KR-102962744-B1 - APPARATUS AND METHOD FOR TRACKING MAXIMUM POWER

KR102962744B1KR 102962744 B1KR102962744 B1KR 102962744B1KR-102962744-B1

Abstract

A maximum power tracking device and method are disclosed. A maximum power tracking device according to one embodiment comprises an initial capacitor, a charge sharing capacitor connected in parallel with the initial capacitor, a first switch disposed between an energy harvesting power source and the initial capacitor, a second switch disposed between the initial capacitor and the charge sharing capacitor, a third switch disposed between an energy harvesting power source and a comparator, a power comparison circuit including a comparator, a switch capacitor power conversion circuit controlling the initial capacitor, and an energy harvesting power source. In response to a determination of an increase in the initial capacitor at a previous time, the switch capacitor power conversion circuit sets the initial capacitor to the capacitance of the current time, the energy harvesting power source applies a first voltage of the current time determined according to the initial capacitor to the initial capacitor, the energy harvesting power source is opened and the initial capacitor and the charge sharing capacitor are connected in parallel, after which the comparator senses a second voltage of the current time from the initial capacitor or the charge sharing capacitor, and the switch capacitor power conversion circuit sets the initial capacitor to the next time The energy harvesting power source is set to an increased capacitance, and the operating frequency is changed according to the increased initial capacitor to apply a third voltage at the next time to the comparator, and the comparator compares the second voltage and the third voltage to determine whether to increase or decrease the increased initial capacitor.

Inventors

배치성
기형민
윤여훈
이윤명

Assignees

삼성전자주식회사
성균관대학교산학협력단

Dates

Publication Date: 20260508
Application Date: 20201006

Claims (20)

Initial capacitor; A charge-sharing capacitor connected in parallel with the initial capacitor above; A first switch positioned between the energy harvesting power source and the initial capacitor; A second switch disposed between the initial capacitor and the charge-sharing capacitor; A third switch positioned between the energy harvesting power source and the comparator; and Power comparison circuit including the above comparator; A switch capacitor power conversion circuit that controls the initial capacitor; and Including the above energy harvesting power source, In response to the decision to increase the initial capacitor mentioned above at the previous time, The above switch capacitor power conversion circuit sets the initial capacitor to the capacitance of the current time, and The energy harvesting power source applies a first voltage at the current time determined according to the initial capacitor to the initial capacitor, and After the energy harvesting power source is opened and the initial capacitor and the charge sharing capacitor are connected in parallel, the comparator senses the second voltage at the current time from the initial capacitor or the charge sharing capacitor, and The above switch capacitor power conversion circuit sets the initial capacitor to an increased capacitance at the next time, and The above energy harvesting power source is changed according to the operating frequency changed according to the increased initial capacitor to apply a third voltage at the next time to the comparator, and The above comparator compares the second voltage and the third voltage to determine whether to increase or decrease the increased initial capacitor. Maximum power tracking device.
In paragraph 1, The above energy harvesting power source is, Short-circuiting the first switch to apply the first voltage of the current time to the initial capacitor, Maximum power tracking device.
In paragraph 1, The first switch is opened, and the energy harvesting power source is opened, and The second switch is short-circuited so that the initial capacitor and the charge-sharing capacitor are connected in parallel, and The above comparator senses a second voltage at the current time from the initial capacitor or the charge-sharing capacitor, Maximum power tracking device.
In paragraph 1, The above switch capacitor power conversion circuit is, Setting the initial capacitor to the increased capacitance of the next time according to the increase decision of the previous time, Maximum power tracking device.
In paragraph 1, The above comparator is, If the above third voltage is greater than the above second voltage, it is determined to increase the above increased initial capacitor, and If the third voltage is smaller than the second voltage, determining to reduce the increased initial capacitor, Maximum power tracking device.
In paragraph 1, In response to the decision to reduce the initial capacitor mentioned above at the previous time, The above switch capacitor power conversion circuit sets the initial capacitor to the capacitance of the current time, and The above comparator senses a third voltage from an energy harvesting power source determined according to the above initial capacitor, and The above switch capacitor power conversion circuit sets the initial capacitor to a reduced capacitance at the next time, and The above energy harvesting power source is changed according to the operating frequency changed according to the above reduced capacitor to apply a first voltage at the next time to the above reduced initial capacitor, and After the energy harvesting power source is opened and the initial capacitor and the charge sharing capacitor are connected in parallel, the comparator senses a second voltage at the next time from the reduced initial capacitor or the charge sharing capacitor, and The above comparator compares the second voltage and the third voltage to determine whether to increase or decrease the reduced initial capacitor. Maximum power tracking device.
In paragraph 6, The above switch capacitor power conversion circuit sets the above initial capacitor of the next time to the reduced capacitance of the next time according to the reduction determination of the previous time, Maximum power tracking device.
In paragraph 6, The above first switch is short-circuited, and The above energy harvesting power source changes according to the above reduced initial capacitor to apply the above first voltage at the next time to the above initial capacitor, Maximum power tracking device.
In paragraph 6, The first switch is opened, and the energy harvesting power source is opened, and The second switch is short-circuited so that the initial capacitor and the charge-sharing capacitor are connected in parallel, and The above comparator senses the second voltage at the next time of the reduced initial capacitor or the charge-sharing capacitor, Maximum power tracking device.
In paragraph 6, The above comparator is, If the third voltage is greater than the second voltage, it is determined to reduce the reduced initial capacitor, and If the third voltage is smaller than the second voltage, determining to increase the reduced initial capacitor, Maximum power tracking device.
In a method for estimating maximum power in a maximum power tracking device, Step of setting the initial capacitor to the capacitance of the current time; A step of applying a first voltage at the current time to the initial capacitor through an energy harvesting power source determined according to the initial capacitor; A step of opening the energy harvesting power source and connecting a charge-sharing capacitor in parallel to the initial capacitor to sense a second voltage at the current time; A step of setting the initial capacitor to the increased capacitance of the next time step; A step of sensing a third voltage at the next time from an energy harvesting power source that has been changed according to the operating frequency changed according to the increased initial capacitor; and A step of determining whether to increase or decrease the increased initial capacitor by comparing the second voltage and the third voltage. A method including
In Paragraph 11, The step of applying the first voltage is, A step comprising short-circuiting a first switch between an energy harvesting power source determined according to the initial capacitor and the initial capacitor to apply a first voltage at the current time. method.
In Paragraph 11, The step of sensing the second voltage above is, A step of opening a first switch between the energy harvesting power source determined according to the initial capacitor and the initial capacitor; A step of short-circuiting a second switch between the initial capacitor and the charge-sharing capacitor; and A step comprising sensing a second voltage at the current time of the initial capacitor or the charge-sharing capacitor. method.
In Paragraph 11, The step of setting the increased capacitance at the above next time is, A step comprising increasing the initial capacitor of the next time step according to the increase decision of the previous time step. method.
In Paragraph 11, The step of determining whether to increase or decrease as described above is, If the above third voltage is greater than the above second voltage, it is determined to increase the above increased initial capacitor, and If the third voltage is smaller than the second voltage, it is determined to reduce the increased initial capacitor. method.
In a method for estimating maximum power in a maximum power tracking device, Step of setting the initial capacitor to the capacitance of the current time; A step of sensing a third voltage from an energy harvesting power source determined according to the initial capacitor; A step of setting the initial capacitor to the reduced capacitance of the next time step; A step of applying a first voltage to the initial capacitor through an energy harvesting power source changed according to the operating frequency changed according to the reduced initial capacitor; The step of opening the energy harvesting power source and connecting a charge-sharing capacitor in parallel to the initial capacitor to sense a second voltage at the next time point; and A step of determining whether to increase or decrease the reduced initial capacitor by comparing the second voltage and the third voltage. A method including
In Paragraph 16, The step of setting the reduced capacitance at the above next time is, A step comprising reducing the initial capacitor of the next time step according to the reduction decision of the previous time step. method.
In Paragraph 16, The step of applying the first voltage is, A step comprising short-circuiting a first switch between the energy harvesting power source changed according to the reduced initial capacitor and the reduced initial capacitor to apply the first voltage at the next time point. method.
In Paragraph 16, The step of sensing the second voltage above is, A step of opening a first switch between the energy harvesting power source changed according to the reduced initial capacitor and the reduced initial capacitor; A step of short-circuiting a second switch between the reduced initial capacitor and the charge-sharing capacitor; and A step comprising sensing a second voltage at the next time of the reduced initial capacitor or the charge-sharing capacitor. method.
In Paragraph 16, The step of determining whether to increase or decrease as described above is, If the third voltage is greater than the second voltage, it is determined to reduce the reduced initial capacitor, and If the third voltage is smaller than the second voltage, it is determined to increase the reduced initial capacitor. method.

Description

Apparatus and Method for Tracking Maximum Power This relates to a maximum power tracking technology, specifically a technique that compares power at two points in time using a switched capacitor. In many cases, it is necessary to determine whether the power changes in real time at a specific node of an electronic circuit system. Among the methods for tracking the power of an electronic circuit system, the method of tracking the maximum power is referred to as Maximum Power Point Tracking (MPPT). The maximum power point can be reached by repeating the process of comparing the power delivered at two specific points in time and adjusting the internal impedance. For example, the Perturb and Observe (P&O) algorithm finds the maximum power point by comparing the power delivered at two specific points in time. The power at a specific node can be measured by introducing a resistive component. Power can be calculated by measuring the current and voltage passing through the resistor and then multiplying the measured values. By comparing the power at two specific points in time calculated in this manner and controlling the electronic circuit in the direction that increases the power, the maximum power point can be reached. However, this method results in power loss due to the resistive component. The maximum power point can be reached by utilizing the inverse relationship between capacitor charging time and power. This can be achieved by introducing a capacitor at a specific node to maintain constant high and low voltages across it, measuring the charging time, and converting the measured time into a digital signal for analysis. Time-Domain Quantization is an example of this method. However, this approach increases circuit complexity because it requires additional components for determining the start and completion of charging, as well as for digital signal conversion. To determine increases or decreases in power, it must be measured, and measuring power requires the multiplication of voltage (V) and current (I). There are two difficulties in performing this. The first is measuring current. While the voltage component can be directly sensed and stored through a capacitor, the current component is tricky to measure. If an independent current sensor is used for current measurement, a significant amount of power is consumed, and the complexity of the system increases. The second problem that arises when tracking increases and decreases in power is multiplication. An Analog-to-Digital Converter (ADC) performs the multiplication of current and voltage in the digital domain, but power loss occurs due to the ADC, and resolution may be reduced during the process of converting analog voltage to digital. FIG. 1 is a diagram illustrating the configuration of a maximum power tracking device according to one embodiment. Figure 2 is a flowchart illustrating the operation of the maximum power tracking method as the capacitor increases. Figure 3 is a flowchart illustrating the operation of the maximum power tracking method while decreasing the capacitor. Figure 4 is an example of a maximum power tracking method that includes all scenarios of increasing and decreasing capacitors. Figure 5 is a graph showing the power graph and voltage-current characteristic graph that change as n increases. Hereinafter, embodiments are described in detail with reference to the attached drawings. However, various modifications may be made to the embodiments, and thus the scope of the patent application is not limited or restricted by these embodiments. It should be understood that all modifications, equivalents, and substitutions to the embodiments are included within the scope of the rights. The terms used in the embodiments are for illustrative purposes only and should not be interpreted as intended to be limiting. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprising" or "having" are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof. Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the embodiments pertain. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application. In addition, when describing with reference to the attached drawings, identical components are assigned the same reference numeral regardless of drawing symbols, and redundant descriptions th