System for determining impedance values of an electrochemical energy source in a means of transportation, and method therefor

Abstract

The present invention relates to an electrical system (100) and a method for determining impedance values of an electrochemical energy source (13) of an electrically driven means of transportation (10) by means of electrochemical impedance spectroscopy (EIS). The electrical system (100) comprises, inter alia, power electronics (11, 12) having: an EIS actuator portion for impressing measurement pulses of the EIS onto electrical power for the means of transportation (10) by means of the power electronics (11, 12) in accordance with the outputted commands of an EIS unit (15); a conversion portion for the power conversion of the power electronics (11, 12); and a superposing portion for superposing converted electrical power with the impressed measurement pulses of the EIS before output to an electrical connection to the electrochemical energy source (13).

Description

[0001] System for determining impedance values ​​of an electrochemical energy source in a means of transport and method therefor

[0002] The present invention relates to an electrical system for determining impedance values ​​of an electrochemical energy source in an electrically driven means of transport by means of electrochemical impedance spectroscopy (EIS), as well as a method for determining impedance values ​​of an electrochemical energy source in an electrically driven means of transport by means of EIS.

[0003] It is known to use a measurement technique known as electrochemical impedance spectroscopy to image various electrochemical phenomena inside a fuel cell or battery. These phenomena, through detailed analysis, can reveal the state of aging, the state of charge, and other parameters. Such measurable phenomena, as indicated in Figures 11 and 12 for known methods, allow conclusions to be drawn about the properties of the fuel cell or battery by assigning frequency ranges of measured impedance values ​​to sections of an equivalent circuit diagram of the fuel cell or battery.Such phenomena include, for example, humidity measurement and aging mechanisms of a fuel cell such as peroxide formation, platinum oxide formation, platinum deposition, membrane damage, area reduction of an active material, as well as aging and charge-specific phenomena of a battery, such as ohmic resistance of an electrolyte or diffusion processes of active materials for charge mobility.

[0004] To date, such measurement techniques have been the subject of laboratory tests in the context of product development on a test bench, or at least using dedicated measurement technology on a complete vehicle that is not intended for use by a user at the time of measurement.

[0005] Accordingly, there is a need for increased flexibility and expanded application of electrochemical impedance spectroscopy (EIS) measurement technology on vehicles or other means of transport powered by a fuel cell or battery. The object of the invention is to create a technology that enables a reduction in the effort and cost of equipping a means of transport with EIS measurement technology.

[0006] The above object is achieved by an electrical system having the features of claim 1 and by a method having the steps of claim 27. Further features and details of the invention emerge from the subclaims, the description and the drawings.

[0007] Features and details that are described in connection with the system according to the invention naturally also apply in connection with the method according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is or can always be made to each other.

[0008] The electrical system according to the invention serves to determine impedance values ​​of an electrochemical energy source of an electrically powered means of transport by means of electrochemical impedance spectroscopy (EIS).

[0009] The electrical system comprises an on-board section of the electrical system, which is arranged on board the means of transport and is electrically connected to the electrochemical energy source, with power electronics for converting the electrical power provided by the electrochemical energy source in the on-board section. Additionally or alternatively, the electrical system comprises a charging structure section, which is arranged in a charging device and is electrically connectable to the electrochemical energy source of the means of transport via a temporarily established charging connection, with power electronics for converting the supply power provided by an external supply network in the charging structure section.In addition, the electrical system includes sensors for recording parameters of electrical operating states of the electrochemical energy source and an EIS unit for determining impedance values ​​of the electrochemical energy source using EIS.

[0010] The EIS unit is arranged in the on-board section and communicatively connected to the power electronics and the sensors. Alternatively, the EIS unit is arranged in the load structure section and communicatively connected to the power electronics and connectable to the sensors via a temporarily established communication link. The EIS unit comprises a pulse command section for issuing commands for measurement pulses that are impressed on the electrochemical energy source for an EIS. The EIS unit also comprises a measurement reception section for receiving measurements of impulse responses that result from an impedance of the electrochemical energy source and in response to the measurement pulses of the EIS in the on-board section, and that are detected by the sensors. Likewise, the EIS unit comprises a determination section for determining impedance values ​​of the electrochemical energy source from the received measurements of the impulse responses.

[0011] The power electronics comprise an EIS actuator section for applying the EIS measurement pulses, in accordance with the commands issued by the EIS unit, to a converted electrical power for the means of transport using the power electronics. The power electronics also comprise a conversion section for the power conversion of the power electronics. The power electronics also comprise a superposition section for superimposing the converted electrical power with the applied EIS measurement pulses before delivery to an electrical connection with the electrochemical energy source.

[0012] Likewise, the method according to the invention serves to determine impedance values ​​of an electrochemical energy source of an electrically powered means of transport using electrochemical impedance spectroscopy (EIS). The method can be carried out, for example, by the aforementioned electrical system according to the invention, although implementation is not limited thereto. The method comprises the following steps, either overlapping or simultaneously:

[0013] - issuing commands for measuring pulses of an EIS to be applied to an electrical power for the means of transport;

[0014] - Impressing the measurement pulses of the EIS on an electrical power in accordance with the commands issued in step by means of power electronics; - Receiving measurements of impulse responses resulting from an impedance of the electrochemical energy source and in response to the measurement pulses of the EIS in the on-board section, which are detected by means of sensors; and

[0015] - Determining impedance values ​​of the electrochemical energy source from the received impulse response measurements; as well as the intermediate steps:

[0016] - converting electrical power provided by the electrochemical energy source for the means of transport, or converting supply power provided by an external supply network to charge the electrochemical energy source of the means of transport; and

[0017] - Superimposing a converted electrical power with the impressed measuring pulses of the EIS before delivery to an electrical connection with the electrochemical energy source.

[0018] The invention thus provides for the first time for performing EIS measurements using existing power electronics on board a means of transport or in a charging infrastructure for the same, without requiring dedicated measurement technology, in particular an actuator for introducing measurement pulses at different frequencies to a fuel cell or a battery. The invention also provides for the first time for performing the measurement during a dedicated operating function of the existing power electronics, such as a drive supply or charging supply, i.e., in particular, superimposed on a power conversion of the power electronics for its dedicated operating function, without disrupting or suspending an operating sequence, or without waiting for a rest period between operating sequences.

[0019] A major advantage of the invention is that an EIS measurement can be implemented on a fuel cell or battery of a vehicle without dedicated measurement technology in the form of an additional sensor, transistor, or actuator for introducing measurement pulses and sensors into the electrical system of the vehicle and, if applicable, the charging infrastructure. This eliminates the manufacturing costs and assembly effort required to equip the electrical system with additional measurement technology. Another advantage is that existing vehicle systems can be retrofitted without additional hardware by implementing the EIS unit in software on an on-board computer with a connection to sensor signals and control connections.

[0020] Another major advantage is that the EIS measurement can be carried out at any time or for any length of time, as well as continuously, periodically, sporadically or permanently, since the necessary hardware is available for the EIS measurement at any time and even beyond the dedicated operational processes.

[0021] This also has the advantage of saving time when carrying out an EIS measurement during an operational process, as the measurements do not necessarily have to be carried out during a standby state in which both the means of transport and the charging infrastructure are out of operation, which is only rarely or to a limited extent the case in commercial usage profiles, for example.

[0022] As a further advantage of the invention, based on flexible and continuous data collection in the implementation of the invention, monitoring of a development of a state of a fuel cell or battery over periods of time or a life cycle of the same or the means of transport is made possible.

[0023] As a further advantage, due to the large amount of data collected by users when implementing the invention on the end products in the form of transport means or loading structures, a very large collection of analyzable data is technically possible, which can be used for various purposes, such as product improvement.

[0024] According to one aspect of the invention, the electrochemical energy source on board the means of transport may be a fuel cell device.

[0025] According to an alternative aspect of the invention, the electrochemical energy source on board the means of transport may be a traction battery device.

[0026] According to one aspect of the invention, the EIS unit may further comprise an analysis section for analyzing a state of aging (SOH) of the electrochemical energy source from the determined impedance values ​​at different frequencies of the measurement pulses. According to one aspect of the invention, the EIS unit may further comprise an analysis section for analyzing a state of charge of the drive battery device from the determined impedance values ​​at different frequencies of the measurement pulses.

[0027] According to one aspect of the invention, the power electronics of the on-board section can comprise a drive inverter for controlling the power of at least one drive motor of the means of transport, which interacts with the EIS actuator section. The drive inverter preferably already has suitable hardware, such as a power transistor, which is suitable for implementing the invention and is already conventionally present in vehicles and can be used for implementing the invention.

[0028] According to an alternative aspect of the invention, the power electronics of the on-board section can comprise a DC-DC converter for supplying power to an auxiliary unit, an actuator, and / or on-board electronics of the means of transport, which interacts with the EIS actuator section. This hardware is also already conventionally present in vehicles and can be used to implement the invention.

[0029] According to an alternative aspect of the invention, the power electronics of the on-board section can comprise a charging voltage converter for charging the drive battery device on board the means of transport, which cooperates with the EIS actuator section. This hardware is also already conventionally present in vehicles and can be used to implement the invention, whereby a direct connection to the drive battery device can be used.

[0030] According to one aspect of the invention, the power electronics of the charging structure section can comprise a supply voltage converter for providing charging power for the electrically connectable means of transport, which cooperates with the EIS actuator section. This hardware is also conventionally already present in a charging infrastructure and can be used to implement the invention.

[0031] According to one aspect of the invention, the power conversion of the power electronics, which is superimposed with the measurement pulses from the EIS actuator section, can comprise a modulation between an output voltage from the electrochemical energy source and a multi-phase three-phase current for driving the at least one drive motor, or different modulations for driving different drive motors.

[0032] According to one aspect of the invention, the power conversion of the power electronics, which is superimposed with the measurement pulses from the EIS actuator section, can comprise a modulation between a multi-phase three-phase current and an input voltage into the electrochemical energy source for regeneration by one of the at least one drive motor, or a modulation for regeneration by one drive motor and a modulation for driving another of the at least one drive motor.

[0033] According to one aspect of the invention, the power conversion of the power electronics, which is superimposed with the measuring pulses from the EIS actuator section, can comprise a voltage conversion between an output voltage of the electrochemical energy source and a supply voltage for the auxiliary unit, the actuator and / or the on-board electronics of the means of transport.

[0034] According to one aspect of the invention, the power conversion of the power electronics, which is superimposed with the measurement pulses from the EIS actuator section, can comprise a voltage conversion between a charging voltage provided by the charging structure section of the electrical system for the electrically connectable means of transport and a charging voltage with which the drive battery device is charged in the on-board section of the electrical system.

[0035] According to one aspect of the invention, the power conversion of the power electronics, which is superimposed with the measurement pulses from the EIS actuator section, can comprise a power conversion between a supply power provided from an external supply network and a charging power provided by the charging structure section of the electrical system for the means of transport.

[0036] According to one aspect of the invention, the means of transport can have a control unit for controlling operating functions of the means of transport, which is communicatively connected to the power electronics and the sensors in the on-board section. The EIS unit of the electrical system can be integrated into the control unit. Thus, existing hardware can again be used to implement the invention.

[0037] According to one aspect of the invention, the means of transport can have a battery management system (BMS) for monitoring operating states of the drive battery device, which is communicatively connected to the power electronics and sensors in the on-board section. The EIS unit of the electrical system can be integrated into the BMS. Thus, existing hardware can again be used to implement the invention.

[0038] According to one aspect of the invention, the EIS unit in the charging structure section can be communicatively connected to the power electronics and integrated into the charging device. Thus, existing hardware can be used to implement the invention.

[0039] According to one aspect of the invention, the sensors for detecting parameters of electrical operating states may comprise a current sensor and a voltage sensor for measuring impedance in electrical connections to or at power outputs of the electrochemical energy source.

[0040] According to one aspect of the invention, the electrical system can comprise at least one sensor for detecting parameters of dynamic movement operating states of the means of transport, preferably a speed sensor communicatively connected to the EIS unit. Thus, interactions between the EIS measurement and the movement or conditions between them can be monitored.

[0041] According to one aspect of the invention, the electrical system may comprise a torque sensor, a rotation angle sensor, a speed sensor, and / or an acceleration sensor communicatively connected to the EIS unit, wherein the EIS unit comprises a measurement pulse limiting section for limiting the intensity of the measurement pulses of the EIS measurement depending on an output signal from the torque sensor, the rotation angle sensor, the speed sensor, and / or the acceleration sensor. Thus, further interactions between the EIS measurement and the locomotion or conditions between them can be monitored.

[0042] According to one aspect of the invention, the electrical system may include a slip sensor, a yaw rate sensor, a brake sensor, and / or a crash sensor communicatively connected to the EIS unit, wherein the EIS unit includes a measurement stop section for stopping the EIS measurement depending on an output signal from the slip sensor, the yaw rate sensor, the brake sensor, and / or the crash sensor. Thus, further interactions between the EIS measurement and the locomotion or conditions between them can be monitored.

[0043] According to one aspect of the invention, the means of transport may be a battery electric vehicle, a fuel cell vehicle, a hybrid vehicle, a rail vehicle, a boat, an aircraft, an air taxi or a drone.

[0044] According to one aspect of the invention, the power electronics can comprise a power transistor with a SiC semiconductor, with which the EIS actuator section interacts. This semiconductor technology allows the frequency spectrum of the EIS to be extended up to 40 kHz.

[0045] According to one aspect of the invention, the power electronics (11, 12) can comprise a power transistor with a GaN semiconductor, with which the EIS actuator section interacts. This semiconductor technology allows the frequency spectrum of the EIS to be extended up to 100 kHz.

[0046] According to one aspect of the invention, the power electronics (11, 12) can comprise a multilevel inverter (MLI) with which the EIS actuator section interacts. This power electronics allows for a smoother gradation of the measurement pulse edges and thus improved measurement resolution.

[0047] According to one aspect of the invention, the EIS unit can comprise a data memory for storing data of the determined impedance values ​​or states of the electrochemical energy source derived therefrom, and a data interface, in particular a radio data interface, for transmitting the stored data to an external database. Thus, a comprehensive collection of data can be generated, collected, and centrally consolidated directly at the user's site. With regard to the method, according to one aspect of the invention, the step of converting can comprise power conversion of an electrical power provided by the electrochemical energy source by means of the power electronics and modulation of a multi-phase three-phase current for driving at least one drive motor of the means of transport, wherein the steps of impressing and superimposing the measuring pulses can take place while the means of transport is moving.Thus, the measurements can be taken while driving and implemented in a drive inverter for a drive motor using the suitable and already existing power electronics technology, whereby the measuring pulses can be kept so small that they do not affect the driving characteristics.

[0048] According to one aspect of the invention, the transforming step may include different modulations for driving different drive motors. The measurement may be imposed via one or more power transformers.

[0049] According to one aspect of the invention, the converting step may comprise a modulation between a multi-phase three-phase current and an input voltage to the electrochemical energy source for regeneration by a drive motor, or the converting step may comprise a modulation for regeneration by one drive motor and a modulation for driving another drive motor. This allows a reversal of a regenerative power flow during ferry operation, wherein a converted, regenerative charging power can be applied directly to the drive battery device with the superposition of the measurement pulses.

[0050] According to one aspect of the invention, the converting step may comprise a voltage conversion between an output voltage of the electrochemical energy source and a supply voltage for an auxiliary unit, an actuator, and / or on-board electronics of the means of transport. This provides a further option for implementing the invention using existing hardware.

[0051] According to one aspect of the invention, the converting step can comprise at least one power conversion between an externally provided supply power and a charging power of the electrochemical energy source of the transport means by means of the power electronics, and the steps of applying and superimposing the measurement pulses can be performed during a charging process of the transport means. Thus, a charging time can be used for the measurements.

[0052] According to one aspect of the invention, the converting step can comprise a voltage conversion between a charging voltage of a charging power provided by a charging structure for the means of transport and an on-board charging voltage with which the electrochemical energy source is charged on board the means of transport, using the power electronics. Thus, there is another option for implementing the invention using existing hardware, specifically in direct connection with the drive battery device.

[0053] According to one aspect of the invention, the converting step can comprise rectifying a supply voltage of the supply power into the charging voltage of the charging power provided by a charging structure for the means of transport by means of the power electronics. Thus, another option exists for implementing the invention using existing hardware, specifically in direct connection with the drive battery device.

[0054] According to one aspect of the invention, the EIS measurement pulses impressed in step 1 or the commands for the EIS measurement pulses output in step 2 can comprise an excitation signal with an algorithmic or pseudorandom binary sequence. According to the inventors' current findings, such modulation of the measurement pulses improves the measurement results.

[0055] According to one aspect of the invention, the method may comprise a step of analyzing an aging state of the electrochemical energy source from the impedance values ​​determined in step at different frequencies of the measuring pulses.

[0056] According to one aspect of the invention, the method may comprise a step of analyzing a state of charge (SOC) of the electrochemical energy source, in particular a drive battery device, from the impedance values ​​determined in step at different frequencies of the measuring pulses.

[0057] According to one aspect of the invention, the method may comprise steps for storing data of the determined impedance values ​​or of states of the electrochemical energy source derived therefrom in a data storage device; and for transmitting the stored data to an external database via a data interface, in particular a radio data interface. Thus, a manufacturer or service provider is provided with a large amount of data, which enables empirical investigations into model-specific findings.

[0058] Further advantages, features, and details of the invention will become apparent from the following description, which describes embodiments of the invention in detail with reference to the drawings. The features and embodiments mentioned in the claims and in the description may be essential to the invention individually or in any combination. They show schematically:

[0059] Fig. 1 is a block diagram showing the allocation of components of the electrical system in an embodiment of the invention;

[0060] Fig. 2 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0061] Fig. 3 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0062] Fig. 4 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0063] Fig. 5 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0064] Fig. 6 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0065] Fig. 7 is a block diagram for the assignment of components of the electrical system in another embodiment of the invention;

[0066] Fig. 8 is a flowchart showing a sequence of steps of the method in one embodiment of the invention;

[0067] Fig. 9 is a flowchart illustrating a sequence of steps of the method in another embodiment of the invention; Fig. 10 is a diagram illustrating measurement curves in an implementation of the electrical system and method in one embodiment of the invention;

[0068] Fig. 11 is a diagram illustrating a relationship known in the prior art between EIS measurements and an equivalent circuit diagram of a fuel cell;

[0069] Fig. 12 is a diagram of a known relationship between EIS measurements and an equivalent circuit diagram of a fuel cell; and

[0070] Fig. 13. a labeled technical circuit diagram for the control and regulation technical concretization of an embodiment of components of the electrical system.

[0071] Fig. 1 shows a schematic block diagram of the electrical system 100 for determining impedance values ​​of an electrochemical energy source 13, which in this embodiment is a traction battery device 13B, on board a means of transport 10. The electrical system comprises a mobile on-board section 101 installed on board a means of transport 10, and in some embodiments described later, it optionally comprises, instead of or in addition, a stationary charging structure section 102.

[0072] With reference to Fig. 2, the on-board section 101 of the electrical system 100 comprises electrical conductors connected to an electrochemical energy source 13 arranged on board the means of transport 10 to provide electrical power for propelling the means of transport 10. In this exemplary embodiment, the electrochemical energy source 13 is a fuel cell device 13FC, which generates the electrical power on board from process gases, or a drive battery device 13B, which stores the electrical power as a result of a charging process on board. Furthermore, the electrical system comprises sensors 14, such as a current sensor and a voltage sensor, which detect an output voltage via outputs of the electrochemical energy source 13 and a current through the electrochemical energy source 13.

[0073] The sensors 14, like the power electronics 11, can be part of a vehicle system such as a drive train of a vehicle, ie they are already conventionally provided in an electrically driven vehicle which does not have the electrical system according to the invention, and are also required for various essential operating functions, such as range detection and power limitation or monitoring of a vehicle.

[0074] In addition, the electrical system 100 includes an electrochemical impedance spectroscopy (EIS) unit 15 for performing EIS measurements, which is signal-connected to the sensors 14 and the power electronics 11 in the on-board section 101. The EIS unit 15 is implemented on a microcomputer or a CPU, e.g., in a control unit 16 of the means of transport 10 or a battery management system (BMS) 17 thereof.

[0075] Returning to Fig. 1, in an embodiment in which the electrochemical energy source 13 of the means of transport 10 is embodied as a rechargeable drive battery device 13B, the electrical system 100 can optionally comprise a charging structure section 102 instead of or in addition to the on-board section 101. The charging structure section 102 can be electrically connected to the on-board section 101 or at least to the drive battery device 13B on board the means of transport 10 via a charging power connection temporarily established by means of detachable plug contacts. The charging structure section 102 comprises a charging device 20 for providing a charging infrastructure for the means of transport 10 with a charging power for the drive battery device 13B of the means of transport 10. The charging structure section 102 is connected to a supply network 200, which feeds in a supply power with a high supply AC voltage.A supply voltage converter 21 is arranged in the charging device 20 of the charging structure section 102 and, by means of rectification and voltage conversion, converts the high supply AC voltage into a lower charging DC voltage for a charging power that is suitable for feeding into the on-board section 101 or at least into the drive battery device 13B of the means of transport 10.

[0076] In the following embodiments, the means of transport 10 is an electrically powered vehicle, such as in particular a car or a truck. Furthermore, the means of transport can also be another land vehicle, such as a rail vehicle, an aircraft such as a powered airplane, an air taxi, a helicopter or a drone, or a watercraft, such as an electrically powered smaller boat or a larger ship, or the like. Accordingly, a drive or a drive motor 30 of the means of transport in the following embodiments refers to a traction drive. In other embodiments, the electric drive motor 30 is part of a fluid-specific propeller drive, impeller drive, or screw drive for aircraft or watercraft.

[0077] With reference to Fig. 3, the power electronics 11 of the on-board section 101 comprises a drive inverter 31 on board the means of transport 10, which supplies and controls one or more drive motors 30 with drive power. For this purpose, the drive inverter 31 draws electrical power from the electrochemical energy source 13 and converts it into a multi-phase, e.g., three-phase or six-phase, alternating current by means of a power transistor, which serves as and can be referred to as the conversion section of the power electronics 11. In particular, the drive inverter 31 can control and supply multiple drive motors 30 separately, or comprise multiple inverter units operating in parallel, which enable separate control and supply of multiple drive motors 30. The separately controlled and supplied drive motors 30 can, for example, be assigned to multiple drive axles or multiple drive wheels of the means of transport 10.The power electronics 11 also includes a power transistor, which is signal-connected to the EIS unit 15 to receive commands for measuring pulses for the EIS. This power inverter is used to convert the measuring pulses and can be referred to as the EIS actuator section of the power electronics 11. The power transistor is part of the drive inverter 31 or is connected in parallel to the drive inverter 31, whereby the power transistor applies or impresses the measuring pulses during the power conversion of the drive inverter 31, i.e., during the modulation of the multi-phase three-phase current. The power conversion and the measuring pulses are superimposed in a superposition section of the power electronics 11 and output from the power electronics 11 as the resulting, superimposed, converted power.A conductor section upstream of or at a power output of the power electronics 11, in particular at a power output of the drive inverter 31 to one or more drive motors 30, can serve as the superposition section. The power transistor serving as the conversion section and the power transistor serving as the EIS actuator section can thus be two separate power transistors, both arranged in the drive inverter 31 or arranged separately and connected in parallel. In a modified embodiment, the conversion section and the EIS actuator section are implemented by one and the same power transistor in the drive inverter 31.A superposition section is a signal path in front of a control signal input of the power transistor, whereby in the signal path command signals for power conversion and the command signals of the measuring pulses are superimposed as analog signals, or in a digital signal path they are superimposed in a temporal resolution.

[0078] With reference to Fig. 4, the power electronics 11 of the on-board section 101 in another embodiment comprises a DC-DC converter 37 on board the means of transport 10, which converts an output voltage of the electrochemical energy source 13 into an operating voltage for one or more auxiliary units such as an air conditioning compressor, a coolant pump, a hydraulic pump of a commercial vehicle or the like, or into an operating voltage for actuators such as electrically operated valves, window lifters, etc., or into an operating voltage for on-board electronics such as the control unit 16.

[0079] In this embodiment, the power electronics 11 also includes a power transistor that is signal-connected to the EIS unit 15 to receive commands for measurement pulses for the EIS. This power inverter serves to convert the measurement pulses and can be referred to as the EIS actuator section of the power electronics 11. The power transistor is part of the DC-DC converter 37 or is connected in parallel to the DC-DC converter 37, wherein the power transistor applies or impresses the measurement pulses during the power conversion of the DC-DC converter 37, i.e., during the voltage conversion from a higher DC voltage of the output voltage of the electrochemical energy source 13 to a lower DC voltage of one of the aforementioned operating voltages.As previously described, the power conversion and the measurement pulses are superimposed in a superposition section of the power electronics 11 and output as the resulting, superimposed, converted power from the power electronics 11. A conductor section upstream of or at a power output of the power electronics 11, in particular a power output of the DC-DC converter 37 to an on-board power system with an auxiliary unit, actuator, or on-board electronics, in particular to the on-board section 101, can serve as the superposition section. A power transistor or resistor of the DC-DC converter 37 serving as the conversion section and the power transistor serving as the EIS actuator section can be two separate electrical components, both arranged in the DC-DC converter 37 or arranged separately and connected in parallel.

[0080] In a modified embodiment, the conversion section and the EIS actuator section are implemented by one and the same power transistor in the DC-DC converter 37. A superposition section is a signal path upstream of a control signal input of the power transistor, wherein command signals for power conversion and the command signals of the measurement pulses are superimposed as analog signals in the signal path, or are superimposed in a digital signal path with temporal resolution.

[0081] With reference to Fig. 5, the power electronics 11 of the on-board section 101, in another embodiment, comprises a charging voltage converter 39 arranged in an on-board charging device of the means of transport 10, wherein the means of transport 10 in this case is equipped with a drive battery device 13B as the electrochemical energy source 13. The charging voltage converter 39 converts a charging voltage of a charging power provided by a charging structure, in particular by the charging structure section 102 of the electrical system 100 for the means of transport 10, into an on-board charging voltage with which the drive battery device 13B is charged on board.

[0082] In this embodiment, the power electronics 11 also includes a power transistor that is signal-connected to the EIS unit 15 to receive commands for measurement pulses for the EIS. This power inverter is used to convert the measurement pulses and can be referred to as the EIS actuator section of the power electronics 11. The power transistor is part of the charging voltage converter 39 or is connected in parallel to the charging voltage converter 39, whereby the power transistor applies or impresses the measurement pulses during the power conversion of the charging voltage converter 39. The power conversion and the measurement pulses are superimposed in a superposition section of the power electronics 11 as previously described and output from the power electronics 11 as the resulting, superimposed, converted power.A conductor section upstream of or at a power output of the power electronics 11, in particular at a power output of the charging voltage converter 39 to the drive battery device 13B, in particular via the on-board section 101, can serve as the superposition section. A power transistor or resistor of the DC-DC converter 37 serving as a conversion section and the power transistor serving as the EIS actuator section can be two separate electrical components, both arranged in the DC-DC converter 37 or arranged separately and connected in parallel.

[0083] In a modified embodiment, the conversion section and the EIS actuator section are implemented by one and the same power transistor in the charging voltage converter 39. A superposition section is a signal path upstream of a control signal input of the power transistor, wherein command signals for power conversion and the command signals of the measurement pulses are superimposed as analog signals in the signal path, or are superimposed in a digital signal path with temporal resolution.

[0084] With reference to Fig. 6, in a further embodiment, the electrical system 100 comprises the charging structure section 102 with the power electronics 12. The power electronics 12 comprise a supply voltage converter 21, which converts a high AC voltage of a supply power, which is provided from an external supply network 200, into a charging voltage of a charging power provided at the charging device 20 of the charging structure section 102 for the means of transport 10. In this case, too, the means of transport 10 is equipped with a drive battery device 13B as the electrochemical energy source 13. Furthermore, the EIS unit 15 of the electrical system 100 is arranged in the charging structure section 102 and is signal-connected to the power electronics.For this purpose, the EIS unit 15 can be signal-connected to the sensors 14 of the electrical system 100 on board the means of transport 10 via a detachable, temporarily established communication connection. The communication connection can be integrated into the charging connection via plug contacts or implemented via a radio connection between the charging device 20 and the means of transport 10, preferably between the charging structure section 102 and the on-board section 101 of the electrical system.

[0085] The power electronics 12 includes a power transistor that is signal-connected to the EIS unit 15 to receive commands for measurement pulses for the EIS. This power inverter is used to convert the measurement pulses and can be referred to as the EIS actuator section of the power electronics 11. The power transistor is part of the supply voltage converter 21 or is connected in parallel with the supply voltage converter 21, whereby the power transistor applies or impresses the measurement pulses during the power conversion of the supply voltage converter 21. The power conversion and the measurement pulses are superimposed in a superposition section of the power electronics 11 as previously described and output from the power electronics 12 as the resulting, superimposed, converted power.A conductor section upstream of or at a power output of the power electronics 11, in particular at a power output of the supply voltage converter 21 to the charging connection, can serve as the superposition section. A power transistor of the supply voltage converter 21 serving as a conversion section and the power transistor serving as the EIS actuator section can be two separate electrical components, both arranged in the supply voltage converter 21 or arranged separately and connected in parallel.

[0086] In a modified embodiment, the conversion section and the EIS actuator section are implemented by one and the same power transistor in the supply voltage converter 21. A superposition section is a signal path upstream of a control signal input of the power transistor, wherein command signals for power conversion and the command signals of the measurement pulses are superimposed as analog signals in the signal path, or are superimposed in a digital signal path with temporal resolution.

[0087] In all previously described embodiments, impulse responses that arise as a reaction of the electrochemical energy source 13 to the measurement pulses introduced into the on-board section 101 or electrical connections to the electrochemical energy source 13 are detected by the sensors 14, particularly in the form of a voltage across and a current through the electrochemical energy source 13. The measurements are communicated by the sensors 14 to the EIS unit 15 via signals.

[0088] With reference to Fig. 7, as already mentioned, the EIS unit 15 is implemented on a microcomputer like the control unit 16. A subroutine of the EIS unit 15 generates commands for calculated measurement pulses with different EIS frequencies and can be referred to as the pulse command section. Another subroutine of the EIS unit 15 processes the incoming measurement signals received from the sensors and can be referred to as the measurement reception section. Another subroutine of the EIS unit 15 determines impedance values ​​of the electrochemical energy source 13 from the processed measurement signals or from those compared with stored impedance values ​​and can be referred to as the determination section.

[0089] In the case where the electrochemical energy source 13 is embodied as a drive battery device 13B, the means of transport may also include a battery management system (BMS) for monitoring states of the drive battery device 13B. In this context, in one embodiment, the EIS unit 15 may be implemented in the BMS or jointly with it on the control unit 16.

[0090] In the aforementioned embodiments, a downstream analysis section is also implemented in the form of a further subprogram, which is assigned to the EIS unit 15, the control unit 16, or the BMS 17, or is executed on a common microcomputer of the latter. The analysis section processes the measurements or compares them with stored values ​​and thus determines a state of the electrochemical energy source 13. The states determined by the analysis section are preferably an aging state, also called a state of health (SoH), or a state of charge, also called a state of charge (SoH).

[0091] The states are stored in a data memory so that they can be used for further operational functions, such as safety measures, user notifications, function limitations, or preventive measures of an operational control system in the means of transport 10. Furthermore, the stored data on the states are transmitted via a communication connection of an external diagnostic device for maintenance of the means of transport 10, or continuously transmitted via a radio connection to an external database of a service provider.

[0092] Fig. 8 shows a flowchart that schematically illustrates the essential steps of the method. The starting point is initially a power conversion, which is also conventionally carried out in ferry operation, i.e., during movement F of the means of transport, by the power electronics 11 for an operating function. In one exemplary embodiment, step S51 represents the power conversion of the drive inverter 31, which, for example, supplies and controls a drive motor 30 on a rear axle and a drive motor on a front axle of the means of transport 10 with converted power from the electrochemical energy source 13.

[0093] During locomotion F, EIS measurements are performed in order to draw conclusions about the state of the electrochemical energy source 13 through subsequent analyses of the measured impedance values. For this purpose, the pulse command section of the EIS unit 15, which includes a signal output, outputs commands for measurement pulses with various frequencies across a predetermined frequency spectrum to the power electronics 11 with the drive inverter 31 or directly to the drive inverter 31 in step S10. In step S20, a power transistor of the power electronics 11, in particular a power transistor of the drive inverter 31, which also already performs the power conversion to supply and control the drive motors 30, implements the received commands.The implementation consists in introducing, i.e. generating and impressing the measuring pulses for the EIS according to the commands onto a power output of the power electronics 11, in particular of the drive inverter 31 itself. At the same time, in step S25, amplitudes and frequencies of the introduced measuring pulses are superimposed with amplitudes and frequencies of the converted drive power, i.e. with the multi-phase three-phase current.

[0094] In step S30, the sensors 14, which comprise at least one voltage sensor 14 for detecting a voltage between power outputs of the electrochemical energy source 13 and one current sensor for detecting a current through the power outputs of the electrochemical energy source 13, detect impulse responses that arise in response to the excitation of the measurement pulses at the electrochemical energy source 13. The EIS unit 15 receives the voltages and currents measured by the sensors 14 to an impedance at the power outputs of the electrochemical energy source 13 in the form of measurement signals at signal inputs of a receiving section of the EIS unit 15.A determination section of the EIS unit, which is implemented as a subprogram on the microcomputer, processes or compares with stored values ​​the amplitudes and frequencies of the received measurement signals in relation to characteristics of impedances and determines an impedance value of the electrochemical energy source 13. In a further method step, not further shown, an aging state or a charge state of the electrochemical energy source 13 is determined by data processing or comparisons with stored characteristic maps in a known manner.

[0095] In another embodiment, the drive inverter 31 with a plurality of parallel inverter stages or inverter subunits, on the one hand, carries out power conversion to supply and control the one drive motor 30 on one vehicle axle and, on the other hand, recuperation, i.e. power conversion to regenerate power at the drive motor 30 on another vehicle axle. In this case, a power distribution between a drive mode and a regeneration mode is controlled such that a power flow to the driving drive motor 30 on one vehicle axle is greater than a reverse power flow to the regenerating drive motor 30 on the other vehicle axle. In other words, a regenerating power flow is controlled to be smaller than a driving power flow, so that the means of transport 10 moves, i.e. a movement F takes place. Likewise, decelerations orReductions in speed or fluctuations in it can be used for these processes.

[0096] The power conversion of the regeneration comprises rectifying a three-phase current generated at the drive motor 30 into a direct current or a direct voltage for charging a drive battery device 13B, wherein the power inputs and power outputs of a power transistor of the drive inverter 31 are reversed compared to a drive mode thereof due to the reversed power flow between the drive motor 30 and the drive battery device 13B through the drive inverter 31. In steps S20 and S25, the measurement pulses are impressed and superimposed simultaneously with the conversion of the regenerated charging power by the same power transistor to the power output of the drive inverter 31 to the drive battery device 13B, which was previously a power input in the drive mode.Advantageously, a direct application of the converted regenerative charging power superimposed with the measuring pulses to the drive battery device 13B is thus achieved.

[0097] In further embodiments, other power conversions occur in step S51 during the movement F of the transport means 10 as the starting point for otherwise similar method steps as described above. Thus, the EIS unit 15 can interact with other parts of the power electronics 11 to convert the measurement pulses and superimpose them with a converted power.

[0098] In another embodiment, in step S51, the voltage converter 37 converts the output voltage of the electrochemical energy source 13 into an operating voltage of, for example, one of the auxiliary units. At the same time, the same power transistor of the voltage converter 37 that performs the power conversion applies the measurement pulses commanded by the EIS unit to the converted power with the operating voltage for the auxiliary unit.

[0099] In a further embodiment, in step S51, the charging voltage converter 39 converts the provided charging voltage into an on-board charging voltage corresponding to the absorbed charging power of a drive battery device 13B. At the same time, the same power transistor of the charging voltage converter 39 that performs the power conversion applies the measurement pulses commanded by the EIS unit to the converted power with the operating voltage for the auxiliary power unit. This advantageously involves a direct application of the converted power, superimposed with the measurement pulses, to the drive battery device 13B.

[0100] Since the amplitudes and frequencies of the measurement pulses, as well as the pulse responses, propagate via the electrical conductors on board the means of transport 10, in particular the on-board section 101, they can always cause an impedance in the electrochemical energy source 13 in response to the measurement stimulus. Preferably, the sensors 14 and also the power transistors for converting the measurement pulses are arranged directly or as close as possible to the power outputs of the electrochemical energy source 13.

[0101] In a further embodiment, the measurement pulses can be superimposed on a power input of a power inverter of the drive inverter 31 or the voltage converter 37, which is electrically connected to the electrochemical energy source 13. Thus, the pulse propagation for measurement excitation can be applied more specifically and directly to the electrochemical energy source 13 or drive battery device 13B.

[0102] Referring to Fig. 9, a flowchart is shown that schematically illustrates the steps of an alternative embodiment of the method. The starting point in step S52 is the power conversion of the power electronics 12 with the supply voltage converter 21, which converts a supply power, such as from the external supply network 200, into the charging voltage of a provided charging power, in particular from the charging device 20 of the charging structure section 200, during a conventional charging process L of the means of transport 10.

[0103] In step S10, the EIS unit 15 interacts with a power transistor of the power electronics 12 in the supply voltage converter 21 by issuing commands to convert the measurement pulses and superimpose them on the converted charging power. The power transistor of the supply voltage converter 21 converts the supply power into the charging power in step S52 and, in step S20, impresses the measurement pulses onto the converted power. At the same time, in step S25, the converted charging power is superimposed with the impressed measurement pulses at a power output of the power electronics 12, preferably at a power output of the supply voltage converter 21, and output to a charging connection to the means of transport 10. In step S30, the EIS unit 15 receives the measurements from the sensors 14 via a communication connection, from which the impedance values ​​are determined in step S40.

[0104] Fig. 10 schematically shows measured values ​​from sensors 14 that were recorded in the method from Fig. 8, i.e., during a movement F, using the embodiment of the electrical system 100 in which the drive inverter 31 interacts with the EIS unit 15. In phases 1 and 3, the means of transport 10 starts moving, or is subject to acceleration or deceleration. During these phases, no EIS measurements are taken in order not to impair driving stability or at least driving comfort, and to obtain a better, more constant starting position for the power transmission of the measurement pulses and pulse responses, which can be impaired, for example, by interactions of a torque ripple, which tends to occur more frequently in dynamic driving situations under load. Phase 2 represents continuous movement, such as driving at a fixed speed using cruise control.In phase 2, EIS measurements are preferably carried out according to the procedure described above.

[0105] In an embodiment according to Fig. 10, the EIS unit 15 is also connected to a speed sensor. The pulse command section can start and stop issuing commands for measurement pulses or adjust their intensity depending on the continuity of the speed of movement F, ie, the detection and differentiation between phases 2 or phases 1 and 2.

[0106] The intensity of the measuring pulses is adjusted via a control loop as a function of a torque ripple of a drive motor 30 in response to the supplied drive power superimposed on the measuring pulses, with feedback from measured values ​​of a torque sensor, a rotation angle sensor, an acceleration sensor or the speed sensor connected to the EIS unit 15, and taking into account predetermined limit values ​​for the respective measured values.

[0107] Detection of phases of continuous movement F is carried out via a slip sensor, a yaw rate sensor, a brake sensor, or a crash sensor, which are connected to the EIS unit 15, and taking into account predetermined limit values ​​for the respective measured values.

[0108] In a further embodiment, an additional superposition of multiple frequencies of simultaneous measurement pulses is performed by multiple drive inverters 31 for multiple drive motors 30, thereby shortening the required duration for the EIS measurements.

[0109] In all of the aforementioned embodiments, the measurement pulses are preferably applied to a high-voltage bus of an electric drive train or, alternatively, to a DC bus of an on-board electrical system. The pulse responses with respect to the voltage are measured using existing sensors 14 in a drive train or on-board electrical system, preferably the on-board section 101 of a means of transport 10, at a bus voltage or a cell voltage.

[0110] If an existing power inverter of the transport means 10 is used to implement the invention, which does not have a chip with a SiC semiconductor or GaN semiconductor, the frequency spectrum of the measuring pulses, in particular for fuel cells in the EIS, can be limited to 1 or 2 kHz.

[0111] Fig. 11 schematically illustrates a prior art mapping between an equivalent circuit diagram of a fuel cell and a diagram of frequency-dependent impedance values ​​for evaluation. Methods for such EIS-based state analyses, which are based on the determined impedance values ​​from the described system and method, are known in the prior art and will not be explained further in order to focus the disclosure on the subject matter of the invention. The same applies to Fig. 12, which similarly shows a mapping between an equivalent circuit diagram of a battery and a diagram of frequency-dependent impedance values.

[0112] Fig. 13 shows a control and regulation technology at the detailed level of a technical circuit diagram. The dashed boundaries in the technical circuit diagram highlight logical blocks and circuit sections for measuring and controlling hardware, which represent a concrete embodiment for implementing the previously described functional components of the electrical system 100 based on conventional technology. The technical diagram contains self-explanatory labels as well as internationally standardized symbols and parameters that are understandable to those skilled in the art.

[0113] The above explanations of the embodiments describe the present invention exclusively by way of examples. Of course, individual features of the embodiments can be freely combined with one another, provided they are technically feasible, without departing from the scope of the present invention.

[0114] List of reference symbols

[0115] 10 means of transport

[0116] 11 Power electronics in the on-board section

[0117] 12 Power electronics in the charging structure section

[0118] 13 electrochemical energy source

[0119] 13B Traction battery device

[0120] 13FC fuel cell device

[0121] 14 sensors

[0122] 15 Electrochemical impedance spectroscopy (EIS) unit

[0123] 16 Control unit

[0124] 17 Battery Management System (BMS)

[0125] 20 loading device

[0126] 21 supply voltage converter

[0127] 30 drive motor

[0128] 31 drive inverters

[0129] 33 Auxiliary unit

[0130] 35 On-board electronics

[0131] 37 DC-DC converters

[0132] 39 charging voltage converter

[0133] 100 electrical system for determining impedance values

[0134] 101 On-board section of the electrical system

[0135] 102 Charging structure section of the electrical system

[0136] 200 supply network

[0137] F Movement

[0138] L Charging process

Claims

Patent claims 1. Electrical system (100) for determining impedance values ​​of an electrochemical energy source (13) of an electrically driven means of transport (10) by means of electrochemical impedance spectroscopy (EIS), comprising: an on-board section (101) of the electrical system (100) which is arranged on board the means of transport (10) and is connected to the electrochemical energy source (13) is electrically connected to a power electronics unit (11) for converting an electrical power provided from the electrochemical energy source (13) in the on-board section (101); and / or a charging structure section (102) which is arranged in a charging device (20) and is electrically connectable to the electrochemical energy source (13) of the means of transport (10) via a temporarily established charging connection, with a power electronics unit (12) for converting a supply power provided from an external supply network (200) in the charging structure section (102); and Sensors (14) for detecting parameters of electrical operating states of the electrochemical energy source (13); and an EIS unit (15) for determining impedance values ​​of the electrochemical energy source (13) by means of EIS, wherein the EIS unit (15) is arranged in the on-board section (101) and is connected to the power electronics (11) and the sensors (14) is communicatively connected, and / or the EIS unit (15) is arranged in the charging structure section (102) and is communicatively connected to the power electronics (12) and is connectable to the sensors (14) via a temporarily established communication connection, wherein the EIS unit (15) comprises: a pulse command section for issuing commands for measurement pulses which are impressed on the electrochemical energy source (13) for an EIS, a measurement reception section for receiving measurements of pulse responses which are derived from an impedance of the electrochemical energy source (13) and in response to the measurement pulses of the EIS, and which are detected by means of the sensors (14); and a determination section for determining impedance values ​​of the electrochemical energy source (13) from the received measurements of the impulse responses; and wherein the power electronics (11, 12) comprise: an EIS actuator section for impressing the measurement pulses of the EIS in accordance with the output commands of the EIS unit (15) onto a converted electrical power for the means of transport (10) by means of the power electronics (11, 12); a conversion section for the power conversion of the power electronics (11, 12), and a superposition section for superimposing the converted electrical power with the impressed measurement pulses of the EIS before delivery to an electrical connection with the electrochemical energy source (13).

2. Electrical system (100) according to claim 1, wherein the electrochemical energy source (13) on board the means of transport (10) is a fuel cell device (13FC).

3. Electrical system (100) according to claim 1, wherein the electrochemical energy source (13) on board the means of transport (10) is a drive battery device (13B).

4. The electrical system (100) according to any one of claims 1 to 3, wherein the EIS unit (15) further comprises an analysis section for analyzing a state of aging (SOH) of the electrochemical energy source (13) from the determined impedance values ​​at different frequencies of the measuring pulses.

5. The electrical system (100) according to claim 3, wherein the EIS unit (15) further comprises an analysis section for analyzing a state of charge (SOC) of the drive battery device (13B) from the determined impedance values ​​at different frequencies of the measurement pulses.

6. Electrical system (100) according to one of claims 1 to 5, wherein the power electronics (11) of the on-board section (101) comprises a drive inverter (31) for power control of at least one drive motor (30) of the means of transport (10), which cooperates with the EIS actuator section.

7. Electrical system (100) according to one of claims 1 to 5, wherein the power electronics (11) of the on-board section (101) comprises a DC-DC converter (37) for supplying power to an auxiliary unit (33), an actuator and / or on-board electronics (35) of the means of transport (10), which cooperates with the EIS actuator section.

8. Electrical system (100) according to one of claims 3 to 5, wherein the power electronics (11) of the on-board section (101) comprises a charging voltage converter (39) for charging the drive battery device (13B) on board the means of transport (10), which cooperates with the EIS actuator section.

9. Electrical system (100) according to one of claims 3 to 5, wherein the power electronics (12) of the charging structure section (102) has a supply voltage converter (21) for providing a charging power for the electrically connectable means of transport (10), which cooperates with the EIS actuator section.

10. Electrical system (100) according to one of claims 1 to 9, wherein the power conversion of the power electronics (11), which is superimposed with the measuring pulses from the EIS actuator section, comprises a modulation between an output voltage from the electrochemical energy source (13) and a multi-phase three-phase current for driving the at least one drive motor (30), or different modulations for driving different drive motors (30).

11. Electrical system (100) according to one of claims 1 to 9, wherein the power conversion of the power electronics (11), which is superimposed with the measuring pulses from the EIS actuator section, comprises a modulation between a multi-phase three-phase current and an input voltage into the electrochemical energy source (13) for regeneration by one of the at least one drive motor (30), or a modulation for regeneration by one drive motor (30) and a modulation for driving another of the at least one drive motor (30).

12. Electrical system (100) according to one of claims 1 to 9, wherein the power conversion of the power electronics (11), which is superimposed with the measuring pulses from the EIS actuator section, comprises a voltage conversion between an output voltage of the electrochemical energy source (13) and a supply voltage for the auxiliary unit (33), the actuator and / or the on-board electronics (35) of the means of transport (10).

13. Electrical system (100) according to one of claims 3 to 9, wherein the power conversion of the power electronics (11), which is superimposed with the measuring pulses from the EIS actuator section, comprises a voltage conversion between a charging voltage provided by the charging structure section (102) of the electrical system (100) for the electrically connectable means of transport (10), and a charging voltage with which the drive battery device (13B) in the on-board section (101) of the electrical system (100) is charged.

14. Electrical system (100) according to one of claims 3 or 9, wherein the power conversion of the power electronics (12), which is superimposed with the measuring pulses from the EIS actuator section, comprises a power conversion between a supply power provided from an external supply network (200) and a charging power provided by the charging structure section (102) of the electrical system (100) for the means of transport (10).

15. Electrical system (100) according to one of claims 1 to 14, wherein the transport means (10) has a control unit (16) for controlling operating functions of the means of transport (10), which is communicatively connected to the power electronics (11) and to the sensors (14) in the on-board section (101), and wherein the EIS unit (15) of the electrical system (100) is integrated in the control unit (16).

16. Electrical system (100) according to one of claims 3 to 15, wherein the means of transport (10) has a battery management system (BMS) (17) for monitoring operating states of the drive battery device (13B), which is communicatively connected in the on-board section (101) to the power electronics (11) and to the sensors (14), and wherein the EIS unit (15) of the electrical system (100) is integrated in the BMS (17).

17. Electrical system (100) according to one of claims 3, 9 or 14, wherein the EIS unit (15) in the charging structure section (102) is communicatively connected to the power electronics (12) and is integrated in the charging device (20).

18. Electrical system (100) according to one of claims 1 to 17, wherein the sensors (14) for detecting parameters of electrical operating states comprise a current sensor and a voltage sensor for measuring impedance in electrical connections to or at power outputs of the electrochemical energy source (13).

19. Electrical system (100) according to one of claims 1 to 18, comprising at least one sensor (14) for detecting parameters of movement-dynamic operating states of the means of transport (10), preferably a speed sensor, which is communicatively connected to the EIS unit (15).

20. Electrical system (100) according to one of claims 1 to 19, comprising a torque sensor, a rotation angle sensor, a speed sensor and / or an acceleration sensor which is communicatively connected to the EIS unit (15), wherein the EIS unit (15) comprises a measurement pulse limiting section for limiting an intensity of the measurement pulses of the EIS measurement as a function of an output signal of the torque sensor, the rotation angle sensor, the speed sensor and / or the acceleration sensor.

21. Electrical system (100) according to one of claims 1 to 20, comprising a slip sensor, a yaw rate sensor, a brake sensor, and / or a crash sensor communicatively connected to the EIS unit (15), wherein the EIS unit (15) comprises a measurement stop section for stopping the EIS measurement in dependence on an output signal of the slip sensor, the yaw rate sensor, the brake sensor, and / or the crash sensor.

22. Electrical system (100) according to one of the preceding claims 1 to 21, wherein the means of transport (10) is a battery electric vehicle, a fuel cell vehicle, a hybrid vehicle, a rail vehicle, a boat, an aircraft, an air taxi or a drone.

23. Electrical system (100) according to one of the preceding claims 1 to 22, wherein the power electronics (11, 12) comprises a power transistor with a SiC semiconductor, with which the EIS actuator section cooperates.

24. Electrical system (100) according to one of the preceding claims 1 to 22, wherein the power electronics (11, 12) comprises a power transistor with a GaN semiconductor, with which the EIS actuator section cooperates.

25. Electrical system (100) according to one of the preceding claims 1 to 24, wherein the power electronics (11, 12) comprises a multilevel inverter (MLI) with which the EIS actuator section cooperates.

26. Electrical system (100) according to one of the preceding claims 1 to 25, wherein the EIS unit (15) comprises a data memory for storing data of the determined impedance values ​​or states of the electrochemical energy source (13) derived therefrom, and a data interface, in particular a radio data interface, for transmitting the stored data to an external database.

27. Method for determining impedance values ​​of an electrochemical energy source (13) of an electrically driven means of transport (10) by means of electrochemical impedance spectroscopy (EIS), preferably by means of a electrical system (100) according to one of claims 1 to 26, comprising the steps: Outputting (S10) commands for measuring pulses of an EIS to be impressed on an electrical power for the means of transport (10); Impressing (S20) the measuring pulses of the EIS onto a converted electrical power in accordance with the commands issued in step S10 by means of power electronics (11, 12); Receiving (S30) measurements of impulse responses resulting from an impedance of the electrochemical energy source (13) and in response to the measurement pulses of the EIS, and which are detected by sensors (14) in electrical connection with the electrochemical energy source (13); and Determining (S40) impedance values ​​of the electrochemical energy source (13) from the received impulse response measurements; with the intermediate steps: Converting (S51) an electrical power provided from the electrochemical energy source (13B, 13FC) for the means of transport (10); or Converting (S52) a supply power provided from an external supply network (200) for charging the electrochemical energy source (13B) of the means of transport (10); and Superimposing (S25) the converted electrical power with the impressed measuring pulses of the EIS before delivery to an electrical connection with the electrochemical energy source (13).

28. The method according to claim 27, wherein the step of converting (S51) comprises a power conversion of an electrical power provided from the electrochemical energy source (13) by means of the power electronics (11) and a modulation of a multi-phase three-phase current for driving at least one drive motor (30) of the means of transport (10), and wherein the steps of Impressing (S20) and superimposing (S25) the measuring pulses during a movement (F) of the means of transport (10).

29. The method according to claim 28, wherein the step of transforming (S51) comprises different modulations for driving different drive motors (30).

30. The method according to claim 28 or 29, wherein the step of transforming (S51) comprises a modulation between a multi-phase three-phase current and an input voltage to the electrochemical energy source (13) for regeneration by one of the at least one drive motor (30), or the step of transforming (S51) comprises a modulation for regeneration by one drive motor (30) and a modulation for driving another drive motor (30).

31. Method according to claim 28, wherein the step of converting (S51) comprises a voltage conversion between an output voltage of the electrochemical energy source (13) and a supply voltage for an auxiliary unit (33), an actuator and / or on-board electronics (35) of the means of transport (10).

32. The method according to claim 27, wherein the step of converting (S52) comprises at least one power conversion between an externally provided supply power and a charging power of the electrochemical energy source (13B) of the transport means (10) by means of the power electronics (11, 12), and wherein the steps of impressing (S20) and superimposing (S25) the measuring pulses take place during a charging process (L) of the transport means (10).

33. The method according to claim 32, wherein the step of converting (S52) comprises a voltage conversion between a charging voltage of a charging power provided by a charging structure for the means of transport (10) and an on-board charging voltage with which the electrochemical energy source (13B) is charged on board the means of transport (10), by means of the power electronics (11).

34. The method according to claim 32, wherein the step of converting (S52) comprises rectifying a supply voltage of the supply power into the charging voltage of the charging power provided by a charging structure for the means of transport (10) by means of the power electronics (12).

35. The method according to any one of claims 27 to 34, wherein the measurement pulses of the EIS impressed in step S20 or the commands for the measurement pulses of the EIS output in step S10 comprise an excitation signal having an algorithmic or pseudorandom binary sequence.

36. Method according to one of claims 27 to 35, comprising the step: Analyzing a state of aging (SOH) of the electrochemical energy source (13) from the impedance values ​​determined in step S40 at different frequencies of the measuring pulses.

37. Method according to one of claims 27 to 36, comprising the step: Analyzing a state of charge (SOC) of the electrochemical energy source (13), in particular a drive battery device (13B), from the impedance values ​​determined in step S40 at different frequencies of the measuring pulses.

38. Method according to one of claims 27 to 37, comprising the steps: Storing data of the determined impedance values ​​or of states of the electrochemical energy source (13) derived therefrom in a data memory; and Transferring the stored data to an external database via a data interface, in particular a radio data interface.

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