Stability enhancement of rectifiers using closed loop control

Abstract

The present disclosure relates to rectifier stability enhancement using closed loop control. A system and method for monitoring a signal quality metric coupled with closed loop control improves rectifier signal quality and stability. The closed loop control passes the metric through a high pass filter and captures an error value. This signal is then passed to a controller to adjust rectifier settings. The measured signal is used in ASK demodulation, etc., where the derived signal quality can be V RECT , F CLK , network coil measurement. The controller identifies noise levels and noise types in real time and sets parameters of the rectifier to maintain system stability. The controller can set baud rates and preamble thresholds in a wireless power transfer system in response to the identified noise levels and types.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to rectifier stability enhancement using closed loop control. BACKGROUND

[0002] Existing wireless power transfer systems are typically configured according to a set of parameters with little or no ability to dynamically adjust. As wireless power transfer is implemented to support a wider set of operating conditions (e.g., power levels, frequencies, enhanced modes, etc.), the likelihood of interference and system instability increases. In some instances, rectifiers can be placed in a mode that makes the overall system less stable. It is therefore advantageous to have the ability to monitor the stability of the rectifier.

[0003] The stability of the rectified voltage (V RECT ) in a wireless power transfer system impacts various aspects of overall system quality and stability. When a rectifier becomes unstable, V RECT exhibits ripple / oscillation. The oscillation degrades communication and efficiency. Existing solutions for rectifier stability require coil networks with narrow operating ranges and very fast comparators.

[0004] It is sometimes desirable to change the rectifier mode based on a metric such as V RECT , noise level, other noise characteristics, etc. A controller can change modem behavior based on noise characteristics. The system can include separate modems for frequency shift keying (FSK) and amplitude shift keying (ASK), and the controller can determine which modem to use based on noise characteristics. It is therefore useful to accurately measure and characterize noise. The characterization of noise defines the metric that is used by the controller to make decisions.

[0005] It would be advantageous to have a rectifier that monitors signal quality and uses that information to change system settings to enhance system performance. SUMMARY

[0006] In one aspect, embodiments of the inventive concept disclosed herein relate to a system and method for monitoring V RECT coupled with closed loop control to improve rectifier signal quality and stability. The closed loop control passes V RECT through a high pass filter and captures an error value. The error value is then passed to a controller to adjust the closed loop V RECT control current.

[0007] In another aspect, the controller monitors various aspects of rectifier signal quality including V RECT fidelity, carrier frequency oscillation signal (F CLK) fidelity and coil or series capacitance fidelity (e.g., for amplitude shift keying (ASK) demodulation). The controller identifies noise levels and noise types in real time and sets parameters of the rectifier to maintain system stability.

[0008] In another aspect, the controller can set a baud rate and a preamble threshold in a wireless power transfer system in response to the identified noise level and type.

[0009] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the scope of the claims. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the inventive concepts disclosed herein and, together with the general description, serve to explain principles. BRIEF DESCRIPTION OF DRAWINGS

[0010] Many advantages of embodiments of the inventive concepts disclosed herein will be better understood by referring to the accompanying drawings, in which:

[0011] Figure 1 A block diagram of a system according to an exemplary embodiment is shown;

[0012] Figure 2 A plot of rectifier output under various conditions is shown;

[0013] Figure 3 A plot of rectifier output under various conditions is shown;

[0014] Figure 4 A plot of rectifier output under various conditions is shown;

[0015] Figure 5 A plot of rectifier output under various conditions is shown;

[0016] Figure 6 A block diagram of a system according to an exemplary embodiment is shown;

[0017] Figure 7 A block diagram of a system according to an exemplary embodiment is shown;

[0018] Figure 8 A block diagram of a system according to an exemplary embodiment is shown; and

[0019] Figure 9 A block diagram of a system according to an exemplary embodiment is shown. DETAILED DESCRIPTION

[0020] Before various embodiments of the inventive concepts disclosed herein are explained in detail, it is to be understood that the inventive concepts are not limited in its applications to the details of construction or the arrangements of components or steps or methods set forth in the following description or illustrated in the drawings. In the following detailed description of embodiments of the inventive concepts, numerous specific details are set forth in order to provide a more thorough understanding of the inventive concepts. However, it will be apparent to one of ordinary skill in the art having the benefit of the present disclosure that the inventive concepts disclosed herein can be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the present disclosure. The inventive concepts disclosed herein are capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

[0021] As used herein, letters following reference numbers are intended to refer to embodiments of features or elements that can be similar to, but not necessarily identical to, previously described elements or features with the same reference number (e.g., 1, 1a, 1b). Such shorthand notation is used for convenience purposes only, and should not be interpreted as limiting the inventive concepts disclosed herein in any way, unless explicitly stated to the contrary.

[0022] Further, unless explicitly stated to the contrary, “or” means an inclusive or and not an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

[0023] Additionally, the use of “a” or “an” is employed to describe elements and components of the embodiments of the inventive concepts. This is done merely for convenience and to give a general sense of the inventive concepts’ scope and should be read to include one or at least one, and the singular also includes the plural, unless it is obvious that it is meant otherwise.

[0024] Furthermore, while various components can be depicted as being directly connected, direct connection is not required. Components can be in data communication with intermediary components not shown or described.

[0025] Finally, as used herein, any reference to “one embodiment” or “some embodiments” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the inventive concepts disclosed herein. The appearances of the phrase “in at least one embodiment” in the specification in various places does not necessarily make reference to the same embodiment. Embodiments of the inventive concepts disclosed can include one or more of the features described herein, or any combination or sub-combination of two or more of such features.

[0026] Broadly speaking, embodiments of the inventive concepts disclosed herein relate to a system and method for monitoring a measurement signal quality metric coupled to closed-loop control to improve rectifier signal quality and stability. The rectifier can be any device that converts alternating current (AC) to direct current (DC). The rectifier can be (but is not limited to) an uncontrolled rectifier or a controlled rectifier. Closed-loop control allows the metric to pass through a high-pass filter and captures the error value. The filter can be any device that allows certain frequencies to pass while blocking others (e.g., a high-pass filter or a low-pass filter). For example, a high-pass filter can allow frequencies above a certain frequency to pass while blocking frequencies below a cutoff frequency. This signal can then be passed to a controller to adjust the rectifier settings for closed-loop control. The measured signal (e.g., where the signal quality varies from V...) RECT F CLK (Derived from network coil measurements, etc.) It can be used for ASK demodulation, etc. The controller can identify noise levels and types in real time and set rectifier parameters to maintain system stability. The controller can set the baud rate and preamble threshold in the wireless power transmission system in response to the identified noise levels and types.

[0027] refer to Figure 1 The diagram illustrates a block diagram of a system according to an exemplary embodiment. The system (e.g., a wireless power delivery system) may include a rectifier 100 that receives a phase-shifted alternating current (AC) signal and outputs V... RECT This refers to direct current (DC) voltage. Rectifier 100 may include a plurality of field-effect transistors (FETs) switched via a gate drive circuitry or logic. FETs can be any type of transistor that uses an electric field to control the flow of current in a semiconductor. Field-effect transistors may be (but are not limited to) junction field-effect transistors (JFETs) or insulated-gate field-effect transistors (IGFETs). For example, each FET may be switched via a corresponding current comparator configured to respond to a rectifier turn-off threshold current (I0). LIM And switch the corresponding FET; I LIM The comparator can be specific to each FET, specific to a set of low-side and high-side FETs, or substantially the same for each FET. A comparator can be any device (e.g., a circuit or a component of a circuit) having two independent voltage or current inputs and an output based on whichever input has the larger value. For example, if the first input is greater than the second input, the comparator can output 1. Conversely, if the second input is greater than the first input, the comparator can output 0. The comparator can include a high-gain differential amplifier. Furthermore, the output of the comparator can act as a switch for a circuit component (e.g., a FET) by, for example, providing a gate voltage to or turning off the gate voltage of a FET.

[0028] A wireless power transfer system can establish a data communication link via a modem that sends and receives data over the same electronic connection in addition to sending power from a transmitter to a receiver. A modem can be any device (e.g., component of a circuit) that includes modulation and demodulation capabilities. For example, at one end of the modem, the modem can accept digital data and convert (e.g., modulate) the digital data into an analog signal. Conversely, at the other end of the modem, the analog signal can be converted (e.g., demodulated) and digital data can be output. The modem can be, but is not limited to, a half-duplex or full-duplex modem. Existing standards for wireless power are cumbersome because any type of communication error triggers a shutdown and restart of the wireless power link. Each time a packet is lost, the system stops charging completely, recovers to a start-up process, and restarts the wireless power session.

[0029] F CLK Fidelity can indicate a fault in the system. Sometimes F CLK is noisy because errors in the coil network 108 cause excessive ringing or some other anomaly. The coil network can be any inductor or multiple inductors inserted into an electronic circuit to increase the inductance of the circuit. In at least one embodiment, the system can include a controller 104 (e.g., a programmable processor, a gate array, or other logic circuitry) configured to receive F CLK and determine a fidelity value about the individual oscillators. An oscillator can be any electronic circuit that produces a periodic and oscillating signal. The signal can be, but is not limited to, a sine wave, a square wave, or a triangle wave. The oscillator can be, but is not limited to, a low frequency oscillator, a radio frequency (RF oscillator), or a high frequency oscillator. Alternatively or additionally, F CLK Fidelity can be measured by referencing a known clock to measure the turn-on and turn-off times of components (e.g., FETs) in the rectifier 100. The controller 104, which can be configured as a proportional-integral (PI) controller, can periodically accumulate the measurements over some interval of time (e.g., a clock cycle). In at least one embodiment, the measurements can be every millisecond, every 10 milliseconds, etc. While specific embodiments refer to a PI controller, it can be appreciated that other embodiments are contemplated; for example, the controller 104 can be configured as a proportional-integral-derivative (PID) controller. Furthermore, while specific embodiments refer to a single controller 104, multiple controllers 104 are contemplated that can operate individually or in conjunction to perform the functions described herein.

[0030] Alternatively, the measurements can be asynchronous or event-triggered. In at least one embodiment, the controller 104 can detect an event that causes an interrupt. The controller 104 can then take F CLKMeasurement of fidelity. In another example, during modem operation, there can be a known window of time in which FSK messages are expected to be received and the controller 104 negotiates the baud rate. It would be advantageous to measure the noise prior to the negotiation.

[0031] Any mode change in the rectifier 100 can be sensitive to network parameters. Whenever a mode change occurs, the controller 104 can measure the signal quality and ensure that the rectifier 100 reacts correctly; otherwise, the controller 104 can revert to the previous known stable mode. For example, the rectifier 100 can be configured for continuous conduction mode, in which the behavior of a state machine 106 (e.g., a sequential circuit (e.g., a circuit that operates based on a particular sequence of events)) in the rectifier 100 is programmed. If the value in a register programmed into the state machine 106 does not match the frequency of the carrier signal, the rectifier 100 can become unstable. It would be advantageous to quickly identify such conditions. In this case, the controller 104 can perform F CLK Measurement of fidelity to verify rectifier stability. In the event that the controller 104 determines that the rectifier is unstable, it can shut off the continuous conduction mode. Without mechanisms for monitoring the signal quality, such as described herein, the continuous conduction mode can be difficult to implement. In the event that the rectifier 100 switches into and out of the continuous conduction mode, the F CLK The fidelity measurement can indicate a particular type of instability.

[0032] Rectifier stability can refer to the output of the rectifier 100. The voltage V RECT may not be strictly DC; it can include AC components and oscillations (e.g., noise). In at least one embodiment, V RECT may be processed via the controller 104. The controller 104 can include a slope detector (e.g., a high frequency detector). The slope detector can determine the slope or first derivative of V RECT , which can be used to adjust the boost of the rectifier 100. In at least one embodiment, the controller 104 can measure the noise on V RECT and feed the noise back into the rectifier 100 in a closed loop. Such closed loop feedback can be used as an adaptive noise filter, in which the controller 104 measures the offset of the noise and feeds it back into the rectifier 100, thereby attenuating the noise.

[0033] In at least one embodiment, the controller 104 can measure the F CLK fidelity and perform the calculations as described herein in the analog domain (e.g., with reference to an analog oscillator) or the digital domain (e.g., with reference to one or more digital timers). The controller 104 can perform post-processing, such as (but not limited to) calculating the average error, root mean square error, and / or variance.

[0034] In at least one embodiment, the wireless power transfer system can include a filter 102 (e.g., a high-pass filter) configured to extract noise components (e.g., high-frequency oscillations) of the signal V RECT Alternatively or additionally, the filter 102 can receive F CLK and / or coil network 108 measurements. The filtered noise components can be transmitted to the controller 104 and state machine 106, which can adjust the current threshold (I LIM ) in one or more comparators in the rectifier and / or increase the gain of the rectifier 100 based on the filtered noise components. The I LIM adjustment can be limited to a certain predetermined range (e.g., + / - 400 mA).

[0035] In at least one embodiment, the controller 104 monitoring V RECT may identify noise (e.g., ripple oscillations) and adjust the I LIM of one or more comparators of the rectifier 100 to change the threshold for corresponding FET turn-on and turn-off. For example, V RECT may be passed through a high-pass filter 102, such as a 500 kHz filter. The controller 104 (e.g., a PI controller) can identify the instantaneous, average, and / or root-mean-square noise level from the high-frequency components of V RECT and then calculate the I LIM threshold as a function of the high-frequency components. In at least one embodiment, the controller 104 can be configured according to a machine learning algorithm to determine the I LIM threshold based on inputs including (but not limited to) the high-frequency components of V RECT The controller 104 can then deliver the new I LIM threshold to the comparators, either directly or via the state machine 106. Previous mechanisms of adjusting I LIM via an open-loop approach can prove to be unstable. In contrast, a mechanism based on a closed-loop controller can eliminate system oscillations.

[0036] In at least one embodiment, the controller 104 can receive signals to turn on and turn off measurement accumulation, reset integral error values, dump integral error values after a predetermined amount of integration, etc. The controller 104 can be individually controllable with respect to F CLK fidelity and V RECT fidelity measurements.

[0037] In at least one embodiment, the controller 104 can receive signals from the output current sensor (I SNS)110 receive output current measurements. In addition, the system can include a linear voltage regulator, such as a low-dropout regulator (LDR) 112. The output current sensor can be any device that converts current to an output voltage. The low-dropout regulator can be any device that regulates the output voltage in a DC circuit.

[0038] Referring Figure 2 , a graph of rectifier output under various conditions is shown. In one example simulation, the coil parameters, comparator delay, and system input values can tend to produce oscillations 200. A load 204 can dampen oscillations 206, however, a controller according to an exemplary embodiment can turn on 202 at startup or at some later time and keep oscillations 200 within certain bounds even when there is no load or minimal load. Without a controller, the ripple oscillations on V RECT can exceed one volt 208; a 50 to 150 millivolt ripple is typical in a stable rectifier due to switching.

[0039] Referring Figures 3 to 5 , a graph of rectifier output under various conditions is shown. The simulation demonstrates that according to an exemplary embodiment, under worst-case stability conditions, with the controller enabled, the ripple can be well controlled. Also, under typical conditions, with slow line stepping (e.g., as in Figure 3 and 4 ) or fast line stepping (e.g., as in Figure 5 ), the ripple can be maintained within acceptable limits and can be adjusted without introducing instability. LIM .

[0040] Referring Figure 6 , a block diagram of a system according to an exemplary embodiment is shown. The system (e.g., a wireless power transfer system (e.g., as described with respect to Figure 1 ) can include a rectifier 600 that receives a phase-offset AC signal and outputs V RECT . The rectifier 600 can include a plurality of FETs that can be switched via gate drive circuitry or logic (e.g., current comparators configured to switch corresponding FETs based on I LIM .

[0041] A wireless power transfer system can establish a data communication link via a modem that sends and receives data over the same electronic connection in addition to sending power from a transmitter to a receiver. Whenever a rectifier receives a power signal, the rectifier can derive a clock F CLK from the power signal and can use the clock for FSK decoding as an accurate clock reference for baud rate, clock error correction, etc. It can be desirable to derive F CLKFidelity to determine if the noise on the clock is allowing the clock to be usable, what type of FSK front end filtering is needed, improved ASK / FSK modem thresholds based on the noise, what type of modem to use, etc.

[0042] Existing standards for wireless power are cumbersome because any type of communication error triggers a shutdown and restart of the wireless power link. Whenever a packet is lost, the system stops charging completely, recovers to the startup process, and restarts the wireless power session. In at least one embodiment, the system can, but is not limited to, set system parameters (e.g., ASK parameters (e.g., preamble threshold or baud rate)), frequency band, or use an out-of-band communication protocol (e.g., Bluetooth) based on one or more signal quality metrics to balance the desired communication rate with a low rate of restart occurrences. The signal quality metrics can include, but are not limited to, F CLK Fidelity, V RECT Fidelity and ASK modulation fidelity.

[0043] In at least one embodiment, a controller 604 (e.g., programmable processor, gate array, or other logic circuitry) can be configured to receive F CLK and determine a fidelity value, as described herein. Further, a filter 602 (e.g., high pass filter) can extract the noise component (e.g., high frequency oscillations) of the V RECT signal.

[0044] F CLK Fidelity can be particularly useful for determining baud rate, optimizing front end modems, performing built-in self-tests, etc. In a wireless power transfer system, F CLK fidelity and V RECT Fidelity can be useful for identifying when the system is exceeding some specification boundary. The F CLK fidelity values and V RECT fidelity values can be delivered to an algorithm 606 that is configured to associate such fidelity values with system parameters 614. The algorithm 606 can comprise one or more lookup tables, mathematical function associations, trained machine learning systems, etc. The algorithm 606 can then apply the identified set of desired system parameters 614; including in-channel or out-of-channel communication protocols, ASK and FSK preamble thresholds, modem baud rates, etc.

[0045] Existing wireless power transfer systems have a fixed baud rate for FSK. Embodiments of the present disclosure enable a variable and fast baud rate. The controller 604 that measures the signal quality metrics and the corresponding algorithm 606 can determine an increased baud rate to be applied to the system.

[0046] For ASK communication, the system can include a decoding modem that listens for the received power signal for a preamble. When the preamble threshold is not set correctly, the system can determine that a packet is coming and prepare the modem and central processing unit (CPU), which wastes power. Furthermore, if the system starts a false preamble when looking for a packet, and then receives the actual preamble, the false start can cause the packet to be lost. Alternatively, without the correct threshold, the system can completely miss the packet, which is a particular problem in wireless power transfer.

[0047] In at least one embodiment, when a preamble is received, the modem or controller 604 and algorithm 606 can determine a threshold for detection. It can be difficult to determine the correct preamble threshold a priori; therefore, the controller 604 can measure the noise on the ASK signal before a new preamble is received, and the algorithm 606 can determine an appropriate threshold; this threshold can then be set as a system parameter 614. In at least one embodiment, the controller 604 can utilize a predefined model within the system in a measurement mode to extract signal quality metrics, including F CLK Fidelity and V RECT Fidelity. For example, when no modem data is being transmitted, logic within the modem or via the controller 604 of the modem can monitor the noise level 608 and corresponding noise type or characteristics on the coil network. The algorithm 606 can use the noise level and type to set system parameters 614 (e.g., preamble threshold for detection, baud rate, etc.). For example, when determining the ASK preamble threshold, existing modem circuitry can be used as a signal quality calculator, or a dedicated block can exist to measure the noise on the coil network 608.

[0048] In at least one embodiment, the controller 604 can receive signals to turn on and off measurement accumulation, reset the integral error value, dump the integral error value after so many integrations, etc. The controller 604 can be individually controllable with respect to the measurement of ASK fidelity. In at least one embodiment, the controller 604 can potentially measure the downconverted ASK signal via the ASK modem; such measurements can identify the magnitude of each channel and accumulate the measurements of these magnitudes. The ASK signal and noise can be directly related to a root mean square calculation of the magnitude measurements. The root mean square value can be used to set the ASK preamble threshold.

[0049] Referring to Figure 7 , a block diagram of a system according to an exemplary embodiment is shown. The system, such as a wireless power transfer system, can include a rectifier 700 with multiple FETs and corresponding drive circuitry or logic.

[0050] In at least one embodiment in which the rectifier 700 includes a state machine 706, one or more timers 714, 716 can control or inform on events in the state machine 706. The timers 714, 716 can be configured for 1 / 2 cycle and / or full cycle on events. With a known input carrier frequency, the timers 714, 716 can force the rectifier 700 to switch according to performance expectations. If a 50% duty cycle is known via a measurement of a signal quality metric as described herein, and oscillations cause on and off periods to shift, the timers 714, 716 can modify the state machine 706 to force the desired on and off timings within a narrower range.

[0051] In at least one embodiment, one or more high frequency timers can measure on, off timings in the rectifier 700 (e.g., when the carrier signal goes high compared to when the carrier signal goes low). When rectifying a carrier signal, the rectifier 700 can use a comparator that measures the duration of on and off periods. The controller 704 can determine the jitter of the FSK based on the measurements CLK For example, the controller 704 (e.g., a PI controller) can perform a root mean square calculation, a deviation calculation, or some other process to approximate the jitter; higher accumulated root mean square error values can indicate higher jitter.

[0052] Jitter can be a useful metric for FSK demodulation. The magnitude of the jitter can be used to determine an appropriate modem type for front-end filtering, modem configuration settings, baud rates for FSK communication, etc. In at least one embodiment, such front-end filtering and baud rates can be determined via a function that relates the settings to the timer output (e.g., instantaneous or integrated values over time). Alternatively or additionally, the controller 704 can employ a trained machine learning algorithm. The controller 704 can then apply such settings to a modem or other data communication hardware.

[0053] Referring to Figure 8 , a block diagram of a system according to an exemplary embodiment is shown. The system (e.g., a wireless power transfer system) can include a rectifier 800 having multiple FETs and corresponding drive circuitry or logic, and a state machine 806 can set and / or adjust features of the rectifier 800 (e.g., I LIM ) based on a signal quality metric from time to time to enhance rectifier stability.

[0054] In at least one embodiment, the controller 804 can determine a maximum baud rate for the FSK based on the noise. The controller 804 can utilize a closed loop algorithm to determine the maximum baud rate based on the mean and variance of the on and off durations (e.g., root mean square and / or deviation as described herein). Further, the controller 804 can interact with the state machine 806 to adjust features of the rectifier that reduce noise, as more fully described herein.

[0055] In at least one embodiment, the controller 804 can enable V RECT The measurement of V is performed through a filter (e.g., a high-pass filter). RECT Fidelity. Accumulated V RECT The high-frequency noise is measured, and the controller 804 can calculate V. RECT The mean, root mean square, variance, etc. A higher V RECT Noise is associated with higher root mean square error values. RECT Measurements can be converted into digital values ​​via an analog-to-digital converter (ADC) 818 for digital integration by a controller 804. An ADC can be any system capable of converting an analog input signal into a digital signal. An ADC is (but is not limited to) a successive approximation (SAR) ADC, a delta-sigma ADC, a dual-slope ADC, a pipelined ADC, or a flash ADC.

[0056] V RECT Fidelity can be useful in determining rectifier stability. A stable rectifier produces a DC output with no or very low high-side frequency content. High-side frequency content may indicate system instability (e.g., coil parameters or load causing instability) and / or that a component has been incorrectly programmed.

[0057] refer to Figure 9 This diagram illustrates a block diagram of a system according to an exemplary embodiment. The system (e.g., a wireless power delivery system) may include a rectifier 900 having multiple FETs and corresponding drive circuitry or logic, and a state machine 906 may periodically set and / or adjust characteristics of the rectifier 900 based on signal quality metrics to enhance rectifier stability. A controller 904 may receive measurements of position within a coil network 908 and record these measurements based on data transmission through the coil network 908. For example, when the carrier signal does not contain any data, the controller 904 may calculate the average and variance and / or series capacitor voltage on the coil network 908 920. When the carrier signal does contain data, the controller 904 may calculate the average and variance (e.g., preamble and / or data packets) on the decoder input 922.

[0058] In at least one embodiment, the controller 904 may include or implement filters (e.g., high-pass filters), ADCs, slope detectors for deriving the slope or first derivative of a carrier signal or a filter component of the carrier signal, down-converters, etc.

[0059] Embodiments of this disclosure achieve closed-loop control of V by measuring the rectifier output and controlling a dynamic buck or boost control signal to adjust the rectifier output voltage. RECTReal-time monitoring to improve rectifier signal quality and stability. Real-time monitoring and control enables wider coil networks and slower rectifier comparators (e.g., smaller area and active power) compared to existing systems.

[0060] It is believed that the inventive concept disclosed herein and many of its attendant advantages will be understood by the fore going description, and it will be apparent that various changes can be made in the form, construction, and arrangement of the components thereof without departing from the scope of the inventive concept disclosed herein or without sacrificing all of its advantages; the individual features shown from various embodiments can be combined in other embodiments. It is intended that all such modifications and variations be included within the scope of the following claims as patently encompassed by the inventive concept disclosed herein. Furthermore, any features disclosed in any individual embodiment can be incorporated into any other embodiment.

Claims

1. A system comprising: A rectifier, comprising: Multiple field-effect transistors (FETs); and Multiple comparators, each configured to switch one or more of the FETs; A high-pass filter configured to extract the noise component of the rectified voltage signal; and At least one controller configured to: Receive oscillation signals; Identify an event as the occurrence of one of a predefined set of events; Determine the fidelity of the oscillating signal associated with the event; The gain value of the rectifier is determined based on the slope of the oscillation signal; Measure the change of the oscillation signal over time; Identify noise in the oscillation signal; and The current threshold I of at least one of the plurality of comparators is adjusted based on the identified noise and the measured changes. LIM .

2. The system of claim 1, wherein the at least one controller is further configured to: At least based on the identified noise, a set of modem configuration settings for establishing a data connection is determined.

3. The system of claim 2, wherein the at least one controller is further configured to determine the frequency shift keying (FSK) front-end filter based at least on the identified noise.

4. The system according to claim 1, wherein: The at least one controller is further configured to identify the event as the occurrence of one of a predefined set of events; and In response to the identified event, the measurement of the change of the oscillation signal over time begins.

5. The system according to claim 4, wherein: The event includes receiving a signal for initiating data communication; and The at least one controller is further configured to: Identify noise in the oscillation signal; and Determine the baud rate for the data communication.

6. A rectifier comprising: Multiple field-effect transistors (FETs); Multiple comparators, each configured to switch one or more of the FETs; Coil network; A high-pass filter configured to extract the noise component of the rectified voltage signal; and At least one controller configured to: Receive signals from one or more locations within the coil network; Determine the state of the received signal to include a request for initiating data communication; In response to determining that the signal does not contain a request for initiating data communication, the voltage value from the signal is accumulated; In response to determining that the signal contains a request for initiating data communication, the decoder input from the signal is accumulated; Identify noise in oscillating signals; Identify an event as the occurrence of one of a predefined set of events; Determine the fidelity of the oscillating signal associated with the event; The gain value of the rectifier is determined based on the slope of the oscillation signal; and One or more data communication settings are determined based on the identified noise and the accumulated decoder input.

7. The rectifier of claim 6, wherein the at least one controller is further configured to: The change of the oscillation signal over time is measured based at least on the accumulated voltage value; and The current threshold I of at least one of the plurality of comparators is adjusted based at least on the measured change. LIM .

8. The rectifier of claim 7, wherein the at least one controller is further configured to adjust the rectifier gain based at least on the measured change.

9. The rectifier of claim 6, wherein the at least one controller is further configured to: Measure the oscillation in the rectified voltage; The current threshold I of at least one of the plurality of comparators is adjusted based at least on the measured oscillation. LIM .

10. The rectifier of claim 9, wherein the at least one controller is further configured to adjust the rectifier gain based at least on the measured oscillation.

11. The rectifier of claim 9, further comprising a filter configured to receive the rectified voltage and generate a signal including the oscillation, wherein the at least one controller is further configured to apply the filtered signal to the rectifier input.

12. A wireless power transmission system, comprising: A rectifier configured to generate a rectified voltage, the rectifier including a plurality of field-effect transistors (FETs) and a plurality of comparators, each comparator being configured to switch one or more of the FETs; A high-pass filter configured to extract the noise component of the rectified voltage signal; At least one controller configured to: Measure the oscillation in the rectified voltage; Identify noise in the rectified voltage; and Identify an event as the occurrence of one of a predefined set of events; Determine the fidelity of the oscillating signal associated with the event; The gain value of the rectifier is determined based on the slope of the oscillation signal; The current threshold I of at least one of the plurality of comparators is adjusted based on the identified noise and the measured oscillation. LIM .

13. The wireless power transmission system of claim 12, further comprising a filter configured to receive the rectified voltage and generate a signal containing the oscillation.

14. The wireless power transmission system of claim 13, wherein the at least one controller is further configured to apply the filtered signal to the rectifier input.

15. The wireless power transmission system of claim 12, wherein the at least one controller is further configured to: Determine the slope of the oscillation; and The boost value of the rectifier is determined at least based on the slope.

16. The wireless power transmission system of claim 12, wherein the at least one controller is further configured to adjust the gain of the rectifier at least based on the oscillation.

17. The wireless power transmission system of claim 12, wherein the at least one controller is further configured to identify the baud rate for data communication based at least on the oscillation.

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