Doorbell system with pulse-driven boost rectifier

Patent metadata

Field	Value
Publication number	US-10692334-B2
Application number	US-201916389515-A
Country	US
Kind code	B2
Filing date	Apr 19, 2019
Priority date	Jun 29, 2018
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

In some embodiments, a power supply in a doorbell system includes a boost rectifier circuit with a plurality of active devices arranged in a bridge topology that are configured to receive an AC input voltage, generate a DC output voltage by rectifying the AC input voltage, drive an electric load using the rectified DC voltage, and boost an amplitude of the AC input voltage. Two of the plurality of active devices in the boost rectifier circuit may be pulse driven and can control an operation of a mechanical or digital chime device. The chime device can include a solenoid and the boost rectifier circuit may utilize the solenoid as an energy storage element to facilitate the boosting of the amplitude of the AC input voltage. The boost rectifier circuit may boost the AC input voltage by at least a multiplication factor of two.

First claim

The invention claimed is:

1. A method of operating a boost rectifier circuit of a doorbell system, the method comprising:
receiving measurement data corresponding to a measurement of an AC current signal driving an inductor of the doorbell system, the inductor coupled to an input of the boost rectifier circuit,
wherein the inductor is driven by an AC input voltage, and
wherein the inductor is operating as an energy storage element configured to facilitate the boosting of an amplitude of the AC input voltage by the boost rectifier circuit; and

dynamically modifying a boosting profile of the AC input voltage based on:
the measured AC current signal passing through the inductor; and
an amplitude of the AC input voltage,

wherein the boosting profile pulse shapes the AC current signal driving the inductor from a sinusoidal current waveform to a substantially square-wave current waveform.

2. The method of claim 1 wherein the pulse shaping of the AC current signal into a square-wave current waveform causes a reduction in a maximum current of the AC current signal and a reduction in a transition time between peaks of different phases of the AC current signal.

3. The method of claim 2 wherein dynamically modifying the boosting profile of the AC input voltage further includes:
applying a pulsed voltage at inputs of the boost rectifier circuit; and
generating a charge/discharge ramp for each cycle of the AC input voltage based on the pulsed voltage,
wherein the charge/discharge ramp affects the boosting profile of the AC input voltage.

4. The method of claim 3 wherein the charge ramp corresponds to periods of time when the pulsed voltage is on, wherein the discharge ramp corresponds to periods of time when the pulsed voltage is off, and wherein a ratio of charge-to-discharge periods defines an operational duty cycle for the boost rectifier circuit.

5. The method of claim 4 wherein the pulsed voltage is on during each phase of the AC input voltage while the measured AC current signal through the inductor is below a threshold current value, and
wherein the pulsed voltage is off during each phase of the AC input voltage while the measured AC current signal driving the inductor is at or above the threshold current value.

6. The method of claim 4 wherein a pulse-width modulator (PWM) circuit controlled by one or more processors applies the pulsed voltage at the input of the boost rectifier circuit.

7. The method of claim 6 further comprising:
dynamically setting a current limit threshold for the AC current signal based on a current power requirement of a system load;
comparing the current limit threshold with the AC current signal;
generating a corresponding comparator output signal; and
adjusting the duty cycle of the pulsed input voltage based on the comparator output signal.

8. The method of claim 7 wherein a digital-to-analog converter (DAC) performs the dynamically setting the current limit threshold,
wherein a comparator circuit performs the comparing the current limit threshold with the AC current signal and generates the corresponding comparator output signal, and
wherein the PWM circuit performs the adjusting the duty cycle of the pulsed input voltage based on the comparator output signal.

9. The method of claim 1 wherein the boost rectifier circuit is configured to drive a battery charging circuit for a battery system configured to provide power to an electric load.

10. The method of claim 1 wherein the inductor is a solenoid of a doorbell chime circuit of the doorbell system.

11. A doorbell system comprising:
one or more processors; and
one or more non-transitory computer-readable storage mediums that include instructions configured to cause one or more processors to perform operations including:
receiving measurement data corresponding to a measurement of an AC current signal driving an inductor of the doorbell system, the inductor coupled to an input of a boost rectifier circuit,
wherein the inductor is driven by an AC input voltage, and
wherein the inductor is operating as an energy storage element configured to facilitate the boosting of an amplitude of the AC input voltage by the boost rectifier circuit; and

dynamically modifying a boosting profile of the AC input voltage based on:
the measured AC current signal passing through the inductor; and
an amplitude of the AC input voltage,

wherein the boosting profile pulse shapes the AC current signal driving the inductor from a sinusoidal current waveform to a substantially square-wave current waveform.

12. The doorbell system of claim 11 wherein the pulse shaping of the AC current signal into a square-wave current waveform causes a reduction in a maximum current of the AC current signal and a reduction in a transition time between peaks of different phases of the AC current signal.

13. The doorbell system of claim 12 wherein dynamically modifying the boosting profile of the AC input voltage further includes:
applying a pulsed voltage at inputs of the boost rectifier circuit; and
generating a charge/discharge ramp for each cycle of the AC input voltage based on the pulsed voltage,
wherein the charge/discharge ramp affects the boosting profile of the AC input voltage.

14. The doorbell system of claim 13 wherein the charge ramp corresponds to periods of time when the pulsed voltage is on, wherein the discharge ramp corresponds to periods of time when the pulsed voltage is off, and wherein a ratio of charge-to-discharge periods defines an operational duty cycle for the boost rectifier circuit.

15. The doorbell system of claim 14 wherein the pulsed voltage is on during each phase of the AC input voltage while the measured AC current signal through the inductor is below a threshold current value, and
wherein the pulsed voltage is off during each phase of the AC input voltage while the measured AC current signal driving the inductor is at or above the threshold current value.

16. The doorbell system of claim 14 wherein a pulse-width modulator (PWM) circuit controlled by one or more processors applies the pulsed voltage at the input of the boost rectifier circuit.

17. The doorbell system of claim 16 wherein the one or more non-transitory computer-readable storage mediums further include instructions configured to cause one or more processors to perform operations including:
dynamically setting a current limit threshold for the AC current signal based on a current power requirement of a system load;
comparing the current limit threshold with the AC current signal;
generating a corresponding comparator output signal; and
adjusting the duty cycle of the pulsed input voltage based on the comparator output signal.

18. The doorbell system of claim 17 wherein a digital-to-analog converter (DAC) performs the dynamically setting the current limit threshold,
wherein a comparator circuit performs the comparing the current limit threshold with the AC current signal and generates the corresponding comparator output signal, and
wherein the PWM circuit performs the adjusting the duty cycle of the pulsed input voltage based on the comparator output signal.

19. The doorbell system of claim 11 wherein the boost rectifier circuit is configured to drive a battery charging circuit for a battery system configured to provide power to an electric load.

20. The doorbell system of claim 11 wherein the inductor is a solenoid of a doorbell chime circuit of the doorbell system.

Assignees

• Logitech Europe Sa

Inventors

• Long John M
• Reckless Jonathan
• Rosenberg Aron

Classifications

• G10K1/064 Primary

  Operating or striking mechanisms therefor · CPC title

• H02M1/4233

  using a bridge converter comprising active switches · CPC title

• H02M1/0085

  Partially controlled bridges · CPC title

• G08B3/10 Primary

  using electric transmission; using electromagnetic transmission · CPC title

• Y02B70/10

  Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes · CPC title