WO2010108758A1

WO2010108758A1 - Circuit assembly for balancing the energy between cells

Info

Publication number: WO2010108758A1
Application number: PCT/EP2010/052550
Authority: WO
Inventors: Markus Heckmann; Felix Franck
Original assignee: Osram Gesellschaft mit beschränkter Haftung
Priority date: 2009-03-27
Filing date: 2010-03-01
Publication date: 2010-09-30
Also published as: DE102009015388A1

Abstract

The invention relates to a circuit assembly for balancing the energy between at least two cells (Z1, Z2, Z3), wherein the at least two cells are connected in series and wherein a converter (601, 602) is provided for every two cells.

Description

Circuit arrangement for energy balance between cells

The invention relates to a compensation unequal

Charges of energy storage or voltage sources, e.g. Battery cells in batteries.

The energy stores are also referred to as cells. The cells are connected to each other in particular in a series connection.

Without access to central node and without a corresponding wiring, the charge states of the individual cells can not be influenced, in particular can not be compensated for each other efficiently, which leads to a significantly reduced cycle stability and to a low usable depth of discharge of the cells. The result is that the series connection of several cells is only as strong as their weakest cell.

FIG. 1 shows a block diagram with two cells 101 and 102 connected in series, wherein energy can be transferred from the cell 101 into the cell 102 on the basis of the circuit shown.

The circuit according to Fig.l has a terminal 109 (positive pole) and a terminal 111 (negative pole) and a center tap 110. The terminal 109 is connected to the cathode of a diode 106, whose anode is connected to the cathode of a diode 105. Parallel to the diode 105, an electronic switch 103 is arranged, which can be activated via a drive unit 104. The node between the diodes 105 and 106 is connected via a series circuit of a resistor 107 and a coil 108 to the center tap 110, wherein the resistor 107 at least one spare series resistor for the entire circuit, in particular for the coil 108 may include. The cell 101 is located between the terminal 111 and the center tap 110, and the cell 102 is located between the center tap 110 and the terminal 109.

This circuit shown in Fig.l has the disadvantages that caused by the diode 106 losses and that only one energy direction is taken into account.

The object of the invention is to avoid the above-mentioned disadvantages and in particular to provide an efficient way to compensate for different states of charge between cells.

This object is achieved according to the features of the independent claims. Further developments of the invention will become apparent from the dependent claims.

To solve the problem, a circuit arrangement for energy balance between at least two cells is specified,

- In which the at least two cells are connected in series with each other;

- In which a converter is provided for every two cells.

By means of the (at least one) transducer, different charge states of the cells can be compensated efficiently. The converter allows a direction independent displacement of electrical energy between the cells. Thus, a state of charge of the weakest cell of the series connection can be compensated automatically from multiple cells and thus the performance of the entire cell array can be significantly increased.

A development is that the cell comprises at least one of the following components:

- An energy store; - an accumulator;

an accumulator cell;

a capacitor;

- a solar cell.

The cell may also be used as a voltage source, e.g. a battery, be configured or at least include such.

In particular, a cell can comprise a parallel connection of several rechargeable batteries, it also being possible to conceive of an interconnection of energy stores (for example rechargeable batteries) as a cell. In particular, a cell may include multiple rechargeable 12V blocks. Parts of the cells may be connected in series and / or in parallel.

In particular, it is possible that the cells have at least partially different voltages and / or capacitances. This could e.g. by asymmetric duty cycles (see more below).

It is expressly noted that the voltages or charges of the individual cells of a chain may not necessarily be the same but also adapted to the cell. In that regard, the voltages or landings of different cells can be quite different from each other. Thus, the approach proposed here makes it possible to balance charges or voltages of individual cells.

Another development is that a capacitor is arranged parallel to the cell.

In particular, it is a further development that the converter is a converter with a boosting functionality and with a low-set functionality, in particular a symmetrical converter. The converter can be an electronic Includes circuit breaker, which is also referred to here as (electronic) switch.

It is also a development that - the transducer has two electronic switches in parallel with the cells, wherein parallel to each switch, a diode is arranged, the cathode is aligned in the direction of the positive pole of the circuit, wherein - parallel to the two switches, a capacitor and / or in a branch in the direction of the outer poles of the cells depending on an inductance in series with the two electronic switches, wherein the inductors are optionally coupled, is arranged or

- Is arranged in a branch in the direction of a center tap of the cells, an inductance.

Furthermore, it is a further development that the electronic switch comprises at least one of the following components:

- an electronic circuit breaker;

a transistor;

- a mosfet;

- an IGBT.

In the context of an additional development, the electronic switches of the converter are alternately controllable for a predetermined period of time, in particular with a duty cycle of (substantially or exactly ever) 50%.

A next development is that the electronic switches are controlled with an asymmetric duty cycle.

In particular, a group of first switches may be activatable for a first time period in a first time interval and a group of second switches may be activated in one second time interval for a second period of time to be activated. Accordingly, the first time period and the second time duration complement each other at a time interval. Accordingly, this approach is possible for any number of m groups of switches. Each of the m groups may have a different number of switches.

An embodiment is that the converter comprises one of the following components: a half-bridge circuit;

- A flyback converter, in particular with an active synchronously operable rectifier;

a Cuk converter, in particular with an active synchronously operable rectifier; a Cuk converter, in particular with coupled inductors and / or an active synchronously operable rectifier.

An alternative embodiment is that a plurality of transducers are provided, wherein at least partially a cell can be driven by a plurality of transducers.

A next embodiment is that a plurality of transducers are arranged partially overlapping and / or encompassing the at least two cells.

It is also an embodiment that the plurality of transducers are controlled alternately.

A development consists in that an energy balance between the at least two cells can be temporarily deactivated.

This makes it possible that temporarily the circuit arrangement is operated in an energy-saving mode, ie that only temporarily (possibly iteratively with specifiable time interval) carried out an energy balance becomes. Accordingly, the energy balance can be activated for a predetermined period of time.

The above object is also achieved by a lighting system comprising

at least one illuminant or at least one lamp, in particular at least one light-emitting diode,

- The circuit arrangement as described herein for supplying the at least one lamp or the at least one lamp with electrical

Energy .

In particular, the cells may be embodied as lead-acid cells, nickel-metal hydride cells, nickel-cadmium cells, lithium-ion cells, lithium polymer cells, lithium iron phosphate cells (LiFePo4) and / or lithium titanate cells. Also, different cell types can be used in combination.

The above object is also achieved by a method for controlling the circuit arrangement described here, comprising a drive unit, by means of which the at least one converter is activated or deactivated.

In particular, the electronic switches of the at least one converter are correspondingly activated by means of the drive unit.

Embodiments of the invention are illustrated and explained below with reference to the drawings.

Show it:

2 shows a circuit arrangement for a possible

Realization of an energy balance between two cells by means of a synchronous half-bridge; 3 shows another circuit example to compensate for

Energy between two cells by means of a synchronous flyback converter;

4 shows a circuit example for balancing the energy between two cells by means of a synchronous Cuk

converter;

5 shows a circuit example for balancing the energy between two cells by means of a synchronous Cuk converter with coupled inductances;

FIG. 6 shows a circuit for balancing the energy between three cells connected in series, wherein a capacitor is arranged parallel to each cell; FIG.

7 shows a circuit for balancing the energy between four series-connected cells, wherein a capacitor is arranged parallel to each cell;

8 shows an alternative circuit for balancing the

Energy between four cells in series;

9 shows a circuit for balancing the energy between six cells connected in series, wherein a capacitor is arranged parallel to each cell;

10 shows an alternative circuit for balancing the energy between six series-connected

cells;

Figure 11 shows another circuit for balancing the energy between six cells connected in series; Figure 12 shows an additional circuit for balancing the energy between six cells connected in series;

13 shows a circuit for balancing the energy between six cells connected in series with an encompassing Cuk converter.

For example, it is proposed to use a synchronously rectifying half-bridge with a choke for a very low-loss charge compensation. Energy is extracted from the stronger cell and transferred to the weaker cell. There is no preferred energy direction here.

Basically, at least one converter (also called a cell converter) can be used for energy balancing between cells, which has both a boosting functionality and a low-set functionality. In particular, a two-quadrant converter can be used. The transducer is preferably symmetrical.

At least one of the following components can be used as converter: a half-bridge;

In particular, the above components can be combined with each other. The cells are connected in series with each other. In this case, any energy store can be used as a cell, for example an accumulator cell or a capacitor. It is also possible that a rechargeable battery with a parallel capacitor is used as a cell.

2 shows a circuit arrangement for a possible realization of the energy balance between two cells 201, 202 by means of a synchronous half-bridge.

The circuit according to FIG. 2 has a terminal 209 (positive pole) and a terminal 211 (negative pole) and a center tap 210. The terminal 209 is connected to the cathode of a diode 206 whose anode is connected to the cathode of a diode 205. Parallel to the diode 205 is an electronic switch 203 and parallel to the diode 206, an electronic switch 212 is arranged. The electronic switches 203 and 212 can be activated via a drive unit 204. The node between the diodes 205 and 206 is connected via a series circuit of a resistor 207 and a coil 208 to the center tap 210, wherein the resistor 207 may comprise at least one equivalent series resistor for the entire circuit, in particular for the coil 208. The cell 201 is located between the port 211 and the center tap 210, and the cell 202 is located between the center tap 210 and the port 209.

It should be noted that the electronic switch may be any controllable switch, e.g. Transistor, Mosfet, IGBT, etc., can act.

3 shows another circuit example for balancing the energy between two cells by means of a synchronous flyback converter. The circuit according to Figure 3 has two cells Zl, Z2, which are connected in series. The positive terminal of the cell Z2 is connected to a terminal Z2p, the negative terminal of the cell Zl is connected to a terminal ZIm, and a center tap between the cells Zl, Z2 is connected to a terminal Zmid.

The terminal Z2p is connected via an inductance L2 to the cathode of a diode D2. The anode of the diode D2 is connected to the terminal Zmid and to the cathode of a diode Dl. The anode of the diode Dl is connected via an inductance Ll to the terminal ZIm. The inductance Ll and the inductance L2 are coupled together. In order to achieve an equalization of the voltages or charges in the connected two cells, the turn ratio in this coupled inductance can be particularly advantageously 1: 1, i. The inductors L 1 and L 2 taken separately are each of the same number of turns and thus (other tolerances, in particular those of the core neglected) have the same inductance value.

Parallel to the diode D2 is an electronic switch S2 and parallel to the diode Dl is provided an electronic switch Sl. Both electronic switches Sl, S2 can be activated (de) by means of a drive unit (not shown).

4 shows a circuit example for balancing the energy between two cells by means of a synchronous Cuk converter.

The circuit according to Figure 4 has two cells Zl, Z2, which are connected in series. The positive terminal of the cell Z2 is connected to a terminal Z2p, the negative terminal of the cell Zl is to a terminal ZIm and a center tap between the cells Z1, Z2 is connected to a terminal Zmid.

Analogously to the synchronous flyback converter described above, the two inductors L 1 and L 2 in each case also have a (substantially) identical inductance value in a particularly advantageous embodiment.

The terminal Z2p is connected via an inductance L2 to the cathode of a diode D2. The anode of the diode D2 is connected to the terminal Zmid and to the cathode of a diode Dl. The anode of the diode Dl is connected via an inductance Ll to the terminal ZIm.

For energy transfer between the two cells Zl and Z2, the capacitor C_cuk, which is typical for a Cuk converter, is connected between the cathode of the diode D2 and the anode of the diode D1. Its value is preferably dimensioned such that the resonance frequency resulting from it and the sum of the two values of the inductances L1 and L2 is clearly below the clock frequency with which the two electronic switches S1 and S2 can be controlled.

In contrast to the value for the capacitor C_cuk off

FIG. 4 shows the value of a capacitor C cuk according to FIG. 5 in such a way that the resonance frequency resulting therefrom and the leakage inductance between the inductances L 1 and L 2 is clearly below the clock frequency with which the two electronic switches S 1 and S 2 can be controlled are. FIG. 5 shows a circuit example for balancing the energy between two cells by means of a synchronous Cuk converter with coupled inductances.

The circuit according to FIG. 5 is based on the circuit shown in FIG. 4, only in FIG. 5 the inductance L 1 and the inductance L 2 are coupled together.

Preferably, the illustrated circuit topologies (half-bridge, flyback converter, coupled Cuk converter)

Inductors, Cuk converters without coupled inductors) with a constant duty cycle. This means that the electronic switches are activated alternately for a predetermined period of time. By way of example, the electronic switches can be mutually active (50% / 50% duty cycle).

It should be noted that other switching ratios are adjustable and in particular a symmetrical or asymmetric duty cycle can be realized.

In particular, with asymmetrically dimensioned cells, an asymmetrical duty cycle can be advantageous.

In all driving methods mentioned so far, the clock frequency already described above by the

Period determined, which elapses between a first and a re-activation of the first electronic switch after exactly one intermediate deactivation. Said clock frequency is in a particularly advantageous embodiment above the human

Hearing threshold and for better compliance with the limits for the radio interference below 5OkHz.

In the "duty-cycle" control method, said period duration is approximately complete of activation phases of the 1st (, 3rd, 5th, ...) electronic switch (with simultaneous deactivation of the 2nd (, 4th, 6th, ...) electronic switch) and activation phases of the 2nd (, 4th, 6th, ...) electronic switch (with simultaneous deactivation of the l. (, 3rd, 5th, ...) electronic switch) filled.

To minimize Umschaltverlusten in the individual electronic switches, it may be advantageous to insert a so-called Umschwingphase between each activation phase in which no one of the existing electronic switch is activated.

As a result, a so-called "Zero Voltage Switching" can be achieved, in which the / the following switch (s) are activated only when the voltage above him / them has swung to zero, which is easily achievable especially for small charge asymmetries. This results in two periods of activation and two Umschwingphasen per period whose total duration, for example, does not exceed 10% of the period.

A "50% -50% duty-cycle" or a "symmetrical duty-cycle" means in particular that both individual activation phases of a period can definitely make up <50% of the period duration, but the two activation phases have the same duration. An "Asymmetric Duty Cycle", on the other hand, indicates activation phases of different lengths.

In all of the embodiments presented here, as well as in all other derivable converter forms, a control method according to the PWM principle is also possible: the above-described transient phases are lengthened, uniform or uneven, and the activation phases are correspondingly shortened.

Finally, regardless of the chosen

Control method, the clock frequency continuously or change abruptly, for example, in the frequency band, which is already mentioned above as advantageous.

In this case, it is advantageous that the charge and / or voltage states of two or even more cells can be compensated with minimal losses. The approach proposed here is scalable for any number of cells. With more than two transducers, the individual transducers or half bridges alternate in the control. Alternatively, one of these may be different

A driving method can be selected, wherein each alternate switch is always activated.

Particularly advantageously, the approach proposed here can be used in battery-operated LED lighting systems, which are supplied with two (or more) lead-acid battery cells.

In the case of a control of the circuit topologies with a constant duty cycle of 50% results in a mean compensation current

j_ 1 U _C eU ₁ - U _C eU ₂

2 R _L + R ^■ , dsON

where R _{L is} an equivalent resistance of the inductor arranged in series and R _dsO N is a residual resistance of an activated electronic switch, eg a MOSFET transistor.

A current ripple can be adjusted by a corresponding choice of inductors. In particular, duty Cyles can be used near 50%. This allows a simplified opposing control of both switches. Alternatively, an independent voltage setpoint can be generated via two resistors and a setpoint / actual value comparison can readjust the duty cycle of the control.

For multicellular systems, a drive for n cells with n setpoints can be derived, which, unlike simple cascading, does not require n-1 half-bridges for n cells, but only n / 2 half-bridges.

Another type of cascading with a total of only n / 2 half-bridges, ie with n switches for n cells, results when a Flyback converter, a Cuk converter or a Cuk converter with coupled inductors is inserted between each directly adjacent half bridges ,

In this case, the energy balance between n> 2 cells with any direction of energy flow is sufficient for the 50% -50% duty cycle. The switches are in this case driven alternately according to a zebra pattern, i. first, the odd-numbered switches S1, S3, S5, ... are active, then the even-numbered switches S2, S4, S6, ...

In this case, each second converter in the form of a switching stage is preferably designed as a half-bridge. In addition, the switches may be shared by the respective adjacent transducers or switching stages, i. Each converter shares one of its switches with the respective converter adjacent to the switch.

Advantageously, a "encompassing" Cuk-converter or a "encompassing" flyback converter can be used, wherein a top AND a low voltage level considered (with a difference of more than two cells) are each occupied by an inductor, if these two inductors with each other coupled and possibly the two (moving) voltage levels across a Cuk Capacitor connected between the top and bottom voltage levels.

6 shows a circuit with three cells Z1, Z2, Z3 connected in series, a capacitor C1, C2, C3 being arranged parallel to each cell.

The series connection of the cells Z1 to Z3 is connected to the terminal Pos (positive pole) and to the terminal Neg (negative pole). The connection between the

Cell Z1 and cell Z2 is referred to as a node K1, and the connection between cell Z2 and cell Z3 is referred to as a node K2.

The terminal Pos is connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2 and D2, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode D1 is via an inductance Ll connected to the port Neg.

Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2 and parallel to the diode D3, an electronic switch S3 is provided.

The anode of the diode D3 is further connected via an inductance L2 to the node K2 and the anode of the diode D2 is connected to the node Kl. Furthermore, a capacitor CkI is provided either parallel to the diodes D1 and D2 (Cuk capacitor) or the inductors L1 and L2 are coupled together. It is also possible that both the capacitor CkI and the coupling between the inductors Ll and L2 are provided.

Thus, FIG. 6 shows a half-bridge 602 comprising the switches S2 and S3 and a cuk-converter 601 with the Switches Sl and S2. If the capacitor CkI is omitted, this is a flyback converter 601. Preferably, the switches S1 and S3 are activated synchronously and the switch S2 is activated when the switches S1 and S3 are inactive.

FIG. 6 enables an energy balance between three cells Z1 to Z3 at four voltage levels.

7 shows a circuit for energy balance between four cells Zl to Z4, wherein a capacitor C 1 to C 4 is arranged parallel to each cell.

The series connection of the cells Z1 to Z4 is connected to the terminal Pos (positive pole) and to the terminal Neg (negative pole). The connection between the cell Z1 and the cell Z2 is called a node K1, the connection between the cell Z2 and the cell Z3 is called a node K2, and the connection between the cell Z3 and Z4 is called a node K3.

The terminal Pos is connected to the cathode of a diode D4, the anode of the diode D4 is connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2 and D2, the anode of the diode D2 is connected to the cathode a diode Dl connected and the anode of the diode Dl is connected to the terminal Neg.

Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2, parallel to the diode D3 is an electronic switch S3 and parallel to the diode D4 is provided an electronic switch S4.

The anode of the diode D4 is further connected via an inductance L2 to the node K3, the anode of the diode D3 is connected to the node K2 and the anode of the diode D2 is connected via an inductance Ll to the node Kl. Furthermore, a capacitor CkI is provided either parallel to the diodes D2 and D3 (Cuk capacitor) or the inductors L1 and L2 are coupled together. It is also possible that both the capacitor CkI and the coupling between the inductors Ll and L2 are provided.

Thus, FIG. 7 shows a half-bridge 701 comprising the switches S1 and S2, a half-bridge 702 comprising the switches S3 and S4 and a cuk-converter 703 with the switches S2 and S3. If the capacitor CkI is omitted, this is a flyback converter 703.

Preferably, the switches Sl and S3 are controlled synchronously and the switches S2 and S4 are then driven synchronously when the switches Sl and S3 are inactive.

8 shows an alternative circuit for energy balance between four cells Z1 to Z4, wherein a capacitor C1 to C4 is arranged parallel to each cell.

The terminal Pos is connected via an inductance L3 to the cathode of a diode D4, the anode of the diode D4 is connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2 and, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode Dl is connected via an inductance Ll to the terminal Neg. Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2, parallel to the diode D3 is an electronic switch S3 and parallel to the diode D4 is provided an electronic switch S4.

The anode of the diode D4 is further connected to the node K3, the anode of the diode D3 is connected via an inductance L2 to the node K2 and the anode of the diode D2 is connected to the node Kl. Furthermore, a capacitor CkI, parallel to the diodes D3 and D4 a capacitor Ck2 and parallel to the diodes Dl to D4, a capacitor Ck3 are optionally provided parallel to the diodes Dl and D2. Optional are the

Inductors Ll, L2 and L3 coupled together.

Thus, FIG. 8 shows a half bridge 801 comprising the switches S2 and S3, as well as a crank converter 802 with the switches S1 and S2 and a crank converter 803 with the switches S3 and S4. Further, a wrap-around Cuk converter 804 is shown with the switches Sl and S4. If the respective Cuk capacitor is omitted, the Cuk converter becomes a flyback converter.

9 shows a circuit for energy balance between six cells Z1 to Z6, wherein a capacitor C 1 to C 6 is arranged parallel to each cell.

The series connection of the cells Z1 to Z6 is connected to the

Connection Pos (positive pole) and connected to the connection Neg (negative pole). The connection between the cell Z1 and the cell Z2 is called a node K1, the connection between the cell Z2 and the cell Z3 is called a node K2, the connection between the cell Z3 and the cell Z4 is called a node K3, the connection between the cell Z4 and the cell Z5 is called a node K4 and the connection between the cell Z5 and the cell Z6 is referred to as a node K5.

The terminal Pos is connected to the cathode of a diode D6, the anode of the diode D6 is connected to the cathode of a diode D5, the anode of the diode D5 is connected to the cathode of a diode D4, the anode of the diode D4 is connected to the cathode of one Diode D3 connected, the anode of the diode D3 is connected to the cathode of a diode D2 and D2, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode Dl is connected to the terminal Neg.

Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2, parallel to the diode D3 is an electronic switch S3, parallel to the diode D4 is an electronic switch S4, parallel to the diode D5 an electronic switch S5 and parallel to the diode D6, an electronic switch S6 is provided.

The anode of the diode D6 is connected via an inductance L3 to the node K5, the anode of the diode D5 is connected to the node K4, the anode of the diode D4 is connected via an inductance L2 to the node K3, which is the anode of the diode D3 connected to the node K2 and the anode of the diode D2 is connected via an inductance Ll to the node Kl.

Furthermore, a parallel to the diodes D4 and D5

Capacitor CkI provided. The inductors L1 and L2 are coupled together.

Thus, FIG. 9 shows a half bridge 901 comprising the switches S1 and S2, a half bridge 902 with the switches S3 and S4 and a half bridge 903 with the switches S5 and S6. Furthermore, FIG. 9 shows a flyback converter 904 the switches S2 and S3 and a Cuk converter 905 with the switches S4 and S5.

10 shows an alternative circuit for energy balance between six cells Z1 to Z6, wherein a capacitor C1 to C6 is arranged parallel to each cell.

The series connection of the cells Z1 to Z6 is connected to the terminal Pos (positive pole) and to the terminal Neg (negative pole). The connection between the cell Z1 and the cell Z2 is called a node K1, the connection between the cell Z2 and the cell Z3 is called a node K2, the connection between the cell Z3 and the cell Z4 is called a node K3, the connection between the cell Z4 and the cell Z5 is referred to as a node K4, and the connection between the cell Z5 and the cell Z6 is referred to as a node K5.

Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2, parallel to the diode D3 is an electronic switch S3, parallel to the diode D4 is an electronic switch S4, parallel to the diode D5 an electronic switch S5 and parallel to the diode D6, an electronic switch S6 is provided. The anode of the diode D6 is connected via an inductance L3 to the node K5, the anode of the diode D5 is connected to the node K4, the anode of the diode D4 is connected via an inductance L2 to the node K3, which is the anode of the diode D3 connected to the node K2 and the anode of the diode D2 is connected via an inductance Ll to the node Kl.

Furthermore, a capacitor CkI and, parallel to the diodes D4 and D5, a capacitor Ck2 are optionally arranged parallel to the diodes D2 and D3. The inductors L1, L2 and L3 are optionally coupled together.

Thus, FIG. 10 shows a half bridge comprising the switches S1 and S2, a half bridge with the switches S3 and S4, and a half bridge with the switches S5 and S6. Furthermore, FIG. 10 shows two encompassing Cuk converters with the switches S2 and S3 or S4 and S5, which can optionally be embodied as flyback converters (without the capacitors CkI and Ck2).

11 shows an alternative circuit for energy balance between six cells Z1 to Z6, wherein a capacitor C1 to C6 is arranged parallel to each cell.

The series connection of the cells Z1 to Z6 is connected to the terminal Pos (positive pole) and to the terminal Neg (negative pole). The connection between cell Z1 and cell Z2 is called a node K1

Connection between the cell Z2 and the cell Z3 is called a node K2, the connection between the cell Z3 and the cell Z4 is called a node K3, the connection between the cell Z4 and the cell Z5 is called a node K4 and the connection between cell Z5 and cell Z6 is referred to as a node K5. The terminal Pos is connected via an inductor L4 to the cathode of a diode D6, the anode of the diode D6 is connected to the cathode of a diode D5, the anode of the diode D5 is connected to the cathode of a diode D4 which is the anode of the diode D4 connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2 and D2, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode D1 is connected via an inductance Ll to the terminal Neg connected.

The anode of the diode D6 is connected to the node K5, the anode of the diode D5 is connected via an inductance L3 to the node K4, the anode of the diode D4 is connected to the node K3, the anode of the diode D3 is connected via an inductance L2 connected to the node K2 and the anode of the diode D2 is connected to the node Kl.

The inductors L2 and L3 are coupled together. A capacitor Ck3 is connected in parallel with the diodes D1 and D2, and a capacitor Ck4 is arranged in parallel with the diodes D5 and D6.

Furthermore, a capacitor CkI and, parallel to the diodes Dl to D6, a capacitor Ck2 are optionally arranged parallel to the diodes D3 and D4. The inductors L1 and L4 are optionally coupled together. Thus, FIG. 11 shows a half bridge comprising the switches S2 and S3, a half bridge with the switches S4 and S5, and a Cuk converter with switches S1 and S2 and a Cuk converter with switches S5 and S6. Furthermore, a flyback converter with the switches S3 and S4 is present.

On the basis of the optional capacitor Ck2 can be a encompassing Cuk-converter or on the basis of the connection of the inductors Ll and L4, a encompassing flyback converter (without capacitor Ck2) can be realized.

12 shows an alternative circuit for energy balance between six cells Z1 to Z6, wherein a capacitor C1 to C6 is arranged parallel to each cell.

Connection between the cell Z2 and the cell Z3 is called a node K2, the connection between the cell Z3 and the cell Z4 is called a node K3, the connection between the cell Z4 and the cell Z5 is called a node K4 and the connection between cell Z5 and cell Z6 is referred to as a node K5.

The terminal Pos is connected via an inductor L4 to the cathode of a diode D6, the anode of the diode D6 is connected to the cathode of a diode D5, the anode of the diode D5 is connected to the cathode of a diode D4 which is the anode of the diode D4 connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode Dl is connected via an inductance Ll to the terminal Neg connected . Parallel to the diode Dl is an electronic switch Sl, parallel to the diode D2 is an electronic switch S2, parallel to the diode D3 is an electronic switch S3, parallel to the diode D4 is an electronic switch S4, parallel to the diode D5 an electronic switch S5 and parallel to the diode D6, an electronic switch S6 is provided.

The inductors L1 and L2 are coupled together, and the inductors L3 and L4 are coupled together. Parallel to the diodes D3 and D4, a capacitor CkI is arranged.

Thus, FIG. 12 shows a half bridge comprising the switches S2 and S3, a half bridge with the switches S4 and S5, and a Cuk converter with the switches S3 and S4, a flyback converter with the switches S1 and S2, and a flyback converter the switches S5 and S6.

FIG. 13 shows an alternative circuit for balancing energy between six cells Z1 to Z6, wherein a capacitor C1 to C6 is arranged parallel to each cell.

The series connection of the cells Z1 to Z6 is connected to the terminal Pos (positive pole) and to the terminal Neg (negative pole). The connection between the cell Z1 and the cell Z2 is called a node K1, the connection between the cell Z2 and the cell Z3 is called a node K2, the connection between the cell Z3 and the cell Z4 is considered a node K3, the connection between the cell Z4 and the cell Z5 becomes a node K4, and the connection between the cell Z5 and the cell Z6 is called a node K5 denotes.

The terminal Pos is connected via an inductor L4 to the cathode of a diode D6, the anode of the diode D6 is connected to the cathode of a diode D5, the anode of the diode D5 is connected to the cathode of a diode D4 which is the anode of the diode D4 connected to the cathode of a diode D3, the anode of the diode D3 is connected to the cathode of a diode D2, the anode of the diode D2 is connected to the cathode of a diode Dl and the anode of the diode Dl is connected via an inductance Ll to the terminal Neg connected .

The inductors L1 and L2 are coupled together, and the inductors L3 and L4 are coupled together. Parallel to the diodes Dl to D6, a capacitor CkI is arranged. 13 shows a half-bridge comprising the switches S2 and S3, a half-bridge with the switches S4 and S5 and a encompassing Cuk converter with the switches S1 and S6, a flyback converter with the switches S1 and S2 and a flyback converter with the switches S5 and S6.

In the example according to FIG. 13, the cells Z1 and Z6 are balanced by means of the encompassing Cuk converter, the transfer of the voltages takes place via the two independent flyback converters to the two half bridges. Thus, the two internal switches S3 and S4 are only used by one converter. If the edges are occupied by inductances and at the same time all inductances involved in the energy balance are coupled in the same direction in the same direction, this encompassing topology results.

A common sense coupling of the inductors is an advantageous embodiment for a number of more than four cells (n> 4).

The coupling of the inductors is optional.

The compensation circuit does not have to be operated permanently. For example, it is possible to save energy by providing hystereses to enable energy balance only when exceeding a predetermined threshold (e.g., imbalance).

Claims

claims

1. Circuit arrangement for energy balance between at least two cells,

- In which the at least two cells are connected in series with each other;

- In which a converter is provided for every two cells.

2. Circuit arrangement according to claim 1, wherein the cell comprises at least one of the following components: - An energy store;

- an accumulator;

an accumulator cell;

a capacitor;

- a solar cell.

3. Circuit arrangement according to one of the preceding claims, in which a capacitor is arranged parallel to the cell.

4. Circuit arrangement according to one of the preceding claims, wherein the converter comprises a converter with a Hochsetzfunktionalität and with a

Tiefsetzfunktionalität, in particular a symmetric converter is.

5. Circuit arrangement according to one of the preceding claims, - in which the transducer comprises two electronic switches parallel to the cells, wherein parallel to each switch, a diode is arranged, the cathode is aligned in the direction of the positive pole of the circuit, - in the parallel to the two switches

Capacitor and / or in a branch in the direction of the outer poles of the cells each have an inductance in series with the two electronic switches, wherein the Inductors are optionally coupled, arranged or

- Is arranged in which a branch in the direction of a center tap of the cells, an inductance.

6. Circuit arrangement according to claim 5, wherein the electronic switch comprises at least one of the following components:

- an electronic circuit breaker; a transistor;

- a mosfet;

- an IGBT.

7. Circuit arrangement according to one of claims 5 or 6, wherein the electronic switches of the converter are alternately for a predetermined period of time, in particular with a duty cycle of substantially 50%, can be controlled.

8. Circuit arrangement according to one of claims 5 to 7, wherein the electronic switch can be controlled with an asymmetric duty cycle.

9. Circuit arrangement according to one of the preceding claims, wherein the converter comprises one of the following components:

A half-bridge circuit; - A flyback converter, in particular with an active synchronously operable rectifier;

a Cuk converter, in particular with an active synchronously operable rectifier;

a Cuk converter, in particular with coupled inductors and / or an active synchronously operable rectifier.

10. Circuit arrangement according to one of the preceding claims, in which a plurality of transducers are provided, wherein at least partially a cell can be driven by a plurality of transducers.

11. Circuit arrangement according to one of the preceding claims, wherein a plurality of transducers are arranged partially overlapping and / or encompassing for the at least two cells.

12. Circuit arrangement according to claim 11, wherein the plurality of transducers are alternately controllable.

13. Circuit arrangement according to one of the preceding claims, wherein an energy balance between the at least two cells is temporarily deactivated.

14. Light system comprising

- At least one lamp or at least one lamp, in particular at least one light emitting diode, - The circuit arrangement according to one of the preceding claims for supplying the at least one lamp or the at least one lamp with electrical energy.

15. A method for driving the circuit arrangement according to one of claims 1 to 13, comprising a

Control unit, by means of which the converter is activated or deactivated.