CN105896663A - Sampling and current-sharing circuit of battery equalization manager - Google Patents

Abstract

The invention provides a sampling and current-sharing circuit of a battery equalization manager. The circuit comprises n sampling and current-sharing units, wherein each sampling and current-sharing unit comprises a sampling circuit and a current-sharing circuit; each sampling circuit comprises a positive electrode sampling and voltage-dividing resistor of a single storage battery and a negative electrode sampling and voltage-dividing resistor of the single storage battery; the ith sampling and current-sharing unit is connected with the ith single battery; one end of the positive electrode sampling and voltage-dividing resistor of the ith single storage battery is connected with a positive electrode Vcelli+ of the ith single battery and the other end is connected with a negative electrode Vcell- of a battery pack; the positive electrode sampling and voltage-dividing resistor of the ith single storage battery comprises two series resistors Ri1 and Ri3; one end of the negative electrode sampling and voltage-dividing resistor of the ith single storage battery is connected with the negative electrode Vcelli- of the ith single battery and the other end is connected with the negative electrode Vcell- of the battery pack; the negative electrode sampling and voltage-dividing resistor of the ith single storage battery comprises two series resistors Ri2 and Ri4; the ith current-sharing circuit is a current-sharing resistor Ri0; and the current-sharing resistor Ri0 is connected between the positive electrode and the negative electrode of the ith single battery in parallel. The sampling and current-sharing circuit of the battery equalization manager has the advantages of being simple in circuit, high in sampling precision, small in leakage current difference, low in cost and the like.

Description

A kind of sampling flow equalizing circuit of battery balanced manager

Technical field

The present invention relates to the sampling flow equalizing circuit of a kind of battery balanced manager, belong to technical field of power management.

Technical background

Circuit of battery pack balancing is used for ensureing that each cell charging voltage equalizes, and makes monomer voltage deviation be maintained at expection In the range of, thus ensure that each cell was not damaged by stress impact during the spacecraft life-span.If not carrying out Equalizaing charge controls, and with the increase of charge and discharge cycles, each monomer battery voltage difference can become larger, and causes its life-span significantly to contract Short.

In current battery balanced management circuit, the sample circuit of battery cell voltage uses electric resistance partial pressure sampling, sees Patent application " the equalizaing charge manager of a kind of Li-ion batteries piles for spacecraft " (201310128544.1) and article " research of spacecraft lithium-ions battery group equalizing circuit ", spacecraft engineering, vol.21, No.1, page 73.This Balancing Manager Average voltage and monomer battery voltage by relatively whole Battery pack realize the Balance route to accumulator.This Balancing Manager The electric resistance partial pressure sample circuit used, also exists the limitation that each battery cell sampling leakage current is inconsistent, adopting on each monomer Sample leakage current is different, and sampling leakage current difference causes cell voltage deviation to increase, and causes monomer voltage unbalanced.

Summary of the invention

The invention aims to solve the problems referred to above, propose a kind of sampling current-sharing being applied to battery balanced manager Circuit, the present invention has that circuit is simple, sampling precision is high, leakage current difference is little, low cost and other advantages.

Realize technical scheme as follows:

The sampling flow equalizing circuit of a kind of battery balanced manager, its set of cells being suitable for has n battery cell, this circuit Including n sampling current-sharing unit, described sampling current-sharing unit includes that sample circuit and flow equalizing circuit, described sample circuit include storing Battery cell positive pole sampling divider resistance and single battery negative pole sampling divider resistance；Ith sample current-sharing unit and i-th Battery cell connects, i=1, and 2 ... n；Wherein

One end of i-th battery cell positive pole sampling divider resistance connects the positive pole Vcelli+ of i-th battery cell, separately One end connects battery electrode Vcell-, and it is by two series resistances R_i1And R_i3Constitute；I-th single battery negative pole is sampled One end of divider resistance connects the negative pole Vcelli-of i-th battery cell, and the other end connects battery electrode Vcell-, its by Two series resistances R_i2And R_i4Constitute；

I-th flow equalizing circuit is flows resistance R_i0, flows resistance R_i0It is parallel between the both positive and negative polarity of i-th battery cell；

R₁₀=0 (i=1)

$R_{20}=\frac{1}{\frac{1}{R_{11}+R_{13}}+\frac{1}{R_{22}+R_{24}}}$

......

$R_{i0}=\frac{1}{R_{11}+R_{13}}+\mathrm{...}+\frac{(i-2)}{R_{(i-1)2}+R_{(i-1)4}}+\frac{(i-2)}{R_{(i-1)1}+R_{(i-1)3}}+\frac{(i-1)}{R_{i2}+R_{i4}}(n\≥i\≥2)$

Described resistance R_i1And R_i3Between lead-out wire as the positive sampled output of i-th battery cell, R_i2And R_i4Between Lead-out wire bears sampled output as i-th battery cell.

Further, sampling current-sharing unit of the present invention also includes modulate circuit, and described modulate circuit is mainly by power supply Protection circuit and output protection circuit；

I-th power protecting circuit includes AD sampling A/D chip, current-limiting resistance R_i7And R_i8, decoupling capacitor C_i1、C_i2、C_i3With C_i4；Described AD sampling A/D chip+vdd terminal two branch roads of connection, a branch road is by resistance R_i8Connect power supply V+, another branch road Pass sequentially through decoupling capacitor C_i3And C_i4Connect Vcell-；-VSS the end of described AD sampling A/D chip connects two branch roads, a branch road By resistance R_i7Connect power supply V-, cross another branch road and pass sequentially through decoupling capacitor C_i1And C_i2Connect Vcell-；AD sampling A/D chip + IN end connects R_i1And R_i3Between lead-out wire ,-IN the end of AD sampling A/D chip connects resistance R_i2And R_i4Between lead-out wire；AD adopts The OUT terminal of sample chip connects output protection circuit；

I-th output protection circuit includes current-limiting resistance R_i9, filter capacitor C_i5And C_i6, catching diode D_i1；Resistance R_i9 One end connects the outfan OUT, resistance R of AD sampling_i9The other end connect diode D respectively_i1Negative pole and electric capacity C_i5, two poles Pipe D_i1Positive pole connect set of cells cold end Vcell-, electric capacity C_i5Series capacitance C_i6, C_i6The other end connects set of cells electronegative potential End Vcell-；Resistance R_i9The other end as the sampled output of battery cell.

Further, sample circuit of the present invention also includes the current-limiting resistance R that samples_i5And R_i6, described R_i5It is connected to R_i1With R_i3Between lead-out wire on, described R_i6It is connected to R_i2And R_i4Between lead-out wire on.

Beneficial effect

First, flows resistance of the present invention is for compensating the sampling leakage current caused by sample circuit, by flows resistance Compensating action makes multiple cell batteries sampling leakage current identical, reduces the impact on cell voltage of the leakage current difference, keeps away The battery cell voltage exempting to cause because of sampling leakage current is unbalanced.

Second, the present invention arranges modulate circuit and includes power protecting circuit and output protection circuit；Power protecting circuit sets Having put current-limiting resistance, decoupling capacitor, decoupling capacitor uses two and is used in series, it is to avoid the impact of single capacitance short-circuit；Output is protected Protection circuit is made up of current-limiting resistance, filter capacitor and catching diode, and filter capacitor takes two to be used in series, it is to avoid single electricity Holding the impact of short circuit, output protection circuit inverse parallel catching diode, when sample circuit fault exports, and catching diode conducting is defeated Going out voltage clamping, protection late-class circuit normally works.

3rd, circuit of the present invention is simple, and sampling precision is high, and circuit reliability is high, low cost.

Accompanying drawing explanation

Fig. 1 is the set of cells sampling flow equalizing circuit structure principle chart of the present invention；

Fig. 2 is that the present invention samples leakage current schematic diagram.

Detailed description of the invention

Below in conjunction with drawings and Examples, the present invention is described in further detail.

The present invention proposes the sampling flow equalizing circuit (as shown in Figure 1) of a kind of battery balanced manager, each battery cell Sampling flow equalizing circuit all includes sample circuit, flow equalizing circuit and modulate circuit.Set of cells has n monomer, set of cells in Fig. 1 Sampling flow equalizing circuit comprises the sampling flow equalizing circuit of battery cell 1 to battery cell n.Wherein, the cold end of set of cells is electricity The cold end Vcell-of pond monomer 1, the hot end of set of cells is the maximum potential end Vcell+ of battery cell n.Below with Illustrate as a example by battery cell n.

Sample circuit includes single battery positive pole sampling divider resistance Rn1 and Rn3, single battery negative pole sampling dividing potential drop Resistance Rn2 and Rn4, sampling current-limiting resistance Rn5 and Rn6, wherein:

One end of resistance Rn1 connects cell hot end Vcell+, after other end series resistance Rn3 of resistance Rn1 It is connected with the electronegative potential Vcell-end of set of cells, i.e. the cold end of first segment monomer；

One end of resistance Rn2 connects cell cold end Vcelln-, after other end series resistance Rn4 of resistance Rn2 It is connected with the electronegative potential Vcell-end of set of cells, i.e. the cold end of first segment monomer；

Lead-out wire between resistance Rn1 and Rn3 is connected with Rn5, and the other end of Rn5 connects the positive pole input of AD sample circuit End；

Lead-out wire between resistance Rn2 and Rn4 is connected with Rn6, and the other end of Rn6 connects the negative pole input of AD sample circuit End.

Flow equalizing circuit is flows resistance Rn0, and flows resistance, for compensating the sampling leakage current caused by sample circuit, passes through The compensating action of flows resistance makes multiple cell batteries sampling leakage current identical, reduces leakage current difference to cell voltage Impact；

One end of flows resistance Rn0 connects the other end of cell hot end Vcell+, resistance Rn0 and connects monomer electricity Pond cold end Vcelln-.

Modulate circuit includes power protecting circuit and output protection circuit.Power protecting circuit is provided with current-limiting resistance Rn7 And Rn8, decoupling capacitor Cn1, Cn2, Cn3, Cn4, decoupling capacitor uses two and is used in series, it is to avoid the shadow of single capacitance short-circuit Ring；Output protection circuit is made up of current-limiting resistance Rn9, filter capacitor Cn5 and Cn6 and catching diode Dn1, and filter capacitor is taked Two are used in series, it is to avoid the impact of single capacitance short-circuit, output protection circuit inverse parallel catching diode, when sample circuit event Barrier output, catching diode conducting output voltage is clamped, and protection late-class circuit normally works, wherein:

One end connection power supply V-of resistance Rn7, other end series capacitance Cn1, other end series capacitance Cn2 of electric capacity Cn1, The other end of Cn2 connects set of cells cold end Vcell-；

Lead-out wire between resistance Rn7 with electric capacity Cn1 is connected with the negative power end-Vss of AD sample circuit；

One end connection power supply V+ of resistance Rn8, other end series capacitance Cn3, other end series capacitance Cn4 of electric capacity Cn3, The other end of Cn4 connects set of cells cold end Vcell-；

Lead-out wire between resistance Rn8 with electric capacity Cn3 is connected with the positive power source terminal+VDD of AD sample circuit；

Resistance Rn9 one end connects the outfan OUT of AD sampling, and the other end of resistance Rn9 connects the negative of diode Dn1 respectively Pole and electric capacity Cn5, the positive pole of diode Dn1 connects set of cells cold end Vcell-, and electric capacity Cn5 series capacitance Cn6, Cn6 is another One end connects set of cells cold end Vcell-.

The accumulator battery of n batteries monomer composition, battery cell 1 sample rate current is maximum, and uncompensation sampling resistor, to monomer 2-monomer n makes sampling leakage current keep consistent with monomer 1 after compensating.Compensation resistance R for monomer 2 sample circuit₂₀To monomer n The compensation resistance R of sample circuit_n0Obtained by following formula:

$R_{i0}=\frac{1}{R_{11}+R_{13}}+\mathrm{...}+\frac{(i-2)}{R_{(i-1)2}+R_{(i-1)4}}+\frac{(i-2)}{R_{(i-1)1}+R_{(i-1)3}}+\frac{(i-1)}{R_{i2}+R_{i4}}(n\≥i\≥2)$

As in figure 2 it is shown, the following design to compensating resistance is briefly described:

If battery cell voltage is V_bat

Section 1 monomer:

Negative terminal sample rate current

Anode sample rate current

Section 2 monomer:

Negative terminal sample rate current

Anode sample rate current

...

N-th joint monomer:

Negative terminal sample rate current

Anode sample rate current

Total sampling leakage current of Section 1 monomer is:

I₁₀=I₁₂+I₂₁+I₂₂+...+I_n1+I_n2

Total sampling leakage current of Section 2 monomer is:

I₂₀=I₂₂+...+I_n1+I_n2

...

Total sampling leakage current of the n-th joint monomer is:

I_n0=I_n2

The sampling leakage current of Section 1 monomer is maximum, uncompensation sampling resistor；2nd to the n-th joint monomer compensates post-sampling electric leakage Stream size is consistent with Section 1, reduces the sampling leakage current difference impact on cell voltage.

The sampling leakage current that Section 2 monomer needs compensate:

I_2b=I₁₀-I₂₀=I₁₂+I₂₁

...

The sampling leakage current that n-th joint monomer needs compensate:

I_nb=I₁₀-I_n0=I₁₂+I₂₁+I₂₂+...+I_n1

Compensating resistance sizes is that monomer voltage removes in the sampling leakage current that need to compensate；

Section 2 monomer compensation resistance:

$R_{20}=\frac{V_{bat}}{I_{2b}}=\frac{V_{bat}}{\frac{V_{bat}}{R_{11}+R_{13}}+\frac{V_{bat}}{R_{22}+R_{24}}}$

...

I-th joint monomer compensation resistance:

$R_{i0}=\frac{V_{bat}}{I_{ib}}=\frac{V_{bat}}{\frac{V_{bat}}{R_{11}+R_{13}}+\frac{V_{bat}}{R_{22}+R_{24}}+\frac{V_{bat}\·2}{R_{21}+R_{23}}+\mathrm{...}+\frac{(i-1)V_{bat}}{R_{i2}+R_{i4}}}=\frac{1}{\frac{1}{R_{11}+R_{13}}+\frac{1}{R_{22}+R_{24}}+\frac{2}{R_{21}+R_{23}}+\mathrm{...}+\frac{(i-1)}{R_{i2}+R_{i4}}}$

In sum, these are only presently preferred embodiments of the present invention, be not intended to limit protection scope of the present invention. All within the spirit and principles in the present invention, any modification, equivalent substitution and improvement etc. made, should be included in the present invention's Within protection domain.

Claims (3)

1. a sampling flow equalizing circuit for battery balanced manager, its set of cells being suitable for has n battery cell, and its feature exists In, this circuit includes n sampling current-sharing unit, and described sampling current-sharing unit includes sample circuit and flow equalizing circuit, described sampling Circuit includes single battery positive pole sampling divider resistance and single battery negative pole sampling divider resistance；Ith sample current-sharing Unit is connected with i-th battery cell, i=1, and 2 ... n；Wherein

One end of i-th battery cell positive pole sampling divider resistance connects the positive pole Vcelli+ of i-th battery cell, the other end Connecting battery electrode Vcell-, it is by two resistance R_i1And R_i3In series；I-th single battery negative pole sampling dividing potential drop One end of resistance connects the negative pole Vcelli-of i-th battery cell, and the other end connects battery electrode Vcell-, and it is by two Resistance R_i2And R_i4In series；

I-th flow equalizing circuit is flows resistance R_i0, flows resistance R_i0It is parallel between the both positive and negative polarity of i-th battery cell；

R₁₀=0

$R_{i0}=\frac{1}{R_{11}+R_{13}}+...+\frac{(i-2)}{R_{(i-1)2}+R_{(i-1)4}}+\frac{(i-2)}{R_{(i-1)1}+R_{(i-1)3}}+\frac{(i-1)}{R_{i2}+R_{i4}},(n\≥i\≥2)$

Described resistance R_i1And R_i3Between lead-out wire as the positive sampled output of i-th battery cell, R_i2And R_i4Between extraction Line bears sampled output as i-th battery cell.

The sampling flow equalizing circuit of a kind of battery balanced manager, it is characterised in that described sampling is equal Stream unit also includes modulate circuit, and described modulate circuit is mainly by power protecting circuit and output protection circuit；

I-th power protecting circuit includes AD sampling A/D chip, current-limiting resistance R_i7And R_i8, decoupling capacitor C_i1、C_i2、C_i3And C_i4；Institute State AD sampling A/D chip+vdd terminal connects two branch roads, branch road is by resistance R_i8Connecting power supply V+, another branch road leads to successively Cross decoupling capacitor C_i3And C_i4Connect Vcell-；-VSS the end of described AD sampling A/D chip connects two branch roads, and a branch road is by electricity Resistance R_i7Connect power supply V-, cross another branch road and pass sequentially through decoupling capacitor C_i1And C_i2Connect Vcell-；+ IN the end of AD sampling A/D chip Connect R_i1And R_i3Between lead-out wire ,-IN the end of AD sampling A/D chip connects resistance R_i2And R_i4Between lead-out wire；AD samples core The OUT terminal of sheet connects output protection circuit；

I-th output protection circuit includes current-limiting resistance R_i9, filter capacitor C_i5And C_i6, catching diode D_i1；Resistance R_i9One end is even Meet the outfan OUT, resistance R of AD sampling_i9The other end connect diode D respectively_i1Negative pole and electric capacity C_i5, diode D_i1's Positive pole connects set of cells cold end Vcell-, electric capacity C_i5Series capacitance C_i6, C_i6The other end connects set of cells cold end Vcell-；Resistance R_i9The other end as the sampled output of battery cell.

The sampling flow equalizing circuit of a kind of battery balanced manager, it is characterised in that described sampling electricity Road also includes the current-limiting resistance R that samples_i5And R_i6, described R_i5It is connected to R_i1And R_i3Between lead-out wire on, described R_i6It is connected to R_i2 And R_i4Between lead-out wire on.