Control system for electrical power systems used to control vehicles

Abstract

This invention relates to a control system for an electric power system used to control a vehicle. The electric power system includes: a traction voltage bus; a plurality of batteries, each electrically connected to the traction voltage bus via at least one contactor; the control system includes a corresponding battery control unit for each of the plurality of batteries, and further includes: a main electronic control unit for controlling the plurality of batteries and communicatively connected to each of the battery control units, the main electronic control unit being configured to provide a predetermined electrical interference to the traction voltage bus after a signal has been provided to disconnect at least one contactor of each battery, each battery control unit being configured to detect the predetermined electrical interference, and at least one battery control unit being further configured to issue a signal indicating that the predetermined electrical interference has been detected when the predetermined electrical interference is detected by at least one of the battery control units. The invention also relates to electric power systems, methods, and vehicles.

Description

Technical Field

[0001] This invention relates to a control system for controlling an electrical power system used to propel a vehicle. The invention also relates to an electrical power system for propelling a vehicle, a method for identifying at least one welded contactor in the electrical power system, and a vehicle.

[0002] This invention can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment. Although the invention will be described with respect to at least some electric trucks, it is not limited to this specific vehicle but can also be applied to other vehicles, such as electric buses, electric construction equipment, electric coaches, etc. The invention can also be applied to marine vessels, including an electric power system for propelling the vessel. Background Technology

[0003] The vehicle may include an electric power system and be at least partially propelled by that system. The electric power system may be a high-voltage system having a voltage level of, for example, 400-1000 volts (V). The electric power system may include multiple batteries interconnected via a traction voltage bus (e.g., a high-voltage traction voltage bus). The batteries are configured to supply power to at least one electric traction motor of the vehicle.

[0004] Each battery can be connected to the traction voltage bus via two high-voltage contactors (also known as high-voltage relays). Therefore, by opening and closing the two high-voltage contactors, each battery can be selectively connected to and disconnected from the traction voltage bus.

[0005] In some cases, contactors may fail and become welded, preventing them from disconnecting. In such situations, the traction voltage bus may remain connected to at least one battery even after all contactor signals have been disconnected. This can be extremely dangerous for vehicle users and / or maintenance personnel. Therefore, it is crucial to determine if at least one contactor has been welded.

[0006] In view of the above, there is a need to provide an improved control system and method for identifying when at least one contactor has been welded. Summary of the Invention

[0007] One object of the present invention is to provide an improved control system for controlling an electrical power system used to propel a vehicle, specifically providing an improved control system that provides improved identification of at least one welded contactor. Another object of the present invention is to provide an improved electrical power system for propulsing a vehicle, an improved method for identifying at least one welded contactor in the electrical power system, and an improved vehicle comprising a control system and / or an electrical power system.

[0008] According to a first aspect of the present invention, the above-mentioned objective is achieved by the control system according to claim 1. According to a second aspect of the present invention, the above-mentioned objective is achieved by the electrical power system according to claim 8. According to a third aspect, the above-mentioned objective is achieved by the method according to claim 9. According to a fourth aspect, the above-mentioned objective is achieved by the means of transport according to claim 15.

[0009] According to a first aspect of the invention, the above-mentioned objective is achieved by a control system for controlling an electric power system, wherein the electric power system is used to propel a vehicle. The electric power system comprises:

[0010] Traction voltage bus;

[0011] A plurality of batteries are electrically connected to each other via the traction voltage bus, wherein each battery is electrically connected to the traction voltage bus via at least one contactor. Additionally, the control system includes a corresponding battery control unit for each of the plurality of batteries, wherein the control system further includes:

[0012] A main electronic control unit (NEU) for controlling the plurality of batteries, wherein the NEU is communicatively connected to each of the battery control units, and wherein, after a signal has been provided to disconnect at least one contactor of each battery, the NEU is configured to provide a predetermined electrical interference to the traction voltage bus, and wherein each battery control unit is configured to detect the predetermined electrical interference, and when the predetermined electrical interference is detected by at least one of the battery control units, the at least one battery control unit is further configured to issue a signal indicating that the predetermined electrical interference has been detected.

[0013] Improved identification of contactors that may have been welded is achieved by providing a control system as disclosed herein. Specifically, the invention is based on the understanding that a main electronic control unit (also referred to as an independent and / or central main electronic control unit, which is not part of any of the plurality of batteries) can be advantageously used to perform and participate in or be responsible for the identification process of welded contactors. Specifically, the main electronic control unit is configured to provide predetermined electrical interference that can be identified by each of the battery control units, which means a simplified procedure. Furthermore, the main electronic control unit can identify whether any of the battery contactors has been welded, and more importantly, it can identify which contactors(s) have been welded. Thus, identification can be performed using a single main electronic control unit. This configuration allows for a simplified identification procedure, which, for example, allows a user to quickly identify which contactors(s) have been welded, and subsequently take appropriate action to reduce or mitigate, for example, the risk of personal injury.

[0014] The plurality of batteries (also known as traction batteries) can be of any suitable type, such as lithium-ion batteries, lithium polymer batteries, fuel cells, lead-acid batteries, nickel-metal hydride batteries, etc. The one or more batteries are typically rechargeable.

[0015] The battery control unit can also be referred to as a battery monitoring unit for each battery. Additionally, each battery control unit can be a slave battery control unit, which is configured only to control its own battery and is controlled by the main electronic control unit.

[0016] The statement “each battery control unit is configured to detect predetermined electrical interference” in this document means that the corresponding battery control unit is configured to detect that its battery is subjected to predetermined electrical interference.

[0017] The statement "the main electronic control unit is configured to provide a predetermined electrical interference" in this text can mean that the main electronic control unit is configured to emit a signal that provides a predetermined electrical interference.

[0018] Optionally, each battery control unit can be configured to detect whether the battery experiences voltage drift during a relaxation period after a signal has been provided to disconnect at least one contactor of each battery, and when at least one battery is not experiencing said voltage drift, the battery control unit of said at least one battery is further configured to issue a signal indicating that no voltage drift was detected. Thus, a further improved identification process can be achieved by using the above configuration. More specifically, it has been recognized that voltage drift caused by battery relaxation can be advantageously used to identify welded contactors. Therefore, the absence of voltage drift in the battery is an indication that the battery is still connected to the traction voltage bus. Battery relaxation is well known to those skilled in the art and can be defined as the voltage drop after the battery has been disconnected. Preferably, the battery control unit for said at least one battery can be further configured to issue a signal to the main electronic control unit indicating that no voltage drift was detected. Thus, the main electronic control unit can identify that at least one contactor has been welded.

[0019] Optionally, the main electronic control unit can be further configured to identify whether at least one contactor of at least one of the batteries has been welded before providing a predetermined electrical disturbance to the traction voltage bus. For example, after requiring each battery's contactor to disconnect, the main electronic control unit can identify that a measurable voltage still exists on the traction voltage bus. This provides an indication of a problem, which can then be used to initiate a procedure to identify which contactor(s) have been welded.

[0020] Preferably, the battery control unit for at least one battery can be further configured to send a signal to the main electronic control unit indicating that a predetermined electrical interference has been detected. In this way, the main electronic control unit can also be responsible for actually identifying which contactors / contactors have been welded. More specifically, the invention is based on the understanding that the main electronic control unit can control the entire procedure for identifying which contactors / contactors have been welded, which means simplifying the control system.

[0021] Optionally, the main electronic control unit can be further configured to send a signal to each battery control unit indicating that a predetermined electrical interference will be provided. This allows each battery control unit to prepare when to look for the predetermined electrical interference, which means further improved identification of welded contactors. Alternatively, the signal sent to each battery control unit indicating that a predetermined electrical interference will be provided may include information about the timing of the predetermined electrical interference being provided to the traction voltage bus. Thus, each battery control unit can know when it should look for the predetermined electrical interference, which means further improved identification of welded contactors.

[0022] Optionally, the predetermined electrical interference can be at least one of a predetermined voltage level, a predetermined load, a load with a predetermined current level, and a predetermined frequency level. As used herein, the predetermined electrical interference can be defined as any type of measurable electrical characteristic that can be measured and identified by the battery control unit.

[0023] According to a second aspect of the present invention, the above-mentioned objective is achieved by an electric power system for propelling a vehicle, wherein the electric power system comprises:

[0024] Traction voltage bus;

[0025] Multiple batteries, which are electrically connected to each other via the traction voltage bus, wherein each battery is electrically connected to the traction voltage bus via at least one contactor; and

[0026] The control system according to any embodiment of the first aspect of the present invention.

[0027] The electrical power system mentioned in this article is preferably a high-voltage electrical power system with a voltage level of, for example, 400V-1000V.

[0028] The advantages and effects of the second aspect of the present invention are largely similar to those of the first aspect. Furthermore, all embodiments of the first aspect of the present invention can be applied to and combined with all embodiments of the second aspect of the present invention, and vice versa.

[0029] According to a third aspect of the invention, the above objective is achieved by a method for identifying at least one welded contactor in an electrical power system, wherein the electrical power system is used to propel a vehicle, the electrical power system comprising: a traction voltage bus; a plurality of batteries electrically connectable to each other via the traction voltage bus, wherein each battery is electrically connectable to the traction voltage bus via at least one contactor; and a main electronic control unit for controlling the plurality of batteries, wherein the main electronic control unit is communicatively connected to a corresponding battery control unit for each of the batteries.

[0030] The method includes:

[0031] After a signal has been provided to disconnect at least one contactor of each battery, a predetermined electrical interference is provided to the traction voltage bus using the main electronic control unit;

[0032] For each battery, it is determined whether the predetermined electrical interference is detected, and when the predetermined electrical interference is detected by at least one battery control unit in the battery control unit, a signal indicating that the predetermined electrical interference has been detected is issued from the at least one battery control unit.

[0033] This achieves an improved identification procedure, which can effectively identify which / which contactors have been welded. The advantages and effects of the third aspect of the invention are largely similar to those of the first and second aspects. Furthermore, all embodiments of the third aspect of the invention can be applied to and combined with all embodiments of the first and second aspects, and vice versa.

[0034] Optionally, the method may further include: for each battery, determining whether each battery experiences voltage drift during a relaxation period after a signal has been provided to disconnect at least one contactor of each battery, and when at least one battery is not experiencing voltage drift, issuing a signal from the battery control unit of the at least one battery indicating that it is not experiencing voltage drift.

[0035] Optionally, the method may further include: identifying when at least one contactor of at least one battery in the battery is welded before providing a predetermined electrical interference to the traction voltage bus.

[0036] Optionally, at least one battery control unit can send a signal to the main electronic control unit indicating that a predetermined electrical interference has been detected.

[0037] Optionally, the method may further include: sending a signal to each of the battery control units in the battery control unit indicating that a predetermined electrical interference will be provided.

[0038] Optionally, the predetermined electrical interference can be at least one of a predetermined voltage level, a predetermined load, a load having a predetermined current level, and a predetermined frequency level.

[0039] According to a fourth aspect of the present invention, the above-mentioned objective is achieved by a vehicle comprising a control system according to any embodiment of the first aspect of the present invention and / or an electric power system according to any embodiment of the second aspect of the present invention.

[0040] The possible features and combinations of features disclosed herein are presented in the following form:

[0041] project:

[0042] 1. A control system for controlling an electric power system (1) for propelling a vehicle (100), wherein the electric power system comprises:

[0043] Traction voltage bus (2);

[0044] A plurality of batteries (3', 3") are electrically connected to each other via the traction voltage bus (2), wherein each battery is electrically connected to the traction voltage bus via at least one contactor (A, B); wherein the control system includes a corresponding battery control unit (BMU1, BMU2) for each of the plurality of batteries, wherein each battery control unit is configured to detect whether the battery experiences voltage drift during a relaxation period after a signal has been provided to disconnect at least one contactor of each battery, and when at least one battery is not subjected to voltage drift, the battery control unit for the at least one battery is further configured to issue a signal indicating that no voltage drift has been detected.

[0045] 2. The control system according to Project 1, wherein the control system further comprises:

[0046] A main electronic control unit (MECU) for controlling the plurality of batteries, wherein the MECU is communicatively connected to each of the battery control units, and wherein, after a signal has been provided to disconnect at least one contactor of each battery, the MECU is configured to provide a predetermined electrical interference to the traction voltage bus, and wherein each battery control unit is configured to detect the predetermined electrical interference, and when the predetermined electrical interference is detected by at least one of the battery control units, the at least one battery control unit is further configured to issue a signal indicating that the predetermined electrical interference has been detected.

[0047] 3. The control system according to any one of the preceding items 1, wherein the control system further comprises:

[0048] A main electronic control unit (MECU) for controlling the plurality of batteries, wherein the MECU is communicatively connected to each of the battery control units, and wherein the battery control unit for the at least one battery is further configured to send a signal to the MECU indicating that no voltage drift has been detected.

[0049] 4. The control system according to Project 2, wherein the main electronic control unit is further configured to identify whether at least one contactor of at least one battery in the batteries is welded before providing the predetermined electrical interference to the traction voltage bus.

[0050] 5. The control system according to any one of items 2 or 4, wherein the battery control unit for the at least one battery is further configured to send a signal to the main electronic control unit indicating that the predetermined electrical interference has been detected.

[0051] 6. The control system according to any one of items 2, 4 or 5, wherein the main electronic control unit is further configured to send a signal to each of the battery control units indicating that the predetermined electrical interference will be provided.

[0052] 7. The control system according to any one of items 2, 4, 5 or 6, wherein the predetermined electrical interference is at least one of a predetermined voltage level, a predetermined load, a load having a predetermined current level and a predetermined frequency level.

[0053] 8. An electric power system (1) for propelling a vehicle (100), wherein the electric power system comprises:

[0054] Traction voltage bus (2);

[0055] Multiple batteries (3', 3"), which are electrically connected to each other via the traction voltage bus (2), wherein each battery is electrically connected to the traction voltage bus via at least one contactor (A, B); and

[0056] The control system described in any of the aforementioned projects.

[0057] 9. A method for identifying at least one welded contactor in an electrical power system (1), wherein the electrical power system (1) is used to propel a vehicle, the electrical power system comprising: a traction voltage bus (2); a plurality of batteries (3', 3") electrically connectable to each other via the traction voltage bus (2), wherein each battery is electrically connectable to the traction voltage bus (2) via at least one contactor (A, B), and wherein each battery includes a corresponding battery control unit, wherein the method comprises:

[0058] For each battery, it is determined whether each battery experiences voltage drift during a relaxation period after a signal has been provided to disconnect at least one contactor of each battery, and when at least one battery is not experiencing voltage drift, a signal indicating that no voltage drift has occurred is issued from the battery control unit of the at least one battery.

[0059] 10. The method according to item 9, wherein the power system (1) further includes a main electronic control unit (MECU) for controlling the plurality of batteries, wherein the main electronic control unit is communicatively connected to a corresponding battery control unit for each of the batteries, wherein the method further includes:

[0060] After a signal has been provided to disconnect at least one contactor of each battery, a predetermined electrical interference is provided to the traction voltage bus by means of the main electronic control unit (S1).

[0061] For each battery, it is determined (S2) whether the predetermined electrical interference is detected, and when the predetermined electrical interference is detected by at least one battery control unit in the battery control unit, a signal indicating that the predetermined electrical interference has been detected is issued from the at least one battery control unit (S3).

[0062] 11. The method according to item 10 further includes: identifying when at least one contactor of at least one battery in the batteries is welded before providing the predetermined electrical interference to the traction voltage bus.

[0063] 12. The method according to any one of items 10 to 11, wherein a signal indicating that the predetermined electrical interference has been detected is sent from the at least one battery control unit to the main electronic control unit.

[0064] 13. The method according to any one of items 10 to 12, further comprising: issuing a signal to each of the battery control units in the battery control unit indicating that the predetermined electrical interference will be provided.

[0065] 14. The method according to any one of items 10 to 13, wherein the predetermined electrical interference is at least one of a predetermined voltage level, a predetermined load, a load having a predetermined current level, and a predetermined frequency level.

[0066] 15. A means of transport comprising a control system according to any one of items 1 to 7 and / or an electrical power system according to item 8.

[0067] Further advantages and advantageous features of the invention are disclosed in the description below and in the dependent claims. Attached Figure Description

[0068] The following is a detailed description of exemplary embodiments of the present invention, taken in conjunction with the accompanying drawings.

[0069] In the picture:

[0070] Figure 1This is a side view of a vehicle according to an exemplary embodiment of the present invention;

[0071] Figure 2 This is a schematic diagram of a control system and an electrical power system according to an exemplary embodiment of the present invention;

[0072] Figure 3 This is a schematic diagram of a battery and two contactors according to an exemplary embodiment of the present invention;

[0073] and

[0074] Figure 4 This is a flowchart of a method according to an exemplary embodiment of the present invention.

[0075] The accompanying diagram is schematic and not drawn to scale. Detailed Implementation

[0076] exist Figure 1 The figure shows a side view of a vehicle in the form of at least a partially electric truck 100. According to an exemplary embodiment of the invention, the vehicle 100 includes a control system 10 and an electrical power system 1. Although at least a partially electric truck 100 is shown in the figure, the invention is not limited to this type of vehicle, but can also be used in other vehicles such as buses, construction equipment, coaches, and marine vessels.

[0077] Especially refer to Figure 2 and Figure 3 The control system 10 and the power system 1 according to an exemplary embodiment of the present invention will be described.

[0078] The power system 1 includes a traction voltage bus 2 and multiple batteries 3', 3'' that can be electrically connected to each other via the traction voltage bus 2, wherein the power system 1 is intended to propel, for example... Figure 1 The vehicle 100 shown. Each battery 3', 3" is electrically connected to the traction voltage bus 2 via at least one contactor A, B, see, for example. Figure 3 In the illustrated embodiment, battery 3' can be electrically connected via two corresponding contactors A and B; contactor A is used for the positive terminal + of battery 3', and the other contactor B is used for the negative terminal - of battery 3'. In the illustrated example, contactor A is open while contactor B is closed, i.e., it may be welded. The same or similar configuration may also exist for another battery 3'". Therefore, Figure 2 An embodiment including two batteries 3', 3" is shown. However, it should be noted that the power system 1 may include more than two batteries. Here, the power system 1 is a high-voltage system, wherein each battery 3', 3" can be connected to each other via a so-called junction box 5. The junction box 5 can be defined as a connection center, etc., for electrically and / or communicatively connecting different electrical components of the power system 1. Additionally, in Figure 2In the illustrated embodiment, each battery 3', 3" is electrically connected to an electric traction motor 4, which is used to propel, for example, a vehicle 100. Therefore, batteries 3', 3" can be used to supply power to the traction motor 4, and / or the electric traction motor can be used as a generator to charge batteries 3, 3" . It should be noted that the electrical system 1 may include more than one electric traction motor, for example, two electric traction motors, or, for example, one electric traction motor for each driven wheel of the vehicle 100.

[0079] Figure 2 A control system 10 for controlling the power system 1 is further illustrated. The control system 10 includes corresponding battery control units BMU1 and BMU2 for each of the plurality of batteries 3', 3''. The control system 10 further includes a main electronic control unit (MECU) for controlling the plurality of batteries 3', 3'''. Figure 2 As shown by the dashed lines, the main electronic control unit (MECU) is communicatively connected to each of the battery control units (BMU1, BMU2). As illustrated, the MECU can preferably be an independent unit relative to batteries 3', 3" . Alternatively, as shown, each battery control unit (BMU1, BMU2) can be integrated with each corresponding battery 3', 3" .

[0080] After a signal has been provided to disconnect at least one contactor A, B in each of the batteries 3', 3"', the main electronic control unit (MECU) is configured to provide a predetermined electrical interference to the traction voltage bus 2. The predetermined electrical interference can be any type of predetermined electrical interference as defined herein, such as a predetermined voltage level. Furthermore, the signal to disconnect at least one contactor A, B in each of the batteries 3', 3"'' is preferably a signal provided by the main electronic control unit (MECU) to each battery control unit BMU1, BMU2.

[0081] Each battery control unit (BMU1, BMU2) is configured to detect a predetermined electrical interference, and when the predetermined electrical interference is detected by at least one of the battery control units (BMU1 and / or BMU2), the at least one battery control unit (BMU1, BMU2) is further configured to issue a signal indicating that the predetermined electrical interference has been detected. Preferably, the signal indicating that the predetermined electrical interference has been detected is issued to the main electronic control unit (MECU).

[0082] A signal indicating the detection of a predetermined electrical interference is an indication that at least one contactor A or B is still connected to the traction voltage bus 2, meaning it may have been welded. This suggests that a high voltage may still be present, which would be a dangerous situation for the user. By providing a control system as disclosed herein, it is possible to identify which battery(s) has at least one welded contactor.

[0083] Additionally or alternatively, each battery control unit BMU1, BMU2 can be configured to detect whether batteries 3', 3" experience voltage drift during the relaxation period following a signal that at least one contactor A, B has been disconnected from each battery 3', 3" . When at least one battery 3', 3" is not subject to voltage drift, the battery control units BMU1, BMU2 of the at least one battery 3', 3" are further configured to issue a signal indicating that no voltage drift was detected. Thus, this configuration can serve as a second indication that at least one contactor has been welded. In addition to the above method, using this method implies a redundant control system, thereby providing a more robust and reliable identification of at least one welded contactor.

[0084] Preferably, the battery control units BMU1 and BMU2 for at least one battery 3', 3" are further configured to send a signal to the main electronic control unit MECU indicating that no voltage drift has been detected.

[0085] The main electronic control unit (MECU) can be further configured to identify whether at least one contactor A, B of at least one battery 3', 3" is welded before providing a predetermined electrical interference to the traction voltage bus 2. This can be accomplished, for example, by detecting the presence of a voltage level in the traction voltage bus 2.

[0086] Additionally, the battery control units BMU1 and BMU2 for at least one battery 3', 3" can be further configured to send a signal to the main electronic control unit (MECU) indicating that a predetermined electrical interference has been detected. In this way, the MECU can determine which of the batteries 3', 3" has at least one welded contactor A, B.

[0087] The main electronic control unit (MECU) can be further configured to send a signal to each of the battery control units (BMU1, BMU2) indicating that a predetermined electrical interference will be provided. In this way, each battery control unit (BMU1, BMU2) can be prepared to determine when the predetermined electrical interference will be provided, which means further improved and more reliable identification of at least one welded contactor A, B.

[0088] The predetermined electrical interference can be at least one of a predetermined voltage level, a predetermined load, a load with a predetermined current level, and a predetermined frequency level.

[0089] Each control unit MECU, BMU1, BMU2 disclosed herein may include a computer program and / or computer-readable medium configured to perform certain steps of the methods disclosed herein. Control units MECU, BMU1, BMU2 may include microprocessors, microcontrollers, programmable digital signal processors, or other programmable devices. Control units MECU, BMU1, BMU2 may also or alternatively include application-specific integrated circuits, programmable gate arrays or programmable array logic, programmable logic devices, or digital signal processors. Where control units MECU, BMU1, BMU2 include programmable devices such as microprocessors, microcontrollers, or programmable digital signal processors described above, the processor may further include computer-executable code controlling the operation of said programmable device. Control units MECU, BMU1, BMU2 may include embedded hardware, sometimes with integrated software. Examples of physical relationships include components sharing a housing and mounted on one or more circuit boards. Control units MECU, BMU1, BMU2 may also include one or more sub-control units; that is, a corresponding control unit MECU, BMU1, BMU2 may be more than one individual control unit.

[0090] Figure 4 A flowchart of a method for identifying at least one welded contactor A, B of an electrical system 1, according to an exemplary embodiment of the present invention, wherein the electrical system 1 is used to propel a vehicle 100, is shown.

[0091] The method includes:

[0092] S1) After a signal has been provided to disconnect at least one contactor of each battery, a predetermined electrical interference is provided to the traction voltage bus 2 by means of the main electronic control unit MECU;

[0093] For each battery 3', 3''

[0094] S2) Determine whether a predetermined electrical interference has been detected, and when the predetermined electrical interference is detected by at least one battery control unit BMU1, BMU2,

[0095] S3) A signal indicating that a predetermined electrical interference has been detected is issued from the at least one battery control unit BMU1, BMU2.

[0096] Additionally or alternatively, the method may include:

[0097] For each battery 3', 3'", determine whether each battery has experienced voltage drift during the relaxation period after a signal has been given to disconnect at least one contactor A, B of each battery 3', 3'", and when at least one battery 3', 3' has not experienced voltage drift, issue a signal indicating that it has not experienced voltage drift from the battery control unit BMU1, BMU2 of the at least one battery 3', 3'".

[0098] The method may further include identifying when at least one contactor A, B of the batteries 3', 3" is welded before providing a predetermined electrical interference to the traction voltage bus 2.

[0099] At least one battery control unit (BMU1, BMU2) can send a signal to the main electronic control unit (MECU) indicating that a predetermined electrical interference has been detected.

[0100] The method may further include: sending a signal to each of the battery control units BMU1 and BMU2 indicating that a predetermined electrical interference will be provided.

[0101] It should be understood that the present invention is not limited to the embodiments described above and shown in the accompanying drawings; rather, those skilled in the art will recognize that many changes and modifications can be made within the scope of the appended claims.

Claims

1. A control system (10) for controlling an electric power system (1), wherein the electric power system (1) is used to propel a vehicle (100), wherein, The electrical power system (1) includes: Traction voltage bus (2); A plurality of batteries (3', 3") are electrically connected to each other via the traction voltage bus (2), and each battery (3', 3") is electrically connected to the traction voltage bus (2) via at least one contactor (A, B); wherein the control system (10) includes a corresponding battery control unit (BMU1, BMU2) for each of the plurality of batteries (3', 3"), and wherein the control system (10) further includes: A main electronic control unit (MECU) for controlling the plurality of batteries (3', 3"), wherein the MECU is communicatively connected to each of the battery control units (BMU1, BMU2), and wherein, after a signal has been provided to disconnect at least one contactor (A, B) of each battery (3', 3"), the MECU is configured to provide a predetermined electrical interference to the traction voltage bus (2), and wherein each battery control unit (BMU1, BMU2) is configured to detect the predetermined electrical interference, and when the predetermined electrical interference is detected by at least one of the battery control units (BMU1, BMU2), the at least one battery control unit (BMU1, BMU2) is further configured to issue a signal indicating that the predetermined electrical interference has been detected, wherein the signal indicating that the predetermined electrical interference has been detected is used to identify that the at least one contactor has been welded.

2. The control system (10) according to claim 1, wherein, Each battery control unit (BMU1, BMU2) is configured to detect whether the battery (3', 3") experiences voltage drift during a relaxation period after the signal has been provided to disconnect the at least one contactor of each battery (3', 3"), and when at least one battery (3', 3") is not subjected to voltage drift, the battery control unit (BMU1, BMU2) for the at least one battery (3', 3") is further configured to issue a signal indicating that no voltage drift has been detected.

3. The control system (10) according to claim 2, wherein, The battery control units (BMU1, BMU2) for the at least one battery (3', 3") are further configured to send a signal to the main electronic control unit (MECU) indicating that no voltage drift has been detected.

4. The control system (10) according to any one of the preceding claims, wherein, The main electronic control unit (MECU) is further configured to identify whether at least one contactor (A, B) of at least one of the batteries (3', 3") is welded before providing the predetermined electrical interference to the traction voltage bus (2).

5. The control system (10) according to any one of the preceding claims, wherein, The battery control unit (BMU1, BMU2) for the at least one battery (3', 3") is further configured to send a signal to the main electronic control unit (MECU) indicating that the predetermined electrical interference has been detected.

6. The control system (10) according to any one of the preceding claims, wherein, The main electronic control unit (MECU) is further configured to send a signal to each of the battery control units (BMU1, BMU2) instructing them to provide the predetermined electrical interference.

7. The control system (10) according to any one of the preceding claims, wherein, The predetermined electrical interference is at least one of a predetermined voltage level, a predetermined load, a load having a predetermined current level, and a predetermined frequency level.

8. An electric power system (1) for propelling a vehicle (100), wherein, The power system includes: Traction voltage bus (2); Multiple batteries (3', 3") are electrically connected to each other via the traction voltage bus (2), wherein each battery (3', 3") is electrically connected to the traction voltage bus (2) via at least one contactor (A, B); and The control system (10) according to any one of the preceding claims.

9. A method for identifying at least one welded contactor (A, B) in an electrical system (1), wherein the electrical system (1) is used to propel a vehicle (100), wherein, The power system (1) includes: a traction voltage bus (2); a plurality of batteries (3', 3") electrically connected to each other via the traction voltage bus (2), wherein each battery (3', 3") is electrically connected to the traction voltage bus (2) via at least one contactor (A, B); and a main electronic control unit (MECU) for controlling the plurality of batteries (3', 3"), wherein the main electronic control unit (MECU) is communicatively connected to a corresponding battery control unit (BMU1, BMU2) for each of the batteries (3', 3"), wherein the method includes: After a signal has been provided to disconnect at least one contactor (A, B) of each battery (3', 3"), a predetermined electrical interference is provided (S1) to the traction voltage bus (2) by means of the main electronic control unit (MECU); For each battery (3', 3"), it is determined (S2) whether the predetermined electrical interference is detected, and when the predetermined electrical interference is detected by at least one of the battery control units (BMU1, BMU2), a signal indicating the detection of the predetermined electrical interference is issued from the at least one battery control unit (BMU1, BMU2) (S3), wherein the signal indicating the detection of the predetermined electrical interference is used to identify that the at least one contactor has been welded.

10. The method according to claim 9, wherein, The method further includes: For each battery (3', 3"), it is determined whether each battery experiences voltage drift during the relaxation period after the signal of disconnecting at least one contactor (A, B) of each battery (3', 3") has been provided, and when at least one battery is not subjected to voltage drift, a signal indicating that no voltage drift has been subjected is issued from the battery control unit (BMU1, BMU2) of the at least one battery (3', 3") 11. The method according to any one of claims 9 to 10, further comprising: Before providing the predetermined electrical interference to the traction voltage bus (2), identify when at least one contactor (A, B) of at least one of the batteries (3', 3") is welded.

12. The method according to any one of claims 9 to 11, wherein, The at least one battery control unit (BMU1, BMU2) sends a signal to the main electronic control unit (MECU) indicating that the predetermined electrical interference has been detected.

13. The method according to any one of claims 9 to 12, further comprising: A signal is sent to each of the battery control units (BMU1, BMU2) instructing that the predetermined electrical interference will be provided.

14. The method according to any one of claims 9 to 13, wherein, The predetermined electrical interference is at least one of a predetermined voltage level, a predetermined load, a load having a predetermined current level, and a predetermined frequency level.

15. A means of transport (100) comprising a control system (10) according to any one of claims 1 to 7 and / or an electrical power system (1) according to claim 8.

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