CN106602648A - Series battery pack bidirectional lossless balanced improved circuit based on inductor energy storage - Google Patents

Abstract

The invention discloses an improved circuit for two-way non-destructive equalization of a series battery group based on inductive energy storage, wherein the series battery group is divided into left and right parts, the left part of the battery cells is the left battery group, and the right part of the battery cells is Right battery pack. The first and last ends of the series battery pack are between V _CC and GND, and the left and right batteries are connected through the middle equalizing circuit, which is connected to the control circuit. By controlling the on-off of the bidirectional thyristor TRIAC and the energy storage function of the energy storage inductance in the equalization circuit, the circuit can realize the dynamic balance in the charging and discharging process of the battery pack, improve the unbalanced phenomenon of the battery pack in series, and increase the availability of the battery pack. Capacity, reduce the maintenance and replacement cycle of the battery pack in series, and prolong the service life of the battery pack. Therefore, the circuit is suitable for a battery management system of a hybrid electric vehicle, a pure electric vehicle or an energy storage device in an energy storage power station.

Description

An improved circuit for two-way lossless equalization of series battery packs based on inductive energy storage

technical field

The invention relates to the technical field of equalization of battery packs, in particular to an improved circuit for two-way lossless equalization of series battery packs based on inductive energy storage.

Background technique

After multiple charge-discharge cycles of a series battery pack, there are roughly three situations in the distribution of the remaining capacity of each battery cell: the remaining capacity of some battery cells is high; the remaining capacity of some battery cells is low; The remaining capacity of some battery cells is high and the remaining capacity of some battery cells is low.

In view of the above three situations, domestic and foreign scholars have put forward their own solutions. For example, in response to the high remaining capacity of individual battery cells, some researchers have proposed a parallel resistor shunt method, which consumes the energy of the battery module with a high remaining capacity through the resistor by controlling the corresponding switching device. It is wasted in vain, and a large amount of heat is generated during the equalization process, which increases the load of battery thermal management. Some researchers have also proposed equalization circuits such as a bidirectional DC-DC equalization method and a coaxial transformer equalization method. These circuits all use transformers, which increase the cost of the equalization circuit.

At present, according to the energy consumption of the circuit in the equalization process, the equalization control methods of lithium-ion battery packs can be divided into two categories: energy dissipation type and energy non-dissipative type; according to the equalization function classification, it can be divided into charge equalization, discharge Equilibrium and Dynamic Equalization. Charge balance refers to the balance during the charging process. Generally, it starts to balance when the voltage of the battery pack reaches the set value, and prevents overcharging by reducing the charging current; discharge balance refers to the balance during the discharge process. Low-energy battery cells replenish energy to prevent over-discharge; the dynamic equalization method combines the advantages of charge equalization and discharge equalization, and refers to the equalization of the battery pack during the entire charging and discharging process.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned defects in the prior art, and to provide an improved circuit for two-way lossless equalization of series battery packs based on inductive energy storage. The monomers in the battery pack do not appear overcharge and over discharge during the charging and discharging process, improve the unbalanced phenomenon of the battery pack in series, increase the available capacity of the battery pack, reduce the maintenance and replacement cycle of the battery pack in series, and prolong the life of the battery pack service life, reducing the operating costs of hybrid vehicles, electric vehicles and energy storage power stations.

The purpose of the present invention can be achieved by taking the following technical solutions:

An improved circuit based on inductive energy storage for two-way non-destructive equalization of series battery packs. During the charging process, when the energy of any one or more continuous battery cells in the left part of the battery pack is too high (as shown in Figure 1 and Figure 3 ( In a), battery _B11 and battery _B12 are continuous battery cells, and battery _B11 , battery _B12 and battery _B13 are continuous battery cells. That is, in the left part of the battery pack, any continuous one or more A battery cell, the present invention is called a continuous battery, which can be properly regarded as a whole in the equalization process. The definition of the continuous battery on the right part of the battery pack is the same), and one or more continuous energy can be passed The high monomer is regarded as a whole, and the energy balance of this whole is given to the whole composed of the right part of the battery corresponding to this whole, (in Figure 1 and Figure 3 (a), the left part of the battery B _l1 corresponds to the right Part of the battery B _r1 , the whole composed of batteries B _l1 and B _l2 in the left part corresponds to the whole composed of batteries B _r1 and B _r2 in the right part. That is, the whole composed of any continuous one or more battery cells in the left part , corresponding to the whole composed of the right part and the whole in parallel with one or more continuous inductance batteries, the definition of continuous inductance is the same as that of continuous batteries. The definition of the left part of the battery corresponding to the right part is the same ); the balance principle of the right part is the same as that of the left part.

During the discharge process, when one or more consecutive battery cells in the left part of the battery pack are too low in energy, one or more cells with too low energy can be regarded as a whole. When the energy of the right part of the battery corresponding to the low energy whole is not too low, the energy of the right part of the battery corresponding to the low energy whole and any combination of batteries connected to these batteries can be balanced to this Overall low energy. When the energy of the right part of the battery corresponding to the low energy whole is also too low, two steps must be taken to achieve balance. First, the energy of one or more continuous battery cells with high energy in the left part is balanced to the right part. increase the voltage of the battery on the right, and then equalize it by the above-mentioned discharge equalization method. The balance principle of the right part is the same as that of the left part.

The improved circuit for two-way lossless equalization of series battery packs is composed of series battery packs, an equalization circuit and a control circuit. Among them, the battery pack in series is divided into left and right parts, the left part of the battery cells is the left battery pack, and the right part of the battery cells is the right battery pack; when the total number of battery cells is 2n (n is a positive integer), the left and right parts The number of battery cells is n. When the total number of battery cells is 2n+1 (n is a positive integer), the number of cells in the left battery pack is n, and the number of cells in the right battery pack is n+1. The number of cells is n+1, and the number of cells in the right battery pack is n. The present invention takes the number of cells in the left battery pack as n, and the number of cells in the right battery pack as n+1 as an example (the number of cells in the left battery pack is n+1, when the number of cells in the right battery pack is n, the principle is the same); the cells in the left battery pack are named B _l1 , B _l2 , B _l3 , ... B _ln from top to bottom, when the total number of battery cells When it is 2n, the cells of the right battery pack are named B _r1 , B _r2 , B _r3 , ... B _rn from top to bottom. When the total number of cells is 2n+1, the cells of the right battery pack are named from top to bottom They are respectively named B _r0 , B _r1 , B _r2 , B _r3 , ... B _rn ; the positive pole of B _l1 is connected to V _CC , and when the total number of battery cells is 2n, the negative pole of B _r1 is connected to GND. When the total number is 2n+1, the negative pole of B _r0 is connected to GND; the number of batteries is not limited, but as the number of batteries increases, the equalization control will become correspondingly complicated, and the switching frequency of the bidirectional thyristor TRIAC may not meet the requirements. The requirements for energy storage inductors will also increase accordingly, and should be selected according to the actual situation. When the number of batteries is 2n, the number of energy storage inductors L in the equalization circuit is n, which are named L ₁ , L ₂ ... L _n from top to bottom; when the number of batteries is 2n+1, the energy storage inductance L in the equalization circuit The number of energy inductors L is n+1, and they are named L ₀ , L ₁ ... L _n from top to bottom; the two-way thyristor TRIAC with the same number as the inductance is connected in parallel at both ends of the inductance, and the remaining two-way thyristor TRIAC is connected at one end It is connected to one end of the energy storage inductor L, and the other end is connected to one end of the battery, and the control end of the bidirectional thyristor TRIAC is connected to the control circuit, so that the opening and closing of the bidirectional thyristor TRIAC is controlled by the control circuit; when the number of batteries When it is 2n, the number of bidirectional thyristor TRIAC is 3n+2, and the bidirectional thyristor connected in parallel with the inductor is named S ₁ , S ₂ ... S _n from top to bottom, and the bidirectional thyristor connected to the left battery pack The silicon is named S _l1 , S _l2 ... S _l(n+1) from top to bottom, and the bidirectional thyristor connected to the right battery pack is named S _r1 , S _r2 ... S from top to bottom. _r(n+1) ; when the number of batteries is 2n+1, the number of bidirectional thyristor TRIAC is 3n+5, and the bidirectional thyristor connected in parallel with the inductor is named S ₀ , S ₁ ... S respectively from top to bottom _n , the triacs connected to the left battery pack are named S _l0 , S _l1 ... S _l(n+1) from top to bottom, and the triacs connected to the right battery pack are named from top to bottom They are respectively named S _r0 , S _r1 ... S _r(n+1) ; the positive pole of the battery cell B _l1 is connected to V _CC , and the negative pole of the battery cell B _r1 is connected to GND. The control circuit in Figure 1 includes a microcontroller and all triac TRIAC drive circuits. By programming the microcontroller in the control circuit, it analyzes the current battery power and calculates which control strategy should be used to balance the circuit. ;Through the drive circuit in the control circuit, the gate of the bidirectional thyristor TRIAC can be provided with an appropriate driving voltage or off voltage, so that the bidirectional thyristor TRIAC can be turned on or off according to actual needs, so as to achieve the purpose of balancing the battery power .

The working principle of the equalization circuit is as follows:

When the number of batteries is 2n, as shown in Figure 1, during the charging process, if several consecutive batteries in the left battery pack have the highest terminal voltage, the whole composed of these batteries can be discharged and balanced at the same time. Assume that these batteries are B _li , B _l(i+1) ... B _l(i+w) (the number of these batteries is at most equal to all the batteries in the left battery pack, that is, the maximum value of w is n-1, and w is greater than or equal to 0). In order to avoid overcharging B _li , B _l(i+1) ... B _l(i+w) , in a PWM cycle, make the bidirectional thyristor TRIACS _li and S _l(i+w+1) conduction , then the current flows through S _li , energy storage inductance L _i , L _i+1 ... L _i+w , S _l(i+w+1) and B _l(i+w) , B _{l(i+w-1 )} ... B _li , B _li , B _l(i+1) ... B _l(i+w) discharges the energy stored as a whole composed of inductance L _i , L _i+1 ... L _i+w ; and battery B _Li , B _l(i+1) ... B _l(i+w) correspond to B _ri , B _r(i+1) ... B _r(i+w) , S _li and S _{l(i+ w+1)} is turned on for a certain period of time to turn it off, and S _ri and S _r(i+w+1) are turned on at the same time. At this time, the current passes through the inductors L _i , L _i+1 ...L _i+w , S _{r( i+w+1)} , batteries B _r(i+w) , B _r(i+w-1) ...B _ri and S _ri , inductors L _i , L _i+1 ...L _i+w release energy to B _ri , B _r(i+1) ... B _r(i+w) realizes energy transfer from B _li , B _l(i+1) ... B _l(i+w) to B _ri , B _{r( i+1)} ... B _r(i+w) transfer. During the charging process, if several consecutive batteries in the right battery pack have the highest terminal voltage, the equalization principle is the same as that of the left battery pack.

When the number of batteries is 2n, as shown in Figure 1, during the discharge process, if several consecutive batteries in the left battery pack have the lowest terminal voltage, the whole composed of these batteries can be discharged and balanced at the same time. Assume that these batteries are B _li , B _l(i+1) ... B _l(i+w) (the number of these batteries is at most equal to all the batteries in the left battery pack, that is, the maximum value of w is n-1, and w is greater than or equal to 0). Suppose the batteries corresponding to batteries B _li , B _l(i+1) ... B _l(i+w) are B _ri , B _r(i+1) ... B _r(i+w) , when B _ri , When the overall energy composed of B _r(i+1) ...B _r(i+w) is not too low, it can be compared with B _ri , B _r(i+1) ...B _{r(i +w)} A continuous battery as a whole can provide energy for B _li , B _l(i+1) ... B _l(i+w) . Assume that the overall battery is B _r(ip) , B _r(i-p+1) ...B _r(i+q+w) (the maximum value of the sum of p+q+w is n-1, and p is greater than is equal to 0, q is greater than or equal to 0), then S _r(ip) and S _r(i+q+w+1) are enabled, and S _ip , S _i-p+1 ... S _i+q+w+1 are enabled at the same time Remove the S _i , S _i+1 ... S _i+w remaining bidirectional thyristors connected in parallel with the inductor. At this time, the current flows through S _r(ip) , battery B _r(ip) , B _r(i-p+1) ... B _r(i+q+w) , S _r(i+q+w+1) , Inductors L _i , L _i+1 ...L _i+w and S _ip , S _i-p+1 ...S _i+q+w+1 remove S _i , S _i+1 ...S _i+w The triac connected in parallel with the inductance, B _r(ip) , B _r(i-p+1) ... B _r(i+q+w) discharges as inductance L _i , L _i+1 ... L _{i +w} composition of the overall stored energy; S _{r (ip)} and S _{r (i+q+w+1)} and S _ip , S _i-p+1 ... S _i+q+w+1 remove S _i , S _i+1 ...S _i+w The remaining bidirectional thyristors connected in parallel with the inductance are turned on for a period of time and then turned off. At the same time, S _li and S _l(i+w+1) are turned on, and the current flows through the energy storage inductance L _{i +w} , L _i+w-1 ...L _i , S _li , B _li , B _l(i+1) ...B _l(i+w) and S _l(i+w+1) , inductance L _i , L _i+1 ... L _i+w release energy to B _ri , B _r(i+1) ... B _r(i+w) , realizing the energy from B _r(ip) , B _{r(i-p +1)} ... B _r(i+q+w) transfer to B _ri , B _r(i+1) ... B _r(i+w) . When the overall energy composed of B _ri , B _r(i+1) ... B _r(i+w) is too low, the battery in the left battery pack is used to charge the right battery pack as a whole to increase the B _ri , B _{r (i+1)} ……B _r(i+w) energy, and then carry out discharge equalization through the above method. During the discharge process, if several consecutive batteries in the right battery pack have the lowest terminal voltage, the principle of equalization is the same as that of the left battery pack.

When the number of batteries is 2n+1, as shown in FIG. 2 , in the process of charging or discharging, except for the battery B _r0 , the balancing method for other batteries is the same as when the number of batteries is 2n. During the charging process, if the battery B _r0 terminal voltage is the highest, in order to avoid overcharging B _r0 , in a PWM cycle, the bidirectional thyristor TRIACS _r0 and S _r1 are turned on, and the current flows through S _r1 and the energy storage inductor L ₀ , S _r0 and B _r0 are discharged to store energy for the inductor L ₀ . After S _r0 and S _r1 are turned on for a period of time, they are turned off, and S _l0 and S _l2 are turned on at the same time. At this time, the current passes through inductors L ₀ , S _l0 , batteries B _l1 , S _l2 and inductor L ₁ , and inductor L ₀ releases energy to B _l1 , realizing the transfer of energy from B _r0 to B _l1 . During the discharge process, if the terminal voltage of the battery B _r0 is the lowest, in order to avoid over-discharge to B _r0 , in a PWM cycle, the triacs TRIACS _l0 and S _ln are turned on, and the triacs S ₁ , S ln are turned on at the same time S ₂ ... S _n , then the current passes through S _l0 , energy storage inductance L ₀ , S ₁ , S ₂ ... S _n , S _ln and B _ln , B _l(n-1) ... B _l1 , which is the inductance L ₀ to store energy; S _l0 and S _ln are turned on for a period of time to turn them off, and at the same time turn on S _r0 and S _r1 , at this time, the current passes through the inductors L ₀ , S _r1 , battery B _r0 and S _r0 , and the inductor L ₀ releases energy to B _r0 realizes the transfer of energy from B _l1 , B _l2 ... B _ln to B _r0 .

Compared with the prior art, the present invention has the following advantages and effects:

Since the present invention adopts the above-mentioned non-destructive dynamic battery equalization technology in the battery management system of the series battery pack, it can ensure that each battery does not appear overcharge and overdischarge during the charging and discharging process, improve the unbalanced phenomenon of the series battery pack, and improve the efficiency of the battery pack. usable capacity, prolong the service life of battery packs, and reduce the cost of battery energy storage systems in hybrid vehicles, electric vehicles and power stations.

Description of drawings

Fig. 1 is the circuit schematic diagram of the improved circuit of the bidirectional non-destructive equalization of the series battery pack based on inductive energy storage when the number of batteries is 2n;

Fig. 2 is a circuit schematic diagram of an improved circuit of a two-way non-destructive equalization of series battery packs based on inductive energy storage when the number of batteries is 2n+1;

Figure 3(a) is a schematic diagram of the working process of inductive charging when the number of batteries is 2n, taking 4 batteries as an example during the charging process;

Figure 3(b) is a schematic diagram of the working process of inductive discharge during charging when the number of batteries is 2n, taking 4 batteries as an example;

Figure 4(a) is a schematic diagram of the working process of inductive charging when the number of batteries is 2n, taking 4 batteries as an example during the charging process;

Figure 4(b) is a schematic diagram of the working process of inductive discharge during charging when the number of batteries is 2n, taking 4 batteries as an example;

Figure 5(a) is the working principle diagram of inductive charging of battery B _r0 in the charging process when the number of batteries is 2n+1, taking 5 batteries as an example;

Figure 5(b) is the working principle diagram of the inductive discharge of the battery B _r0 during the charging process when the number of batteries is 2n+1, taking 5 batteries as an example;

Figure 6(a) is the working principle diagram of inductive charging of battery B _r0 during the discharge process when the number of batteries is 2n+1, taking 5 batteries as an example;

Figure 6(b) is the working principle diagram of the inductive discharge of the battery B _r0 during the discharge process when the number of batteries is 2n+1, taking 5 batteries as an example;

Figure 7 is the voltage waveform diagram of each battery cell in the equalization circuit charging simulation experiment with 4 batteries as an example;

Figure 8 is a voltage waveform diagram of each battery cell in the equalization circuit discharge simulation experiment of 4 batteries as an example.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Example

Figure 1 is a schematic diagram of the equalization circuit when the number of batteries is 2n. Among them, the battery pack in series is divided into left and right parts, the battery cells in the left part are the left battery pack, and the battery cells in the right part are the right battery pack; the number of battery cells in the left and right parts is n; the cells in the left battery pack are from They are named B _l1 , B _l2 , B _l3 , ... B _ln from top to bottom, and the cells of the right battery pack are named B _r1 , B _r2 , B _r3 , ... B _rn from top to _bottom . The positive pole is connected to V _CC , the negative pole of B _r1 is connected to GND; the number of batteries is not limited, and n is a positive integer greater than or equal to 1, but as the number of batteries increases, the balance control will become complicated accordingly. The switch of the bidirectional thyristor TRIAC The frequency may not meet the requirements, and the requirements for the energy storage inductance will increase accordingly, which should be selected according to the actual situation. The number of energy storage inductors L in the equalization circuit is _n , named L ₁ , L ₂ . One end of the silicon TRIAC is connected to one end of the energy storage inductor L, and the other end is connected to one end of the battery. The control terminals of all the triacs are connected to the control circuit, so that the opening and closing of the triacs are controlled by the control circuit. ; The number of bidirectional thyristors TRIAC is 3n+2, and the bidirectional thyristors connected in parallel with the inductor are respectively named S ₁ , S ₂ ... S _n from top to bottom, and the bidirectional thyristors connected to the left battery pack are composed of They are respectively named S _l1 , S _l2 ... S _l(n+1) from top to bottom, and the triacs connected to the right battery pack are named S _r1 , S _r2 ... S _{r(n +1)} ; the positive electrode of the battery cell B _l1 is connected to V _CC , and the negative electrode of the battery cell B _r1 is connected to GND. The control circuit in the figure includes a microcontroller and all triac TRIAC drive circuits. By programming the microcontroller in the control circuit, it analyzes the current battery power and calculates which control strategy should be used to balance the circuit; through The driving circuit in the control circuit can provide an appropriate driving voltage or shut-off voltage to the gate of the triac TRIAC, so that the bidirectional thyristor TRIAC can be turned on or off according to actual needs, so as to achieve the purpose of balancing the battery power.

Fig. 2 is a schematic diagram of an equalization circuit when the number of batteries is 2n+1. Among them, the series battery group is divided into left and right parts, the left part of the battery cells is the left battery group, and the right part of the battery cells is the right battery group; the number of cells in the left battery group is n, and the number of cells in the right battery group is n +1, the number of cells in the left battery pack can also be n+1, and the number of cells in the right battery pack can be n. The present invention takes the number of cells in the left battery pack as n and the number of cells in the right battery pack as n+1. ; The cells of the left battery pack are named B _l1 , B _l2 , B _l3 , ... B _ln from top to bottom, and the cells of the right battery pack are named B _r0 , B _r1 , B _r2 , B _r3 ,...B _rn , the positive pole of B _l1 is connected to V _CC , the negative pole of B _r0 is connected to GND; there is no limit to the number of batteries, n is a positive integer greater than or equal to 1, but as the number of batteries increases, the balance control will respond accordingly It becomes complicated, the switching frequency of the triac TRIAC may not meet the requirements, and the requirements for the energy storage inductance will also increase accordingly, which should be selected according to the actual situation. The number of energy storage inductors L in the equalization circuit is n+1, which are named L ₀ , L ₁ ... L _n from top to bottom; bidirectional thyristors TRIAC equal in number to the inductance are connected in parallel at both ends of the inductance, and the remaining bidirectional thyristors One end of the thyristor TRIAC is connected to one end of the energy storage inductor L, the other end is connected to one end of the battery, and the control end of the bidirectional thyristor TRIAC is connected to the control circuit, so that the opening and closing of the bidirectional thyristor TRIAC is controlled by the control circuit Control; the number of bidirectional thyristors TRIAC is 3n+5, and the bidirectional thyristors connected in parallel with the inductor are named S ₀ , S ₁ ... S _n respectively from top to bottom, and the bidirectional thyristors connected to the left battery pack are named by They are respectively named S _l0 , S _l1 ... S _l(n+1) from top to bottom, and the triacs connected to the right battery pack are named S _r0 , S _r1 ... S _{r(n +1)} ; the positive electrode of the battery cell B _l1 is connected to V _CC , and the negative electrode of the battery cell B _r1 is connected to GND. The control circuit in the figure includes a microcontroller and all triac TRIAC drive circuits. By programming the microcontroller in the control circuit, it analyzes the current battery power and calculates which control strategy should be used to balance the circuit; through The driving circuit in the control circuit can provide an appropriate driving voltage or shut-off voltage to the gate of the triac TRIAC, so that the bidirectional thyristor TRIAC can be turned on or off according to actual needs, so as to achieve the purpose of balancing the battery power.

Fig. 3(a) is a schematic diagram of the working process of inductive charging when the number of batteries is 2n, taking 4 batteries as an example in the charging process. The total number of battery cells is 4, and the number of battery cells in the left and right parts is 2. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, and the cells of the left battery pack are named B from top to bottom. _r1 , B _r2 , and inductors are named L ₁ and L ₂ respectively from top to bottom. If the terminal voltage of the B _l1 monomer in the left battery pack is the highest among all the monomers, in order to avoid overcharging B ₁ , in a PWM cycle, the bidirectional thyristor TRIACS _l1 and S _l2 are turned on, and the current flows through S _l1 , energy storage inductors L ₁ , S _l2 , and B _l1 , and the discharge of B _l1 stores energy for the inductor L ₁ .

Figure 3(b) is a schematic diagram of the working process of inductive discharge during charging when the number of batteries is 2n, taking 4 batteries as an example. The total number of battery cells is 4, and the number of battery cells in the left and right parts is 2. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, and the cells of the left battery pack are named B from top to bottom. _r1 , B _r2 , and inductors are named L ₁ and L ₂ respectively from top to bottom. As in Figure 3(a), within one PWM period, the energy stored in L ₁ is released to B _r1 . S _l1 and S _l2 are turned on for a certain period of time to turn them off, and S _r1 and S _r2 are turned on at the same time. At this time, the current passes through the inductors L ₁ , S _r2 , batteries B _r1 and S _r1 , and the inductor L ₁ releases energy to B _r1 to realize energy transfer from B _l1 to B _r1 .

Figure 4(a) is a schematic diagram of the working process of inductive charging when the number of batteries is 2n, taking 4 batteries as an example in the charging process. The total number of battery cells is 4, and the number of battery cells in the left and right parts is 2. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, and the cells of the left battery pack are named B from top to bottom. _r1 , B _r2 , and inductors are named L ₁ and L ₂ respectively from top to bottom. If the terminal voltage of the B _l1 cell in the left battery pack is the lowest among all the cells, it is assumed that the energy of the battery B _r1 corresponding to B _l1 will not be too low, and the whole composed of B _r1 and B _r2 can provide energy for B _l1 . In order to avoid over-discharging B ₁ , in one PWM cycle, turn on the bidirectional thyristor TRIACS _r1 and S _r3 , and turn on S ₂ at the same time, then the current flows through S _r3 , S ₂ , energy storage inductors L ₁ , S _r1 and B _r1 and B _r2 , the discharge of B _r1 and B _r2 stores energy for the inductor L ₁ .

Figure 4(b) is a schematic diagram of the working process of inductive discharge during charging when the number of batteries is 2n, taking 4 batteries as an example. The total number of battery cells is 4, and the number of battery cells in the left and right parts is 2. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, and the cells of the left battery pack are named B from top to bottom. _r1 , B _r2 , and inductors are named L ₁ and L ₂ respectively from top to bottom. As in Figure 4(a), in one PWM cycle, S _r1 , S _r3 and S ₂ are turned on for a certain period of time and then turned off, and S _l1 and S _l2 are turned on at the same time. At this time, the current flows through the inductors L ₁ , S _l1 , battery B _l1 and S _l2 , the inductor L ₁ releases energy to B _l1 , realizing the transfer of energy from B _r1 and B _r2 to B _l1 .

Fig. 5(a) is a schematic diagram of the working principle of inductive charging of battery B _r0 in the charging process when the number of batteries is 2n+1, taking 5 batteries as an example. The total number of battery cells is 5, the number of battery cells in the left part is 2, and the number of battery cells in the right part is 3. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, the cells of the right battery pack are named B _r0 , B _r1 , and B _r2 from top to bottom, and the inductors are named L from top to bottom. ₀ , L ₁ , L ₂ , the number of bidirectional thyristor TRIAC is 11, and the bidirectional thyristor connected in parallel with the inductor is named S ₀ , S ₁ , S ₂ respectively from top to bottom, and the bidirectional thyristor connected to the left battery pack The thyristors are named S _l0 , S _l1 , and S _l2 from top to bottom, and the triacs connected to the right battery pack are named S _r0 , S _r1 , and S _r2 from top to bottom. During the charging process, if the battery B _r0 terminal voltage is the highest, in order to avoid overcharging B _r0 , in a PWM cycle, the bidirectional thyristor TRIACS _r0 and S _r1 are turned on, and the current flows through S _r1 and the energy storage inductor L ₀ , S _r0 and B _r0 are discharged to store energy for the inductor L ₀ .

Figure 5(b) is a schematic diagram of the inductive discharge of the battery B _r0 in the charging process when the number of batteries is 2n+1, taking 5 batteries as an example. The total number of battery cells is 5, the number of battery cells in the left part is 2, and the number of battery cells in the right part is 3. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, the cells of the right battery pack are named B _r0 , B _r1 , and B _r2 from top to bottom, and the inductors are named L from top to bottom. ₀ , L ₁ , L ₂ , the number of bidirectional thyristor TRIAC is 11, and the bidirectional thyristor connected in parallel with the inductor is named S ₀ , S ₁ , S ₂ respectively from top to bottom, and the bidirectional thyristor connected to the left battery pack The thyristors are named S _l0 , S _l1 , and S _l2 from top to bottom, and the triacs connected to the right battery pack are named S _r0 , S _r1 , and S _r2 from top to bottom. As in Figure 5(a), in one PWM cycle, S _r0 and S _r1 are turned on for a period of time and then turned off, and S _l0 and S _l2 are turned on at the same time. At this time, the current flows through inductors L ₀ , S _l0 , battery B _l1 , S _l2 and the inductance L ₁ , the inductance L ₀ releases energy to B _l1 , realizing the transfer of energy from B _r0 to B _l1 .

Figure 6(a) is a schematic diagram of the inductive charging of the battery B _r0 during the discharge process when the number of batteries is 2n+1, taking 5 batteries as an example. The total number of battery cells is 5, the number of battery cells in the left part is 2, and the number of battery cells in the right part is 3. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, the cells of the right battery pack are named B _r0 , B _r1 , and B _r2 from top to bottom, and the inductors are named L from top to bottom. ₀ , L ₁ , L ₂ , the number of bidirectional thyristor TRIAC is 11, and the bidirectional thyristor connected in parallel with the inductor is named S ₀ , S ₁ , S ₂ respectively from top to bottom, and the bidirectional thyristor connected to the left battery pack The thyristors are named S _l0 , S _l1 , and S _l2 from top to bottom, and the triacs connected to the right battery pack are named S _r0 , S _r1 , and S _r2 from top to bottom. During the discharge process, if the battery B _r0 terminal voltage is the lowest, in order to avoid over-discharging B _r0 , in a PWM cycle, make the bidirectional thyristor TRIACS _l0 and S _l3 conduction, and open S ₁ and S ₂ at the same time, the current Through S _l0 , inductor L ₀ , S ₁ , S ₂ , S _l3 and batteries B _l2 and B _l1 , energy is stored for inductor L ₀ .

Figure 6(b) is a working principle diagram of the inductive discharge of the battery B _r0 in the discharge process when the number of batteries is 2n+1, taking 5 batteries as an example. The total number of battery cells is 5, the number of battery cells in the left part is 2, and the number of battery cells in the right part is 3. The cells of the left battery pack are named B _l1 and B _l2 from top to bottom, the cells of the right battery pack are named B _r0 , B _r1 , and B _r2 from top to bottom, and the inductors are named L from top to bottom. ₀ , L ₁ , L ₂ , the number of bidirectional thyristor TRIAC is 11, and the bidirectional thyristor connected in parallel with the inductor is named S ₀ , S ₁ , S ₂ respectively from top to bottom, and the bidirectional thyristor connected to the left battery pack The thyristors are named S _l0 , S _l1 , and S _l2 from top to bottom, and the triacs connected to the right battery pack are named S _r0 , S _r1 , and S _r2 from top to bottom. As shown in Figure 6(a), in one PWM cycle, S _l0 , S _l3 , S ₁ and S ₂ are turned on for a period of time and then turned off, and S _r0 and S _r1 are turned on at the same time. At this time, the current flows through the energy storage inductor L ₀ , S _r1 , battery B _r0 and S _r0 are discharged, and the inductor L ₀ releases energy to B _r0 , realizing the transfer of energy from B _l1 and B _l2 to B _r0 .

Figure 7 is a voltage waveform diagram of each battery cell in the equalization circuit charging simulation experiment of 4 batteries as an example. Under the condition of setting a certain control accuracy, each battery cell achieves voltage balance through the equalization circuit.

Figure 8 is a voltage waveform diagram of each battery cell in the equalization circuit discharge simulation experiment of 4 batteries as an example. Under the condition of setting a certain control accuracy, each battery cell achieves voltage balance through the equalization circuit.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (7)

1. a kind of improved circuit of the two-way non-dissipative equalizing of series battery based on inductive energy storage, it is characterised in that the improvement Circuit includes：Series battery, equalizing circuit and control circuit, wherein the series battery includes being divided into left and right two parts, Left half battery cell is left set of cells, and right half battery cell is right set of cells, the left set of cells and the right set of cells It is cascaded, the left set of cells and the right set of cells are coupled together by the middle equalizing circuit, the equilibrium Circuit is connected with the control circuit again, and the control circuit is by controlling bidirectional triode thyristor TRIAC in the equalizing circuit The energy storage of break-make and energy storage inductor act on, realize the dynamic equalization in the series battery charge and discharge process.

2. the improved circuit of the two-way non-dissipative equalizing of a kind of series battery based on inductive energy storage according to claim 1, Characterized in that,

(n is positive integer), the left set of cells and the right battery when in the series battery, battery cell sum is 2n In group, battery cell number is n, when in the series battery, battery cell sum is 2n+1 (n is positive integer), if described Left battery in battery pack number of monomers is n, then the right battery in battery pack number of monomers is n+1, if the left battery in battery pack Number of monomers is n+1, then the right battery in battery pack number of monomers is n.

3. the improved circuit of the two-way non-dissipative equalizing of a kind of series battery based on inductive energy storage according to claim 2, Characterized in that,

When in the series battery, battery cell sum is 2n, the left battery in battery pack monomer is ordered from top to bottom respectively Entitled B_l1、B_l2、B_l3、……B_ln, and B_l1、B_l2、B_l3、……B_lnIt is sequentially connected in series；The right battery in battery pack monomer is from upper B is respectively designated as under_r1、B_r2、B_r3、……B_rn, and B_r1、B_r2、B_r3、……B_rnIt is sequentially connected in series；Wherein, B_l1Positive pole connect V_CC, B_r1Negative pole meet GND；

Energy storage inductor L number in the improved circuit in a balanced way is n, is from top to bottom respectively designated as L₁、L₂……L_n, and L₁、L₂……L_nIt is sequentially connected in series；The quantity of the bidirectional triode thyristor TRIAC in the equalizing circuit is 3n+2, wherein there is n individual two-way Controllable silicon TRIAC is from top to bottom respectively designated as S₁、S₂……S_n, S₁、S₂……S_nIt is sequentially connected in series, and S₁、S₂……S_nRespectively It is connected in parallel on energy storage inductor L₁、L₂……L_nTwo ends；Wherein there is n+1 bidirectional triode thyristor TRIAC to be from top to bottom respectively designated as S_l1、S_l2……S_l(n+1), S_l1、S_l2……S_lnT₁End respectively with energy storage inductor L₁、L₂……L_nUpper end be connected, S_l(n+1)T₁ End and energy storage inductor L_nLower end be connected, S_l1、S_l2……S_lnT₂End and battery cell B_l1、B_l2、B_l3、……B_lnAnode phase Even, S_l(n+1)T₂End and battery cell B_lnNegative terminal be connected；Wherein remaining n+1 bidirectional triode thyristor TRIAC from top to bottom divides S is not named as_r1、S_r2……S_r(n+1), S_r1、S_r2……S_rnT₁End respectively with energy storage inductor L₁、L₂……L_nUpper end be connected, S_r(n+1)T₁End and energy storage inductor L_nLower end be connected, S_r1、S_r2……S_rnT₂End and battery cell B_r1、B_r2、B_r3、……B_rn Negative terminal be connected, S_r(n+1)T₂End and battery cell B_rnAnode be connected；

The gate pole of all bidirectional triode thyristor TRIAC is all connected with the control circuit, makes opening for all bidirectional triode thyristor TRIAC Logical and shut-off is by control circuit control.

4. the improved circuit of the two-way non-dissipative equalizing of a kind of series battery based on inductive energy storage according to claim 2, Characterized in that,

When in the series battery, battery cell sum is 2n+1, the left battery in battery pack number of monomers is n, from up to Under be respectively designated as B_l1、B_l2、B_l3、……B_ln, and B_l1、B_l2、B_l3、……B_lnIt is sequentially connected in series；The right battery in battery pack Number of monomers is n+1, is respectively designated as B from top to bottom_r0、B_r1、B_r2、B_r3、……B_rn, and B_r0、B_r1、B_r2、B_r3、……B_rnAccording to Secondary series connection；Wherein, B_l1Positive pole meet V_CC, B_r0Negative pole meet GND；

Energy storage inductor L number in the improved circuit in a balanced way is n+1, is from top to bottom respectively designated as L₀、L₁……L_n, L₀、L₁、L₂……L_nIt is sequentially connected in series；The quantity of the bidirectional triode thyristor TRIAC in the equalizing circuit is 3n+5, wherein there is n+1 Bidirectional triode thyristor TRIAC is from top to bottom respectively designated as S₀、S₁、S₂……S_n, S₀、S₁、S₂……S_nIt is sequentially connected in series, and S₀、 S₁、S₂……S_nInductance L is connected in parallel on respectively₀、L₁、L₂……L_nTwo ends；Wherein there is n+2 bidirectional triode thyristor TRIAC by up to Under be respectively designated as S_l0、S_l1、S_l2……S_l(n+1), S_l0、S_l1、S_l2……S_lnT₁End respectively with energy storage inductor L₀、L₁、L₂…… L_nUpper end be connected, S_l(n+1)T₁End and energy storage inductor L_nLower end be connected, S_l1、S_l2……S_lnT₂End and battery B_l1、B_l2、 B_l3、……B_lnAnode be connected, S_l0T₂End and battery B_l1Anode be connected, S_l(n+1)T₂End and battery B_lnNegative terminal phase Even；Wherein remaining n+2 bidirectional triode thyristor TRIAC is from top to bottom respectively designated as S_r0、S_r1、S_r2……S_r(n+1), S_r0、S_r1、 S_r2……S_rnT₁End respectively with energy storage inductor L₀、L₁、L₂……L_nUpper end be connected, S_r(n+1)T₁End and energy storage inductor L_n's Lower end is connected, S_r1、S_r2……S_rnT₂End and battery B_r1、B_r2、B_r3、……B_rnNegative terminal be connected, S_r0T₂End and battery B_r1 Negative terminal be connected, S_r(n+1)T₂End and battery B_rnAnode be connected；

The gate pole of all bidirectional triode thyristor TRIAC is all connected with the control circuit, makes opening for all bidirectional triode thyristor TRIAC Logical and shut-off is by control circuit control.

5. changing according to a kind of arbitrary described two-way non-dissipative equalizing of the series battery based on inductive energy storage of Claims 1-4 Good circuit, it is characterised in that

The control circuit includes the drive circuit of microcontroller and all bidirectional triode thyristor TRIAC, by the microcontroller Device is programmed, and is analyzed the electricity of each battery cell in the series battery and is determined the control strategy of the equalizing circuit；Institute The gate pole that drive circuit is stated to bidirectional triode thyristor TRIAC provides appropriate driving voltage or shut-off voltage, allows bidirectional triode thyristor TRIAC is turned on or off according to actual demand.

6. changing according to a kind of arbitrary described two-way non-dissipative equalizing of the series battery based on inductive energy storage of Claims 1-4 Good circuit, it is characterised in that

In the control circuit, the size of the frequency of control signal is according to the inductance value of the circuit energy storage inductor L for being controlled, two-way Depending on the switching loss of controllable silicon TRIAC, battery cell voltage, battery cell capacity.

7. changing according to a kind of arbitrary described two-way non-dissipative equalizing of the series battery based on inductive energy storage of Claims 1-4 Good circuit, it is characterised in that

In the series battery, battery is the secondary cells such as lead-acid battery, lithium ion battery, Ni-MH battery, ultracapacitor.