METHOD FOR DISTRIBUTING A LIMITED ELECTRICAL POWER FROM AN ENERGY SOURCE

Description

[0001] The invention relates to a method for distributing a limited electrical power from an energy source to several electrical consumers of an orthopaedic system.

[0002] Orthopedic components include orthoses, prostheses, wheelchairs, data loggers, radio modules, feedback elements, electrical storage devices, or parts of orthoses, prostheses, or wheelchairs, such as prosthetic joints, prosthetic feet, tube adapters, prosthetic hands, prosthetic elbows, swivel adapters, prosthetic sockets, orthotic splints, orthotic joints, foot shells, and any sensors, storage devices, processors, or other data processing devices attached to them. A system consisting of several orthopedic components is a combination of such components into a single orthopedic unit that offers functionality beyond that of the individual components. For example, such a system could include a transfemoral prosthesis consisting of a femoral socket, a prosthetic knee joint, a lower leg tube, and a prosthetic foot.A below-knee prosthesis system consists of a lower leg socket and a prosthetic foot attached to it. Upper extremity prostheses, such as upper arm prostheses, can include a socket, an active elbow, a wrist, and a gripper. An orthotic system can, for example, be designed as a knee-ankle-foot orthosis.

[0003] Orthopedic components are often equipped with electrical and / or electronic devices to detect, for example, effective forces, spatial orientations, moments, or the relationships between components. Furthermore, based on sensor readings processed by a processor, the resistance of a damping device can be adjusted, or a motor drive can be activated or deactivated. The usage data of the orthopedic component can be analyzed, for example, to provide a basis for future adjustments. In addition, functional tests can be performed using connected testing equipment. Complete prosthetic or orthotic devices, such as computer-controlled arm prostheses or exoskeletons, are required for complex treatments.

[0004] In complex orthotic systems, each actuator or electrical component has its own associated energy storage device. Furthermore, coordinating, for example, a prosthetic knee joint with an actuated prosthetic ankle joint can be complex and may require independent adjustments. Even non-powered components may incorporate electronic devices, such as integrated sensors to monitor loads or angular positions. The modular design and the variety of prostheses or orthoses result in numerous possible combinations, which can increase the complexity of software optimization and power supply systems.

[0005] Particularly during stationary operation or when charging an energy storage device within the orthotic system, problems can arise. Due to the multitude of different device combinations and increasing energy and power demands, difficulties can occur in distributing the available electrical power to ensure consistent behavior across different orthotic systems. Especially during charging, the power supplied by the power adapter may be insufficient. Similar problems and difficulties, as described using an orthotic system as an example, also exist in other technical systems with electrical consumers.

[0006] US 2008 / 0052544 A1 describes a portable electronic device that incorporates a power management system. If the available electrical power is insufficient to supply all connected devices, one or more of the devices are shut down.

[0007] EP 3 176 896 A2 concerns a distribution system for electrical power, intended for use, for example, in an aircraft. The system has at least one supply line from which consumers can be disconnected.

[0008] US Patent 2003 / 0144779 A1 describes a power distribution system for a motor vehicle in which the total power requirement is divided into an essential amount and a specific amount. The system is designed to conserve electrical energy and / or fuel. If the power requirement exceeds a predetermined limit, certain non-essential consumers are switched off to reduce or limit consumption. Furthermore, depending on detected energy consumption exceeding a limit, it is possible to supply certain consumers with a reduced amount of energy to further conserve energy. This occurs not due to an insufficient amount of energy for optimal operation, but solely due to consumption exceeding a limit.

[0009] US Patent 2015 / 0346243 A1 describes, among other things, a device for determining the electrical power of a power source to which a large number of loads are connected. A resistor is provided for each load, the value of which corresponds to the power consumption of the respective device. The resistors are arranged in parallel. A measuring unit is set up to measure the combined resistance value of the parallel-connected resistors.

[0010] The object of the present invention is therefore to provide a method for distributing a limited electrical power, which prevents an overload of an energy source or power supply without jeopardizing the functionality of the system.

[0011] According to the invention, this problem is solved by a method with the features of the main claim. Advantageous embodiments and further developments of the invention are disclosed in the dependent claims, the description, and the figures.

[0012] The method for distributing a limited electrical power from a power source to multiple electrical consumers in an orthotic system involves first recording and / or encoding the available electrical power from the power source. A power balance among the electrical consumers is monitored by recording and / or encoding the electrical power drawn by each individual consumer. If it is determined that the available electrical power is insufficient to supply all consumers with the required power, the power drawn by the consumers is reduced. To achieve this, all consumers within the system are able to reduce their power consumption, allowing them to operate at a reduced power level, for example, to 40% or 50% of their specified maximum power.If the power drawn from the consumers is reduced, the entire orthotic system can continue to operate, albeit with reduced performance, without the risk of individual functions ceasing to function altogether. This method creates a uniform power distribution, in particular a uniform distribution of electrical energy to energy storage devices, making it possible to supply multiple electrical consumers with electrical power from a single energy source, or to supply or charge multiple electrical consumers or energy storage devices via a single power supply unit.By detecting and encoding the available electrical power from the energy source, it is possible to use various power supplies or energy sources of different power classes. This is because the available electrical power of the energy source is first detected, and the power drawn is adjusted accordingly. The power drawn from the energy source can be used to perform an action in or on the orthotic system, for example, to initiate an adjustment process via a motor. Alternatively or additionally, the drawn power can be used to charge one or more energy storage devices.The available power is encoded via digital signals between the energy source and at least one load. The loads are connected to a data bus, through which the power transferred to each load is transmitted to a control unit, and a power balance is calculated for all loads. The distribution of the available electrical power that can be distributed among all loads is calculated, for example, by a computer, to determine how much power can be allocated to each load. In a further development of the invention, if analog and digital encoding are used simultaneously, the digital encoding is prioritized because digital signals are easier to process in a control unit.

[0013] The available electrical power source can be encoded via its voltage characteristic or via a resistance value. The power source can be connected to the electrical load or energy storage device via a plug connector or a device connector. An additional line within the device connector allows the ratio of available power for charging or operating the electrical loads to the required power to be determined using an analog DC voltage. A voltage value for this DC voltage is defined, which signals to all connected electrical loads that the power source is fully utilized. Lower voltages indicate that the power consumption by the electrical loads must be reduced. Therefore, the voltage value of all electrical loads is monitored.

[0014] The maximum power required by a device can also be determined and encoded using electrical resistance. The maximum power consumption can be calculated from the electrical resistance and its maximum resistance value. The resistance can be calculated from the assumed power of a reference energy source, the resistance at the reference power, the required power, the available power, and the available voltage.

[0015] Advantageously, the reduction in power consumption is implemented uniformly across all consumers, so that all consumers reduce their power consumption equally, for example, by 50%. Alternatively, the reduction can be individualized depending on the needs of each consumer, for example, by prioritizing consumers that are particularly important for the system's operation and applying a smaller reduction in power consumption, or by reducing the charging current in individual or all consumers. The respective electrical consumers can be assigned an identifier or code that allows for a graduated reduction in power consumption among multiple consumers. Such coding can also be dynamic, for example, depending on detected load conditions, where different consumers may be prioritized or favored differently.

[0016] Encoding the available power via analog signals is a particularly simple and robust way to represent it. This encoding can be achieved using a pull-up resistor in a power supply or by encoding the maximum power draw using at least one pull-down resistor in at least one load. For this purpose, all devices include a pull-down resistor connected to ground via a control line. This pull-down resistor can be optionally deactivated, for example, if an energy storage device is not being charged via a power supply. Encoding the available power via a pull-up resistor involves a resistor in the power supply or energy source that runs in a control line from the energy source to the device connector. The available supply power can be set via this pull-up resistor.

[0017] The encoding of the available power can be transmitted via an optical medium or wirelessly, so that an adjustment of the extracted power can be made even with wireless coupling or independently of wireless coupling.

[0018] A further development of the invention provides that the available power is encoded in a connector that connects the device(s) to the power source, in particular a power supply or a battery. Via such a connector or connector receptacle, which is assigned to the orthotic system, it is possible to determine, independently of the power source (which may be a power supply or battery), what power is needed where and how much energy is supplied to which device at any given time. The connector or connector receptacle can be equipped with a resistor or a circuit board with a corresponding circuit to detect, encode, and, if necessary, reduce the available power, the power drawn, and the maximum power that can be drawn.

[0019] Each consumer, and in particular all consumers, can be assigned an identifier, whereby all consumers in the system with an identifier are identified and authenticated. Each identified and authenticated consumer can be granted a corresponding power release. Only after authentication is any power supplied from a power supply unit or energy source to the respective consumer. This ensures that only approved and authenticated electrical consumers can be used and powered within the orthotic system. This increases the safety for users of the orthotic system, as it ensures that only tested orthotic components are used or can be used as part of the system.

[0020] Consumers are defined as all components or assemblies that can absorb and store or consume energy from the energy source.

[0021] The encoding of the available electrical power preferably takes place in the energy source.

[0022] An embodiment of the invention is explained in more detail below with reference to the accompanying figures. These show: Figure 1 – a schematic representation of a system with one energy source and two consumers; Figure 2 – a variant of the Figure 1 with two optional energy sources; Figure 3 - a variant of the Figure 1 with a digital bus as a connection between two consumers; Figure 4 - a variant of the Figure 3with different power supplies; Figure 5 - an example dimensioning for a pull-up resistor in a power supply; Figure 6 - an example dimensioning for a pull-down resistor in loads; and Figure 7 - an example calculation for a power factor.

[0023] In the Figure 1A schematic diagram shows a power supply unit (PSU) as the sole energy source 1 for supplying several electrical loads 2 and 3. The PSU is connected to the first load 2 via a device connector 4. The second electrical load 3 is also connected to the PSU via a cable connection, which can also be implemented via a connector 5. The cable connection can also be implemented via the device connector 4 or another cable connection on the load 2. With a conventional connection of a PSU to several loads 2, 3, it is problematic to monitor the power PSU available for charging that can be supplied by the PSU. Due to space constraints, it may be necessary to provide only one connector 4 for a PSU in a system with several loads 2, 3.Space constraints exist, for example, in orthopedic systems such as orthoses, prostheses, or wheelchairs. Furthermore, due to a modular design, different device combinations with varying power consumers or energy storage systems may be required. This is necessary, for instance, to adapt the system to individual customer requirements or user needs by incorporating different power consumers. Additionally, further development or module replacement can lead to increased energy and power demands that were not anticipated in the original design. Similarly, various electrical power sources or power supplies with different power ratings may be available for use within a single system.A rigid determination of available or maximum output power is not possible with a conventional power supply and conventional loads supplied with a DC voltage via two conductors. It is desirable to provide a system that allows flexibility in the face of changes in both the hardware and the operating conditions. Therefore, according to the invention, in addition to ground and the conductor to the positive terminal, a control line 6 is provided in both the power supply 1 or energy supply 1 and in the loads 2, 3, via which power encoding can be performed. The control line 6, or power distribution line, is connected to all connector terminals 4, 5. The control line 6 indicates, via an analog DC voltage U EDC, the ratio of the power P SUP available for charging to the power P LOAD1, P LOAD2 currently required.The voltage value U EDC is therefore the quotient of the power available for charging P SUP and the power required at each consumer 2, 3, P LOAD .

[0024] To ensure continued functionality in the event of potential expansions or modifications to the system, such as additional or modified electrical loads, or combinations with other power supplies, it is advantageous to initially define a standard power supply or energy source with an associated pull-up resistor. All subsequent and future power supplies must be designed to be compatible with this standard power supply.

[0025] Furthermore, it is advantageous to define a voltage value for the DC voltage U EDC at which a full load of the respective connected power supply 1 is signaled for all connected devices. If lower voltages U EDC are detected, this means that the respective power consumption in the loads 2 and 3 must be reduced. The voltage value U EDC is measurable in all connected loads 2 and 3.

[0026] First, the supply voltage for the energy distribution control is defined with a standardized charging voltage. Should different charging voltages be required in the future, the power supply must be adjusted to the respective defined level.

[0027] In the Figure 2 is a variant of Figure 1The diagram shows two different power supplies 1, 1' with different pull-up resistors for different power ratings. Power supply 1 has pull-up resistor R SUP1, while the second power supply 1' has a different pull-up resistor R SUP1', which may be, for example, 50% higher than pull-up resistor R SUP.

[0028] In an exemplary embodiment according to Figure 3 The available power is encoded via digital signals using a signal bus, analogous to the embodiments according to the Figure 1 and 2However, only to one consumer 2. Additionally, a signal exchange takes place between consumers 2 and 3. The signal bus is installed between consumers 2 and 3. The first consumer 2 determines how much energy is distributed to the subsequent consumers 3 and manages the energy distribution within the system, for example, an orthosis or prosthesis. It uses the signal bus for this purpose. The pulldown resistors R LOAD in the consumers are identical in this embodiment.

[0029] In the Figure 4 Two power supplies 1, 1' are each connected to a terminal 4 of the respective load 2, 3. When both power supplies 1, 1' are connected, an internal comparison takes place between the loads 2, 3 to determine how the energy from the power supplies 1, 1' should be distributed to the respective loads.

[0030] In the Figure 5An exemplary dimensioning of the resistors as a function of the available power P SUP is shown. All power supplies 1, 1' must implement a pull-up resistor R SUP from the supply voltage U SUP, which is applied to control line 6, in order to encode the available electrical power P SUP. The required minimum value of the respective pull-up resistor is calculated from R sup min = R Ref P Ref P Sup , where PRef is the power rating of a reference power supply and RRef is the pull-up resistor at a reference power rating. A possible curve of the ratio of available power PSUP to the minimum pull-up resistor is shown in the diagram of the Figure 5 recorded.

[0031] All consumers 2 and 3 must implement a pulldown resistor R LOAD from control line 6 to ground to encode their respective maximum electrical power consumption. If the consumer is not currently receiving power, the pulldown resistor R LOAD can be deactivated, which is done by the switch in the Figure 1 and the Figure 2 as indicated.

[0032] The required maximum resistance value for the respective pulldown resistor R LOAD is calculated from R Ref P Ref P LOAD x U 100 % U SUP − U 100 % An example of the curve representing the relationship between the required power P LOAD and the pulldown R LOAD is shown in the diagram of the Figure 6 shown.

[0033] All loads 2 and 3 must evaluate the control voltage U EDC. If the reference voltage U 100% is not reached, the available electrical power P SUP is less than the required power, so the power consumed by loads 2 and 3 must be reduced. The available relative power k is calculated as the quotient of the available power P SUP divided by the sum of the required powers P LOAD. If the relative power is greater than 1, sufficient power is available from power supply 1 or power supplies 1. If the value for the available relative power k is less than 1, insufficient power is available. A load may draw a maximum of its proportionally available power P max, which is calculated as the product of the available relative power k and the required power P LOAD. The ratio of the measurement voltage U EDC to the power factor k is given in the Figure 7As shown in the calculation example, the threshold value for the measuring voltage U EDC is 2.5V to ensure that all consumers 2, 3 are supplied with sufficient energy.

[0034] A status indicator showing the available power can be attached to each power supply unit (1, 1'). This can be coded, for example, in three levels corresponding to power factors. Above a power factor of 1, a green indicator can signal that sufficient power is available; below a power factor of 0.5, a red indicator signals insufficient power; and in between, for example, a yellow indicator can signal that the charging process will be extended.

Claims

1. A method for distributing a limited amount of electrical power from an energy source (1, 1') among a plurality of loads (2, 3) of an orthopaedic system, having the following steps: a. measuring and / or coding the available electrical power (PSUP) of the energy source (1, 1'), b. monitoring a power balance of the loads (2, 3) by measuring and / or coding the drawn power in the individual loads (2, 3), characterized by c. reducing the drawn power in the loads (2, 3) to operate the loads (2,3) at reduced power, if the available power (PSUP) is not sufficient to supply all loads (2, 3) with the required power, wherein the loads (2, 3) are connected to a data bus and a division of the available electrical power (PSUP) among all loads (2, 3) is calculated and wherein the available power (PSUP) is coded via digital signals between the energy source (1, 1') and the at least one load (2, 3).

2. The method as claimed in claim 1, characterized in that the available electrical power (PSUP) of the energy source (1, 1') is coded via its voltage characteristic, a resistance (RLOAD, RSUP) or an analog voltage signal (UEDC).

3. The method as claimed in claim 1 or 2, characterized in that the maximum required power (PLOAD) of a load (2, 3) is determined and coded via an electrical resistance (RLOAD).

4. The method as claimed in one of the preceding claims, characterized in that the reduction is performed uniformly in all loads (2, 3) or is adapted individually to the respective load (2, 3) depending on the requirement.

5. The method as claimed in one of the preceding claims, characterized in that the available power (PSUP) is coded via analog signals.

6. The method as claimed in claim 5, characterized in that the available power (PSUP) is coded via a pull-up resistance (RSUP) in a power supply unit (1, 1') and the maximum power to be drawn is coded via at least one pull-down resistance (RLOAD) in at least one load (2, 3).

7. The method as claimed in claim 1, characterized in that, if an analog and digital coding are applied, the digital coding is prioritized.

8. The method as claimed in one of the preceding claims, characterized in that the available power (PSUP) is coded via an optical medium or wirelessly.

9. The method as claimed in one of the preceding claims, characterized in that the available power (PSUP) is coded in a plug-in connector (4, 5) which connects the load or loads (2, 3) to the energy source (1, 1').

10. The method as claimed in one of the preceding claims, characterized in that an identifier is assigned in each case to the loads (2, 3) and all loads (2, 3) of the system provided with an identifier are identified and authenticated.

11. The method as claimed in claim 10, characterized in that each identified and authenticated load (2, 3) is granted a power release which is assigned to it.

12. The method as claimed in one of the preceding claims, characterized in that the available power (PSUP) is coded in the energy source (1, 1').