Power system, power pack assembly, and method for charging a load

Abstract

The present disclosure relates to power systems, power pack assemblies, and methods for charging a load. A power system includes a battery charging path and a capacitor charging path arranged in parallel. During a surge event, a current limiting element limits current flow along the battery charging path to release battery stress. During the surge event, current flow is also prevented between the battery and the load along a bypass path by a switching element. Under steady state charging conditions, the resistance of the current limiting element is reduced, thereby increasing current flow between the battery and the load along the battery charging path. Under steady state conditions, a switching circuit controls operation of the switching element, thereby also allowing current flow between the battery and the load along the bypass path. The change in resistance of the current limiting element and / or actuation of the switching element by the switching circuit is optionally based on a temperature change and is passively implemented without requiring an external control input signal.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and filing date benefit to U.S. Provisional Patent Application No. 63 / 016,087, filed April 27, 2020, the entire disclosure of which is incorporated herein by reference in its entirety. Background Technology

[0003] Fast charging and discharging events adversely affect battery performance, especially when they occur during use under high-power loads. Such inrush events can occur, for example, due to sudden demands from the load (e.g., during the initial establishment of electrical contact between the battery and the load) or due to a sudden flow of current to the battery during recharging.

[0004] Battery stress can be a particular concern for electric vehicles (EVs) given the high power demands of the main battery during a given period of operation and the frequent exposure to surge events (e.g., EV acceleration, regenerative braking, etc.). Reduced battery performance and capacity can lead to reduced vehicle performance, ultimately resulting in earlier and potentially more expensive battery replacements. Summary of the Invention

[0005] According to one implementation of this disclosure, a power system for a vehicle is provided, comprising a battery charge path and a capacitor charge path configured in parallel. The battery charge path is configured to supply current from the battery to a load. The capacitor charge path is configured to supply current from the capacitor to a load. A current limiting element having a variable resistance is connected in series along the battery charge path. The charge system also includes a bypass system. The bypass system includes a bypass path configured in parallel with the battery charge path. A switching element is provided along the bypass path. The switching element is configured to selectively prevent current from flowing along the bypass path and to allow current to flow along the bypass path. The switching circuit is configured to prevent current from flowing along the bypass path, while the current limiting element is defined by a resistor that substantially limits the flow of current between the battery and the load.

[0006] In some embodiments, when the current limiting element is defined by a resistor that substantially limits the flow of current between the battery and the load, the current flowing between the battery and the load is less than the current flowing along the capacitor charging path. The switching circuit can be optionally configured to allow current to flow along a bypass path, while the current limiting element is defined by a low resistance that allows current to flow between the battery and the load. In some embodiments, when the switching circuit operates to allow current to flow along the bypass path, substantially no current flows between the capacitor and the load along the capacitor charging path.

[0007] In various embodiments, the switching circuit includes a temperature-variable component having a resistance that changes in response to a first temperature change. The change in resistance may optionally be achieved without applying an external control input signal to the temperature-variable component. In some embodiments, the current-limiting element includes a thermistor having a resistance that changes in response to a second temperature change. The first temperature change may be the same as the second temperature change. Alternatively, the first temperature change may be different from the second temperature change.

[0008] The temperature-variable component optionally includes a positive temperature coefficient thermistor, and the thermistor element optionally includes a negative temperature coefficient thermistor. The resistance of the temperature-variable component increases in response to the core of the temperature-variable component reaching a predetermined temperature. The resistance of the thermistor element decreases in response to the core of the thermistor element reaching a predetermined temperature.

[0009] According to various embodiments, the switching element includes a semiconductor switch. The variation of the resistance of the temperature-variable component can be optionally configured to change the voltage signal applied to the gate of the semiconductor switch. The current-limiting element may optionally include a thermistor. The resistance of the thermistor may decrease in response to the core of the thermistor reaching a temperature exceeding a first threshold temperature range.

[0010] In response to the core of the temperature-variable component reaching a temperature exceeding a second threshold temperature range, a voltage signal applied to the gate of the semiconductor switch may optionally operate to allow current to flow through a bypass path. The second threshold temperature range corresponds to temperatures greater than a first threshold temperature range. The resistance of the temperature-variable component may optionally increase in response to the temperature of the core of the temperature-variable component exceeding the second threshold temperature range.

[0011] In some implementations, the switching circuit also includes a power supply and a resistor connected in series with the temperature-variable component. The temperature-variable component may optionally be directly physically coupled to the battery charging path.

[0012] According to another implementation of this disclosure, a power pack assembly is provided, comprising a housing and a power system supported by the housing. The housing includes a first portion configured to store a battery and a second portion configured to store a capacitor. The power system includes a battery charging path, a capacitor charging path, a current limiting element, and a bypass system. The battery charging path extends between the first portion of the housing and terminals supported by the housing. The capacitor charging path is arranged in parallel with the battery charging path and extends between the second portion of the housing and the terminals.

[0013] The current limiting element has a variable resistor and is connected in series along the battery charging path. The bypass system includes a bypass path, a switching element, and a switching circuit. The bypass path is connected in parallel with the battery charging path. The switching element is located along the bypass path. The switching element is configured to selectively limit current flow along the bypass path and allow current flow along the bypass path. The switching circuit is configured to operate the switching element to limit current flow along the bypass path.

[0014] The power assembly may also optionally include a battery and a capacitor. The battery is contained within a first portion of the housing and connected to terminals via a battery charging path. The capacitor is contained within a second portion of the housing and connected to terminals via a capacitor charging path. The switching circuit may optionally include a temperature-variable component with variable resistance. The switching circuit is configured to operate a switching element in response to temperature changes at the core of the temperature-variable component, selectively restricting current flow along a bypass path and allowing current flow along a bypass path.

[0015] According to another implementation of this disclosure, a method for charging a load is provided, the method comprising the steps of: allowing current from a battery to flow through a current-limiting element positioned along a battery charging path connecting the battery to the load; allowing current to flow from a capacitor to the load. The capacitor is positioned in parallel with the current-limiting element. A switching circuit is operated such that a switching element allows current to flow along a bypass path between the battery and the load, the bypass path being positioned in parallel with the battery charging path. The switching circuit operates the switching element to allow current to flow along the bypass path between the battery and the load, while simultaneously allowing the current from the battery to flow along the battery charging path to the battery.

[0016] The current limiting element optionally includes a thermistor, and the switching circuit optionally includes a temperature-variable component. The switching circuit operates the switching element based on a change in the resistance of the temperature-variable component. The change in resistance of the temperature-variable component occurs in response to the core temperature of the temperature-variable component reaching a first temperature. The thermistor allows current to flow along the battery charging path based on a decrease in the resistance of the thermistor. The change in resistance of the thermistor occurs in response to the core temperature of the thermistor reaching a second temperature. The core of the temperature-variable component reaches the first temperature after the current flowing from the capacitor to the load has stopped. The core of the thermistor reaches the second temperature before the current flowing from the capacitor to the load has stopped.

[0017] The present invention is merely illustrative and not intended to be limiting in any way. Other aspects, inventive features, and advantages of the apparatus or process described herein will become apparent from the detailed description set forth herein, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like elements. Attached Figure Description

[0018] The various objects, aspects, features, and advantages of this disclosure will become more apparent and better understood by referring to the detailed description taken in conjunction with the accompanying drawings, wherein the same reference numerals identify corresponding elements throughout. In the drawings, the same reference numerals generally indicate the same, functionally similar, and / or structurally similar elements.

[0019] Figure 1 This is a diagram of a power system according to one implementation method.

[0020] Figure 2 This is an example graph illustrating the resistance value of a thermistor relative to temperature according to one embodiment.

[0021] Figure 3 This is an example graph comparing the current flow from components of a charging system and a charging system according to one embodiment.

[0022] Figure 4 It is a circuit diagram of a power system according to one implementation method.

[0023] Figure 5 This is a circuit diagram of a high-power vehicle system utilizing an electric power system according to one embodiment.

[0024] Figure 6 An example of a power group system integrated into a power system according to one embodiment is shown. Detailed Implementation

[0025] Referring generally to the accompanying drawings, a power system 10 including a charging system 100 and a bypass system 400 is shown and described according to various embodiments. Typically, the charging system 100 mitigates battery stress during surge events (e.g., when establishing the initial electrical connection between the battery and the load). During steady-state operation, the bypass system 400 increases the efficiency of the power system 10 by providing an unrestricted current flow path through which current can be supplied between the battery and the load.

[0026] like Figure 1 As shown in the embodiment, the charging system 100 includes a battery 102 and a capacitor 106 connected in parallel. A battery charging path 103 connects the battery to a load 108, and a capacitor charging path 105 connects the capacitor 106 to both the load 108 and the battery 102.

[0027] The internal resistance of capacitors is typically relatively low, which allows them to respond quickly to surge events. Therefore, the series arrangement of capacitor 106 and battery 102 in charging system 100 allows capacitor 106 to provide current during surge events (e.g., when initial electrical contact is established between charging system 100 and load 108), thereby allowing battery 102 to gradually increase current as load 108 reaches a steady-state charge level. Once the steady-state charge level is reached, battery 102 takes over as the primary current source for load 108.

[0028] The rate at which current supplied individually by battery 102 and capacitor 106 flows to load 108 depends on the difference between the effective resistance of battery charging path 103 and the effective resistance of capacitor 106. In a circuit consisting only of a capacitor and a battery, the effective resistance of the battery charging path corresponds to the internal resistance of the battery, and the effective resistance of the capacitor corresponds to the internal resistance of the capacitor. Therefore, if the difference between the internal resistance of the battery and the internal resistance of the capacitor is small, the battery can still supply a significant portion (e.g., about half) of the current to the load during a surge event. Depending on the power requirements of the load, this reduction in current flow from the battery during a surge event may be insufficient to protect the battery from damage.

[0029] In contrast to batteries, capacitors exhibit minimal wear and degradation when subjected to surge currents. Therefore, as Figure 1 As shown, the charging system 100 further includes a current limiting element 104, which increases the effective resistance of the battery charging path 103 relative to the effective resistance of the capacitor 106. See below for reference. Figure 3During a surge event, the current limiting element 104 increases the rate and amount at which the capacitor 106 meets the current demand of the load 108, thereby limiting the rate and amount of current drawn from the battery 102. By extending the time during which the capacitor 106 serves as the primary current source for the load 108 during a surge event, the current limiting element 104 advantageously allows the battery 102 to gradually increase its current supply to the load 108 without jeopardizing its operating condition. Once a steady-state charge level is reached, the battery 102 is able to safely take over as the primary current source for the load 108.

[0030] The current limiting element 104 can be defined by a variety of different resistive elements. For example, according to some embodiments, the current limiting element 104 includes a resistor with a fixed resistance value (e.g., thick film, thin film, wire-wound arrangement, carbon composite, etc.). Since the resistor does not require any additional components or external control input signals for its operation, the resistor allows the current limiting device 104 to be easily and economically incorporated into the charging system 100.

[0031] While the resistance provided by the current limiting element 104, including a resistor, is advantageous during surge events, sustained restriction of current flow between the battery 102 and the load 108 is generally undesirable during steady-state charging conditions. Therefore, in other embodiments, the current limiting element 104 alternatively includes an active element having a variable resistance in response to an external control input signal (received via, for example, a controller, manual adjustment, etc.). Examples of such active elements include variable resistors, potentiometers, digital resistors, field-effect transistors operating in linear mode, etc.

[0032] By allowing the effective resistance of the battery charging path 103 to decrease after a surge event, the current limiting element 104, including the active element, advantageously increases the efficiency and speed at which the battery 102 can supply current to the load 108 under steady-state charging conditions. However, the increased number of components, complexity, and cost associated with the external input source required to operate the active element may limit the applicability of using the active element as the current limiting element 104 in various situations.

[0033] According to various embodiments, the current limiting element 104 advantageously includes a thermistor (e.g., a negative temperature coefficient thermistor) that changes in a predictable manner in response to temperature changes. Figure 2The graph representatively depicts the current-limiting element 104 of the thermistor having a large resistance at the initial low temperature. As the core temperature of the thermistor increases to the threshold temperature range, the resistance of the thermistor decreases non-linearly (e.g., exponentially). Once the core temperature has exceeded the threshold temperature range, the thermistor operates in a steady-state flow condition, where the thermistor provides minimal (e.g., none) resistance to the current flowing from the battery 102 to the load 108.

[0034] An increase in the core temperature of the current limiting element 104, including the thermistor, can occur due to heat dissipated through the thermistor during current flow. An increase in the core temperature of the thermistor can also occur due to changes in ambient temperature. For example, the core temperature of the thermistor can increase due to heat generated during operation by the load 108 or other components of the charging system 100. According to some embodiments, the thermistor may optionally be connected to the load 108 via a heat sink to increase the responsiveness of the thermistor to changes in ambient temperature.

[0035] The initial resistance of the thermistor and the threshold temperature range at which the thermistor reaches a steady-state flow state vary based on the thermistor's construction. Therefore, by selecting a thermistor suitable for the operating parameters and conditions of the load 108 used with the charging system 100, the current limiting element 104 of the thermistor can provide the benefits of both fixed resistors and active elements, while avoiding the limitations of each of these options.

[0036] That is, similar to the current limiting element 104 including an active element, the current limiting element 104 including a thermistor is capable of providing different levels of resistance to current flow, thereby allowing the effective resistance of the battery charging path 103 to decrease after a surge event. However, unlike the active element, the thermistor does not need to receive an external control input signal, but passively changes its resistance in response to temperature changes. Similar to the current limiting element 104 including a resistor, the absence of any need for additional components or external control components thus allows the current limiting element 104 including a thermistor to be easily and economically incorporated into the charging system 100.

[0037] Figure 3The diagram illustrates the current flow from the battery and capacitor in the charging system 100 (excluding the current limiting element 104) and the charging system 100 (including the current limiting element 104 with a thermistor) during a surge event. Curve 310 illustrates the time response of the current flow from the battery in the charging system. Curve 320 illustrates the time response of the current flow to and from the capacitor in the charging system. Curve 330 illustrates the time response of the current flow from the battery 102 in the charging system 100. Curve 340 illustrates the time response of the current flow to and from the capacitor 106 in the charging system 100.

[0038] like Figure 3 As illustrated in the graphs, in both the positive charging system (which does not include the current limiting element 104) and the charging system 100 (which includes the current limiting element 104 with a thermistor), the capacitor is the primary current source at the onset of a surge event. As the capacitor gradually depletes and the battery increases its current discharge, equilibrium points 301 and 302 are reached. Equilibrium points 301 and 302 correspond to the time when the current supplied by the capacitor equals the current supplied by the battery. After equilibrium points 301 and 302 are reached, the current supplied by the battery begins to exceed the current supplied by the capacitor. The capacitor continues to supply current to the load until it reaches transition points 303 and 304. After transition points 303 and 304 are reached, the capacitor stops supplying current to the load and begins to receive current from the battery (as evidenced by the positive current value of the capacitor's current flow). The battery continues to supply current to both the battery and the capacitor until recharging points 305 and 306 are reached, which correspond to the time when the capacitor has been recharged by the battery. After recharging points 305 and 306, the steady-state flow to the load is achieved by the current from battery discharge.

[0039] like Figure 3 As shown in the graph, the positive charging system (excluding the current limiting element 104) and the charging system 100 (including the current limiting element 104 with a thermistor) each achieve their respective transition points 303, 304 and recharge points 305, 306 at similar times. Therefore, incorporating the current limiting element 104 into the charging system 100 does not adversely affect the time required for the battery 102 to recharge the capacitor 106 after a surge event.

[0040] However, as shown by the comparison of the first curve 310 and the third curve 330, in the absence of a current-limiting element 104 for increasing the effective resistance of the flow between battery 102 and load 108, the rate of current from the battery in the positive charging system excluding the current-limiting element 104 is significantly greater than the rate of current from battery 102 in the charging system 100. Therefore, as shown by the comparison of the second curve 320 and the fourth curve 340, the amount of current supplied by the capacitor in the positive charging system is much lower than the amount of current supplied by the capacitor 106 in the charging system 100. Due to these variations in the rate of current supply between the capacitors and battery components in the positive charging system and the charging system 100, the positive charging system reaches its equilibrium point 301 much faster than the charging system 100 reaches its equilibrium point 302.

[0041] Therefore, as Figure 3 As illustrated in the call-out illustrations, when comparing the amount of energy supplied individually by the capacitors and batteries of the positive charging system and charging system 100 (the amount of energy is represented by the area under the respective curves between the start of the surge event and the occurrence of transition points 303, 304), the amount of energy supplied by the capacitors of the positive charging system (see illustration A) is substantially less than the amount of energy supplied by the batteries of the positive charging system (see illustration B). Conversely, the amount of energy supplied by the capacitor 106 of charging system 100 (see illustration C) is substantially greater than the amount of energy supplied by the battery 102 of charging system 100 (see illustration D). Therefore, as illustrated by the comparison of illustration B of the first curve 310 and illustration D of the third curve 330, the energy demand of the battery 102 of charging system 100 (which includes the current limiting element 104) is significantly less than the energy demand of the battery of the positive charging system excluding the current limiting element 104.

[0042] As described above, in embodiments where the current limiting element 104 includes a fixed resistor, the current is limited both during a surge event and during subsequent steady-state charging. While embodiments of the charging system 100 including the current limiting element 104 (including an active element or a thermistor) advantageously allow the effective resistance of the battery charging path 103 to decrease after a surge event, such embodiments of the current limiting element 104 can still provide some residual resistance to current flow during steady-state charging. As a result, the current limiting element 104 may cause heat dissipation as current flows from the battery 102 to the load 108, thereby reducing the efficiency of the charging system 100.

[0043] Therefore, as Figure 1 Typically exemplified, according to various embodiments, the power system 10 also includes a bypass system 400 that allows current to flow unrestricted from the battery 102 to the load 108 after a surge event. For example... Figure 1 As shown, the bypass system 400 includes a bypass path 401 having a switching element 403 arranged in parallel with the battery charging path 103. The switching element 403 can be selectively controlled to allow unrestricted current to flow from the battery 102 to the load 108 during steady-state charging conditions. Simultaneously, during surge events, the switching element 403 restricts current flow through the bypass path 401 to allow the charging system 100 to minimize stress on the battery 102 in the manner described above.

[0044] The switching circuit 420 of the bypass system 400 is operatively connected to the switching element 403 to enable the switching element 403 to switch between a flowing state (where current is diverted from the battery 102 to the load 108 via the bypass path 401) and a non-flowing state (where current is limited (e.g., prevented) from flowing through the bypass path 401) based on the operating state of the charging system 100 (i.e., steady-state level, surge events, etc.).

[0045] The switching element 403 can be defined by a variety of different constructions, components, and features. For example, the switching element 403 can be controlled by voltage-based signals, current-based signals, etc. The switching element 403 can be normally open or normally closed. See reference... Figure 4 As described in the example bypass system 400, the switching element 403 may optionally include a semiconductor switch 405. According to other embodiments, the switching element 403 may optionally include a relay switch. In still other embodiments, the switching element 403 may be defined by a variety of other structures.

[0046] The switching circuit 420 can utilize many different components, structures, and arrangements to operatively control the switching element 403 to achieve a flowing or non-flowing state in the bypass path 401. For example, the switching circuit 420 may include a controller that sends control input signals to the switching element 403 based on one or more measured or sensed parameters (e.g., detected current level, voltage, temperature, state of capacitor 106, etc.).

[0047] During operation of the charging system 100 charging the load 108, heat is gradually generated as current flows through the charging system 100 and towards the load 108. As described above, according to various embodiments, the current limiting element 104 advantageously includes a thermistor that utilizes the increased heat generated during power supply to the load 108 to passively (i.e., without requiring an external control input signal) change the resistance of the battery charging path 103 in a desired manner during operation of the charging system 100.

[0048] In a similar manner, the switching circuit 420 may also optionally utilize the temperature-variable component 421 to control the operation of the switching element 403 by taking advantage of the temperature rise that occurs during the charging of the load 108. Thus, just as the current-limiting element 104, which includes a thermistor, eliminates the need for a complex and expensive arrangement (through which its resistance variation is achieved), the use of the temperature-variable component 421 also provides the switching circuit 420 with a simple and economical option through which the desired control of the switching element 403 can be achieved.

[0049] The method by which the resistance change of the temperature-variable component 421 enables the switching circuit 420 to switch the switching element 403 between a flowing state and a non-flowing state can be implemented using a variety of different components and arrangements. Typically, the operation of the switching circuit 420 is based on the temperature-variable component 421 achieving a resistance that falls within a predetermined effective resistance range. When a resistance falling within the effective resistance range is obtained, the selection and arrangement of other components of the switching circuit 420 are configured to allow the switching circuit 420 to achieve the desired switching of the switching element 403. In this way, the temperature-variable component 421 can operate the switching element 403 without requiring an external control input signal.

[0050] As described above, it is desirable to prevent current from flowing through bypass path 401 during surge events in order to minimize the rate and amount of energy supplied by battery 102 to load 108 during surge events. Therefore, in various embodiments, the temperature-variable component 421 is configured such that the threshold temperature range of resistance falling within the effective resistance range of the temperature-variable component 421 corresponds to a temperature range having a minimum temperature equal to or greater than the expected temperature of charging system 100, load 108, and / or ambient environment during steady-state charging conditions.

[0051] To increase the responsiveness of the temperature-variable component 421 to temperature changes caused by the operation of the charging system 100, the temperature-variable component 421 is optionally positioned very close to the battery 102, the current limiting element 104, and / or the load 108. Alternatively, the temperature-variable component 421 may be optionally connected to the charging system 100 and / or the load 108 via a heat sink or other heat transfer device. For example, the temperature-variable component 421 may be optionally physically connected to a portion of the battery charging path 103 extending between the current limiting element 104 and the load 108 to increase the ability of the temperature-variable component 421 to respond to temperature changes caused by heat dissipated by the current limiting element 104.

[0052] In various embodiments, the temperature-variable component 421 includes a positive temperature-variable element (e.g., a positor or a positive temperature coefficient resistor) defined by low resistance at low temperatures and high resistance once the temperature of its core exceeds a threshold temperature range. In embodiments where the current-limiting element 104 of the charging system 100 used with the bypass system 400 includes a thermistor, the positive temperature-variable element defining the temperature-variable component 421 is optionally configured such that the positive temperature-variable element acquires a resistance falling within an effective resistance range at a threshold temperature range greater than the threshold temperature range at which the thermistor defining the current-limiting element 104 undergoes its resistance transition. This configuration of the temperature-variable component 421, including the positive temperature-variable element, can prevent the operation of the switching element 403 to achieve flow through the bypass path 401 during surge events.

[0053] According to other embodiments, the temperature-variable component 421 alternatively includes a negative temperature-variable element. The negative temperature-variable element functions in a manner similar to the thermistor described with reference to the current-limiting element 104 of the charging system 100, because the resistance of the negative temperature-variable element decreases when a threshold temperature range is exceeded. In embodiments where the current-limiting element 104 of the charging system 100 includes a thermistor, the thermistor defining the current-limiting element 104 and the negative temperature-variable element defining the temperature-variable component 421 may be defined by the same or similar construction. Optionally, in some such embodiments, the negative temperature-variable element defining the temperature-variable component 421 is configured such that it acquires a resistance falling within an effective resistance range at a threshold temperature range higher than the threshold temperature range at which the resistance of the thermistor defining the current-limiting element 104 decreases, in order to prevent premature actuation of the switching element 403 to allow current to flow through the bypass path 401.

[0054] The selection and arrangement of additional components defining the switching circuit 420 depend on the characteristics of the switching element 403 used in the bypass system 400 (e.g., the construction of the switching element 403, the bias voltage of the switching element 403, etc.) and the type of temperature-variable component 421 (e.g., a negative temperature-variable element or a positive temperature-variable element). The current flowing through the switching circuit 420 is supplied from the battery 102 or from a power source including an auxiliary source 430 separate from the battery 102. This auxiliary source 430 can include a variety of different sources, such as a DC source (e.g., a DC-DC converter), a vehicle accessory battery, etc. Alternatively, current can be supplied to the switching circuit 420 from the battery 102.

[0055] Typically, the additional components of the switching circuit 420 are selected and configured such that when the temperature variable component 421 obtains a resistance falling within the effective temperature range, the current flowing through the temperature variable component 421 and / or the resistance of the temperature variable component 421 causes the switching circuit 420 to provide a signal to the switching element 403 to realize the switching of the switching element 403.

[0056] For example, in an embodiment of a bypass system 400 in which the switching element 403 is controlled by the switching circuit 420 via a voltage-based signal (for example, such as...) Figure 4 In an embodiment of the bypass system 400, the switching circuit 420 optionally includes a resistor 410 and / or other elements configured as a voltage divider. This voltage divider configuration changes the voltage supplied to the gate 407 of the semiconductor switch 405 in response to temperature changes in the core of the temperature-variable component 421 (and consequently, changes in the resistance of the temperature-variable component 421). Therefore, when the temperature-variable component 421 acquires a resistance falling within its effective resistance range, the voltage signal supplied by the switching circuit 420 to the gate 407 corresponds to a voltage sufficient to achieve a switching action of the semiconductor switch 405.

[0057] Reference Figure 4 This illustrates a bypass system 400 according to an example implementation. For example... Figure 4 As illustrated, the switching element 403 includes a solid-state semiconductor switch 405 that limits or allows current flow based on a voltage applied by the switching circuit 420 to the gate 407 of the semiconductor switch 405. Non-limiting examples of the semiconductor switch 405 include, for example, field-effect transistors (FETs), such as junction field-effect transistors (JFETs), metal-oxide-semiconductor field-effect transistors (MOSFETs), or other similar types of FETs that can operate as switches based on the applied voltage.

[0058] like Figure 4 The implementation methods illustrated herein, in Figure 4 The implementation of the switching circuit 420 shown in the bypass system 400 uses a voltage divider arrangement of a temperature-variable component 421, which includes a negative temperature-variable component connected in series with a fixed resistor 410 to change the voltage supplied to the semiconductor switch 405. Therefore, when the resistance of the temperature-variable component 421 reaches a level within its effective resistance range (e.g., in response to heat dissipation during steady-state charging as a larger current pulls through the current-limiting element 104), the voltage supplied by the switching circuit 420 to the switching element 403 will correspond to a voltage falling within a threshold voltage range (configured to enable switching of the switching element 403), thereby allowing current from the battery 102 to flow through the bypass path 401 to the load 108.

[0059] Given the high power requirements of electric vehicles (“EVs”), the power system 10 is advantageously integrated into the EV power distribution system according to various implementation methods. (Refer to...) Figure 5 According to one example embodiment, a high-voltage power circuit 500 is shown that uses the power system 10 described in any of the above embodiments to supply current to one or more high-voltage loads 512 (e.g., 48V loads) (for example, electromechanical reversal control (EARC) of an EV, an electric turbine (E-turbine), a belt starter-generator (BSG), etc.).

[0060] Contactor 504 and / or current sensor 506 may optionally be connected in series with the EV's main battery 502. Contactor 504 may include any electronic or electromechanical device that disconnects battery 502 from the rest of circuit 500. For example, contactor 504 may be a relay, contactor, or other switch that can be manually or automatically configured to allow or prevent the flow of current to / from battery 502. Contactor 504 may optionally be controlled by control circuitry (not shown) to provide thermal protection, overvoltage protection, undervoltage protection, or other protection to circuit 500. Contactor 504 may optionally be replaced (or supplemented) with a fuse or other protective device.

[0061] An optional current sensor 506 measures the current flow to / from the battery 502. The current sensor 506 can monitor charging and discharging rates, as well as other parameters that may affect the operation or condition of the battery 502. In some embodiments, the current sensor 506 can be connected to optional control circuitry used to operate the contactor 504 based on the measured current flow to and from the battery 502.

[0062] An optional DC-DC converter 514 gradually reduces the power supplied by battery 502 and / or supercapacitor 510. The reduced power can be used for low-demand components 516 of the EV (e.g., headlights, power windows, radio, or other components of the EV) and / or to recharge low-power batteries 518 (e.g., 12V batteries).

[0063] The power system 10, including the charging system 100 and the bypass system 400, described according to any embodiment herein, can be electrically connected to the battery 502 and the supercapacitor 510 of the high-voltage power circuit 500 according to any number of different arrangements, configurations, etc. The power system 10 can optionally be integrated into other components of the EV. For example, in some embodiments, the power system 10 is connected via, for example, via... Figure 6 The power system 600 shown is typically integrated into the high-voltage power circuit 500.

[0064] like Figure 6 As illustrated, according to some embodiments, a battery 502, a supercapacitor 510, and a power system 10 are integrated into a hybrid power pack system 600. Battery cells 601 forming the battery 502 are stored within a first portion of a housing 610 (e.g., a first side of the interior cavity of the housing 610), and capacitor assemblies 603 forming the supercapacitor 510 are stored within a second portion of the housing 610 (e.g., a second side of the interior cavity of the housing 610). Electrical components of the power system 10 are integrated into any type of structure or configuration and are supported relative to the power pack housing 610 such that a battery charging path 103 connects the battery cells 601 to a positive terminal 605 supported by the housing 610, and a capacitor charging path 105 connects the capacitor assemblies 603 to a positive terminal 605. One or more battery cells 601 supported within the housing 610 may optionally be used to power a switching circuit 420. Alternatively, the auxiliary power source 430 for supplying power to the bypass system 400 is also supported by the power unit housing 610.

[0065] In such embodiments, the hybrid power system 600 can be directly connected to a load (e.g., high-voltage load 512) without requiring any additional components to be connected or wired to it. In some such embodiments, the power system 600 may also optionally include additional components (e.g., contactors, fuses, etc.) that are also supported within the power housing 610.

[0066] As used herein, the terms “approximately” and “approximately” will be understood by those skilled in the art and will vary to some extent depending on the context in which they are used. If the use of these terms is unclear to those skilled in the art, then, given the context in which they are used, “approximately” and “approximately” will mean up to plus or minus 10% of the particular term.

[0067] Unless otherwise specified herein or obviously contradicted by the context, the terms “a” and “the”, and similar designations, are to be interpreted as encompassing both the singular and the plural in the context of describing elements (especially in the context of the appended claims). Unless otherwise specified herein, the enumeration of numerical ranges herein is intended only as a convenient method of individually referring to individual values ​​falling within that range, and each individual value is incorporated into this specification as if it were individually enumerated herein. Unless otherwise specified herein or obviously contradicted by the context, all methods described herein may be performed in any suitable order. Unless otherwise stated, the use of any and all examples or exemplary language (e.g., “such as”) provided herein is intended only to better illustrate the implementation and does not limit the scope of the claims. No language in the specification should be construed as indicating that any unclaimed element is necessary.

[0068] While certain embodiments have been illustrated and described, it should be understood that changes and modifications can be made therein by those skilled in the art without departing from the technology as defined in its broader aspects as in the appended claims.

[0069] The embodiments illustratively described herein can be practiced appropriately without the presence of any one or more elements or limitations not specifically disclosed herein. Therefore, terms such as “comprising,” “including,” and “containing” should be interpreted broadly and without limitation. Furthermore, the terminology and expressions used herein have been used as descriptive rather than limiting terms, and the use of such terminology and expressions is not intended to exclude any equivalents of the shown and described features or portions thereof, but rather to recognize that various modifications may fall within the scope of the claimed technology. Additionally, the phrase “consistently of…” should be understood to include those specifically listed elements, as well as those additional elements that do not substantially affect the basic and novel features of the claimed technology. The phrase “consisting of…” excludes any unspecified elements.

[0070] This disclosure is not limited to the specific embodiments described herein. Many modifications and variations can be made without departing from the spirit and scope of the invention, as will be apparent to those skilled in the art. Based on the foregoing description, functionally equivalent methods and apparatuses within the scope of this disclosure will be apparent to those skilled in the art, in addition to those methods and apparatuses listed herein. Such modifications and variations fall within the scope of the appended claims. This disclosure is limited only by the appended claims together with all equivalents granted by such claims. It should be understood that this disclosure is not limited to specific methods, reactants, compound compositions, or biological systems, which can certainly be changed. It should also be understood that the terminology used herein is for describing specific embodiments only and is not intended to be limiting.

[0071] Furthermore, where features or aspects of this disclosure are described in accordance with the Markush Group, those skilled in the art will recognize that this disclosure is therefore also described in accordance with any individual member or group of members of the Markush Group.

[0072] As those skilled in the art will understand, for any and all purposes, particularly for the purpose of providing a written description, all scopes disclosed herein also encompass any and all possible subscopes and combinations thereof. Any listed scope can be readily considered sufficiently descriptive and such that the same scope can be decomposed into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each scope discussed herein can be readily decomposed into a lower third, a middle third, and an upper third, etc. Those skilled in the art will also understand that all language such as “up to,” “at least,” “greater than,” “less than,” etc., includes the listed numbers and refers to a scope that can subsequently be decomposed into subscopes as discussed above. Finally, those skilled in the art will understand that a scope includes individual elements.

[0073] Other embodiments are set forth in the appended claims.

Claims

1. An electrical system for a vehicle, the electrical system comprising: A battery charging path and a capacitor charging path are connected in parallel with each other. The battery charging path is configured to provide current from the battery to the load, and the capacitor charging path is configured to provide current from the capacitor to the load. A first thermistor is connected in series along the battery charging path and has a resistance that decreases as the first temperature increases to a first threshold temperature range. Bypass system, the bypass system comprising: A bypass path, wherein the bypass path is configured in parallel with the battery charging path; A switching element disposed along the bypass path, the switching element including a gate configured to achieve a switching action to selectively prevent current from flowing along the bypass path and to allow current to flow along the bypass path; and The switching circuit includes: A second thermistor, the second thermistor having a resistance that increases in response to a second temperature increasing to a second threshold temperature range; A resistor arranged in a voltage divider configuration, wherein the voltage divider configuration is configured to change the voltage supplied to the gate of the switching element in response to a change in the resistance of the second thermistor based on an increase in the second temperature; In response to the second temperature being below the second threshold temperature range, the switching circuit is configured to prevent current from flowing along the bypass path while the first thermistor is limited by a resistor that substantially restricts current flow between the battery and the load. In response to the second temperature exceeding the second threshold temperature range, the switching circuit is configured to allow current to flow along the bypass path while the first thermistor is limited by a low resistance that allows current to flow between the battery and the load. The power system is configured such that, during operation, the first thermistor reaches the first threshold temperature range before the current flowing from the capacitor to the load has stopped, and the second thermistor reaches the second threshold temperature range after the current flowing from the capacitor to the load has stopped.

2. The power system according to claim 1, wherein, When the first thermistor is defined by a resistor that substantially restricts the flow of current between the battery and the load, the current flowing between the battery and the load is less than the current flowing along the charging path of the capacitor.

3. The power system according to claim 1, wherein, When the switching circuit operates to allow current to flow along the bypass path, substantially no current flows between the capacitor and the load along the capacitor charging path.

4. The power system according to claim 1, wherein, The increase in resistance of the second thermistor is achieved without applying an external control input signal.

5. The power system according to claim 1, wherein, The second temperature includes the core temperature of the second thermistor, and the first temperature includes the core temperature of the first thermistor.

6. The power system according to claim 1, wherein, The switching element includes a semiconductor switch.

7. The power system according to claim 1, wherein, The resistance of the first thermistor decreases exponentially in response to the first temperature reaching a temperature exceeding the first threshold temperature range.

8. The power system according to claim 1, wherein, The second threshold temperature range corresponds to a temperature greater than the first threshold temperature range.

9. The power system according to claim 1, wherein, The switching circuit also includes a power supply connected in series with the second thermistor.

10. The power system according to claim 1, wherein, The second thermistor is directly and physically connected to the battery charging path.

11. A power assembly, the power assembly comprising: A housing having a first portion configured to store a battery and a second portion configured to store a capacitor; as well as An electrical system supported by the housing, the electrical system comprising: A battery charging path extends between the first portion of the housing and a terminal supported by the housing; A capacitor charging path is provided in parallel with the battery charging path, and the capacitor charging path extends between the second part of the housing and the terminal. A first thermistor is connected in series along the battery charging path and has a resistance that decreases as the first temperature increases to a first threshold temperature range. Bypass system, the bypass system comprising: A bypass path, wherein the bypass path is configured in parallel with the battery charging path; A switching element disposed along the bypass path, the switching element including a gate configured to achieve switching of the switching element to selectively restrict current flow along the bypass path and to allow current flow along the bypass path; and A switching circuit configured to operate the switching element to limit current flow along the bypass path; the switching circuit includes: A second thermistor, the second thermistor having a resistance that increases in response to a second temperature increasing to a second threshold temperature range; and A resistor arranged in a voltage divider configuration, wherein the voltage divider configuration is configured to change the voltage supplied to the gate of the switching element in response to a change in the resistance of the second thermistor based on an increase in the second temperature; In response to the second temperature being below the second threshold temperature range, the switching circuit is configured to prevent current from flowing along the bypass path while the first thermistor is limited by a high resistance that substantially restricts current flow between the battery and the load. Wherein, in response to the second temperature exceeding the second threshold temperature range, the switching circuit is configured to allow current to flow along the bypass path while the first thermistor is limited by a low resistance that allows current to flow between the battery and the load, and The power system is configured such that, during operation, the first thermistor reaches the first threshold temperature range before the current flowing from the capacitor to the load has stopped, and the second thermistor reaches the second threshold temperature range after the current flowing from the capacitor to the load has stopped.

12. The power assembly according to claim 11, further comprising: The battery; as well as The capacitor; The battery is contained within the first portion of the housing and connected to the terminal via the battery charging path; and The capacitor is contained within the second part of the housing and is connected to the terminal via the capacitor charging path.

13. The power assembly according to claim 11, wherein, The increase in the second temperature includes a temperature change in the core of the second thermistor.

14. A method for charging a load, the method comprising the steps of: Current from the battery flows through a first thermistor positioned along the battery charging path, which connects the battery to the load. To allow current to flow from the capacitor to the load, wherein the capacitor is positioned in parallel with the first thermistor; and Operating the switching circuit to allow current to flow between the battery and the load along a bypass path, the bypass path being configured in parallel with the battery charging path, wherein operating the switching circuit includes changing the voltage supplied to the gate of the switching element in response to a change in the resistance of a second thermistor of the switching circuit via a resistor arranged in a voltage divider configuration. The resistance change of the second thermistor is in response to an increase in the temperature of the second thermistor; and In response to the temperature being below a threshold temperature range, the switching circuit is configured to prevent current from flowing along the bypass path while the first thermistor is limited by a high resistance that substantially restricts current flow between the battery and the load. In response to the temperature exceeding the threshold temperature range, the switching circuit operates the switching element to allow current to flow along the bypass path between the battery and the load, while simultaneously allowing the current from the battery to flow along the battery charging path to the battery. The first thermistor reaches a first threshold temperature range before the current flowing from the capacitor to the load has stopped, and the second thermistor reaches a second threshold temperature range after the current flowing from the capacitor to the load has stopped.

Images