WO2013174625A1

WO2013174625A1 - Method and apparatus for data transmission via a battery connection

Info

Publication number: WO2013174625A1
Application number: PCT/EP2013/058891
Authority: WO
Inventors: Martin Pohlmann; Jens Strobel; Fabian Henrici
Original assignee: Robert Bosch Gmbh
Priority date: 2012-05-25
Filing date: 2013-04-29
Publication date: 2013-11-28
Also published as: JP2015519021A; JP5951119B2; CN104412612A; DE102012208820B4; DE102012208820A1; KR20150022778A

Abstract

The invention relates to a method (200) for data transmission via a battery connection (104), wherein the data transmission is disturbed by at least one disturbance pulse (400), wherein the method (200) has a step of sending and/or receiving (202) at least one data packet (402) via the battery connection (104), wherein the data packet (402) is sent and/or received with a time offset in relation to the disturbance pulse (400).

Description

Description title

Method and device for data transmission via a battery connection Prior art

The present invention relates to a method for data transmission via a battery connection, to a corresponding device and to an energy store and to a corresponding computer program product.

DE 10 2009 036 086 A1 describes a monitoring electronics for batteries.

Disclosure of the invention

Against this background, the present invention provides a method for data transmission via a battery connection, furthermore a device for data transmission via a battery connection, which uses this method, and an energy store with a corresponding device and finally a corresponding computer program product according to FIGS

Main claims presented. Advantageous embodiments emerge from the respective subclaims and the following description.

Energy and information can be transmitted on an electrical line. In order to receive the information, a sufficient signal strength is required, which makes the information before other oscillations or signals on the electrical conductor or the electrical line recognizable. The invention is based on the recognition that a data block can advantageously be transmitted and / or received within a gap between interfering signals or oscillations.

Sending on a gap allows the data to be sent at a low signal level. In time slots in which no disturbing signals occur on the line, the signal-to-noise ratio is very large, so that a large amount of data can be transmitted over the line in a technically very simple and low-error manner. Communication is possible despite large interference amplitudes. Due to the low signal level results in a reduced

Energy demand. The costs for electronics within the battery cell are lower (ASIC costs) because no high driver power is necessary in the transceiver.

The present invention provides a method for data transmission via a battery terminal, wherein the data transmission of at least one interference pulse is disturbed, the method comprising the following step:

Sending and / or receiving at least one data packet via the

Battery connection, wherein the data packet with a time offset to the

Interference pulse is sent and / or received.

Furthermore, the present invention provides a device for

Data transmission via a battery terminal, which is designed to perform or implement the step of the method according to the invention in at least one corresponding device. Also through this

Embodiment of the invention in the form of a device, the object underlying the invention can be solved quickly and efficiently.

The present invention further provides an energy store with a device according to the approach presented here.

A data transmission can be understood as meaning a communication of two devices, for example a transmitter with a receiver. The transmitter can send a signal and the receiver can receive the signal. Signals can be transmitted in both directions. The signal can cover a distance between the transmitter and the receiver. A battery terminal may be an electrical conductor connected to a pole of a battery. The battery connection can be a DC-carrying line. An interference pulse can, for example, a strong change in level of an electric current flow within a time window on the

Be battery connection. The glitch may include several consecutive level changes or oscillations. The vibrations can be subdued and subside. A data packet may have a predetermined length. The data packet can comprise several blocks. Several

Data packets can be transmitted and / or received consecutively.

A time offset may be a delay that is waited for the glitch until the data packet is sent and / or received. One

Energy storage can be a battery or a battery cell. In the present case, a device can be understood as meaning an electrical device which processes sensor signals and outputs control and / or data signals in dependence thereon. The device may have an interface, which may be formed in hardware and / or software. In the case of a hardware-based embodiment, the interfaces can be part of a so-called system ASIC, for example, which contains a wide variety of functions of the device. However, it is also possible that the interfaces are their own integrated circuits or at least partially consist of discrete components. In a software training, the interfaces may be software modules that are present, for example, on a microcontroller in addition to other software modules.

The skew may be determined using a predetermined threshold of a signal level of the glitch. After a pulse spike of the interference pulse can be waited with the transmission and / or reception until the glitch has subsided below the limit. Thereby, it is possible to transmit with a low transmission power and data packets with a low signal level can be received.

The time offset can be determined depending on a maximum level of the interference pulse. The time offset may be greater when the maximum level is large. The time offset may be smaller when the maximum level is small. As a result, the time offset for the transmission and / or reception can be adapted directly to fluctuating amplitudes of the interference pulses. The length of the time offset can be determined in advance by a trial for a plurality of maximum levels, for example. The time offset to be used can be read, for example, from a table (look-up table). Of the

Time offset can also be determined by a processing rule. The time offset can be immediately following a passage of the

Maximum levels are determined quickly. Information about the time offset can be extracted from the data packet. The time offset can be controlled by a central control unit. For this purpose, the time offset can be transmitted to several users of the method simultaneously. Alternatively, the time offset by means of a

Trigger pulses are triggered on the battery line.

The method may include a step of determining a time duration between the glitch and another glitch, wherein in the step of transmitting and / or receiving the data packet, a time offset not greater than the time duration is used. The further interference pulse can

be a preceding or succeeding glitch. By determining the

For example, the data packet may be sent and / or received in the middle between two glitches.

The method may include a step of affecting a time of occurrence of the noise pulse. Under an influence can one

Triggering or driving to be understood. For example, the

Glitch can be triggered by means of a trigger signal. As a result, for example, a predetermined time for the communication can be kept free.

The time can be synchronized with a frequency reference. A frequency reference can be a system clock. By synchronizing the disturbance cycles, the communication on the battery connection can be optimized. Likewise, the transmission and / or reception can be synchronized to the frequency reference. For example, the interference pulse and the transmission and / or reception can be triggered alternately. An advantage is also a computer program product with program code, which on a machine-readable carrier such as a semiconductor memory, a

Hard disk memory or an optical memory can be stored and for carrying out the method according to one of the above

Embodiments is used when the program product is executed on a computer or a device.

The invention will now be described by way of example with reference to the accompanying drawings. Show it:

1 shows an illustration of a battery with devices for data transmission via a battery connection according to an exemplary embodiment of the present invention;

FIG. 2 is a flowchart of a method for data transfer via a battery terminal that is disturbed by an interfering signal according to an embodiment of the present invention; FIG. Fig. 3 is an illustration of a drive system with a battery according to a

Embodiment of the present invention; and

Fig. 4 is an illustration of glitches with interposed

Data packets transmitted by means of a method for data transmission via a battery connection according to an embodiment of the present invention.

In the following description of preferred embodiments of the present invention are for the in the various figures

represented and similar elements acting the same or similar

Reference numeral used, wherein a repeated description of these elements is omitted.

FIG. 1 shows a representation of a battery 100 with devices 102 for data transmission via a battery connection 104 in accordance with FIG

Embodiment of the present invention. The devices 102 are in This embodiment is arranged within battery cells 106 of the battery 100. In Fig. 1, four series-connected, identically designed battery cells 106 are exemplified within the battery 100. The battery 100 may also include more or fewer battery cells 106. Within the battery cell 106, an electrochemical storage element 108 is arranged.

The memory element 108 has a positive pole and a negative pole, which are led through a sheath of the battery cell 106. Outside the battery cells 106, the poles are connected to the DC line 104. Between the positive pole and the negative pole, the device 102 is connected. The device 102 is configured to transmit data from the battery cell 106 via the line 104. Sensors and data processing devices in the battery cell 106 are not shown. In this exemplary embodiment, the battery 100 has a control unit 110 which has a device 12 which is designed to communicate with the devices 102 via the DC line 104 via a method according to the approach presented here. For example, the controller 1 10 can query a cell state of the individual battery cells 106. The controller 1 10 and the device 1 12 are connected to the DC line 104 for this purpose. In this embodiment, the controller 1 10 is connected between the positive pole and the negative pole of the battery 100. The controller 110 may communicate with other devices external to the battery 100 via battery connector 104. For this purpose, the devices may also have devices according to the approach presented here.

In other words, Fig. 1 shows a battery 100, in which electronic components 102 are configured, synchronous to interference sources on the

Pole terminals, or power connection lines 104, the battery cells 106 to replace (power line communication). The battery 100 can be used as a lithium ion accumulator, for example, as a traction battery 100 for

Electric vehicle (EV) or hybrid electric vehicle (HEV).

The battery 100, in particular as a traction battery of EV / HEV, the

monitored at least during charging and / or discharging, has electronic components 102 configured to synchronize data with sources of interference (loads, particularly an inverter or motor, especially during charge / discharge) via the pole terminals, or power connection lines 104, of the battery cells 106 exchange. In the devices 102 is a Method, which allows this interference-synchronous data transmission within the battery 100 executed.

The synchronization can be done by a master transceiver 110. The master transceiver 110 can advantageously but not necessarily be arranged in the control unit. The synchronization pulse of the master, which serves to synchronize the communication among the nodes, is itself synchronized to the pauses between the noise pulses. In particular, this is advantageous when a TDMA method is used to control the communication in which the communication of the nodes is timed.

Each node can autonomously synchronize its transmission window to the interference pauses. In particular, this is advantageous if a method such as CDMA is used for regulating the communication, in which the communication of the nodes can also take place simultaneously or without central control.

The synchronization can be done at the system level by deriving the clocks for the communication and / or inverter control from a common

Frequency reference.

The synchronization to the sources of interference can be done by a self-learning

Device done. This can preferably be designed as a PLL with upstream filters. As a result, the oscillators of the transceivers are kept synchronous by means of the PLL on the interference pulses (and thus also on the pauses). This can be done centrally in the master 1 10 or separately in each transceiver.

The communication master 110 may assign specific communication slots to the nodes depending on local noise level variations within the battery. Nodes, which are exposed due to their location low noise levels, can basically get less favorable slots in time close to the interference pulse, whereas nodes, which are exposed to high noise levels due to their location, can be assigned the cheap slots in the interference-free window, this can in particular the slots towards the end be the trouble-free time when the disturbances have subsided maximally. 2 shows a flow diagram of a method 200 for transmitting data over a DC-carrying line or a battery terminal that is disturbed by an interfering signal, according to an embodiment of the present invention. The method comprises a step 202 of sending and alternatively or additionally receiving at least one data packet via the line. In step 202, the data packet becomes a time offset to a

Noise pulse of the interfering signal sent and received alternatively or in addition. The interference pulses of the interference signal have regular time intervals. At intervals, a signal level on the line is low. Within the

Distances, the at least one data packet is received and / or sent. The glitches may result from switching within power devices that convert the DC power to AC power

Convert alternating current to direct current.

In other words, FIG. 2 shows a method 200 for the interference-synchronized communication via a power line within a battery. The method 200 enables a disturbance-synchronous data transmission within a battery. In a battery, a (measurement) data transmission between distributed electronic components via dedicated data lines, eg. B. CAN bus done. The battery can also exchange data via Powerline Communication (PLC). The battery can be equipped with an integrated battery sensor

Have data transmission. The communication can be synchronized with system clocks such as an inverter drive.

3 shows a schematic representation of a drive system 300 with a battery 100 according to an embodiment of the present invention. The battery 100 is connected to an inverter 302 via the DC line 104. The inverter 302 is connected to a three-phase motor M via a three-wire line 304. The DC voltage of the battery 100 is converted into a three-phase AC voltage in the inverter 302. The

Three-phase AC voltage is conducted via the three-wire line 304 to the three-phase motor M, where the three-phase AC voltage drives a rotor of the motor M. In order for the inverter 302 to provide the three-phase AC voltage, the DC voltage is generated in a plurality of

Switching operations to three phase-shifted AC voltages converted. The switching processes cause current pulses within the DC line 104. The current pulses have a high amplitude. The battery 100 has at least one device according to the approach presented here for data transmission via the DC line 104. This makes it possible to dispense with a separate data line. By means of a method according to an exemplary embodiment of the present invention, a control unit not depicted here can interrogate status information of the battery 100 via the DC line 104, for example, in order to monitor a charging process of the battery 100 and a discharging process when the motor M is operated. For this purpose, the device uses pauses between the current pulses, while no switching takes place. For example, to take advantage of the pauses, data transmission may be subsequent to a pulse when an amplitude of the pulse is less than a threshold. In addition, a dwell time between the pulse and the data transmission may be inserted to bypass, for example, downstream peaks of the pulse. The switching operations in the inverter 302 can also be combined with the

Data transmission to be coordinated. For example, a block length of the data transmission can be reduced if a repetition frequency of the

Switching operations increases. Conversely, an interval between the

Switching operations have a minimum length to transfer a minimum block length in the break. The switching operations can also be grouped to produce one phase with virtually no pauses while a subsequent phase has longer pauses.

Traction batteries 100 in electric and hybrid vehicles provide inverter 302 and motor (s) M with power. Both generate strong interference, but in particular the inverter 302 due to a clocked operation. Although the actual working frequencies are in the kilohertz range, harmonics occur up to the high megahertz range. These disorders can be one

Disturb communication with the PLC and make it more difficult. Also from one

Battery charger are clocked noise with the same effect in the

Battery 100 impressed. For example, higher transmission power, the interference can be outshined. Also, a multiple transmission until (random) undisturbed reception is possible. Complex codings (redundancy) can also be used for communication. Typical clock frequencies of inverters 302 are in the range between 1 and 100 kHz. In particular, 300 different systems can be used in one system

Frequencies when charging and discharging the battery 100 occur. In particular, 6 and 10 kHz are known for discharging (driving) and 65 kHz for charging.

4 shows a representation of communication between glitches 400 with interleaved data packets 402, which by means of a method for data transmission over a DC line leading in accordance with a

Embodiment of the present invention are transferred. The

Glitches 400 and data packets 402 are shown as columns on a time axis. One size of the columns represents a signal strength, in particular a current on the battery lines. The interference pulses 400 have a significantly greater signal strength than the data packets 402. The

Data packets 402 and the interference pulses 400 have regular intervals, wherein in each case between two interference pulses 400, a data packet 402 is transmitted via the line. The distance 404 between two successive glitches 400 corresponds to a working clock of the inverter and is typically about 100 s at a frequency of 10 kHz. The data packets 402 have the same distance 404 but are offset by a half distance 404 from the interference pulses 400. As a result, the data packets 402 can be transmitted securely despite the small amplitude since the interference pulses 400 do not overlap the data packets. Through the approach presented here is a safe and reliable

Communication via PLC within a battery despite the occurring disturbances possible. An important aspect is the synchronization of the

Transmission of data packets 402 with the sources of interference, so that the

Transmission between the (temporary, regular) noise pulses 400 takes place.

The approach presented here can generally be applied to all batteries which are connected to an inverter or similar pulsed sources of interference. The embodiments described and shown in the figures are chosen only by way of example. Different embodiments may be combined together or in relation to individual features. Also, an embodiment can be supplemented by features of another embodiment.

Furthermore, method steps according to the invention can be repeated as well as carried out in a sequence other than that described.

If an exemplary embodiment comprises a "and / or" link between a first feature and a second feature, then this is to be read so that the embodiment according to one embodiment, both the first feature and the second feature and according to another embodiment either only first feature or only the second feature.

Claims

claims

1 . Method (200) for data transmission via a battery connection (104), wherein the data transmission is disturbed by at least one interference pulse (400), the method (200) comprising the following step:

Transmitting and / or receiving (202) at least one data packet (402) via the battery connection (104), wherein the data packet (402) is connected to a

Time offset is sent to the glitch (400) and / or received.

The method (200) of claim 1, wherein in step (202) of transmitting and / or receiving the time offset using a

predetermined limit value of a signal level of the interference pulse (400) is determined.

3. The method of claim 1, wherein in the step of transmitting and / or receiving, the time offset is determined as a function of a maximum level of the interference pulse.

4. The method according to claim 1, wherein in the step of transmitting and / or receiving, information about the time offset is extracted from the data packet.

5. The method according to claim 1, further comprising a step of determining a time duration between the glitch (400) and another glitch (400), wherein in step (202) sending and / or receiving the data packet (402). a time offset is used which is not greater than the time duration.

6. The method (200) according to one of the preceding claims, comprising a step of influencing a time of occurrence of the interference pulse (400). The method (200) according to claim 6, wherein in the step of influencing the timing is synchronized with a frequency reference.

Device (102) for data transmission via a battery connection (104), which has a device (1 12), which is designed to carry out a method (200) according to one of Claims 1 to 7.

Energy storage (100, 106) with a device (102, 1 10) according to

Claim 8.

Computer program product with program code for carrying out the method according to one of claims 1 to 7, when the program product is executed on a device (102).