System and Method for Allocating Propulsion Load Power Extracted from High-Energy Batteries and High-Power Batteries

Abstract

To provide a system and method for allocating load power drawn from multiple batteries for powering propulsion of a vehicle.SOLUTION: A battery system 11 includes: a high-energy battery 18a and a high-power battery 18b respectively designed for optimal production of DC power during high-specific-energy and high-specific-power propulsion; and battery health management systems configured to monitor the state of charge and the state of health of the batteries and generate battery status signals. The system further includes a propulsion load configured to produce propulsion force using power converted from power generated by at least one of the batteries, and a system controller 12 configured to allocate load power drawn from the high-energy and high-power batteries for use by the propulsion load in accordance with a propulsion phase of the vehicle and the battery status.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure generally relates to hybrid electric systems and fully electric systems that rely on battery technology to supply power to connected loads such as propulsion loads for aircraft or other vehicles.

Background Art

[0002] As used herein, the term "propulsion load" means an electric propulsion device that consumes (active) power. This is in contrast to a power source such as a battery that generates power. As used herein, the term "load power" refers to the power drawn from a battery and consumed by an electric propulsion device. As used herein, the term "connected" in the context of a battery means that the battery is coupled to supply load power, and the term "disconnected" means that the battery is decoupled so as not to supply load power.

[0003] Some aircraft (hereinafter referred to as "electric aircraft" in this specification) have an electric drive propulsion system. In such aircraft, an electric motor converts electrical energy into mechanical force for use by the propulsion system. For example, the electric motor may rotate one or more propellers of the aircraft to provide thrust. Electric aircraft can take various forms. For example, an electric aircraft may be an airplane, a rotary-wing aircraft, a helicopter, a quadcopter, an unmanned aerial vehicle, or some other suitable type of aircraft.

[0004] When an electric motor is used for propulsion of an aircraft or other vehicle, electrical energy is supplied by a power source. For example, the electrical energy may be supplied by a DC power source including a "battery" connected between a positive and negative high-voltage direct current (HVDC) busbar. As used herein, the term "high voltage" in the context of direct current means 270V DCThis refers to any DC voltage greater than [a certain value]. The battery supplies power to the electric motor. The electric motor is configured to convert electricity into mechanical power for use in the propulsion systems of aircraft or other vehicles.

[0005] Some electric propulsion vehicles (e.g., hybrid electric aircraft) have a hybrid power architecture. In this case, at least two different types of power sources are connected in parallel to the propulsion load. The electrical energy sources will often have various electrical characteristics. For example, the electrical energy sources may be a battery and a generator driven by an internal combustion engine or a gas turbine engine.

[0006] In future hybrid and all-electric systems that rely on advanced battery technology, one of the limiting factors is the specific energy of the battery. (As used herein, the term “specific energy” means the battery energy capacity per unit weight.) While some battery cell manufacturers have developed technologies that enable specific energies exceeding 350 Wh / kg, such technologies tend to have performance limitations, such as high specific power capacity. (As used herein, “specific power” refers to the load capacity per unit weight in watts.) Batteries are typically sized for both energy and power. This results in larger and heavier batteries. If the power demand is greater than the capacity of the cell technology, designers must either increase the battery size to meet the requirements or use a different cell technology that has better power capacity but lower specific energy.

[0007] Future hybrid and all-electric systems, which rely on advanced battery technology, will require lightweight and high-performance batteries. [Overview of the project]

[0008] The subject matter disclosed in some detail below concerns a system and method for allocating load power drawn from a battery system comprising multiple batteries of various designs to power the propulsion of a transport. The design of the individual batteries is optimized to minimize the overall battery weight while meeting the power demands of various operating modes. According to one embodiment, the battery system includes one battery and another battery. One battery (hereinafter referred to as the "HE battery") is designed for optimal performance during propulsion at high specific energy. The other battery (hereinafter referred to as the "HP battery") is designed for optimal performance during propulsion at high specific power. The entire system further includes a system controller configured to enable the battery system to have optimal performance and reduced weight while avoiding the battery system becoming large to handle peak loads.

[0009] More specifically, the system controller is configured to allocate load power drawn from the HE and HP batteries, and then to control multiple DC-AC converters that supply AC power to their respective AC-powered devices (e.g., electric propulsion). In the case of a transport vehicle, the system controller is configured to adjust the allocation of load power according to the changing power demands during the transport vehicle's propulsion. In at least some cases, the load power drawn by the devices is allocated to the HE and HP batteries according to the mode of operation of the transport vehicle (e.g., the flight phase of an aircraft).

[0010] According to one embodiment, the system controller is configured to determine the amount of DC power supplied by the HE battery and the amount of DC power supplied by the HP battery in a particular operating mode. The system controller receives information indicating the system's power demand and then determines how to allocate the load power drawn from the HE and HP batteries to meet that power demand. To make such a decision, the system controller needs to know the status and health of the HE and HP batteries (e.g., charge state, lifespan, impedance, power capacity, temperature, etc.). Each of the HE and HP batteries is associated with its own dedicated State of Charge (SOC) / State of Health (SOH) monitoring / management system (hereinafter referred to as the "SOC / SOH manager") connected to the system controller. The SOC / SOH manager transmits battery status signals to the system controller and receives command signals from the system controller. The respective load power drawn from the HE and HP during various phases of the mission is allocated by the system controller. The system controller controls the respective DC voltage conversion systems that receive high-voltage DC power from the HE and HP batteries. The resulting DC power can then be converted to AC power for use by one or more AC-powered devices (e.g., AC motors).

[0011] According to one embodiment presented, each of the HE and HP batteries may consist of a battery pack. As used herein, the term “battery pack” means one or more battery modules connected in series, parallel, or a combination thereof, wherein each battery module consists of multiple battery cells. For example, the HE battery may be a first battery pack managed by a first SOC / SOH manager, while the HP battery may be a second battery pack managed by a second SOC / SOH manager. The SOC / SOH managers may be the respective processors or computers or the respective modules hosted by the computers. In any case, means are provided for communicating SOC and SOH data acquired by the SOC / SOH managers to a system controller. The system controller and the SOC / SOH managers may be components of a battery health management system. The system may include other components configured to perform various disconnection and protection functions in response to the occurrence of a fault (e.g., a short circuit) in the battery pack.

[0012] Various embodiments of systems and methods for allocating load power drawn from HE and HP batteries to power the propulsion of a transport vehicle will be described in some detail below, one or more of these embodiments may be characterized by one or more of the following aspects.

[0013] One aspect of the subject matter disclosed in detail below is a system for allocating load power drawn from a battery system to power the propulsion of a transport vehicle. The system comprises a high-energy battery designed for optimal generation of DC power during propulsion at high specific energy, a high-energy battery health management system configured to monitor the charge and health status of the high-energy battery and generate a first battery status signal representing the charge and health status of the high-energy battery, a high-power battery designed for optimal generation of DC power during propulsion at high specific power, a high-power battery health management system configured to monitor the charge and health status of the high-power battery and generate a second battery status signal representing the charge and health status of the high-power battery, a propulsion load configured to generate propulsion using power converted from power generated by at least one of the high-energy battery and the high-power battery, and a system controller configured to receive the first and second battery status signals and then allocate the load power drawn from the high-energy battery and the high-power battery for use by the propulsion load, according to the propulsion phase of the transporter and the status of the high-energy battery and the high-power battery as represented by the first and second battery status signals.

[0014] According to one embodiment of the system described in the preceding paragraph, the transport body is an aircraft, the propulsion phase is the flight phase, and the system controller (1) allocates load power drawn from the high-energy battery and the high-power battery during high-demand periods such as the aircraft's high-power phase (including takeoff, climb, and second climb), and (2) allocates first load power drawn from the high-energy battery during low-demand periods such as the aircraft's cruising phase (including cruising and hovering) (without allocating any load power to the high-power battery), and allocates second load power drawn from the high-energy battery to charging the high-power battery.

[0015] Another aspect of the subject disclosed in detail below is a computer-implemented method for allocating load power drawn from a battery system to power the propulsion of a vehicle. The battery system includes a high-energy battery designed for optimal generation of DC power during propulsion at high specific energy, and a high-power battery designed for optimal generation of DC power during propulsion at high specific power. The method includes (a) monitoring the charge and health status of the high-energy battery, (b) generating a first battery status signal representing the charge and health status of the high-energy battery, (c) monitoring the charge and health status of the high-power battery, (d) generating a second battery status signal representing the charge and health status of the high-power battery, and (e) allocating load power drawn from the high-energy battery and the high-power battery in accordance with the propulsion phase of the vehicle and the status of the high-energy battery and the high-power battery as represented by the first and second battery status signals.

[0016] A further aspect of the subject disclosed in detail below is a system for allocating load power drawn from a battery system to power the propulsion of a transport. The system comprises a DC power supply bus, a first DC voltage converter connected to the DC power supply bus, a high-energy battery connected to the first DC voltage converter, the high-energy battery health management system configured to monitor the charge state and health state of the high-energy battery and generate a first battery status signal representing the charge state and health state of the high-energy battery, a second DC voltage converter connected to the DC power supply bus, a high-power battery connected to the second DC voltage converter, the high-power battery designed for optimal generation of DC power during propulsion at high specific energy, and the charge state and health state of the high-power battery A high-power battery health management system configured to monitor the condition and generate a second battery status signal representing the charge and health status of the high-power battery, and a system controller that receives the first battery status signal and the second battery status signal and sends commands to the first DC voltage conversion system and the second DC voltage conversion system, the first DC voltage conversion system and the second DC voltage conversion system comprising the system controller which allocates load power drawn from the high-energy battery and the high-power battery according to the propulsion phase of the transport body and the status of the high-energy battery and the high-power battery represented by the first battery status signal and the second battery status signal.According to some embodiments, the system further comprises a first DC-AC converter connected to a DC power supply bus, a first propulsion load connected to receive AC power from the first DC-AC converter, a second DC-AC converter connected to a DC power supply bus, and a second propulsion load connected to receive AC power from the second DC-AC converter, wherein a system controller is further configured to send commands to the first DC-AC converter and the second DC-AC converter to control the amount and frequency of the respective AC power supplied to the first and second propulsion loads.

[0017] Other aspects of systems and methods for allocating load power drawn from HE and HP batteries to power the propulsion of a transport vehicle are disclosed below.

[0018] The features, functions, and advantages described above may be realized individually in various embodiments, or combined in yet another embodiment. Various embodiments are described below with reference to the drawings to illustrate the aforementioned embodiments and other embodiments. In the drawings, rectangles drawn with solid lines indicate activated components, while rectangles drawn with dashed lines indicate deactivated components. [Brief explanation of the drawing]

[0019] [Figure 1] This is a block diagram identifying the components of a typical aerospace electric propulsion system architecture with a single thruster. [Figure 2] Block diagram shows an architecture for a system designed to allocate load power drawn from a battery system according to one embodiment. [Figure 3] This is a block diagram identifying the components of a system for allocating load power drawn from a high-energy battery and a high-output battery to power the propulsion of an aircraft, according to one embodiment. [Figure 4]A flowchart showing the power flow during the takeoff or ascent phase of an aircraft's flight according to the presented embodiment of the system depicted in FIG. 3. [Figure 5] A flowchart showing the power flow during the cruise phase of an aircraft's flight according to the presented embodiment of the system depicted in FIG. 3. [Figure 6] A flowchart showing the power flow during the descent / deceleration phase of an aircraft's flight according to the presented embodiment of the system depicted in FIG. 3. [[ID= eight]] [Figure 7] A flowchart showing the power flow while the system depicted in FIG. 3 is operating in the fault-tolerant mode. [Figure 8] A flowchart showing the power flow while the system depicted in FIG. 3 is operating in the ground charging mode.

Mode for Carrying Out the Invention

[0020] Refer to the figures below. Similar elements in different figures are assigned the same reference numerals.

[0021] Exemplary embodiments of a system and method for allocating the load power drawn from HE and HP batteries to power the propulsion of a vehicle are described in somewhat more detail below. However, not all features of the actual embodiments are described herein. Those skilled in the art should understand that in the development of such embodiments, in order to achieve the specific objectives of the developer, such as compliance with system-related constraints that vary depending on each embodiment and compliance with business-related constraints, it is necessary to make judgments specific to a number of embodiments. Furthermore, although the effort for such development is complex and time-consuming, it should be understood by those skilled in the art who have the advantages of this disclosure that it is a matter to be tackled.

[0022] For illustrative purposes, a system for allocating the load power drawn from a plurality of batteries to power the propulsion of an electric aircraft is described below. However, the techniques presented herein are not limited to aircraft applications and are also applicable to the propulsion of other types of electric vehicles such as automobiles, industrial vehicles, and trains.

[0023] FIG. 1 is a block diagram identifying the components of a typical aerospace electric propulsion system architecture having a single thruster. The thruster is partially formed by a motor controller 24 that converts DC power to AC power, an AC motor 28 that receives AC power from the motor controller 24, and a propeller 30 that is driven to rotate by the AC motor 28. The propeller 30 includes a propeller shaft (not shown in FIG. 1) and a plurality of propeller blades (not shown in FIG. 1) that are mechanically coupled to the output shaft of the AC motor 28 (not shown in FIG. 1).

[0024] In some embodiments, the motor controller 24 has three channels for supplying AC current to each set of stator windings within the AC motor 28. Each channel of the motor controller 24 includes a corresponding inverter (not shown in FIG. 1) having a power switch and a corresponding inverter controller (not shown in FIG. 1) (collectively referred to herein as an "inverter / controller"). The inverter controller controls the state of the power switch. The inverter is connected to the windings of the AC motor 28 (not shown in FIG. 1). The operation of the inverter is controlled by the inverter controller. The inverter controller transmits a switch control signal to the inverter via a switch signal line (not shown in FIG. 1) and receives a switch state signal from the inverter. The inverter converts DC power to polyphase AC power for the AC motor 28.

[0025] In the system depicted in Figure 1, the HVDC power source is battery 18. For example, battery 18 may include multiple battery modules (not shown in Figure 1) configured to form a battery pack. Each battery module is a parallel / series configuration of individual cells. Each battery module may be monitored by an associated module monitoring unit (not shown in Figure 1). Each module monitoring unit includes sensors for independently measuring virtual cell voltage and individual cell temperature. The module monitoring unit also includes a balancing circuit.

[0026] The system depicted in Figure 1 further includes a DC voltage conversion system 20 configured to receive low-voltage DC power from a battery 18 and convert that low-voltage DC power into high-voltage DC power. The DC voltage conversion system 20 comprises a converter controller and a voltage converter (collectively referred to herein as the "converter / controller"). The converter controller generates control signals according to specific switching modulation algorithms, such as pulse-width modulation, phase-shift modulation, and interleaved modulation, or a combination of two or three of these. The voltage converter, controlled by the converter controller using one of the aforementioned specific modulation methods, converts the input current of the input voltage into the output current of the output voltage. Meanwhile, specific electrical performance requirements, such as improved efficiency, reduced current ripple, and minimized noise, are achieved.

[0027] The system depicted in Figure 1 further includes a DC power supply bus 22 (labeled "DC bus 22" in Figure 1) connected to receive high-voltage DC power from the DC voltage conversion system 20. The motor controller 24 then receives high-voltage DC power from the DC power supply bus 22.

[0028] The system depicted in Figure 1 also includes a battery health management system 14. The operation of the battery 18 is managed by the battery health management system 14. Each module monitoring unit built into the battery 18 communicates sensor data representing virtual cell voltage and individual cell temperature to the battery health management system 14. The battery health management system 14 may be configured to ensure redundant protection, fail-safe operation, and selective shutdown of the battery string. The battery health management system 14 may be further configured to provide battery overcharge protection or to prevent other events or combinations of events that could lead to thermal runaway of the battery. More specifically, the switching state of a contactor (not shown in Figure 1) is controlled by the battery health management system 14 so that it opens in response to the detection of a fault condition (e.g., a short circuit).

[0029] As shown in Figure 1, the system further includes a system controller 12. The system controller 12 interacts with the battery health management system 14. The inverter controller of the motor controller 24 (not shown in Figure 1) is communicatively coupled to receive control signals from the system controller 12 and to send feedback signals to the system controller 12. The system controller 12 performs the role of commanding and coordinating all inverter controllers. The system controller 12 also receives thrust and pitch inputs from the pilot via the thrust control lever and the pitch control lever (neither of which are shown in Figure 1). Based on information from the sensors and pilot inputs, the system controller 12 commands and coordinates the operation of the inverter controllers.

[0030] Instead of an electric propulsion system having a single battery 18 as depicted in Figure 1, this disclosure presents an improved electric propulsion system including integrated HE and HP batteries (e.g., battery packs). The integrated HE and HP batteries are designed to minimize battery weight while meeting the power demands of various operating modes of the electric propulsion system. HE batteries are designed for optimal generation of DC power during high specific energy propulsion, and HP batteries are designed for optimal generation of DC power during high specific power propulsion. High specific energy propulsion is typically associated with relatively low power demands, where high specific energy batteries offer the advantage of low weight. HP batteries have relatively low specific energy (~200 Wh / kg) and allow discharge rates greater than 5C, while HE batteries have relatively high specific energy (~400 Wh / kg) and typically allow discharge rates of 1C to maintain healthy battery operation. (In describing batteries, discharge current is often expressed relative to the C rate to normalize with respect to battery capacity.) The C rate is a measure of the rate at which a battery is discharged relative to its maximum capacity. Therefore, incorporating HP batteries is particularly beneficial in high-power demand modes (e.g., during aircraft takeoff and climb). HE and HP batteries are controlled individually but coordinated by the system controller. The battery designs presented herein ensure that the respective loads drawn from the HE and HP batteries are appropriately allocated in response to load requests and system controller commands.

[0031] Figure 2 is a block diagram showing an architecture for a system designed to allocate load power drawn from an HE battery and an HP battery (not shown) by an aircraft propulsion system (not shown). The system depicted in Figure 2 includes an HE battery health management system 14a configured to monitor the charge and health status of the HE battery and generate a first battery status signal 32a representing the charge and health status of the HE battery, and an HP battery health management system 14b configured to monitor the charge and health status of the HP battery and generate a second battery status signal 32b representing the charge and health status of the HP battery.

[0032] Each battery health management system includes sensors to monitor various characteristics of each battery cell, such as cell voltage, cell current, and cell temperature. The voltage, current, and temperature sensors are connected to their respective analog-to-digital converters. Each analog-to-digital converter acquires battery data in analog form from the various sensors, converts that battery data into a digital output, and then sends the digital output to a processor unit (e.g., a SOC / SOH manager). The processor unit may be a processor, a microcontroller, multiple processors, a multicore processor, and / or a microprocessor. The processor unit processes the sensor data and derives battery performance information, such as battery voltage, battery current, battery temperature, charge state, and health state for each battery unit. At a given time, a battery has its maximum energy storage potential. The maximum energy storage potential can change over time. The charge state is a comparison of the amount of energy stored in the battery to the maximum amount of energy the battery can currently store. The health state is the health of the battery, determined by detecting, predicting, and isolating various anomalies. Various abnormalities may include, but are not limited to, a decrease in capacity, unusual temperature behavior, charge loss, changes in internal resistance, pressure anomalies, and dimensional changes. The health status is a comparison of the aforementioned parameters to their values ​​when the battery was new.

[0033] The system further includes a system controller 12 connected to the flight computer 10 and to the HE and HP battery health management systems 14a and 14b. The flight computer 10 receives mission inputs such as destination, flight conditions, space constraints, and reserve fuel, and then outputs flight data related to propulsion control to the system controller 12. The arrows labeled "Flight Control Input" in Figure 2 represent the communication of that flight data to the system controller 12. The system controller 12 also receives first and second battery status signals 32a and 32b from the HE and HP battery health management systems 14a and 14b. The system controller 12 is configured to allocate load power drawn from the HE and HP batteries for use with propulsion loads, depending on the aircraft's flight phase (represented by the flight control inputs) and the status of the HE and HP batteries (represented by the battery status signals). The system controller 12 allocates the drawn loads by transmitting control signals 34 to the respective DC voltage conversion systems.

[0034] Figure 3 is a block diagram identifying the components of a system for allocating load power drawn from a battery system 11 to a DC power supply bus 22 to power the propulsion of a transport vehicle, according to one embodiment. The operation of the entire system is controlled by a system controller 12. The system controller 12 is communicatively coupled to various components of the battery system 11.

[0035] The battery system 11 includes HE and HP batteries 18a and 18b. The HE and HP batteries 18a and 18b are connected in parallel with the DC power supply bus 22 to provide a fault tolerance. The HE battery 18a is designed for optimal generation of DC power when propelling at high specific energy, and the HP battery 18b is designed for optimal generation of DC power when propelling at high specific power. The battery system 11 further includes a DC voltage converter / controller 20a of a DC voltage conversion system connected to the HE battery 18a and connected to the DC power supply bus 22, and a DC voltage converter / controller 20b of a second DC voltage conversion system connected to the HP battery 18b and connected to the DC power supply bus 22. Each DC voltage converter / controller sends a feedback signal to the system controller 12 and receives a command signal from the system controller 12 to execute a specific charge or discharge control algorithm at appropriate current, voltage, and power levels. The batteries connected to each converter / controller provide a stable, tight, narrow-bandwidth DC bus voltage. This allows for weight reduction of supply, protection, and load devices.

[0036] The battery system 11 also includes a first SOC / SOH manager 16a configured to monitor the charge and health status of the HE battery 18a and generate a battery status status signal representing the charge and health status of the HE battery 18a, and a second SOC / SOH manager 16b configured to monitor the charge and health status of the HP battery 18b and generate a battery status status signal representing the charge and health status of the HP battery 18b. More specifically, the SOH / SOH managers 16a and 16b transmit battery status signals to the system controller 12 (described below) and receive command signals from the system controller 12.

[0037] The system controller 12 is configured to process battery status signals received from SOH / SOH managers 16a and 16b, and then send commands to DC voltage converters / controllers 20a and 20b. These commands allocate load power drawn from HE and HP batteries 18a and 18b. The system controller 12 determines the optimal load power allocation based at least on the aircraft's propulsion phase (as required by flight control inputs) and the status of HE and HP batteries 18a and 18b, as represented by the first and second battery status signals. Other data may also be factors in the load allocation calculation.

[0038] The system depicted in Figure 3 further includes a first inverter / controller 24a for the first motor controller and a second inverter / controller 24b for the second motor controller. Each inverter / controller is configured to perform DC-AC conversion at a required frequency. This frequency controls the shaft speed of the motor-propulsion assembly of the propulsion load. Both motor controllers receive DC power from the DC power supply bus 22. The first propulsion load is connected to receive AC power from the first inverter / controller 24a. The second propulsion load is connected to receive AC power from the second inverter / controller 24b. The system controller 12 is further configured to send commands to the inverter controllers to control the magnitude and frequency of the AC power output. More specifically, each inverter / controller receives a command signal from the system controller 12, sends a feedback signal to the system controller 12, and executes a specific DC-AC conversion algorithm to provide AC power at the appropriate amplitude and frequency. The frequency of the AC power determines the motor shaft speed. The required propulsion speed is determined by the system controller 12.

[0039] On the load side, the exemplary system depicted in Figure 3 includes a first propulsion load 26a connected to receive AC power from inverter / controller 24a, a second propulsion load 26b connected to receive AC power from inverter / controller 24b, a non-propulsion load 6 connected to receive DC power from DC power supply bus 22, and a charging station 8 also connected to DC power supply bus 22 for charging batteries in charge mode. The non-propulsion load 6 may be a composite load that includes multiple individual loads. All loads are commanded by the system controller 12.

[0040] The system controller 12 is configured to optimize the allocation of load power when a specific mission profile is received. For example, a typical mission profile consists of a cycle of operating modes (flight phases) such as taxiing, takeoff, climb, cruise, descent / deceleration, landing, taxiing, and reserve. In this case, the reserve phase requires that the remaining battery energy is sufficient for a second climb and hovering over a specific period before landing.

[0041] Power demand for the cruising phase is considerably lower than that for the takeoff or climb phase, typically less than half the power required for the takeoff / climb phase. Power demand for other modes, such as descent, landing, and taxiing, is even lower. Therefore, the system controller 12 is configured to control the DC voltage converter / controller so that load power for the cruising, descent, landing, and taxiing phases is drawn solely from the HE battery, or optimally allocated between the HE battery and HP battery as needed.

[0042] Generally, two flight phases demand most of the energy stored from the battery system: (1) the high-power phase, including takeoff, climb, and second climb, and (2) the cruising phase, including cruising and hovering. Low-power phases, such as descent, landing, taxiing, and waiting for control tower instructions, are considered to fall within the scope of the cruising phase, adding an appropriate percentage of overhead. Overhead can be considered when the actual mission profile is given. Therefore, the high-power and cruising phases are the primary factors influencing battery size determination during battery system design.

[0043] Figure 4 is a flowchart identifying the stages of power flow during takeoff or climb mode according to one presented embodiment of the system depicted in Figure 3. The arrows exiting the DC voltage converter / controller 20a represent the power flow from the HE battery 18a to the DC power supply bus 22, and the arrows exiting the DC voltage converter / controller 20b represent the power flow from the HP battery 18b to the DC power supply bus 22. Load power demand is highest during takeoff and climb. The battery system 11 is activated and discharges the power generated by the HE and HP batteries 18a and 18b, respectively, to the DC power supply bus 22. However, the HP battery 18b provides a larger proportion of the total power than the proportion provided by the HE battery 18a. The specific allocation of load power drawn from the HE and HP batteries 18a and 18b is determined by the system controller 12 and implemented by the two sets of DC converters / controllers 20a and 20b.

[0044] The functions of each voltage converter / controller 20a and 20b include: (1) receiving command signals from the system controller 12 regarding battery power output requests; (2) sending power supply status back to the system controller 12; and (3) providing a control and power conversion interface with the battery associated with the DC power supply bus 22 during charging and discharging. In any operating mode (e.g., during the ascent phase), the system controller 12 (or the flight control system) sends a power demand signal to each DC voltage converter / controller to supply a specific amount of energy to the DC power supply bus 22. Thus, the load power allocation between the HE and HP batteries 18a and 18b is determined by the system controller 12. Each DC voltage power converter / controller then executes a specific control algorithm, thereby supplying the required amount of power to the DC power supply bus 22 accordingly.

[0045] Figure 5 is a flowchart showing the power flow during the cruising phase of an aircraft flight according to one presented embodiment of the system depicted in Figure 3. During cruising, the load power demand is significantly reduced. The HE battery 18a supplies power to all loads under the control of the system controller 12 (as indicated by the arrow pointing from the HE battery 18a to the DC power supply bus 22). Meanwhile, the HE battery 18a also charges the HP battery 18b under the control of the system controller 12 (as indicated by the arrow pointing from the DC power supply bus 22 to the HP battery 18b). Depending on the specific design, the HP battery 18b may hold enough energy to be deactivated during the cruising phase.

[0046] Figure 6 is a flowchart showing the power flow during the descent / deceleration phase of an aircraft's flight, according to one presented embodiment of the system depicted in Figure 3. In this case, regeneration is possible. During the descent phase, the aircraft uses the form of regenerated power. In this case, each AC motor becomes a generator rotated by the propeller, allowing the batteries to be partially recharged using the free energy provided by gravity and aerodynamic resistance. Thus, one or both batteries can collect recharge energy and operate in charge mode. The power flow from inverters / controllers 24a and 24b to HE and HP batteries 18a and 18b is shown in Figure 6 by arrows pointing to (a) the power supply bus 22 from inverter / controller 24a, (b) the DC power supply bus 22 from DC voltage converter / controller 20a, (c) the DC voltage converter / controller 20a from HE battery 18a, (d) the DC power supply bus 22 from inverter / controller 24b, (e) the DC power supply bus 22 from DC voltage converter / controller 20b, and (f) the DC voltage converter / controller 20b from HP battery 18b.

[0047] Figure 7 is a flowchart showing the power flow while the system depicted in Figure 3 is operating in fault-tolerant mode. If one battery fails, the associated converter / controller is deactivated, isolating the failed battery from the DC power supply bus 22. The healthy battery then provides power to the load at a reduced power scale. In this case, load limiting may be necessary for some non-essential loads. In the embodiment depicted in Figure 7, the DC voltage converter / controller 20a is deactivated and the HE battery 18a is isolated (indicated by the dashed box) in response to the detection of a fault in the HE battery 18a by the SOC / SOH manager 16a.

[0048] Figure 8 is a flowchart showing the power flow while the system depicted in Figure 3 is operating in ground charging mode. In ground charging mode, all propulsion loads are deactivated. Some non-propulsion loads may also be deactivated. In this case, the charging station 8 supplies power (indicated by arrows pointing from the charging station 8 to the DC power bus 22) to charge the HE and HP batteries 18a and 18b under the control of the system controller 12.

[0049] The flowcharts and block diagrams in the various embodiments shown illustrate the structure, function, and operation of several possible embodiments of the apparatus and method in an exemplary embodiment. In this case, each block in the flowchart or block diagram may represent a module, segment, function, and / or part of a process or step. For example, one or more of the blocks are executable in hardware as program code, or as a combination of program code and hardware. When implemented in hardware, the hardware may take the form of an integrated circuit manufactured or configured to perform, for example, one or more operations in the flowchart or block diagram.

[0050] The embodiments disclosed above utilize one or more controllers. Such devices typically include processors or computers, such as central processing units, microprocessors, reduced instruction set computer processors, application-specific integrated circuits, programmable logic circuits, field-programmable gate arrays, digital signal processors, and / or any other circuits or processing devices capable of performing the functions described herein.

[0051] The methods described herein may be encoded as executable instructions embodied in a non-transient, tangible, computer-readable storage medium, including storage devices and / or memory devices. When such instructions are executed in a processing system or computer system, they cause system devices to perform at least a portion of the methods described herein.

[0052] Systems and methods for allocating load power drawn from HE and HP batteries to power the propulsion of a transport vehicle have been described with reference to various embodiments, but those skilled in the art will understand that various modifications are possible and elements can be substituted with equivalents, without departing from the scope of the teachings herein. In addition, numerous modifications can be made to adapt the teachings herein to specific circumstances without departing from the scope. Accordingly, the claims are not intended to be limited to the specific embodiments disclosed herein.

[0053] When used in the claims, “DC-AC converter” should be interpreted to include an inverter controlled by an inverter controller, and its structural equivalents.

[0054] Note: The following paragraphs describe further aspects of this disclosure. A1. A system for allocating load power drawn from a battery system to power the propulsion of a transport vehicle, DC power supply bus, A first DC voltage conversion system connected to the DC power supply bus, A high-energy battery connected to the first DC voltage conversion system, which is designed for optimal generation of DC power being propelled at high specific energy. A high-energy battery health management system configured to monitor the charge state and health state of the high-energy battery and generate a first battery status signal representing the charge state and health state of the high-energy battery, A second DC voltage conversion system connected to the DC power supply bus, A high-power battery connected to the second DC voltage conversion system, which is designed for optimal generation of DC power being propelled at high relative power, A high-power battery health management system configured to monitor the charge state and health state of the high-power battery and generate a second battery status signal representing the charge state and health state of the high-power battery, and A system controller that receives the first battery status signal and the second battery status signal and sends commands to the first DC voltage conversion system and the second DC voltage conversion system, wherein the first DC voltage conversion system and the second DC voltage conversion system allocate load power drawn from the high-energy battery and the high-power battery according to the propulsion phase of the transport body and the status of the high-energy battery and the high-power battery represented by the first battery status signal and the second battery status signal. A2. A first DC-AC converter connected to the DC power supply bus, A first propulsion load connected to receive AC power from the first DC-AC converter, A second DC-AC converter connected to the DC power supply bus, and The system further comprises a second propulsion load connected to receive AC power from the second DC-AC converter, The system according to paragraph A1, wherein the system controller is further configured to send commands to the first DC-AC converter and the second DC-AC converter to control the amount and frequency of the AC power supplied to the first propulsion load and the second propulsion load, respectively.

Claims

1. A system for allocating load power drawn from a battery system to supply power for the propulsion of an aircraft, High-energy batteries designed for optimal generation of DC power, which is being driven by high specific energy. A high-energy battery health management system configured to monitor the charge state and health state of the high-energy battery and generate a first battery status signal representing the charge state and health state of the high-energy battery, A high-power battery designed for optimal generation of DC power, which is being driven by high specific power output. A high-power battery health management system configured to monitor the charge state and health state of the high-power battery and generate a second battery status signal representing the charge state and health state of the high-power battery, A propulsion load configured to generate thrust using power converted from power generated by at least one of the high-energy battery and the high-power battery, and A system comprising a system controller configured to receive the first battery status signal and the second battery status signal, and then, depending on the propulsion phase of the aircraft's flight and the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal, to allocate load power drawn from the high-energy battery and the high-power battery for use with the propulsion load.

2. The system according to claim 1, wherein the system controller is configured to allocate load power drawn from the high-energy battery and the high-power battery, respectively, during the takeoff phase of the aircraft.

3. The system according to claim 1, wherein the system controller is configured to allocate the respective load power drawn from the high-energy battery and the high-power battery during the aircraft's ascent phase.

4. The system according to claim 1, wherein the system controller is configured to allocate a first load power drawn from the high-energy battery during the cruising phase of the aircraft without allocating any load power to the high-power battery, and further configured to allocate a second load power drawn from the high-energy battery to charging the high-power battery while the first load power is being drawn.

5. The system according to claim 1, wherein the system controller is further configured to cause at least one of the high-energy battery and the high-power battery to be partially recharged during the aircraft's descent phase using free energy supplied by gravity and aerodynamic drag.

6. A system for allocating load power drawn from a battery system to power the propulsion of a transport vehicle, High-energy batteries designed for optimal generation of DC power, which is being driven by high specific energy. A high-energy battery health management system configured to monitor the charge state and health state of the high-energy battery and generate a first battery status signal representing the charge state and health state of the high-energy battery, A high-power battery designed for optimal generation of DC power, which is being driven by high specific power output. A high-power battery health management system configured to monitor the charge state and health state of the high-power battery and generate a second battery status signal representing the charge state and health state of the high-power battery, A propulsion load configured to generate thrust using power converted from power generated by at least one of the high-energy battery and the high-power battery, and The system controller is configured to receive the first battery status signal and the second battery status signal, and then, according to the propulsion phase of the transporter and the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal, to allocate the load power drawn from the high-energy battery and the high-power battery for use by the propulsion load, The system controller is further configured to deactivate and isolate the high-energy battery in response to the first battery status signal indicating a fault condition in the high-energy battery, and to allocate load power at a reduced power scale drawn from the high-power battery.

7. A system for allocating load power drawn from a battery system to power the propulsion of a transport vehicle, High-energy batteries designed for optimal generation of DC power, which is being driven by high specific energy. A high-energy battery health management system configured to monitor the charge state and health state of the high-energy battery and generate a first battery status signal representing the charge state and health state of the high-energy battery, A high-power battery designed for optimal generation of DC power, which is being driven by high specific power output. A high-power battery health management system configured to monitor the charge state and health state of the high-power battery and generate a second battery status signal representing the charge state and health state of the high-power battery, A propulsion load configured to generate thrust using power converted from power generated by at least one of the high-energy battery and the high-power battery, and The system controller is configured to receive the first battery status signal and the second battery status signal, and then, according to the propulsion phase of the transporter and the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal, to allocate the load power drawn from the high-energy battery and the high-power battery for use by the propulsion load, The system controller is further configured to deactivate and isolate the high-power battery in response to the second battery status signal indicating a fault condition in the high-power battery, and to allocate load power at a reduced power scale drawn from the high-energy battery.

8. A computer-implemented method for allocating load power drawn from a battery system to power the propulsion of an aircraft, wherein the battery system comprises a high-energy battery designed for optimal generation of DC power during propulsion at high specific energy, and a high-power battery designed for optimal generation of DC power during propulsion at high specific power, and the method is (a) Monitoring the charge state and health status of the high-energy battery, (b) To generate a first battery status signal representing the charge state and health state of the high-energy battery, (c) Monitoring the charge state and health status of the high-power battery, (d) generating a second battery status signal representing the charge state and health state of the high-power battery, (e) A computer-implemented method comprising allocating load power drawn from the high-energy battery and the high-power battery in accordance with the flight phase of the aircraft and the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal.

9. The computer-implemented method according to claim 8, comprising step (e) allocating load power drawn from the high-energy battery and the high-power battery, respectively, during the takeoff phase of the aircraft.

10. The computer-implemented method according to claim 8, step (e) comprising allocating load power drawn from the high-energy battery and the high-power battery, respectively, during the ascent phase of the aircraft.

11. Step (e) comprises allocating a first load power drawn from the high-energy battery during the cruising phase of the aircraft, without allocating any load power to the high-power battery, and further comprising allocating a second load power drawn from the high-energy battery to charge the high-power battery while the first load power is being drawn. The computer-implemented method according to claim 8.

12. The computer-implemented method according to claim 8, further comprising partially recharging at least one of the high-energy battery and the high-power battery during the descent phase of the aircraft using free energy supplied by gravity and aerodynamic drag.

13. A computer-implemented method for allocating load power drawn from a battery system to power the propulsion of a transporter, wherein the battery system comprises a high-energy battery designed for optimal generation of DC power during propulsion at high specific energy, and a high-power battery designed for optimal generation of DC power during propulsion at high specific power, and the method is (a) Monitoring the charge state and health status of the high-energy battery, (b) To generate a first battery status signal representing the charge state and health state of the high-energy battery, (c) Monitoring the charge state and health status of the high-power battery, (d) generating a second battery status signal representing the charge state and health state of the high-power battery, (e) In the propulsion phase of the transporter, and in accordance with the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal, the load power drawn from the high-energy battery and the high-power battery is allocated. A computer-implemented method further comprising deactivating and disconnecting the high-energy battery and allocating load power at a reduced power scale drawn from the high-power battery in response to the first battery status signal indicating a fault condition in the high-energy battery.

14. A computer-implemented method for allocating load power drawn from a battery system to power the propulsion of a transporter, wherein the battery system comprises a high-energy battery designed for optimal generation of DC power during propulsion at high specific energy, and a high-power battery designed for optimal generation of DC power during propulsion at high specific power, and the method is (a) Monitoring the charge state and health status of the high-energy battery, (b) To generate a first battery status signal representing the charge state and health state of the high-energy battery, (c) Monitoring the charge state and health status of the high-power battery, (d) generating a second battery status signal representing the charge state and health state of the high-power battery, (e) In the propulsion phase of the transporter, and in accordance with the status of the high-energy battery and the high-power battery as represented by the first battery status signal and the second battery status signal, the load power drawn from the high-energy battery and the high-power battery is allocated. A computer-implemented method further comprising deactivating and disconnecting the high-power battery and allocating load power at a reduced power scale drawn from the high-energy battery in response to the second battery status signal indicating a fault condition in the high-power battery.

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