Sample-and-hold techniques for reading charger current in discontinuous conduction mode

Abstract

The present disclosure relates to sample-and-hold techniques for reading charger current in discontinuous conduction mode. The current monitoring system may include a sample-and-hold circuit to generate a sample-and-hold signal (S / H signal), where the S / H signal corresponds to a peak value of a current in the charging circuit during a switching period of the charging circuit. The system may also include a first analog-to-digital channel (ADC channel) for sampling the S / H signal; and a second ADC channel configured to sample a current in the charging circuit. The system may then determine an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in the discontinuous conduction mode, and determine an average current of the charging circuit based on the second ADC channel when the charging circuit is operating in the continuous conduction mode.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 661,253, filed June 18, 2024, entitled “SAMPLE ANDHOLD TECHNIQUE FOR READING CHARGER CURRENT IN DISCONTINUOUS CONDUCTION MODE”, which designates Luigi Balma and Livio Allesandro Tilotta as inventors, and is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure generally relates to current monitoring in battery charging circuit systems, and more specifically to current monitoring in battery charging circuit systems when in discontinuous conduction mode. Background Technology

[0004] In many battery charging devices, such as, but not limited to, uninterruptible power supplies (UPS), the battery charging circuitry shares a converter with the boost circuitry. However, the current characteristics in charging and boost applications can vary significantly. In some cases, such devices may enter discontinuous conduction mode (DCM) while performing charging. However, monitoring and / or estimating the current used for battery charging in DCM can be difficult or impractical. In particular, the current may have a discontinuous characteristic in which the location of current peaks can be unpredictable. Therefore, there is a need to develop systems and methods for providing current monitoring in DCM. Summary of the Invention

[0005] In an embodiment, the technology described herein relates to a current monitoring system comprising: a sample-and-hold circuit configured to generate a sample-and-hold signal (S / H signal), wherein the S / H signal corresponds to the peak value of the current in the charging circuit during a switching cycle of the charging circuit; a first analog-to-digital converter (ADC) channel for sampling the S / H signal; a second ADC channel configured to sample the current in the charging circuit; and a controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: determine an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in a discontinuous conduction mode; and determine an average current of the charging circuit based on the second ADC channel when the charging circuit is operating in a continuous conduction mode.

[0006] In embodiments, the technology described herein relates to a current monitoring system, wherein the program instructions are further configured to cause the one or more processors to generate a control signal for controlling one or more switches in the charging circuit.

[0007] In embodiments, the technology described herein relates to a current monitoring system, wherein the charging circuit comprises a battery charging circuit.

[0008] In embodiments, the technology described herein relates to a current monitoring system, wherein the battery charging circuit is integrated within an uninterruptible power supply.

[0009] In embodiments, the technology described herein relates to a current monitoring system, wherein the sample-and-hold circuit comprises one or more capacitors configured to hold a charge corresponding to a peak of the current in the charging circuit within a switching period.

[0010] In embodiments, the technology described herein relates to a current monitoring system, wherein determining an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in a discontinuous conduction mode comprises determining the average current of the charging circuit based on the first ADC channel, and one or more additional characteristics of the current in the charging circuit.

[0011] In embodiments, the technology described herein relates to a current monitoring system, wherein the one or more additional characteristics of the current in the charging circuit comprise at least one of: a switching period of the charging circuit, a duty cycle of a conduction mode of the charging circuit relative to the switching period, or a peak of the current within the switching period according to the S / H signal.

[0012] In embodiments, the technology described herein relates to a current monitoring system, wherein the charging circuit comprises a battery charging circuit, wherein the one or more additional characteristics of the current in the charging circuit comprise at least one of: a switching period of the charging circuit, a duty cycle of a conduction mode of the charging circuit relative to the switching period, a peak of the current within the switching period according to the S / H signal, a voltage of a battery charged by the charging circuit, or an inductance of an inductor in the charging circuit.

[0013] In embodiments, the technology described herein relates to a current monitoring method comprising: generating a sample-and-hold signal (S / H signal) corresponding to a peak of a current in a charging circuit over a switching period of the charging circuit; sampling the S / H signal with a first analog-to-digital channel (ADC channel); sampling the current in the charging circuit with a second ADC channel; determining an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in a discontinuous conduction mode; and determining the average current of the charging circuit based on the second ADC channel when the charging circuit is operating in a continuous conduction mode.

[0014] In embodiments, the technology described herein relates to a current monitoring method further comprising generating a control signal for controlling one or more switches in the charging circuit.

[0015] In embodiments, the technology described herein relates to a current monitoring method, wherein the charging circuit comprises a battery charging circuit.

[0016] In embodiments, the technology described herein relates to a current monitoring method, wherein the battery charging circuit is integrated within an uninterruptible power supply device.

[0017] In embodiments, the technology described herein relates to a current monitoring method, wherein the sample-and-hold circuit comprises one or more capacitors configured to hold a charge corresponding to the peak of the current in the charging circuit over the switching period.

[0018] In embodiments, the technology described herein relates to a current monitoring method, wherein determining the average current of the charging circuit based on the first ADC channel when the charging circuit is operating in the discontinuous conduction mode comprises determining the average current of the charging circuit based on the first ADC channel and one or more additional characteristics of the current in the charging circuit.

[0019] In embodiments, the technology described herein relates to a current monitoring method, wherein the one or more additional characteristics of the current in the charging circuit comprise at least one of: a switching period of the charging circuit, a duty cycle of a conduction mode of the charging circuit relative to the switching period, or the peak of the current over the switching period according to the S / H signal.

[0020] In implementations, the technology described herein relates to a current monitoring method, where the charging circuit comprises a battery charging circuit, where the one or more additional characteristics of the current in the charging circuit comprise at least one of: a switching period of the charging circuit, a duty cycle of the on- mode of the charging circuit relative to the switching period, a peak value of the current within the switching period according to the S / H signal, a voltage of a battery charged by the charging circuit, or an inductance of an inductor in the charging circuit.

[0021] In implementations, the technology described herein relates to an uninterruptible power supply device, comprising: a battery charging circuit to charge a battery; a sample-and-hold circuit configured to generate a sample-and-hold signal (S / H signal), where the S / H signal corresponds to a peak value of a current in the charging circuit within a switching period of the charging circuit; a first analog-to-digital channel (ADC channel) to sample the S / H signal; a second ADC channel configured to sample the current in the charging circuit; and a controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: determine an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in a discontinuous on-mode; and determine an average current of the charging circuit based on the second ADC channel when the charging circuit is operating in a continuous on-mode.

[0022] In implementations, the technology described herein relates to an uninterruptible power supply device, where the program instructions are further configured to cause the one or more processors to generate a control signal to control one or more switches in the charging circuit.

[0023] In implementations, the technology described herein relates to an uninterruptible power supply device, where determining an average current of the charging circuit based on the first ADC channel when the charging circuit is operating in a discontinuous on-mode comprises determining the average current of the charging circuit based on the first ADC channel and one or more additional characteristics of the current in the charging circuit.

[0024] In implementations, the technology described herein relates to an uninterruptible power supply device, where the one or more additional characteristics of the current in the charging circuit comprise at least one of: a switching period of the charging circuit, a duty cycle of the on- mode of the charging circuit relative to the switching period, a peak value of the current within the switching period according to the S / H signal, a voltage of a battery charged by the charging circuit, or an inductance of an inductor in the charging circuit.

[0025] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not necessarily restrictive of the application as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and together with the general description, serve to explain the principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0026] Those skilled in the art can better appreciate many of the advantages of the present disclosure by reference to the drawings.

[0027] Figure 1 A block diagram view of a current monitoring system is shown in accordance with one or more embodiments of the present disclosure.

[0028] Figure 2 A simplified schematic of a charging circuit is shown in accordance with one or more embodiments of the present disclosure.

[0029] Figure 3 Challenges associated with determining average current of a charging circuit in DCM are shown in accordance with one or more embodiments of the present disclosure.

[0030] Figure 4 Current waveforms associated with DCM operation and S / H signals generated by S / H circuit are shown in accordance with one or more embodiments of the present disclosure.

[0031] Figure 5 Various parameters of current waveforms are shown in accordance with one or more embodiments of the present disclosure.

[0032] Figure 6 A plot of average current as a function for selected conditions is shown in accordance with one or more embodiments of the present disclosure.

[0033] Figure 7 Weights as a function of duty cycle are shown in accordance with one or more embodiments of the present disclosure.

[0034] Figure 8 A flowchart showing steps performed in a method for monitoring current in a charging circuit is shown in accordance with one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0035] Reference will now be made in detail to the disclosed subject matter. The present disclosure has been particularly shown and described with reference to certain embodiments and specific features thereof. The embodiments set forth herein are considered to be illustrative and not restrictive of the disclosure. It will be apparent to those of ordinary skill in the art that various changes and modifications can be made without departing from the spirit and scope of the disclosure.

[0036] Embodiments of the present disclosure relate to systems and methods that provide current monitoring for a charging circuit (e.g., a battery charging circuit) operating in discontinuous conduction mode (DCM). In many applications, current monitoring (e.g., monitoring of average current, etc.) is used in a control loop for driving one or more switches in the charging circuit. In DCM, the current within an inductor of the charging circuit reaches zero within a switching period, which can occur in the presence of a relatively light load (e.g., when near the end-of-charge voltage in a battery charging application). In this mode, typical techniques for monitoring average current can be impractical or ineffective. For example, sampling the current in DCM can fail to capture the current waveform and can oversample the zero current time.

[0037] In embodiments, the current monitoring system implements a sample-and-hold (S / H) technique in which a sample-and-hold signal (S / H signal) is generated that maintains the peak current of a particular current pulse between current pulses. Such a signal can be readily sampled to provide the peak current for each current pulse. Average current can then be determined based on additional information about the current waveform, such as but not limited to, duty cycle, period (or frequency) of the current pulses, inductance in the charging circuit, or peak current. Moreover, in a battery charging application, the battery voltage can also be used to determine average current.

[0038] For example, the current monitoring system can include a dedicated sample-and-hold circuit (S / H circuit) designed to generate the S / H signal and at least two ADC converter (analog-to-digital converter) channels or ADC converter channels. In this configuration, a first ADC channel can sample the current in the S / H circuit and a second ADC channel can directly sample the charging circuit. The first ADC channel can be used to determine average current for the charging circuit based on the S / H signal when the charging circuit is operating in DCM. The second ADC channel can be used to determine average current for the charging circuit using traditional techniques when the charging circuit is operating in continuous conduction mode (CCM).

[0039] Reference is now made to Figures 1 to 8 systems and methods for providing current monitoring for a charging circuit in DCM using a sample-and-hold technique are described in greater detail in accordance with one or more embodiments of the present disclosure.

[0040] Figure 1 A block diagram view of a current monitoring system 100 is shown in accordance with one or more embodiments of the present disclosure.

[0041] The current monitoring system 100 can be configured to monitor and optionally control current in a charging circuit 102 (e.g., but not limited to, a battery charging circuit). As an illustration, the charging circuit 102 can be integrated within an uninterruptible power supply (UPS).

[0042] In some implementations, the current monitoring system 100 includes a sample-and-hold circuit 104 (e.g., S / H circuit 104) to generate a sample-and-hold signal (S / H signal), where the S / H signal corresponds to a peak value of current through the charging circuit 102 over a switching period T.

[0043] In some implementations, the current monitoring system 100 includes one or more ADC channels 106 to capture data associated with current through the charging circuit 102 and a controller 108 to determine one or more measurements associated with current through the charging circuit 102 based on data from the one or more ADC channels 106. The one or more ADC channels 106 can capture any type of data indicative of or related to current through the charging circuit 102. For example, the one or more ADC channels 106 can capture data from one or more transducers or other sensors indicative of or related to current.

[0044] As an illustration, the current monitoring system 100 can include at least a first ADC channel 106-1 to capture the S / H signal, and can optionally include a second ADC channel 106-2 to directly capture current through the charging circuit 102.

[0045] The controller 108 can generate any number of measurements associated with current through the charging circuit 102 based on data captured by the one or more ADC channels 106. For example, the controller 108 can generate a measurement of an average value of current through the charging circuit 102 over a selected time frame (e.g., a rolling window). As another example, the controller 108 can generate a drive signal for one or more switches 202 in the charging circuit 102 to control operation of the charging circuit 102. In this way, the controller 108 can implement a charging control algorithm to charge a battery based at least in part on measurements associated with current through the charging circuit 102.

[0046] In some embodiments, the controller 108 includes one or more processors 110. For example, the one or more processors 110 can be configured to execute a set of program instructions maintained in a memory 112 or memory device. The one or more processors 110 of the controller 108 can include any processing element known in the art. In this sense, the one or more processors 110 can include any microprocessor-type device configured to execute algorithms and / or instructions. For example, the one or more processors 110 can include, but are not limited to, one or more central processing units (CPUs), one or more graphics processing units (GPUs), one or more microprocessors, one or more digital signal processors (DSPs), one or more field- programmable gate array (FPGA) devices, or one or more application-specific integrated circuits (ASICs).

[0047] Further, the memory 112 can include any storage media suitable for storing program instructions that can be executed by the associated one or more processors 110. For example, the memory 112 can include non-transitory storage media. As an additional example, the memory 112 can include, but is not limited to, read-only memory, random access memory, magnetic or optical storage devices (e.g., magnetic diskettes, magnetic tapes, solid state drives, etc.). It should also be noted that the memory 112 can be housed in a common controller housing with the one or more processors 110 or in different housings.

[0048] Figure 2 A simplified schematic of a charging circuit 102 is shown in accordance with one or more embodiments of the present disclosure.

[0049] In some embodiments, the charging circuit 102 includes one or more switches 202 that control operation of the charging circuit 102. The one or more switches 202 can be of any type known in the art, such as, but not limited to, one or more insulated gate bipolar transistors.

[0050] For example, Figure 2 A configuration is depicted in which the charging circuit 102 includes a switch 202 and an inductor 204 between a charging voltage source (V dc ) and a battery terminal (V bat ). In this configuration, the switch 202 controls whether the battery (e.g., V bat ) is connected to the charging voltage source (V dc ). Further, Figure 2 The configuration in FIG. 1 includes a diode 206 for controlling current flow. However, it should be appreciated that Figure 2are provided for illustrative purposes only and should not be construed as limiting the scope of the disclosure. Rather, the charging circuit 102 can have any number or type of components suitable for charging a battery.

[0051] One or more switches 202 in the charging circuit 102 can be driven by a drive signal that controls the state of the one or more switches. By way of illustration, one or more switches in the charging circuit 102 can be driven by a pulse width modulation (PWM) drive signal using PWM control techniques. In this configuration, the control signal can include a periodic signal having a switching period (e.g., a switching frequency) with a varying duty cycle. For example, the duty cycle can define the percentage of the switching period associated with an “on” mode in which an inductor (e.g., inductor 204) is charged. The drive signal can be generated using any component such as, but not limited to, the controller 108.

[0052] Data associated with the current through the charging circuit 102 can be used for various purposes such as, but not limited to, implementing a charging control algorithm suitable for driving one or more switches 202. For example, the charging control algorithm can utilize average current as feedback.

[0053] The charging circuit 102 can generally operate in either continuous conduction mode (CCM) or discontinuous conduction mode (DCM). In CCM, the current through the charging circuit 102 (e.g., the current through the inductor 204 in Figure 2 is always greater than zero. In DCM, the current through the charging circuit 102 can drop to zero during a switching period. The DCM mode can be triggered by any condition, but generally can occur when the charging circuit 102 approaches the end-of-charge voltage (e.g., when the battery being charged approaches capacity).

[0054] It is noted that various aspects of the current waveform in DCM (such as, but not limited to, the shape, peak current, or timing of the peak current) can be unpredictable. Thus, it is contemplated herein that monitoring the average current through the charging circuit 102 can be difficult and / or impractical to monitor when in DCM.

[0055] Figure 3 Challenges associated with determining the average current through the charging circuit 102 in DCM are illustrated. Specifically, Figure 3 A current waveform 302 is depicted featuring a greater-than-zero current region 304 and a zero-current region 306, where the start of the greater-than-zero current region 304 is separated by a switching period T. Figure 3Periodic sampling times 308 for sampling the current waveform 302 (e.g., with the second ADC channel 106-2) are also depicted. In this example, the sampling times 308 fall within the zero current region 306, which will result in a false average current measurement of zero. Moreover, even if the sampling times 308 correspond to the greater than zero current region 304, the measurement of average current cannot accurately reflect the true average current.

[0056] Accordingly, in some implementations, the current monitoring system 100 can utilize the S / H circuit 104 to generate a sample-and-hold signal (S / H signal) that corresponds to the peak value of the current through the charging circuit 102 over a switching period T.

[0057] By way of illustration, Figure 4 A current waveform 402 associated with DCM operation and a S / H signal 404 generated by the S / H circuit 104 are shown in accordance with one or more implementations of the present disclosure. In this example, the current waveform 402 includes greater than zero current regions 406 and zero current regions 408 and sampling times 410 that fall in the zero current regions 408 in a manner similar to Figure 4 The current waveform 402 includes greater than zero current regions 406 and zero current regions 408 and sampling times 410 that fall in the zero current regions 408 in a manner similar to Figure 3 However, the greater than zero current regions 406 of the current waveform 402 in Figure 4 The greater than zero current regions 406 of the current waveform 402 in

[0058] However, the S / H signal 404 maintains the peak voltage associated with each of the greater than zero current regions 406 until the subsequent greater than zero current region 406. For example, a first peak current 412 associated with a first greater than zero current region 406-1 is held above a first zero current region 408-1, a second peak current 414 associated with a second greater than zero current region 406-2 is held above a second zero current region 408-2, and so on. In this configuration, the value of the current waveform 402 sampled during the sampling times 410 can correspond to the peak value over the associated switching period T.

[0059] The S / H circuit 104 can include any number or type of components suitable to provide the S / H signal 404 that includes the peak current over each switching period T. For example, the S / H circuit 104 can include at least a capacitor for storing charge associated with the peak current. Moreover, the S / H circuit 104 can include additional components, such as but not limited to additional switches or operational amplifiers.

[0060] In some implementations, the S / H circuit 404 is associated with a drive signal (e.g., a PWM drive signal) for one or more switches 202 of the charging circuit 102. For example, when the drive signal is associated with an "on" mode, the S / H signal 404 can follow (or correspond to) the current through the charging circuit 102. Otherwise, the S / H signal 404 can hold the current value (e.g., the peak current) until the next "on" mode.

[0061] The S / H signal 404 can take any form so long as it maintains a peak of the current in the region 406 greater than zero. For example, the S / H signal 404 can precisely track any positive rise of the current waveform 402 in the region 406 greater than zero. As another example, as shown, the S / H signal 404 can slightly lag the current waveform 402 during positive rises of the current waveform 402 in the region 406 greater than zero and hold until a subsequent region 406 greater than zero during the zero current region 408. Further, the S / H signal 404 can provide a controlled transition from the zero current region 408 to the region 406 greater than zero. Figure 4

[0062] The measurement of average current through the charging circuit 102 (e.g., through the inductor 204 in the charging circuit 102) under CCM and DCM according to one or more implementations of the present disclosure will now be described in more detail. The measurement of average current through the charging circuit 102 can be generated using any suitable technique. Figure 2

[0063] In some implementations, when the charging circuit 102 is operating under CCM, the average current can be determined based on the measurement of current (if present) from the second ADC channel 106-2.

[0064] In some implementations, when the charging circuit 102 is operating under DCM, the average current can be determined based on the measurement of the S / H signal 404 from the first ADC channel 106-1. Further, the measurement of average current can be generated based on the measurement of the S / H signal 404 from the first ADC channel 106-1 using any suitable technique.

[0065] For example, the average current (I avg ) can be calculated as:

[0066]

[0067] t on = Duty - T (2)

[0068] ​​where T is the switching period of one or more switches 202 in the charging circuit 102 (e.g., as depicted in Figures 3 to 4 on is the time associated with the "on" mode of the charging circuit 102 (e.g., in which the inductor 204 in Figure 2 is charged), Duty is the duty cycle associated with t on relative to the switching period T, t off is the time associated with a current greater than zero after the end of the "on" phase, and i PK is the peak current (e.g., the peak current associated with the current pulse) within the switching period T.

[0069] Figure 5 Various parameters of the current waveform 502 are shown in accordance with one or more embodiments of the present disclosure. Specifically, Figure 5 the relationship between the switching period T, the peak current (i PK ), and t off is depicted in accordance with equations (1) and (2).

[0070] In some applications, it can not be convenient to directly measure t off . However, the value of t off may be related to other parameters that are more easily measured, such as but not limited to the battery voltage V bat .

[0071] As an illustration in the case of a non-limiting design of the charging circuit 102 in Figure 2 , t off may be related to V bat as follows:

[0072]

[0073] Combining equations (1) through (3), one can write:

[0074]

[0075] Figure 6 A plot of the average current as a function of t on and V bat is shown for selected conditions of L and T (e.g., L = 150 μΗ and T = 200 μβ) in accordance with one or more embodiments of the present disclosure.

[0076] Equations (1) through (4) can be valid only under DCM. When t on and t off ​When the current exceeds the switching cycle, the charging circuit 102 is in CCM, and the average current can be determined using conventional techniques.

[0077] When measuring the average current based on the S / H signal 404 under DCM (e.g., using such...) Figure 1 The implementation of the first ADC channel 106-1 depicted in the text and the direct measurement results based on current (e.g., using...) Figure 1 In the implementation of the second ADC channel 106-2 (described in the figure) for measuring the average current, it may be desirable to ensure a smooth transition when switching between the two measurements. Such a smooth transition can be provided by any suitable technique.

[0078] In some implementations, the output current measurement is based on a weighted combination of measurement techniques under at least some conditions (e.g., in the transition region).

[0079] For example, the output current I charger It can be provided as:

[0080] I charger =G·I Direct +(1-G)·I S / H (5)

[0081] Among them, I Direct Based on direct measurements of current (e.g., using methods such as...) Figure 1 The second ADC channel (106-2) depicted in the text, I S / H Measurement results based on S / H signal 404 (e.g., using, as...) Figure 1 The first ADC channel (106-1) is described in the figure, and G is the weight.

[0082] The weight (G) can be a constant or a function of another parameter. For example, Figure 7 Weights (G) as a function of duty cycle are shown in one or more embodiments of this disclosure. In some cases, the duty cycle can be used to determine when the charging circuit 102 is in DCM or CCM. For example, when the duty cycle exceeds a certain value (e.g., the battery voltage (V)). bat ) and source voltage (V DC CCM may occur when the ratio of ) is )). Figure 7 In this configuration, when the duty cycle is below the transition region 702 (e.g., corresponding to DCM), the weight (G) is 0; when the duty cycle is above the transition region 702, the weight (G) is 1; and within the transition region 702 (e.g., corresponding to CCM), the weight (G) varies linearly between 0 and 1. In this way, when in DCM, I can be determined based on the S / H signal 404. chargerthe value of I when in CCM is determined directly based on the current charger the value of I when in CCM is determined directly based on the current charger the value of I when in CCM is determined directly based on the current

[0083] It should be appreciated that Figure 7 are provided for illustrative purposes only and should not be construed as limiting the scope of the disclosure. For example, the transition region 702 can have any width. As another example, the transition region 702 can have any monotonic transition between 0 and 1, and need not be linear. As another example, the weight G can be a function that varies monotonically over the entire duty cycle range. As another example, the weight (G) can be a function of another parameter, and is not limited to duty cycle.

[0084] Reference is now made to Figure 8 , Figure 8 is a flowchart illustrating steps performed in a method 800 for monitoring current in a charging circuit, in accordance with one or more embodiments of the present disclosure. Applicant notes that the embodiments and enabling techniques previously described herein in the context of the current monitoring system 100 should be interpreted to extend to the method 800. For example, the processor 110 in the controller 108 of the current monitoring system 100 can execute program instructions that cause the processor 110 to implement any of the steps of the method 800, either directly or indirectly (e.g., by generating control signals for controlling external components and / or additional components of the current monitoring system 100). Moreover, although various steps of the method 800 are described herein with respect to the current monitoring system 100. This is merely illustrative, and the method 800 is not limited to the architecture of the current monitoring system 100.

[0085] In some embodiments, the method 800 includes a step 802 of generating a S / H signal (e.g., the S / H signal 404) corresponding to a peak value of current in the charging circuit 102 over a switching period (T) of the charging circuit 102. The S / H signal can be generated using any technique known in the art, including but not limited to a S / H circuit (e.g., the S / H circuit 104).

[0086] In some embodiments, the method 800 includes a step 804 of sampling the S / H signal with a first analog-to-digital channel (ADC channel). The S / H signal can be sampled by the first ADC channel at any frequency. It is contemplated herein that sampling the S / H signal can generate at least one sample corresponding to the peak value of current in the charging circuit 102 over the switching period.

[0087] In some implementations, the method 800 includes a step 806 of sampling the current in the charging circuit with the second ADC channel. For example, the current in the charging circuit can be captured with a current transducer.

[0088] In some implementations, the method 800 includes a step 808 of determining the average current of the charging circuit based on the first ADC channel when the charging circuit 102 is operating in the discontinuous conduction mode. In some implementations, the method 800 includes a step 810 of determining the average current of the charging circuit 102 based on the second ADC channel when the charging circuit is operating in the continuous conduction mode. In this way, a measurement of the average current of the charging circuit 102 can be generated regardless of the mode of operation. Under CCM, the average current can be generated based on direct sampling of the current in the charging circuit 102, while under DCM the average current can be determined based on the S / H signal (and possibly additional parameters of the current waveform that can be known or have been measured).

[0089] Reference is now made generally to Figures 1 to 8 It should be appreciated that reference to a measurement of current within the charging circuit 102 is not strictly limiting. Rather, the spirit and scope of the present disclosure extends to a measurement of a signal indicative of or otherwise related to current within the charging circuit 102. For example, the second ADC channel 106-2 can capture and sample a voltage signal that can be indicative of current or that can otherwise have a characteristic that is proportional to current. Similarly, the S / H signal 404 (e.g., sampled by the first ADC channel 106-1) can provide a value that is associated with or proportional to peak current within a switching period.

[0090] The herein described subject matter sometimes illustrates different components contained within, or connected with, other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespective of architectures or intermediate components. Likewise, any two components so associated can also be viewed as being "connected" or "coupled" to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "couplable" to each other to achieve the desired functionality. Specific examples of couplable include but are not limited to physically interactable and / or physically interacting components and / or wirelessly interactable and / or wirelessly interacting components and / or logically interactable and / or logically interacting components.

[0091] It is believed that the present disclosure and many of its attendant advantages will be understood by the forgoing description, and it will be apparent that various changes can be made in the form, construction and arrangement of the components without departing from the disclosed subject matter or without sacrificing all of its material advantages. The form described is merely exemplary and is not intended to limit the scope of the claims appended hereto. Additionally, it is understood that the application is defined by the claims appended hereto.

Claims

1. A current monitoring system, comprising: The S / H circuit (sample and hold circuit) is configured to generate an S / H signal, wherein the S / H signal corresponds to the peak value of the current in the charging circuit during the switching cycle of the charging circuit; The first ADC channel (analog-to-digital channel) is used to sample the S / H signal; A second ADC channel is configured to sample the current in the charging circuit; and A controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: When the charging circuit is operating in discontinuous conduction mode, the average current of the charging circuit is determined based on the first ADC channel; and When the charging circuit is operating in continuous conduction mode, the average current of the charging circuit is determined based on the second ADC channel.

2. The current monitoring system according to claim 1, wherein, The program instructions are also configured to cause the one or more processors to: Generate control signals for controlling one or more switches in the charging circuit.

3. The current monitoring system according to claim 1, wherein, The charging circuit includes: Battery charging circuit.

4. The current monitoring system according to claim 3, wherein, The battery charging circuit is integrated into the uninterruptible power supply device.

5. The current monitoring system according to claim 1, wherein, The sample-and-hold circuit includes one or more capacitors configured to hold a charge corresponding to the peak value of the current in the charging circuit during the switching cycle.

6. The current monitoring system according to claim 1, wherein, Determining the average current of the charging circuit based on the first ADC channel when the charging circuit is operating in the discontinuous conduction mode includes: The average current of the charging circuit is determined based on the first ADC channel and one or more additional characteristics of the current in the charging circuit.

7. The current monitoring system according to claim 6, wherein, The one or more additional characteristics of the current in the charging circuit include at least one of the following: The switching cycle of the charging circuit, the duty cycle of the charging circuit's conduction mode relative to the switching cycle, or the peak value of the current within the switching cycle according to the S / H signal.

8. The current monitoring system according to claim 6, wherein, The charging circuit includes a battery charging circuit, wherein the one or more additional characteristics of the current in the charging circuit include at least one of the following: The switching cycle of the charging circuit, the duty cycle of the charging circuit's conduction mode relative to the switching cycle, the peak value of the current during the switching cycle according to the S / H signal, the voltage of the battery being charged by the charging circuit, or the inductance of the inductor in the charging circuit.

9. A current monitoring method, comprising: An S / H signal is generated using an S / H circuit (sample and hold circuit), which corresponds to the peak value of the current in the charging circuit during the switching cycle of the charging circuit. The S / H signal is sampled using the first ADC channel (analog-to-digital channel); The current in the charging circuit is sampled using the second ADC channel; When the charging circuit is operating in discontinuous conduction mode, the average current of the charging circuit is determined based on the first ADC channel; as well as When the charging circuit is operating in continuous conduction mode, the average current of the charging circuit is determined based on the second ADC channel.

10. The current monitoring method according to claim 9, further comprising: Generate control signals for controlling one or more switches in the charging circuit.

11. The current monitoring method according to claim 9, wherein, The charging circuit includes: Battery charging circuit.

12. The current monitoring method according to claim 11, wherein, The battery charging circuit is integrated into the uninterruptible power supply device.

13. The current monitoring method according to claim 9, wherein, The sample-and-hold circuit includes one or more capacitors configured to hold a charge corresponding to the peak value of the current in the charging circuit during the switching cycle.

14. The current monitoring method according to claim 9, wherein, Determining the average current of the charging circuit based on the first ADC channel when the charging circuit is operating in the discontinuous conduction mode includes: The average current of the charging circuit is determined based on the first ADC channel and one or more additional characteristics of the current in the charging circuit.

15. The current monitoring method according to claim 14, wherein, The one or more additional characteristics of the current in the charging circuit include at least one of the following: The switching cycle of the charging circuit, the duty cycle of the charging circuit's conduction mode relative to the switching cycle, or the peak value of the current within the switching cycle according to the S / H signal.

16. The current monitoring method according to claim 14, wherein, The charging circuit includes a battery charging circuit, wherein the one or more additional characteristics of the current in the charging circuit include at least one of the following: The switching cycle of the charging circuit, the duty cycle of the charging circuit's conduction mode relative to the switching cycle, the peak value of the current during the switching cycle according to the S / H signal, the voltage of the battery being charged by the charging circuit, or the inductance of the inductor in the charging circuit.

17. An uninterruptible power supply device, comprising: A charging circuit, used to charge the battery; The S / H circuit (sample and hold circuit) is configured to generate an S / H signal, wherein the S / H signal corresponds to the peak value of the current in the charging circuit during the switching cycle of the charging circuit; The first ADC channel (analog-to-digital channel) is used to sample the S / H signal; A second ADC channel is configured to sample the current in the charging circuit; and A controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: When the charging circuit is operating in discontinuous conduction mode, the average current of the charging circuit is determined based on the first ADC channel; and When the charging circuit is operating in continuous conduction mode, the average current of the charging circuit is determined based on the second ADC channel.

18. The uninterruptible power supply device according to claim 17, wherein, The program instructions are also configured to cause the one or more processors to: Generate control signals for controlling one or more switches in the charging circuit.

19. The uninterruptible power supply device according to claim 17, wherein, Determining the average current of the charging circuit based on the first ADC channel when the charging circuit is operating in the discontinuous conduction mode includes: The average current of the charging circuit is determined based on the first ADC channel and one or more additional characteristics of the current in the charging circuit.

20. The uninterruptible power supply device according to claim 19, wherein, The one or more additional characteristics of the current in the charging circuit include at least one of the following: The switching cycle of the charging circuit, the duty cycle of the charging circuit's conduction mode relative to the switching cycle, the peak value of the current during the switching cycle according to the S / H signal, the voltage of the battery being charged by the charging circuit, or the inductance of the inductor in the charging circuit.

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