing battery 8.Every like this Battery pack can be kept in balance separately, it is variant that but the time has been grown between afterwards possible 2 Battery packs, at this moment just need be with balancing battery 8 parallel connections of two Battery packs once, and then carry out equilibrium separately, can guarantee that like this diversity ratio between 2 Battery packs is less.When carry out parallel operation as for two balancing batteries 8, two kinds of ways are arranged, the 1st, the voltage differences of measurement two Battery packs, difference reaches certain value just carries out, and the 2nd, Fixed Time Interval carries out equalization operation one time.
Control system module 3, voltage acquisition module 4, current acquisition module 5 are the existing module in this area among the application.As long as these modules can be finished the function described in the patent, the physical circuit design can be very inequality.
By above-mentioned character express also by reference to the accompanying drawings as can be seen, behind employing the utility model, can make various large capacity version lithium ion battery cells according to the needs of design, and the production efficiency height, be suitable for large-scale production.Certainly, more than only be concrete exemplary applications of the present utility model, protection range of the present utility model is not constituted any limitation.In addition to the implementation, the utility model can also have other execution mode.All employings are equal to the technical scheme of replacement or equivalent version, all drop within the desired protection range of the utility model.