阅读说明：本技术 多输入源能量提取系统及其电源转换装置与方法 (Multi-input source energy extraction system and power conversion device and method thereof ) 是由 刘国基 何昌祐 于 2018-12-28 设计创作，主要内容包括：一种多输入源能量提取系统及其电源转换装置与方法。该多输入源能量提取系统,包括一电源转换装置,其中第一与第二能量提取器分别提取第一与第二能量与而分别提供第一与第二输入电源；电源转换装置包括：可调阻抗匹配电路,根据第一输入电源产生一调整后电源；电源转换电路,转换总线电源而产生输出电源；其中能量提取系统根据调整后电源及/或第二输入电源而控制第一开关电路与第二开关电路,以选择导通调整后电源或第二输入电源其中之一而产生总线电源；且调整可调阻抗匹配电路的阻抗值,以最大化调整后电源的电压。(A multi-input source energy extraction system and a power conversion device and method thereof are provided. The multi-input source energy extraction system comprises a power supply conversion device, wherein a first energy extractor and a second energy extractor respectively extract first energy and second energy and respectively provide a first input power supply and a second input power supply; the power conversion device includes: the adjustable impedance matching circuit generates an adjusted power supply according to the first input power supply; the power supply conversion circuit is used for converting the bus power supply to generate an output power supply; the energy extraction system controls the first switch circuit and the second switch circuit according to the adjusted power supply and/or the second input power supply so as to selectively conduct one of the adjusted power supply or the second input power supply to generate a bus power supply; and the impedance value of the adjustable impedance matching circuit is adjusted to maximize the voltage of the adjusted power supply.)

1. A power conversion device, wherein a first energy extractor extracts a first energy to provide a first input power, and a second energy extractor extracts a second energy to provide a second input power; the power conversion device includes:

an adjustable impedance matching circuit, generating an adjusted power supply at a first node according to the first input power supply;

a first switch circuit coupled between the first node and a bus node;

a second switch circuit coupled between the second input power source and the bus node;

a switching control circuit for controlling the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply to selectively turn on one of the adjusted power supply or the second input power supply to generate a bus power supply at the bus node, and the switching control circuit generates an impedance control signal for adjusting an impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power supply; and

a power conversion circuit for converting the bus power to generate an output power.

2. The power conversion device of claim 1, wherein the conversion control circuit generates the bus power according to one of the following:

(1) comparing the voltage of the adjusted power supply with the voltage of the second input power supply to select the highest voltage of the adjusted power supply and the second input power supply as the bus power supply; or

(2) And comparing the voltage of the second input power supply with a first preset voltage, and selecting to conduct the second input power supply as the bus power supply when the voltage of the second input power supply is higher than the first preset voltage.

3. The power conversion device of claim 1, wherein the conversion control circuit generates a conversion control signal according to a first sensing signal to control the power conversion circuit such that the first input power or the second input power is controlled substantially at a corresponding maximum power point; wherein the first sensing signal is related to at least one of:

(1) the voltage of the regulated power supply;

(2) a voltage of the second input power supply; or

(3) The voltage of the bus supply.

4. The power conversion device of claim 3, wherein the conversion control signal controls the output power of the power conversion circuit such that the first sensing signal is not lower than a second predetermined voltage, wherein the second predetermined voltage is related to a corresponding maximum power point of the first input power or a corresponding maximum power point of the second input power.

5. The power conversion device of claim 4, wherein the conversion control circuit comprises:

a sampling maintaining circuit for sampling and maintaining the divided voltage of the open-circuit voltage of the adjusted power supply as the second preset voltage when the adjusted power supply is selected as the bus power supply; or when the second input power supply is selected as the bus power supply, sampling and maintaining the divided voltage of the open-circuit voltage of the second input power supply to be used as the second preset voltage.

6. The power conversion device of claim 1, wherein the first input power has an alternating current form; the power conversion device also comprises a rectifying circuit, wherein the rectifying circuit comprises at least one rectifying element, and the rectifying circuit is set to be one of the following components:

(1) the rectifying element is coupled between an output end of the adjustable impedance matching circuit and the first node and is used for rectifying an output signal of the adjustable impedance matching circuit and generating the adjusted power supply at the first node; or

(2) The rectifying element is coupled between the first node and the bus node and is used for rectifying the regulated power supply and generating the bus power supply at the bus node; the first switch circuit comprises the rectifier element, and the rectifier element is also used for controlling whether the regulated power supply is conducted or not to serve as the bus power supply.

7. The power conversion device of claim 6, wherein the rectifying element is a rectifying diode.

8. The power conversion device of claim 1, wherein the adjustable impedance matching circuit comprises a variable capacitor for analog and continuous adjustment of a capacitance value of the variable capacitor according to the impedance control signal, thereby analog and continuous adjustment of the impedance value of the adjustable impedance matching circuit.

9. The power conversion apparatus as claimed in claim 2, wherein the second switch circuit comprises a path switch for controlling a conduction path of the second input power and the bus power, the conversion control circuit comprises a first comparison circuit for comparing a voltage of the second input power with the first predetermined voltage to generate a first comparison result, and the conversion control circuit controls whether the path switch conducts the second input power as the bus power according to the first comparison result.

10. The power conversion device of claim 9, wherein the conversion control circuit further determines whether to enable the impedance control signal according to the first comparison result, wherein the conversion control circuit enables the impedance control signal when the voltage of the second input power is lower than the first predetermined voltage.

11. The power conversion device of claim 3, wherein the conversion control circuit comprises:

a bias sensing circuit coupled between the bus node and a sensing node for generating a second sensing signal at the sensing node according to the voltage of the bus power supply;

a clamping circuit coupled to the sensing node for clamping the second sensing signal such that the second sensing signal is not greater than a clamping voltage; and

the second comparison circuit is used for generating the conversion control signal according to the difference value of the second sensing signal and a third preset voltage.

12. The power conversion device of claim 11, wherein the bias voltage sensing circuit comprises:

a bias resistor for providing a bias current; and

a sensing capacitor coupled between the bus power supply and the sensing node in parallel with the bias resistor.

13. The power conversion device of claim 12, wherein the bias resistor is a parasitic resistor of the sensing capacitor.

14. The power conversion device of claim 11, wherein the clamping circuit comprises a clamping diode, wherein the clamping voltage is related to a forward conduction voltage of the clamping diode.

15. The power conversion device of claim 11, wherein the conversion control circuit further generates the impedance control signal according to the conversion control signal.

16. The power conversion apparatus according to claim 2, wherein the conversion control circuit selects to turn on the regulated power supply or the second input power supply as the bus power supply periodically according to a comparison result between the voltage of the regulated power supply and the voltage of the second input power supply, or periodically according to a comparison result between the voltage of the second input power supply and the first predetermined voltage.

17. The power conversion device of claim 11, wherein the power conversion circuit is configured to be one of:

(1) a boost switching power conversion circuit;

(2) a step-down switching power conversion circuit;

(3) a voltage-boosting switching type power conversion circuit;

(4) a linear power conversion circuit; or

(5) A charging circuit.

18. The power conversion device as claimed in claim 1, wherein the second input power is further coupled to the adjustable impedance matching circuit for controlling the impedance value of the adjustable impedance matching circuit to increase the voltage of the adjusted power.

19. A multiple-input source energy extraction system, comprising:

the power conversion apparatus according to any one of claims 1 to 18;

the first energy extractor; and

the second energy extractor.

20. A method for controlling a multi-input source energy extraction system, wherein the multi-input source energy extraction system comprises a power conversion device, a first energy extractor and a second energy extractor, wherein the first energy extractor extracts a first energy to provide a first input power source, and the second energy extractor extracts a second energy to provide a second input power source; the power conversion apparatus includes: an adjustable impedance matching circuit, generating an adjusted power supply at a first node according to the first input power supply; a first switch circuit coupled between the first node and a bus node; a second switch circuit coupled between the second input power source and the bus node; and a power conversion circuit for converting a bus power on the bus node to generate an output power; the method comprises the following steps:

controlling the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply to selectively conduct one of the adjusted power supply and the second input power supply to generate the bus power supply at the bus node; and

adjusting an impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power supply.

21. The method of claim 20, wherein generating the bus power comprises one of:

(1) comparing the voltage of the adjusted power supply with the voltage of the second input power supply to select the highest voltage of the adjusted power supply and the second input power supply as the bus power supply; or

(2) And comparing the voltage of the second input power supply with a first preset voltage, and selecting to conduct the second input power supply as the bus power supply when the voltage of the second input power supply is higher than the first preset voltage.

22. The method of claim 20, further comprising:

controlling the power conversion circuit according to a first sensing signal, so that the first input power supply or the second input power supply is controlled at a corresponding maximum power point; wherein the first sensing signal is related to at least one of:

(1) the voltage of the regulated power supply;

(2) a voltage of the second input power supply; or

(3) The voltage of the bus supply.

23. The method of claim 22, wherein the step of controlling the power conversion circuit comprises:

controlling the output power of the power conversion circuit so that the first sensing signal is not lower than a second preset voltage, wherein the second preset voltage is related to the corresponding maximum power point of the first input power source or the maximum power point of the second input power source.

24. The method of claim 20, wherein the second input power is further used to control the impedance value of the adjustable impedance matching circuit to increase the voltage of the adjusted power.

25. A power conversion device, wherein a first energy extractor extracts a first energy to provide a first input power, and a second energy extractor extracts a second energy to provide a second input power; the power conversion device includes:

an adjustable impedance matching circuit for generating an adjusted power at a first node according to the first input power, wherein the second input power controls an impedance value of the adjustable impedance matching circuit to maximize a voltage of the adjusted power;

a power conversion circuit for generating an output power according to the adjusted power; and

and the conversion control circuit is used for generating a conversion control signal to control the power conversion circuit, so that the adjusted power supply is controlled to be approximately at the corresponding maximum power point.

26. The power conversion device of claim 25, wherein the first energy extractor is an rf antenna or an electromagnetic induction device, the first energy is rf energy, and the first input power is ac; and the second energy extractor is a light energy cell for extracting light energy.

27. The power conversion device of claim 25, further comprising:

a first switch circuit coupled between the first node and a bus node;

a second switch circuit coupled between the second input power source and the bus node;

the conversion control circuit controls the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply so as to select and conduct one of the adjusted power supply and the second input power supply and generate a bus power supply at the bus node; the power conversion circuit converts the bus power to generate the output power.

28. The power conversion device of claim 27, wherein the conversion control circuit further generates an impedance control signal for adjusting the impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power source.

Technical Field

The present invention relates to a power conversion system, and more particularly, to a power conversion system with multiple input sources. The invention also relates to a power conversion device and a method used in the power conversion system.

Background

The prior art related to this application is: U.S. patent application No. US 20180069405A1 and "An Effective Multi-Source Energy Harvester for Low Power Applications,2011, IEEE".

In fig. 1, the U.S. patent application No. US 20180069405a1 discloses a power conversion system with multiple input sources (power conversion system 1 with multiple input sources), where the power conversion system 1 includes multiple dc-dc boost converters for respectively converting multiple input power sources provided by different energy extractors (such as the solar panel energy extractor, the piezoelectric panel energy extractor, the wind energy extractor, the magnetic induction energy extractor, the wireless rf energy extractor, etc.) and then selecting one of the power conversion paths through an input selection switch to provide an output power source to a subsequent load (such as a battery pack).

The prior art shown in fig. 1 has a disadvantage in that it is provided with a plurality of dc-dc boost converters corresponding to a plurality of energy extractors, respectively, so that the circuit size of the power conversion system 1 is large and the cost is high. In addition, the prior art cannot track the maximum power point, so the power conversion efficiency is not good.

In fig. 2, IEEE article "An Effective Multi-Source Energy Harvester for Low Power Applications,2011, IEEE" discloses a Power conversion system (Power conversion system 2 with multiple input sources) with multiple input sources in the prior art, where the Power conversion system 2 is provided with respective maximum Power point tracking circuits corresponding to the multiple input sources, and respective diodes corresponding to the multiple input sources to select the highest voltage of the different input sources, and converts the selected input Source VSC into An output Source VOUT through a dc-dc converter.

The prior art shown in fig. 2 has the disadvantage that the circuit size of the power conversion system 2 is large and the cost is high due to the arrangement of the maximum power point tracking circuits respectively corresponding to the prior art. In addition, the selection of the input source by the diode can select only the highest voltage of the input power supply.

Compared with the prior art shown in fig. 1 and 2, the present invention can share a maximum power point tracking circuit and a dc-dc conversion circuit for a plurality of input sources, thereby reducing the circuit size and the cost, and increasing the voltage of the input power source through the impedance matching circuit capable of adjusting the impedance.

Disclosure of Invention

In one aspect, the present invention provides a power conversion apparatus, wherein a first energy extractor extracts a first energy to provide a first input power, and a second energy extractor extracts a second energy to provide a second input power; the power conversion device includes: an adjustable impedance matching circuit, generating an adjusted power supply at a first node according to the first input power supply; a first switch circuit coupled between the first node and a bus node; a second switch circuit coupled between the second input power source and the bus node; a switching control circuit for controlling the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply to selectively turn on one of the adjusted power supply or the second input power supply to generate a bus power supply at the bus node, and the switching control circuit generates an impedance control signal for adjusting an impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power supply; and a power conversion circuit for converting the bus power to generate an output power.

In a preferred embodiment, the conversion control circuit generates the bus power according to one of the following: (1) comparing the voltage of the adjusted power supply with the voltage of the second input power supply to select the highest voltage of the adjusted power supply and the second input power supply as the bus power supply; or (2) comparing the voltage of the second input power supply with a first preset voltage, and selecting to conduct the second input power supply as the bus power supply when the voltage of the second input power supply is higher than the first preset voltage.

In a preferred embodiment, the conversion control circuit generates a conversion control signal according to a first sensing signal to control the power conversion circuit, so that the first input power or the second input power is controlled to be substantially at a corresponding maximum power point; wherein the first sensing signal is related to at least one of: (1) the voltage of the regulated power supply; (2) a voltage of the second input power supply; or (3) the voltage of the bus supply.

In a preferred embodiment, the conversion control signal controls the output power of the power conversion circuit such that the first sensing signal is not lower than a second predetermined voltage, wherein the second predetermined voltage is related to a corresponding maximum power point of the first input power or a maximum power point of the second input power.

In a preferred embodiment, the conversion control circuit comprises: a sampling maintaining circuit for sampling and maintaining the divided voltage of the open-circuit voltage of the adjusted power supply as the second preset voltage when the adjusted power supply is selected as the bus power supply; or when the second input power supply is selected as the bus power supply, sampling and maintaining the divided voltage of the open-circuit voltage of the second input power supply to be used as the second preset voltage.

In a preferred embodiment, the first input power source has an alternating current form; the power conversion device also comprises a rectifying circuit, wherein the rectifying circuit comprises at least one rectifying element, and the rectifying circuit is set to be one of the following components: (1) the rectifying element is coupled between an output end of the adjustable impedance matching circuit and the first node and is used for rectifying an output signal of the adjustable impedance matching circuit and generating the adjusted power supply at the first node; or (2) the rectifying element is coupled between the first node and the bus node and is used for rectifying the regulated power supply to generate the bus power supply at the bus node; the first switch circuit comprises the rectifier element, and the rectifier element is also used for controlling whether the regulated power supply is conducted or not to serve as the bus power supply.

In a preferred embodiment, the rectifying element is a rectifying diode.

In a preferred embodiment, the tunable impedance matching circuit includes a variable capacitor for analog and continuous adjustment of a capacitance of the variable capacitor according to the impedance control signal, thereby analog and continuous adjustment of the impedance value of the tunable impedance matching circuit.

In a preferred embodiment, the second switch circuit includes a path switch for controlling a conduction path between the second input power and the bus power, the conversion control circuit includes a first comparison circuit for comparing a voltage of the second input power with the first predetermined voltage to generate a first comparison result, and the conversion control circuit controls whether the path switch conducts the second input power as the bus power according to the first comparison result.

In a preferred embodiment, the switching control circuit further determines whether to enable the impedance control signal according to the first comparison result, wherein when the voltage of the second input power is lower than the first predetermined voltage, the switching control circuit enables the impedance control signal.

In a preferred embodiment, the conversion control circuit comprises: a bias sensing circuit coupled between the bus node and a sensing node for generating a second sensing signal at the sensing node according to the voltage of the bus power supply; a clamping circuit coupled to the sensing node for clamping the second sensing signal such that the second sensing signal is not greater than a clamping voltage; and a second comparison circuit for generating the conversion control signal according to a difference between the second sensing signal and a third preset voltage.

In a preferred embodiment, the bias sensing circuit comprises: a bias resistor for providing a bias current; and a sensing capacitor coupled between the bus power supply and the sensing node in parallel with the bias resistor.

In a preferred embodiment, the bias resistor is a parasitic resistor of the sensing capacitor.

In a preferred embodiment, the clamping circuit includes a clamping diode, wherein the clamping voltage is related to a forward conduction voltage of the clamping diode.

In a preferred embodiment, the switching control circuit further generates the impedance control signal according to the switching control signal.

In a preferred embodiment, the switching control circuit selects to turn on the regulated power supply or the second input power supply as the bus power supply periodically according to a comparison result between the voltage of the regulated power supply and the voltage of the second input power supply, or periodically according to a comparison result between the voltage of the second input power supply and the first preset voltage.

In a preferred embodiment, the power conversion circuit is configured as one of: (1) a boost switching power conversion circuit; (2) a step-down switching power conversion circuit; (3) a voltage-boosting switching type power conversion circuit; (4) a linear power conversion circuit; or (5) a charging circuit.

In a preferred embodiment, the second input power is further coupled to the adjustable impedance matching circuit for controlling the impedance value of the adjustable impedance matching circuit to increase the voltage of the adjusted power.

From another perspective, the present invention also provides a multi-input source energy extraction system, comprising: a power conversion apparatus as described in any of the above embodiments; the first energy extractor; and the second energy extractor.

In another aspect, the present invention also provides a method for controlling a multi-input source energy extraction system, wherein the multi-input source energy extraction system comprises a power conversion device, a first energy extractor and a second energy extractor, wherein the first energy extractor extracts a first energy to provide a first input power, and the second energy extractor extracts a second energy to provide a second input power; the power conversion apparatus includes: an adjustable impedance matching circuit, generating an adjusted power supply at a first node according to the first input power supply; a first switch circuit coupled between the first node and a bus node; a second switch circuit coupled between the second input power source and the bus node; and a power conversion circuit for converting a bus power on the bus node to generate an output power; the method comprises the following steps: controlling the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply to selectively conduct one of the adjusted power supply and the second input power supply to generate the bus power supply at the bus node; and adjusting an impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power supply.

In a preferred embodiment, the step of generating the bus power comprises one of: (1) comparing the voltage of the adjusted power supply with the voltage of the second input power supply to select the highest voltage of the adjusted power supply and the second input power supply as the bus power supply; or (2) comparing the voltage of the second input power supply with a first preset voltage, and selecting to conduct the second input power supply as the bus power supply when the voltage of the second input power supply is higher than the first preset voltage.

In a preferred embodiment, the method further comprises: controlling the power conversion circuit according to a first sensing signal, so that the first input power supply or the second input power supply is controlled at a corresponding maximum power point; wherein the first sensing signal is related to at least one of: (1) the voltage of the regulated power supply; (2) a voltage of the second input power supply; or (3) the voltage of the bus supply.

In a preferred embodiment, the step of controlling the power conversion circuit comprises: controlling the output power of the power conversion circuit so that the first sensing signal is not lower than a second preset voltage, wherein the second preset voltage is related to the corresponding maximum power point of the first input power source or the maximum power point of the second input power source.

In a preferred embodiment, the second input power is further used for controlling the impedance value of the adjustable impedance matching circuit to increase the voltage of the adjusted power.

From another perspective, the present invention also provides a power conversion apparatus, wherein a first energy extractor extracts a first energy to provide a first input power, and a second energy extractor extracts a second energy to provide a second input power; the power conversion device includes: an adjustable impedance matching circuit for generating an adjusted power at a first node according to the first input power, wherein the second input power controls an impedance value of the adjustable impedance matching circuit to maximize a voltage of the adjusted power; a power conversion circuit for generating an output power according to the adjusted power; and a conversion control circuit for generating a conversion control signal to control the power conversion circuit so that the adjusted power supply is controlled at the corresponding maximum power point.

In a preferred embodiment, the first energy extractor is an rf antenna or an electromagnetic induction device, the first energy is rf energy, and the first input power is ac; and the second energy extractor is a light energy cell for extracting light energy.

In a preferred embodiment, the power conversion apparatus further comprises: a first switch circuit coupled between the first node and a bus node; a second switch circuit coupled between the second input power source and the bus node; the conversion control circuit controls the first switch circuit and the second switch circuit according to the voltage of the adjusted power supply and/or the voltage of the second input power supply so as to select and conduct one of the adjusted power supply and the second input power supply and generate a bus power supply at the bus node; the power conversion circuit converts the bus power to generate the output power.

In a preferred embodiment, the conversion control circuit further generates an impedance control signal for adjusting the impedance value of the adjustable impedance matching circuit to maximize the voltage of the adjusted power supply.

The purpose, technical content, features and effects of the invention will be more easily understood through the following detailed description of specific embodiments.

Drawings

FIG. 1 shows a block diagram of a prior art multiple input source energy extraction system.

FIG. 2 shows a block diagram of a prior art multiple input source energy extraction system.

Fig. 3A is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to an embodiment of the invention.

Fig. 3B shows a characteristic diagram corresponding to fig. 3A.

Fig. 3C shows a characteristic graph of the energy extractor.

Fig. 3D is a schematic diagram of a power conversion device according to an embodiment of the invention.

Fig. 4 is a schematic diagram of an embodiment of an adjustable impedance matching circuit in the power conversion apparatus according to the present invention.

Fig. 5A is a schematic diagram of a power conversion device according to an embodiment of the invention.

FIGS. 5B-5C are schematic diagrams illustrating an embodiment of a conversion control circuit in the power conversion apparatus according to the present invention.

FIG. 6A is a schematic diagram of an embodiment of a rectifier circuit in the power conversion apparatus according to the invention.

FIG. 6B is a schematic diagram of an embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention.

FIG. 7 is a schematic diagram of an embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention.

FIG. 8 is a schematic diagram of an embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention.

FIG. 9 is a schematic diagram of an embodiment of a conversion control circuit in the power conversion apparatus according to the present invention.

FIG. 10 is a schematic diagram of an embodiment of a bias voltage sensing circuit in the power conversion device according to the present invention.

FIG. 11 is a schematic diagram of an embodiment of a conversion control circuit in the power conversion apparatus according to the present invention.

Fig. 12 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to another embodiment of the invention.

Fig. 13 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to another embodiment of the invention.

Fig. 14 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to still another embodiment of the invention.

Fig. 15 is a schematic diagram of another embodiment of an adjustable impedance matching circuit in the power conversion apparatus according to the present invention.

Fig. 16 is a schematic diagram of another embodiment of an adjustable impedance matching circuit in the power conversion apparatus according to the present invention.

Description of the symbols in the drawings

10, 10' adjustable impedance matching circuit

100, 100' power conversion device

20 first switching circuit

200,300 energy extractor

3A multi-input source energy extraction system

30 second switching circuit

40 power supply conversion circuit

50, 50' conversion control circuit

53,56 comparison circuit

54 bias sensing circuit

55 clamping circuit

58 impedance control circuit

60, 60' rectifier circuit

80 switch circuit

Fr resonance frequency

N1 first node

NB bus node

PMAX maximum power point

VA regulated power supply

VB impedance control signal

VBUS bus power supply

VCTL conversion control signal

VI1 first input power supply

VI2 second input power supply

VMP maximum power voltage

VOC open circuit voltage

VR1 preset voltage

Second preset voltage of VR1, VR2 and VR3

Detailed Description

The drawings in the present disclosure are schematic and are intended to show the coupling relationship between circuits and the relationship between signal waveforms, and the circuits, signal waveforms and frequencies are not drawn to scale.

Referring to fig. 3A, fig. 3A is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to an embodiment of the invention (the multi-input source energy extraction system 3A and the power conversion device 100). The multi-input source energy extraction system 3A includes a plurality of energy extractors 200 and 300, and a power conversion device 100.

The energy extractors 200 and 300 may be respectively configured to extract the corresponding first energy and the corresponding second energy to be respectively converted into the first input power VI1 and the second input power VI 2. In one embodiment, the energy extractor 200 may extract the energy in the form of ac and convert the extracted energy into the first input power VI1 in the form of ac, for example, the energy extractor 200 may be a piezoelectric energy extractor for extracting the energy converted into the vibration pressure and converting the energy into the first input power VI1 in the form of ac, and for example, the energy extractor 200 may be a radio frequency antenna or an electromagnetic induction device for extracting the energy converted into the radio frequency energy or electromagnetic energy and converting the energy into the first input power VI1 in the form of ac. In an embodiment, the energy extractor 300 may extract energy in a form of direct current and convert the energy into the second input power VI2 in a form of direct current, for example, the energy extractor 300 may be a photovoltaic cell or a thermoelectric element for extracting light energy or heat energy and converting the light energy or heat energy into the second input power VI2 in a form of direct current. Of course, the multiple energy extractors of the multiple-input source energy extraction system may be any combination of the various forms of energy extractors described above.

Referring to fig. 3A, the power conversion apparatus 100 includes an adjustable impedance matching circuit 10, a first switch circuit 20, a second switch circuit 30, a conversion control circuit 50, and a power conversion circuit 40.

The adjustable impedance matching circuit 10 is used for generating an adjusted power supply VA at a first node N1 according to a first input power supply VI 1. The first switch circuit 20 is coupled between the first node N1 and the bus node NB for controlling a conduction path between the first node N1 and the bus node NB. The second switch circuit 30 is coupled between the second input power source VI2 and the bus node NB for controlling a conduction path between the second input power source VI2 and the bus node NB.

The switching control circuit 50 is used for controlling the first switch circuit 20 and the second switch circuit 30 according to the voltage of the regulated power supply VA and/or the voltage of the second input power supply VI2 to selectively turn on one of the regulated power supply VA or the second input power supply VI2 to generate the bus power supply VBUS at the bus node NB. According to the present invention, the switching control circuit 50 can select the regulated power supply VA or the second input power supply VI2 as the bus power supply VBUS in a variety of different ways. In one embodiment, the conversion control circuit 50 compares the voltage of the regulated power supply VA with the voltage of the second input power supply VI2 to select the highest one of the regulated power supply VA and the second input power supply VI2 as the bus power supply VBUS. In another embodiment, the conversion control circuit 50 compares the voltage of the second input power VI2 with a first predetermined voltage, and selects to turn on the second input power VI2 as the bus power VBUS when the voltage of the second input power VI2 is higher than the first predetermined voltage.

Further, according to the present invention, alternatively, the conversion control circuit 50 may select to turn on the regulated power supply VA or the second input power supply VI2 as the bus power supply VBUS periodically according to the comparison result of the voltage of the regulated power supply VA and the voltage of the second input power supply VI2, or periodically according to the comparison result of the voltage of the second input power supply VI2 and the first preset voltage VR 1.

The power conversion circuit 40 is used for converting the bus power VBUS to generate the output power VO. The power conversion circuit 40 may be configured as, for example, but not limited to, a boost-type switching power conversion circuit, a buck-type switching power conversion circuit, a boost-type switching power conversion circuit, a linear power conversion circuit, or a charging circuit. It should be noted that the charging circuit is a power conversion circuit capable of performing at least a constant current power conversion mode and a constant voltage power conversion mode, and is used for performing corresponding power conversion modes at different charging stages of the rechargeable battery. The details of the power conversion circuit are not described herein, and are understood by those skilled in the art based on the teachings of the present invention.

In addition, according to the present invention, in an embodiment, the switching control circuit 50 is further configured to generate the impedance control signal VB for adjusting the impedance value of the adjustable impedance matching circuit 10, so as to control or adjust the characteristic parameter of the adjusted power supply VA. Referring to fig. 3B, fig. 3B shows a characteristic diagram corresponding to fig. 3A, as shown in the figure, in an embodiment where the first energy is, for example, rf energy and the energy extractor 200 is an rf antenna, adjusting the impedance value of the adjustable impedance matching circuit 10 can change the resonant frequency of the energy extractor 200, for example, to make it correspond to the resonant frequency Fr in fig. 3B, so that the energy extractor 200 can extract the maximum energy, and in an embodiment, the voltage of the adjusted power supply VA can be controlled by adjusting the impedance value of the adjustable impedance matching circuit 10, and in an embodiment, the transformation control circuit 50 adjusts the impedance value of the adjustable impedance matching circuit 10 by the impedance control signal VB to maximize the voltage of the adjusted power supply VA.

Referring to fig. 3A, fig. 3C and fig. 3D, fig. 3C shows a characteristic curve diagram of a typical energy extractor (such as a light energy extractor), and fig. 3D shows a schematic diagram of an embodiment of a power conversion device according to the present invention. As shown in fig. 3C, the maximum power point PMAX of a typical energy extractor corresponds to a voltage slightly below its open circuit voltage VOC (maximum power voltage VMP). In one embodiment, as shown in fig. 3D, the conversion control circuit 50 is further configured to generate the conversion control signal VCTL according to the first sensing signal VSEN1 to control the power conversion circuit 40 such that the first input power VI1 or the second input power VI2 is controlled at a corresponding maximum power point. In one embodiment, the conversion control signal VCTL controls the output power of the power conversion circuit 40 such that the first input power VI1 or the second input power VI2 is controlled at a corresponding maximum power point. It should be noted that the input power VI in fig. 3D corresponds to the regulated power VA or the second input power VI2 in the previous embodiment, and the switch circuit 80 is the corresponding first switch circuit 20 or the second switch circuit 30, the same applies below.

The first sensing signal VSEN1 can be implemented in various embodiments, and in particular, according to the present invention, the first sensing signal VSEN1 is related to at least one of: (1) adjusting the voltage of the rear power supply VA; (2) the voltage of the second input power VI 2; or (3) the voltage of the bus power supply VBUS. More specifically, when the switching control circuit 50 selects to turn on the regulated power supply VA to generate the bus power VBUS at the bus node NB, the switching control circuit 50 generates the switching control signal VCTL according to the voltage of the regulated power supply VA or the voltage of the bus power VBUS to control the power conversion circuit 40 such that the first input power supply VI1 is substantially controlled at its maximum power point. When the transition control circuit 50 selects to turn on the second input power VI2 to generate the bus power VBUS at the bus node NB, the transition control circuit 50 generates the transition control signal VCTL according to the voltage VVI2 of the second input power VI2 or the voltage of the bus power VBUS to control the power conversion circuit 40 such that the second input power VI2 is controlled at its maximum power point.

It should be noted that: although the first or second input power source is controlled at its corresponding maximum power point because the parasitic effect of the circuit components itself or the matching between the components is not necessarily ideal, in practice, the first or second input power source may not be precisely controlled at its corresponding maximum power point, but only close to the maximum power point, that is, according to the present invention, it is acceptable that there is a certain degree of error from the maximum power point due to the non-ideality of the circuit, that is, the above-mentioned "approximately" is controlled at its maximum power point, and the other references in this specification also refer to "approximately" as well.

The tunable impedance matching circuit 10 may include basic impedance matching components, such as inductors and capacitors, wherein the impedance value of the tunable impedance matching circuit 10, and thus the impedance value (input or output impedance) of the multi-input source energy extraction system and the power conversion device, may be adjusted by setting the impedance matching components to be tunable. Referring to fig. 4, fig. 4 is a schematic diagram illustrating an embodiment of an adjustable impedance matching circuit in a power conversion apparatus according to the present invention. As shown in the figure, in the present embodiment, the tunable impedance matching circuit 10 includes a variable capacitor 11 for analog and continuous adjustment of the capacitance of the variable capacitor 11 according to the impedance control signal VB, thereby analog and continuous adjustment of the impedance value of the tunable impedance matching circuit 10. In this particular embodiment, the adjustable impedance matching circuit 10 further includes an inductor L1 and a capacitor C12. In one embodiment, the variable capacitor 11 may be a voltage-controlled variable capacitor or a voltage-controlled variable capacitance diode D11, for example. In one embodiment, the switching control circuit 50 may correspondingly include an impedance control circuit 58 for generating the impedance control signal VB.

It should be noted that, in other embodiments, the variable capacitor 11 may also be a combination of a capacitor and a switch, in which case, the impedance control signal VB controls the switch to adjust the capacitance value of the variable capacitor 11.

In one embodiment, the conversion control signal VCTL controls the output power of the power conversion circuit 40 such that the first sensing signal VSEN1 is not lower than a second predetermined voltage, wherein the second predetermined voltage is related to a maximum power point of the corresponding first input power VI1 or a maximum power point of the corresponding second input power VI 2. Referring to fig. 5A, fig. 5A shows a schematic diagram of a power conversion apparatus according to an embodiment of the invention, as shown in fig. 5A, in an embodiment, the conversion control circuit 50 may include a comparison circuit 51 for comparing the first sensing signal VSEN1 with the second predetermined voltage VR2 to generate the conversion control signal VCTL to control the output power of the power conversion circuit 40 such that the first sensing signal VSEN1 is not lower than the second predetermined voltage VR 2.

Specifically, when the switching control circuit 50 selects to turn on the regulated power supply VA to generate the bus power supply VBUS at the bus node NB, the second predetermined voltage VR2 is related to the maximum power point of the first input power supply VI1 (or corresponding to the regulated power supply VA). On the other hand, when the conversion control circuit 50 selects to turn on the second input power VI2 to generate the bus power VBUS at the bus node NB, the second predetermined voltage VR2 is related to the maximum power point of the second input power VI 2. Referring back to fig. 3C, the second predetermined voltage VR2 may be, for example, the maximum power voltage VMP or a voltage similar thereto. It should be noted that the positive and negative terminals in the comparison circuit are relative concepts, which are merely exemplary and not limiting.

FIGS. 5B-5C are schematic diagrams illustrating an embodiment of a conversion control circuit in the power conversion apparatus according to the present invention. As shown in fig. 5B, in an embodiment, the conversion control circuit 50 includes a sample-and-hold circuit 52 for sampling and maintaining the divided voltage of the open-circuit voltage of the regulated power supply VA as the second predetermined voltage VR2 when the regulated power supply VA is selected as the bus power supply VBUS; alternatively, when the second input power VI2 is selected as the bus power VBUS, the divided voltage of the open-circuit voltage of the second input power VI2 is sampled and maintained as the second predetermined voltage VR 2. The open-circuit voltage may correspond to the VOC shown in fig. 3C, for example, and is a voltage corresponding to the regulated power supply VA, the first input power supply VI1, or the second input power supply VI2 when the current of the regulated power supply VA, the first input power supply VI1, or the second input power supply VI2 is 0. In one embodiment, the voltage division of the open circuit voltage can be achieved, for example, by R51 and R52 shown in the figure. In one embodiment, the sample-and-hold circuit 52 includes a switch S51 and a capacitor C51. Referring to fig. 5C, in an embodiment, the second switch circuit 30 (or the first switch circuit 20) may include a path switch SP for controlling the aforementioned conducting path, in a preferred embodiment, the sampling and holding time is when the corresponding first switch circuit or the second switch circuit is controlled to be turned off, in the embodiment shown in fig. 5C, that is, when the path switch SP is turned off, at the same time, the conversion control circuit 50 may sample and hold the divided voltage of the aforementioned open-circuit voltage by the switch S51 and the capacitor C51 to generate the second predetermined voltage VR 2.

FIG. 6A is a schematic diagram of an embodiment of a rectifier circuit in the power conversion apparatus according to the invention. As mentioned above, in an embodiment, the first input power VI1 may be in an ac form, in which case, the power conversion apparatus 100 may further include a rectifying circuit 60, wherein the rectifying circuit 60 includes at least one rectifying element 61. As shown in fig. 6A, in the present embodiment, the rectifying element 61 is coupled between the output terminal of the adjustable impedance matching circuit 10 and a first node N1 for rectifying the output signal PAC of the adjustable impedance matching circuit 10 to generate the regulated power supply VA at the first node N1.

FIG. 6B is a schematic diagram of an embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention. In one embodiment, the rectifier circuits may share some or all of the components of the switching circuit. For example, as shown in fig. 6B, the rectifying circuit 60 'is coupled between the first node N1 and the bus node NB, and more specifically, the rectifying element 61' is coupled between the first node N1 and the bus node NB for rectifying the regulated power supply VA to generate the bus power supply VBUS at the bus node NB; in this embodiment, the first switch circuit 20 also includes a rectifying element 61 ', and the rectifying element 61 ' is further configured to control whether to turn on the regulated power supply VA as the bus power supply VBUS, in other words, the rectifying element 61 ' may correspond to the aforementioned path switch. As shown in fig. 6A-6B, in one embodiment, rectifying element 61 (or 61') is rectifying diode D61. In other embodiments, the rectifying element may also be a rectifying switch, and the rectification is performed in a synchronous rectification manner.

FIG. 7 is a schematic diagram of a more specific embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention. In the present embodiment, the rectifying circuit 60' includes rectifying diodes D61 and D62 for rectifying the regulated power VA to generate the bus power VBUS at the bus node NB, and the first switch circuit 20 also includes a rectifying diode D61 (corresponding to the rectifying element), in the present embodiment, the rectifying diode D61 may correspond to the path switch, specifically, when the regulated power VA is higher than the bus power VBUS, the rectifying diode D61 is turned on, i.e., the first input power VI1 is turned on as the bus power VBUS, and on the other hand, when the regulated power VA is lower than the bus power VBUS, the rectifying diode D61 is turned off, i.e., the conducting path between the first input power VI1 and the bus power VBUS is turned off.

Fig. 8 is a schematic diagram of an embodiment of a rectifying circuit and a switching circuit in the power conversion apparatus according to the present invention. As shown, in an embodiment, the second switch circuit 30 includes a path switch SP for controlling a conduction path between the second input power VI2 and the bus power VBUS, in the embodiment, the conversion control circuit 50 includes a comparison circuit 53 for comparing a voltage of the second input power VI2 with a predetermined voltage VR1 (e.g., corresponding to the aforementioned first predetermined voltage) to generate a comparison result CP1, and the conversion control circuit 50 controls whether the path switch SP conducts the second input power VI2 as the bus power VBUS according to the comparison result CP 1. In one embodiment, when the voltage of the second input power VI2 is higher than the predetermined voltage VR1, the path switch SP is controlled to be turned on to selectively turn on the second input power VI2 as the bus power VBUS. In one embodiment, when the voltage of the second input power VI2 is lower than the predetermined voltage VR1, the path switch SP is controlled to turn off, i.e., turn off the second input power VI2 to turn off the conduction path of the bus power VBUS, in this case, the rectifier diode D61 of the present embodiment is turned on when the voltage of the bus power VBUS is lower than the voltage of the regulated power VA, i.e., turn on the first input power VI1 as the bus power VBUS.

Referring to fig. 8, in an embodiment, the conversion control circuit 50 further determines whether to enable the impedance control signal VB according to the first comparison result CP1, and specifically, the first comparison result CP1 may control whether the impedance control circuit 58 enables the impedance control signal VB (e.g., via the enable signal EN associated with the first comparison result CP1) to control the impedance value of the adjustable impedance matching circuit 10. Furthermore, in an embodiment, when the voltage of the second input power VI2 is lower than the predetermined voltage VR1, the second switch circuit is turned off, and the switching control circuit 50 can activate the impedance control signal VB to control the impedance value of the adjustable impedance matching circuit 10, so as to maximize the power or voltage of the first input power. On the other hand, in an embodiment, when the voltage of the second input power VI2 is higher than the predetermined voltage VR1, the switching control circuit 50 disables the impedance control signal VB.

Fig. 9 is a schematic diagram of another embodiment of a power conversion apparatus according to the present invention, in which a conversion control circuit is used to track a maximum power point. In one embodiment, the transition control circuit 50 includes a bias sensing circuit 54, a clamping circuit 55, and a second comparison circuit 56.

The bias sensing circuit 54 is coupled between the bus node NB and the sensing node NS for generating a second sensing signal VSEN2 at the sensing node NS according to the voltage of the bus power VBUS. The clamping circuit 55 is coupled to the sensing node NS for clamping the second sensing signal VSEN2 such that the second sensing signal VSEN2 is not greater than the clamping voltage. The second comparing circuit 56 is configured to generate the conversion control signal VCTL according to a difference between the second sensing signal VSEN2 and the third predetermined voltage VR3, so that the first input power VI1 or the second input power VI2 is controlled substantially at the corresponding maximum power point.

FIG. 10 is a schematic diagram of an embodiment of a bias voltage sensing circuit in the power conversion device according to the present invention. In one embodiment, the bias sensing circuit 54 includes a bias resistor R53 and a sensing capacitor C52. A bias resistor R53 for providing a bias current; the sensing capacitor C52 is coupled between the bus power supply VBUS and the sensing node NS in parallel with the bias resistor R53. In one embodiment, the bias resistor R53 is a parasitic resistor of the sensing capacitor C52, i.e., for practical circuits, only the sensing capacitor is needed in the bias sensing circuit 54.

With continued reference to fig. 10, in one embodiment, the clamping circuit 55 includes a clamping diode D51, wherein the clamping voltage is related to the forward conduction voltage of the clamping diode D51.

FIG. 11 is a schematic diagram of an embodiment of a conversion control circuit in the power conversion apparatus according to the present invention. In this embodiment, the circuit configuration of the switching control circuit 50 related to maximum power point tracking is the same as that shown in fig. 9 or fig. 10, and as shown in fig. 11, in one embodiment, the switching control circuit 50 generates the impedance control signal VB according to the switching control signal VCTL, and specifically, the impedance control circuit 58 can also generate the impedance control signal VB according to the switching control signal VCTL.

Fig. 12 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to another embodiment of the invention. In this embodiment, the multi-input source energy extraction system 12 and the power conversion apparatus 100 'are similar to the embodiment of fig. 3A, except that in the power conversion apparatus 100', the second input power source VI2 is further coupled to the adjustable impedance matching circuit 10 'for controlling the impedance value of the adjustable impedance matching circuit 10' to maximize the voltage of the adjusted power source VA. Specifically, in one embodiment, the adjustable impedance matching circuit 10 'further adjusts the impedance value of the adjustable impedance matching circuit 10' according to the voltage of the second input power VI 2.

With reference to fig. 12, the above-described configuration has a particular effect that the multi-input-source energy extraction system 12 can still be successfully powered on and output power to a subsequent circuit (e.g., a battery) when the first and second energies are in relatively poor states, for example, in the present embodiment, the first and second energies are respectively a wireless rf energy and an optical energy, and the first and second energies 200 and 300 are respectively a corresponding rf antenna and an optical energy battery, and under the condition of relatively low wireless rf energy, it may not be possible to provide enough voltage to enable the conversion control circuit 50 to generate an impedance control signal VB with an appropriate level to control the impedance value of the adjustable impedance matching circuit 10 'to maximize the voltage of the adjusted power VA, in which case, the second input power VI2 may provide an appropriate bias voltage (e.g., the voltage of the second input power VI 2) to the adjustable impedance matching circuit 10' The impedance value of the adjustable impedance matching circuit 10' is controlled to increase (preferably maximize) the voltage of the adjusted power supply VA. When the voltage of the regulated power supply VA is properly increased, the switching control circuit 50 can generate the impedance control signal VB with a proper level to control the impedance value of the adjustable impedance matching circuit 10', so as to maximize the voltage of the regulated power supply VA, thereby implementing the above-mentioned functions. In this embodiment, the voltage of the second input power VI2 may not be high enough to provide an appropriate bias voltage to the adjustable impedance matching circuit 10 'to control the impedance value of the adjustable impedance matching circuit 10' to increase the voltage of the regulated power VA. In one embodiment, the voltage of the second input power VI2 may be less than 1V, and in one embodiment, the voltage of the second input power VI2 may be less than 0.5V as the bias voltage provided to the adjustable impedance matching circuit 10'.

Fig. 13 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to another embodiment of the invention. The power conversion apparatus 100' of the present embodiment is similar to the power conversion apparatus 100 "of fig. 12, and the difference is that the adjustable impedance matching circuit 10" may not be controlled by the impedance control signal VB, and the impedance value of the adjustable impedance matching circuit 10 "is controlled by the second input power VI2, in other words, the impedance control signal VB may be omitted from the conversion control circuit 50", wherein other functions of the conversion control circuit 50 "may correspond to the conversion control circuit 50 in the other embodiments (e.g., fig. 3A).

Fig. 14 is a schematic diagram of a multi-input source energy extraction system and a power conversion device thereof according to still another embodiment of the invention. The power conversion apparatus 100 ″ of fig. 14 is similar to the power conversion apparatus 100 ″ of fig. 13, and the difference is that in the power conversion apparatus 100 ″ of fig. 14, the first switch circuit and the second switch circuit may be further omitted. Specifically, in the present embodiment, in the power conversion apparatus 100 ″, the first energy extractor extracts the first energy to provide the first input power VI1, and the second energy extractor extracts the second energy to provide the second input power, wherein the first and second energy extractors and the corresponding first and second energies can refer to the related description of fig. 3A, which is not repeated here. In this embodiment, the power conversion apparatus 100 "includes an adjustable impedance matching circuit 10", a conversion control circuit 50 ", and a power conversion circuit 40.

In the embodiments of fig. 13 and 14, similar to the embodiment of fig. 12, the second input power VI2 may be used to provide an appropriate bias voltage (e.g., the voltage of the second input power VI 2) to the adjustable impedance matching circuit 10 'to control the impedance value of the adjustable impedance matching circuit 10' so as to increase (preferably maximize) the voltage of the regulated power VA.

Referring to fig. 14, the adjustable impedance matching circuit 10 ″ generates the adjusted power supply VA at the first node N1 according to the first input power supply VI1, wherein the second input power supply VI2 controls the impedance value of the adjustable impedance matching circuit 10 ″ to maximize the voltage of the adjusted power supply VA. The power conversion circuit 40 generates an output power VO according to the regulated power VA. In one embodiment, the power conversion circuit 40 converts the regulated power VA to generate the output power VO. The switching control circuit 50 ″ is configured to generate a switching control signal VCTL to control the power conversion circuit 40 such that the regulated power VA is substantially controlled at the corresponding maximum power point. In fact, when the regulated power supply VA is controlled substantially at the corresponding maximum power point, it also means that the first input power supply VI1 is controlled substantially at the corresponding maximum power point.

Fig. 15 is a schematic diagram of another embodiment of an adjustable impedance matching circuit in the power conversion apparatus according to the present invention. The power conversion device 100 "and the adjustable impedance matching circuit 10" of fig. 15 may correspond to the embodiments of fig. 13 and 14. As shown in fig. 15, in the present embodiment, the variable capacitor 11 of the adjustable impedance matching circuit 10 ″ is configured to adjust the capacitance of the variable capacitor 11 according to the second input power VI2, thereby adjusting the impedance of the adjustable impedance matching circuit 10. In one embodiment, the variable capacitor 11 is configured to adjust the capacitance of the variable capacitor 11 according to the voltage of the second input power VI 2.

Fig. 16 is a schematic diagram of another embodiment of an adjustable impedance matching circuit in the power conversion apparatus according to the present invention. The power conversion device 100 'and the adjustable impedance matching circuit 10' of fig. 16 may correspond to the embodiment of fig. 12. As shown in fig. 16, in the present embodiment, the variable capacitor 11 of the tunable impedance matching circuit 10' can simultaneously and continuously adjust the capacitance of the variable capacitor 11 according to the impedance control signal VB and/or the second input power VI2, thereby adjusting the impedance value of the tunable impedance matching circuit 10. In one embodiment, the variable capacitor 11 is configured to adjust the capacitance of the variable capacitor 11 according to the voltage of the second input power VI 2.

The present invention has been described with respect to the preferred embodiments, but the above description is only for the purpose of making the content of the present invention easy to understand for those skilled in the art, and is not intended to limit the scope of the present invention. The embodiments described are not limited to single use, but may be used in combination, for example, two or more embodiments may be combined, and some components in one embodiment may be substituted for corresponding components in another embodiment. Further, equivalent variations and combinations are contemplated by those skilled in the art within the spirit of the present invention, and the term "processing or computing or generating an output result based on a signal" is not limited to the signal itself, and includes, if necessary, performing voltage-to-current conversion, current-to-voltage conversion, and/or scaling on the signal, and then processing or computing the converted signal to generate an output result. It is understood that equivalent variations and combinations, not necessarily all illustrated, will occur to those of skill in the art, which combinations are not necessarily intended to be limiting. Accordingly, the scope of the present invention should be determined to encompass all such equivalent variations as described above.