WO2017047480A1

WO2017047480A1 - Energy-harvesting wireless device and system

Info

Publication number: WO2017047480A1
Application number: PCT/JP2016/076365
Authority: WO
Inventors: 伸之石岡; 啓太桑原; 陽二菅間
Original assignee: 株式会社日立製作所; 東日本旅客鉄道株式会社
Priority date: 2015-09-17
Filing date: 2016-09-08
Publication date: 2017-03-23
Also published as: JP2018207551A

Abstract

Provided is a technology for controlling activation timing that enables an energy-harvesting wireless device to be activated at a predetermined activation time. The present invention has: a power generation unit that generates power by using sunlight as an energy source; a power storage unit that stores the power; a wireless unit that transmits signals wirelessly; a control device that controls the wireless unit; a storage device that stores information used by the control device; and a timer capable of measuring time. The control device has: a first means that controls a device to at least two states, that is, an active state in which the wireless unit transmits signals wirelessly, and an idle state in which less power is consumed than in the active state; a second means that acquires a start time (activation time) for the active state stored in the storage device; a third means that acquires the sunrise time; and a fourth means that controls the start timing for the idle state on the basis of the activation time and the sunrise time.

Description

Energy generation type wireless device and system

The present invention relates to power saving of an energy harvesting type wireless device, and in particular, even when the power generation unit cannot supply power to the energy harvesting type wireless device before the sunrise time, The present invention relates to a technology for starting a power generation type wireless device.

A wireless sensor network is built with wireless devices (sensor nodes) equipped with sensors to provide a system that can centrally grasp the “state” and “change” of people, things, and facilities.

Generally, wireless devices are often installed in places where it is difficult for people to enter or places where it is difficult to supply commercial power to drive the wireless devices. In addition, when the wireless device is driven by a built-in battery, periodic battery replacement work has a problem of spending time and labor of workers.

Therefore, an energy harvesting wireless device using energy harvesting (energy harvesting) technology that obtains electric power for driving the wireless device from energy such as sunlight, vibration, and heat is provided.

Generally, an energy-generating wireless device must be small and able to operate for a long time. However, the amount of power that can be generated by the power generation unit (solar panel, etc.) and the amount of power that can be charged in the power storage unit (battery, capacitor, etc.) is limited. Desired.

Generally, as a method for suppressing the power consumption of the energy-generating wireless device, control of activation timing such as putting the energy-generating wireless device to sleep is used in a time zone where communication with other wireless devices is unnecessary. Control of start-up timing here refers to the “start-up state” in which all functions of the energy-generating wireless device can be used, and the main functions of the energy-generating wireless device are suspended in order to prevent the power consumption of power supplies such as capacitors. This is to switch and control the “pause state” that is the state that has been made. For example, when in a dormant state, the energy-generating wireless device does not communicate with other wireless devices or sensors, and operates so as to be activated only when communicating.

JP 2012-80622 A

When a solar panel is used as an energy harvesting wireless device, the solar panel often cannot supply power stably to the energy harvesting wireless device for 24 hours.

Patent Document 1 discloses a method of predicting a future amount of sunshine based on the solar radiation time information acquired by a plurality of surrounding wireless devices arranged from the past, and controlling the startup timing of the wireless device, thereby reducing the power consumption of the wireless device. A series of methods for controlling the amount are described.

However, in order to predict the amount of sunlight, a plurality of wireless devices are required, and each wireless device needs to correlate with the amount of solar radiation. In reality, each wireless device is affected by surrounding structures. In order to receive, there was a problem that the correlation with the amount of solar radiation became weak.

In the field test of the energy harvesting type wireless device conducted by the inventors, it was found that the start-up state of the wireless device becomes unstable due to insufficient charge amount in the winter when the light irradiation amount decreases.

In particular, when a solar panel is used as a power supply source for an energy harvesting wireless device, if the sunrise time is later than the time at which the energy harvesting wireless device is to be activated, such as in winter, it is sufficient for the energy harvesting wireless device at startup. In some cases, power cannot be supplied. In this case, it is necessary to operate the wireless device with power charged in a power source such as a capacitor until sunrise. However, there was a problem that the charging amount was insufficient and the startup could not be sufficiently performed. It was also found that the influence of sunrise time is more dominant than the influence of weather as a factor that affects the amount of charge. That is, according to the study by the inventors, the inventors have found that there is a correlation between the sunrise time (season) and the time at which it can be activated.

An object of the present invention is to provide an energy harvesting type wireless device that can be stably activated at a desired activation time regardless of the sunrise time.

This application includes a plurality of means for solving the above problems.

One aspect of the present invention is an energy generating wireless system that transmits data acquired by a sensor as it is or after processing it wirelessly. In this system, a power generation unit that receives sunlight and generates electric power, a capacitor that accumulates electric power, a voltage monitoring unit that monitors the voltage of the capacitor, and the electric power accumulated in the capacitor transmit data wirelessly. A wireless unit, a control device, and a storage device that stores information used by the control device.

The control device includes first means for controlling the system in at least two states, an active state in which the wireless unit can transmit data wirelessly and a sleep state in which power consumption is lower than the active state. A second means for determining the sunrise time based on the output of the voltage monitoring unit and storing it in the storage device; and a third means for acquiring the start time (startup time) of the startup state stored in the storage device; And a fourth means for determining the anteroposterior relationship between the activation time and the sunrise time stored in the storage device.

Further, when the activation time is the same as or later than the sunrise time, the operation is suspended from the activation state on the condition that the voltage monitored by the voltage monitoring unit falls below the first threshold or reaches a predetermined time. There is a fifth means for switching to the state. When the activation time is earlier than the sunrise time, the voltage monitored by the voltage monitoring unit falls below a second threshold value that is greater than the first threshold value, or the voltage monitored by the voltage monitoring unit is a second value. There is a sixth means for switching from the activated state to the dormant state on condition that the time falls below the threshold value. And a seventh means for adding a value calculated based on the time interval between the activation time and the sunrise time to the first threshold value to generate a second threshold value and storing it in the storage device.

In a more specific example, the seventh means integrates the activation state voltage drop rate in the time interval between the activation time and the sunrise time, and further adds a positive value of 0 or more as a margin, The threshold value is generated.

In another specific example, the control device determines the sunset time based on the output of the voltage monitoring unit, and stores the voltage of the capacitor at the sunset time in the storage device. The storage device stores the voltage drop rate of the capacitor per unit time when the system is put into a hibernation state with the electric power stored in the capacitor as the hibernation state voltage drop rate. The seventh means further generates the second threshold value by further using the capacitor voltage and the resting state voltage drop rate at the sunset time.
In another specific example, the storage device stores the voltage drop rate of the capacitor per unit time when the system is put into a hibernation state with the electric power stored in the capacitor as the hibernation state voltage drop rate. The maximum voltage that can be stored in the capacitor is stored as the capacitor maximum voltage. The seventh means generates the second threshold value by further using the capacitor maximum voltage and the resting state voltage drop rate.

The various numerical values stored in the storage device can be preliminarily stored. In addition, the energy-generating wireless system can autonomously measure in the field, calculate as necessary, and store it in the storage device. Also, the numerical value can be updated as necessary. In this case, it is possible to control the system more in line with the operating state.

For example, the second means determines the sunrise time every day based on, for example, the voltage of the voltage monitoring unit, the fourth means determines the order of the sunrise time every day, and the seventh means the second threshold every day. Is stored in the storage device.

As an example of a specific control method, it can be performed by comparing the voltage monitored by the voltage monitoring unit with the stored threshold value. As another method, the timing at which the voltage monitored by the voltage monitoring unit crosses the threshold may be calculated and stored in advance, and control based on time may be performed.

Another aspect of the present invention provides a power generation unit that generates power using sunlight as an energy source, a power storage unit that accumulates power, a wireless unit that wirelessly transmits a signal, a control device that controls the wireless unit, and a control It is an energy harvesting type wireless device having a storage device for storing information used by the device and a timer capable of measuring time.

The control device includes: a first unit that controls the device in at least two states: a start state in which the wireless unit transmits a signal wirelessly; and a sleep state that consumes less power than the start state; and a start stored in the storage device A second means for acquiring the start time (start-up time) of the state, a third means for acquiring the sunrise time, and a fourth means for controlling the start timing of the dormant state based on the start-up time and the sunrise time And having.

In an example of a more specific aspect, a voltage monitoring unit that monitors the voltage of the power storage unit is provided. The fourth means is a means for determining the anteroposterior relationship between the activation time and the sunrise time, and when the activation time is earlier than the sunrise time, the power required for maintaining the activation state from the activation time to the sunrise time. A means for calculating the amount, a means for calculating the voltage of the power storage unit (resting voltage) as a condition for starting the hibernation state based on the required amount of power, and the voltage monitoring unit causes the voltage of the power storage unit to fall below the resting voltage. And a means for starting a dormant state at a timing when it is determined that it has become.

In another example of a more specific embodiment, the third means determines the sunrise time based on the power generation state of the power generation unit, and stores the determined sunrise time every day in the storage device. The fourth means performs processing using the latest sunrise time stored in the storage device.

In another example of the more specific embodiment, the fourth means uses a starting voltage lower than the pause voltage when the starting time is later than the sunrise time, and the voltage of the power storage unit is set to the starting voltage by the voltage monitoring unit. Means for starting a dormant state at a timing determined to be as follows.

In another example of a more specific embodiment, the power storage unit is a capacitor. In addition, the storage device stores the starting voltage drop rate of the capacitor in the starting state before the sunrise time, and the fourth means is necessary by calculation using the starting voltage drop rate, the starting time, and the sunrise time. A power amount is calculated, and a value obtained by adding at least a voltage corresponding to the required power amount to the start-up voltage is calculated as a pause voltage.

Another aspect of the present invention relates to a power generation unit that obtains power for driving a wireless device from solar energy, a power storage unit for storing power generated by the power generation unit, and an amount of power stored in the power storage unit. A voltage monitoring unit that measures and outputs voltage information; a timer that outputs time information; a wireless unit that communicates with other wireless devices; a memory that records sunrise time and activation time; a power generation unit; a power storage unit; The wireless device includes a voltage monitoring unit, a timer, a wireless unit, and a control device that controls the memory. In this device, the control device includes means for calculating a sunrise time and recording it in a memory, and a power generation unit, a power storage unit, a voltage monitoring unit, a timer, a radio unit, a memory, and a control device from the start time to the sunrise time. Means for calculating the amount of power consumed in the activated state. The voltage monitoring unit, the timer, the radio unit, the memory, and a unit for calculating the amount of power consumed in the sleep state that suppresses the power consumption of the power storage unit by stopping some functions of the control device. In addition, when only the energy stored in the power storage unit is set to the start-up state, the unit for measuring the voltage drop rate of the power storage unit per unit time and the case where the sleep state is set only by the energy stored in the power storage unit And means for measuring a voltage drop rate of the power storage unit per unit time.

According to this aspect, it is possible to calculate the amount of power to be stored in the power storage unit in advance from the sunrise time and the start time, and to reliably start the energy generating wireless device at a predetermined start time. In particular, the energy harvesting type wireless device calculates the sunrise time by itself, and further calculates the amount of power to be stored in the power storage unit in advance from the startup time from the sunrise time and a predetermined startup time.

Another aspect of the present invention includes a power generation unit that generates power using sunlight as an energy source, a power storage unit that accumulates power, a wireless unit that wirelessly transmits a signal, a control device that controls the wireless unit, and a control In the energy harvesting type wireless device having a storage device for storing information used in the device and a timer capable of measuring time, the control device controls the method.

The control device includes: a first process for controlling the device in at least two states: an active state in which the wireless unit transmits a signal wirelessly; and a sleep state in which power consumption is lower than the active state; A second process for acquiring the start time (start time) of the activation state, a third process for acquiring the sunrise time, and a fourth process for controlling the start timing of the hibernation state based on the activation time and the sunrise time And processing.

Another aspect of the present invention includes a power generation unit that generates power using sunlight as an energy source, a power storage unit that accumulates power, a wireless unit that wirelessly transmits a signal, a control device that controls the wireless unit, and a control A program for controlling a control device in an energy harvesting type wireless device having a storage device for storing information used in the device and a timer capable of measuring time.

The program controls the device in at least two states: a start state in which the wireless unit sends signals wirelessly to a control device hardware composed of a microcomputer, and a sleep state that consumes less power than the start state. A first process for acquiring, a second process for acquiring a start time (start time) of the start state stored in the storage device, a third process for acquiring a sunrise time, and a start time and a sunrise time. Based on this, control is performed so as to execute a fourth process for controlling the start timing of the hibernation state.

It is possible to start the energy harvesting type wireless device reliably at the starting time.

FIG. 2 is a block diagram illustrating an example of a system configuration diagram of the energy-generating wireless device 1. The graph figure which shows an example of the voltage change of the electrical storage part 12 in the summer (time when sunrise time is earlier than starting time). The graph which shows an example of the voltage change of the electrical storage part 12 in winter (time when sunrise time is later than starting time). The graph figure which shows an example of the voltage change of the electrical storage part 12 when the energy harvesting type | mold radio | wireless apparatus 1 is made to rest to a rest voltage in winter (time when sunrise time is later than starting time). The flowchart figure which showed the operation example of the energy generation type radio | wireless apparatus 1. FIG. The graph figure which shows an example of the voltage change of the electrical storage part 12 which considered the voltage drop of a dormant state in winter (time when sunrise time is later than starting time). Explanatory drawing which shows the example of embodiment of a present Example. FIG. 3 is a block diagram showing an example of another system configuration diagram of the energy-generating wireless device 1.

Embodiments will be described in detail with reference to the drawings. However, the present invention is not construed as being limited to the description of the embodiments below. Those skilled in the art will readily understand that the specific configuration can be changed without departing from the spirit or the spirit of the present invention.

In the structure of the invention described below, the same portions or portions having similar functions are denoted by the same reference numerals in different drawings, and redundant description may be omitted.

In this specification and the like, notations such as “first”, “second”, and “third” are attached to identify the constituent elements, and do not necessarily limit the number or order. In addition, a number for identifying a component is used for each context, and a number used in one context does not necessarily indicate the same configuration in another context. Further, it does not preclude that a component identified by a certain number also functions as a component identified by another number.

The position, size, shape, range, etc. of each component shown in the drawings and the like may not represent the actual position, size, shape, range, etc. in order to facilitate understanding of the invention. For this reason, the present invention is not necessarily limited to the position, size, shape, range, and the like disclosed in the drawings and the like.

Hereinafter, with reference to FIG. 1 to FIG. 5, the details of the control method and program of the start timing of the energy harvesting type wireless device 1 in the first embodiment will be described.

In addition, in Example 1, although the electric power generation part 11 is demonstrated as a solar panel, if it can carry out environmental power generation, it will not be limited to a solar panel. For example, in addition to photoelectric conversion of sunlight, there is one that converts thermal energy from sunlight into electric power. Similarly, in the first embodiment, the power storage unit is described as a capacitor. However, the capacitor is not limited to the capacitor as long as the energy generated by the power generation unit 11 can be stored.

<Characteristics of capacitor>
As shown in Equation 1, the amount of power stored in the capacitor is proportional to the voltage. Therefore, calculating the amount of power stored in the power storage unit 12 by the voltage monitoring unit 13 is equivalent to obtaining the voltage of the power storage unit 12.

<Formula 1>
Q = C x V
Q: Electric energy stored in the capacitor C: Electric capacity (fixed value)
V: Voltage.

<Start-up time _{T 1>}
The energy-generating wireless device 1 according to the first embodiment operates from the early morning activation time T _s (becomes “activated state”), but activates at night time (time zone from sunset T ₂ to sunrise T ₁ ). However, it does not have to be activated. Since the power generation unit 11 cannot supply power 20 to the power storage unit 12 in the nighttime, the energy harvesting type wireless device 1 is operated with the power stored in the power storage unit 12. The energy harvesting type wireless device 1 stops (forced) when the voltage of the power storage unit 12 falls below the starting voltage V1 (minimum voltage of the power storage unit 12 for the energy harvesting type wireless device 1 to operate normally). Will be "hibernated").

<Nighttime>
The night at this time is a time zone from sunset to sunrise, and is a time zone during which the power generation unit 11 cannot supply power 20 to the power storage unit 12.

<Description of Figure 1>
FIG. 1 is an example of a system configuration diagram of the energy-generating wireless device 1. Hereinafter, each function of the energy-generating wireless device 1 will be described with reference to FIG.

<Energy generation type wireless device 1>
The energy harvesting type wireless device 1 activates the energy harvesting type wireless device 1 with solar energy, for example, and does not require power supply by a battery or a cable. As shown in FIG. 1, the energy harvesting type wireless device 1 includes a power generation unit 11, a power storage unit 12, a voltage monitoring unit 13, a control device 14, a timer 15, a wireless unit 16, and a storage device (memory) 19. Hereinafter, each function of the energy-generating wireless device 1 will be described.

<Power generation part 11>
The power generation unit 11 obtains electric power by collecting energy such as sunlight, illumination light, vibration generated by a machine, heat, and the like. For example, a solar cell panel can be used. The energy generated by the power generation unit 11 is supplied 20 to the power storage unit 12.

<Power storage unit 12>
The power storage unit 12 stores power generated by the power generation unit 11, and is, for example, a capacitor or a chargeable / dischargeable battery. When a solar panel is used as the power generation unit 11, the power generation unit 11 cannot supply power 20 to the power storage unit 12 from sunset to sunrise. In this case, the energy harvesting type wireless device 1 is activated using the energy stored in the power storage unit 12.

<Voltage monitoring unit 13>
The voltage monitoring unit 13 has a function of calculating the amount of power stored in the power storage unit 12 and provides the voltage information 18 to the control device 14. As described above, when a capacitor is used for the power storage unit, the amount of stored power is proportional to the voltage, and thus the voltage may be obtained as the amount of power.

<Voltage information 18>
The voltage information 18 is information describing the amount of electric power (voltage) stored in the power storage unit 12.

<Timer 15>
The timer 15 has a function of providing time information 17 to the control device 14. It is assumed that the time information 17 of the timer 15 is not cleared even when it falls below the starting voltage V1.

<Storage device (memory) 19>
The memory 19 stores information recorded in advance and information recorded by the control device 14. Information previously recorded is the starting voltage V1, the voltage drop rate is a start time T _s and the like. Further, information recorded by the control unit 14 is a sunrise time T ₁ and the rest voltage V2 and the voltage information 18 and the like. As the memory 19, a nonvolatile semiconductor memory or a small magnetic disk device can be used. It is assumed that the information recorded in the memory 19 is not cleared (volatilized) even when it falls below the starting voltage V1.

<Starting voltage V1>
The starting voltage is a minimum voltage of the power storage unit 12 for the energy harvesting type wireless device 1 to operate normally. The starting voltage V1 is recorded in the memory 19 in advance.

<Voltage drop rate>
In the winter season (time when the sunrise time is later than the start time), the power generation unit 11 cannot supply power 20 to the power storage unit 12 from the start time to the sunrise time, so only the energy stored in the power storage unit 12 can be used. It is necessary to activate the energy harvesting wireless device 1. At that time, the voltage drop rate of the power storage unit per unit time is defined as the voltage drop rate.

<Calculation method of voltage drop rate>
The voltage drop rate may be recorded in the memory 19 in advance, but may be calculated by the control device 14 by the following method. That is, for example, in the winter season (time when the sunrise time is later than the activation time), the control device 14 obtains the voltage drop rate per unit time from the activation time to the sunrise time by the voltage monitoring unit 13.

<Radio unit 16>
The wireless unit has a function of exchanging transmissions with other wireless devices 2. For example, when the energy-generating wireless device 1 transmits data from a sensor attached thereto to the other wireless device 2, at least a transmission function is provided. In addition, a reception function for receiving instructions and data from the outside may be provided.

<Control device 14>
The control device 14 has a function of controlling the voltage monitoring unit 13, the timer 15, the wireless unit 16, and the memory 19 for acquiring power and acquiring voltage information 18 from the voltage monitoring unit 13. Further, a function of inputting and processing measurement data from various sensors (not shown) may be provided.

The control device 14 is composed of, for example, a microcomputer and includes an input device, an output device, a processing device, a storage device, and the like. For example, it is a one-chip integrated circuit device (LSI), and control and calculation operations described later can be executed by software control.

Note that the memory 19 may be built in the integrated circuit device as a semiconductor memory. Further, all or a part of the functions of the voltage monitoring unit 13 and the timer 15 can be realized by controlling the control device 14 configured by a microcomputer with software.

<Energy Harvest>
Although it is desirable that the energy-generating wireless device 1 is small and can operate for a long time, the amount of power that can be generated by the power generation unit 11 and the amount of power that can be charged in the power storage unit 12 are limited, and the energy-generating wireless device 1 is as much as possible. Low power consumption is required.

<Control of startup timing>
Therefore, the control device 14 controls the activation timing of each function, so that it is possible to suppress the power consumption of the power storage unit 12 during a time period when communication with the other wireless device 2 is not performed. The activation timing control mentioned here is to repeat the “activation state” in which all functions of the energy-generating wireless device 1 can be used and the “sleep state” in which only the minimum necessary functions are operated. .

<Hibernate>
The hibernation state is a state in which the power consumed by the power storage unit 12 is suppressed by causing the control device 14 to suspend the functions of the voltage monitoring unit 13 and the radio unit 16, for example. In a typical example, in the sleep state, the energy generating wireless device 1 is stopped or restricted from communicating with the other wireless device 2.

<Startup state>
The activated state refers to a state in which all functions of the power generation unit 11, the power storage unit 12, the voltage monitoring unit 13, the control device 14, the timer 15, the wireless unit 16, and the memory 19 are activated. Note that more complicated control can be performed by providing an intermediate state between the hibernation state and the activation state in multiple stages. In the intermediate state, for example, only a part of the functions of the power generation unit 11, the power storage unit 12, the voltage monitoring unit 13, the control device 14, the timer 15, the radio unit 16, and the memory 19 are activated.

<Explanation of Figure 2>
FIG. 2 is an example of a voltage change of the power storage unit 12 in summer. Graph 27 shows the change in voltage of power storage unit 12. The summer referred to here, sunrise time T ₁ is the season of the early state from start-up time T _S. In summer, since the sunrise time T ₁ is early morning than the activation time T _S, as the voltage of power storage unit 12 falls below the starting voltage V1 at nighttime (time zone after sunset T ₂ until sunrise T _1), starting power supply 20 is performed from the power generation unit 11 to the power storage unit 12 before the time _{T S.} Thus, the activation time T _S has started the voltage V1 or voltage, it is possible to operate the energy harvesting wireless device 1.

<Start time T _S >
The activation time T _S in Figure 2, energy harvesting wireless device 1 is recorded at the time a and advance in the memory 19 to start.

<Sunrise time _{T 1>}
The sunrise time T ₁ of the 2 is defined as the time that enables the power supply 20 to the power storage unit 12 from the power generation unit 11. As the device itself, it can be determined autonomously by whether or not the power generation unit can substantially generate power. Alternatively, meteorological sunrise time information may be input from the outside and substituted. The same applies to the sunset time.

<Sunset time _{T 2>}
The sunset time T ₂ of the FIG. 2, is defined as a time when the power supply 20 becomes impossible to power storage unit 12 from the power generation unit 11. As shown in FIG. 2, since the power supply 20 is performed in the power storage unit 12 from the power generation unit 11 to the sunset time T _2, the voltage 27 of the power storage unit 12 continues to rise. In this embodiment, for simplicity, if the sunrise time T ₁ at sunset time T _2, the power generation amount of the power generation unit 11 is made larger than the consumption of energy harvesting wireless device 1.

After sunset time T _2, since the power generation portion 11 can not be powered 20 to the power storage unit 12, to reflect the power consumed by the active state, the voltage of the power storage unit decreases with a constant gradient. Then, the hibernation mode when it becomes less than the starting voltage V1 (T ₃ in FIG. _2).

<Supplement to Figure 2>
Thus, earlier than sunrise T ₁ is the start time T _S, as the voltage 27 of the power storage unit 12 falls below the starting voltage V1 at nighttime, the power to the power storage unit 12 from the power generation unit 11 before the start time 21 Supply 20 takes place. Therefore, there is a voltage equal to or higher than the startup voltage V1 at the startup time 21, and the energy harvesting type wireless device 1 can be operated.

<Explanation of Figure 3>
FIG. 3 is an example of a voltage change of the power storage unit 12 in winter. Here in winter and is, sunrise time T ₁ is a season of slow state than the start-up time T _s. In Figure 3, also in the nighttime (time zone after sunset T ₂ until sunrise T _1), the voltage 27 of the power storage unit 12 exceeds the activation voltage V1.

However, even it is started well above the starting voltage V1 at the time of activation time T _s, after activation until sunrise T _1, can not supply power, lower than the starting voltage V1 by the power consumption, normally in the middle May not be able to maintain the correct startup state.

<Description of FIG. 4>
FIG. 4 shows an example for stably starting the energy harvesting wireless device 1 at the start time T _s even in winter in view of the phenomenon of FIG. In the example of FIG. 4, an example is shown in which the amount of power consumed by the energy-generating wireless device 1 is calculated in advance from the start time T _s to the sunrise time T ₁ and stored in the power storage unit 12.

Specifically, after sunset T _2, rather than energy harvesting wireless device 1 activates to below the starting voltage V1, the transition from the startup state at rest voltage V2 dormant.

<Pause voltage V2>
The quiescent voltage V2 can be expressed by Equation 2.

<Formula 2>
Resting voltage V2 = starting voltage V1 + (voltage drop rate) * (starting time T _s −sunrise time T ₁ ).

As seen in FIG. 4, after sunset T ₂ , the state transitions to the resting state at time T ₄ when the voltage 27 reaches the resting voltage V ₂ . This control, after starting, even if there is a voltage drop due to the power consumption of up to sunrise T _1, sunrise until time T ₁ it becomes possible to maintain the activation voltage V1. For the sake of safety, a value obtained by adding a margin to the sleep power V2 obtained by Expression 2 may be used as the sleep power. In that case, the margin α is added to the right side of Equation 2. α is a positive value greater than or equal to 0, and may be, for example, a few percent of the value of (startup voltage V1 + (voltage drop rate) * (startup time T _s −sunrise time T ₁ )).

<Description of FIG. 5>
FIG. 5 is a flowchart showing a series of operation examples of the energy-generating wireless device 1 for realizing the control of FIG. Hereinafter, a series of operations of the energy-generating wireless device 1 will be described with reference to FIG. As described above, such control can be performed by control by the control device 14.

<S51>
The voltage of the power storage unit 12 is equal to or higher than the activation voltage V1, and the energy harvesting type wireless device 1 is activated. As a specific example, it may be the time when the power generation unit 11 starts power generation at the sunrise time, or may be an arbitrary designated time near noon where power is available. The specified time may be stored in the memory 19.

<S52>
The control device 14 acquires the sunrise time T ₁ and the activation time T _s recorded in the memory 19. Then, by comparing the sunrise time T ₁ and the start-up time T _s, judges Which one is the early morning.

Here, the memory 19 may store a daily activation time and a daily sunrise time in advance. Alternatively, the data may be transmitted from the other wireless device 2 collectively or as data every day via the wireless unit 16 and stored in the memory 19.

The sunrise time, as described in the following <method of calculating the sunrise time T _1>, the most recent data of the power generation start time of the power generation unit 11, may be stored in the memory as a day before the sunrise time, this, It may be used as the sunrise time of the day. At this time, if the information of the timer 15 is used together, the accuracy can be improved. In the method of using the data of the power generation start time, the energy harvesting type wireless device 1 can autonomously collect the data, and thus has an advantage of being maintenance-free. Further, when the power generation unit is an optical panel, it is possible to reflect the irradiation condition of sunlight on the panel.

Controller 14, if the direction of activation time T _s from the sunrise time T ₁ is determined to early morning, so the power generation portion 11 at the activation time T _s can power 20 to the power storage unit 12, the processing of FIG. 5 is ended To do.

That is, in the nighttime (time zone after sunset T ₂ until sunrise T _1), as the voltage of power storage unit 12 falls below the starting voltage V1, since the direction of sunrise T ₁ than the activation time T _s is early morning, starting at time T _s can be expected to have reached the start-up voltage V1. In addition, the energy harvesting type wireless device 1 can operate by receiving power supply from the power generation unit 11 after being activated at the activation time T _s . Therefore, as shown in FIG. 2, the start voltage V1 may be used to control switching between the start state and the sleep state.

<S53>
Controller 14, if the direction of sunrise T ₁ than the activation time T _s is determined to early morning, and calculates the time from the start time T _s until sunrise time T _1.

<S54>
If direction of sunrise T ₁ than the activation time T _s is the early morning, in order to activate the energy harvesting wireless device 1 to start time T _s is energy harvesting from the start time T _s to the storage unit 12 until sunrise T ₁ It is necessary to store electric power for operating the wireless device 1.

The control device 14 calculates the pause voltage V2 from <Expression 2>. The control device 14 calculates the pause voltage V2 and then stores it in the memory 19.
<Formula 2>
Resting voltage V2 = starting voltage V1 + (voltage drop rate) * (starting time T _s −sunrise time T ₁ ).

<S55>
The control device 14 acquires voltage information 18 from the voltage monitoring unit 13. Further, the pause voltage V <b> 2 is acquired from the memory 19.

<S56>
The control device 14 compares the voltage information 18 with the pause voltage V2. The acquisition and comparison of the voltage information 18 are performed at predetermined time intervals, for example, once every minute. Here, when the voltage information 18 is lower than the pause voltage V2, the process proceeds to (S58).

<S58>
The control device 14 transitions to a dormant state by pausing each function of the voltage monitoring unit 13, the memory 19, and the radio unit 16.

<S59>
The control device 14 acquires the time information 17 from the timer 15 and the activation time T _s from the memory 19. Here, when the time information 17 is the same time as _the start time T _s or past this time _{, the process} proceeds to (S60).

<S60>
By operating each function of the voltage monitoring unit 13, the memory 19, the timer 15, and the wireless unit 16, the state is shifted to the activated state.

<Method of calculating the sunrise time T _1>
Controller 14, a time when the power generation portion 11 starts the power supply 20 to the power storage unit 12 is acquired by the timer 15 is recorded in the memory 19 the time as sunrise time T _1.

<Other wireless device 2>
The other wireless device 2 is a base station that collects data wirelessly transmitted from, for example, the energy-generating wireless device 1. It is not limited to the energy harvesting type, and power supply by a battery, a cable or the like may be used.

<Supplement>
2, 3, and 4 are simplified for explaining the first embodiment. For example, the voltage of the power storage unit 12 does not necessarily become the maximum at the sunset time 23.

The form of Example 1 should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

In the above embodiment, the power storage unit 12 is assumed to be a capacitor. In the case of a capacitor, as described in <Equation 2> and FIG. 4, since the voltage drop rate is linear, the pause voltage V2 can be calculated by a simple calculation. When, for example, a storage battery other than the capacitor is used for the power storage unit 11, the voltage drop rate may be nonlinear. In this case, data of a voltage drop corresponding to the time from the start time T _s to the sunrise time T ₁ in FIG. 4 may be stored in the memory 19 as a table in advance by simulation or experiment.

However, the capacitor is inexpensive, and in the case of a capacitor, it is only necessary to provide the control device 14 with a simple calculation function. Therefore, the combination of the capacitor and the control method of FIG. There are benefits.

<Overview of Example 2>
In the first embodiment, for simplification, only the activation state (the state in which all the functions of the voltage monitoring unit 13, the control device 14, the timer 15, the wireless unit 16, and the memory 19 are activated) is stored in the power storage unit 12. It is assumed that the voltage drop of the power storage unit 12 does not occur in the resting state (the state where the control device 14 pauses the functions of the voltage monitoring unit 13 and the wireless unit 16).

Actually, a very small current continues to flow even in the resting state, and the power storage unit 12 itself is also spontaneously discharged, so that the voltage drops little by little even in the resting state.

As a result, for example, in winter, when the voltage of the power storage unit 12 falls below the starting voltage V1 at nighttime, because the voltage of the power storage unit 12 even if the activation time T _s is less than the starting voltage V1, sunrise time T _The energy harvesting type wireless device 1 cannot be activated until it becomes ₁ .

Therefore, in the second embodiment, the details of the control method and program of the start timing of the energy harvesting type wireless device 1 when the voltage drop in the dormant state is taken into account will be described.

<Voltage drop rate in startup state>
6, night-time (time period after sunset T ₂ until sunrise T _1), and the ratio of the voltage drop of the power storage unit 12 per unit time in the activated state, is defined as the voltage drop rate of the activated state.

<Rate voltage drop rate>
6, night-time (time period after sunset T ₂ until sunrise T _1), and the ratio of the voltage drop of the power storage unit 12 per unit in the hibernation time, that the voltage drop rate of the hibernation. Here, it is defined as a voltage drop due to natural discharge of the power storage unit 12.

<Switching voltage V3>
In FIG. 6, the voltage that transitions from the activated state to the inactive state is defined as a switching voltage V3.

<Switching time _{T 4>}
6, defines the time of transition to the dormant state from the active state and change time T _4.

<Explanation of FIG. 6>
Graph 27 in FIG. 6, in the winter (sunrise T ₁ is the time later than the activation time T _s), illustrates an example of a voltage change in the power storage unit 12 in consideration of the voltage drop dormant. Sunset time T _2, and later, since the power generation unit 11 is no longer able to power 20 to the power storage unit 12, the voltage of power storage unit 12 is gradually drops sharply. The rate of voltage drop per unit time is the voltage drop rate in the activated state. On the other hand, after the switching time T ₄ (the time when the start state is changed to the hibernation state), since the hibernation state is entered, the voltage of the power storage unit 12 gradually decreases. Thus, the rate of voltage drop of power storage unit 12 in the resting state per unit time is referred to as the resting state voltage drop rate.

<Switching voltage V3>
By calculating the optimum value of the switching voltage V3, it is possible to reliably start the energy harvesting type wireless device 1 at the start time T _s even in winter (when the sunrise time is later than the start time). Hereinafter, the switching voltage V3 is calculated.

<Calculation of switching voltage V3>
Here, the switching voltage V3 can be calculated from

Equations

3 and 4.

<Formula 3>
Switching voltage V3 = startup voltage V1
+ (Voltage drop rate in rest state) * (Switching time T ₄ -Starting time T _s )
+ (Voltage drop rate in startup state) * (Startup time T _s -Sunrise time T ₁ )
<Formula 4>
Switching time T ₄ = (Voltage at sunset time T ₂₋ Switching voltage V 3) / (Voltage drop rate in starting state)

<Data acquisition method>
The starting voltage V1, the starting time Ts _, the voltage drop rate in the hibernation state, and the voltage drop rate in the start state are stored in the memory 19 in advance.

Sunrise time _{T 1,} sunset time _{T 2,} is obtained as follows. Controller 14, a time when the power generation portion 11 starts the power supply 20 to the power storage unit 12 is acquired by the timer 15 is recorded in the memory 19 the time as sunrise time T _1. Further, the control unit 14, the time at which the power generation unit 11 stops power supply 20 to the power storage unit 12 is acquired by the timer 15 is recorded in the memory 19 the time as sunset time T _2.

Voltage sunset time T _2, obtains the voltage at the sunset time T _2, the time of the voltage monitoring unit 13 and stored in the memory 19 by the controller 14.

<Supplement>
As explained above, after sunset time T _2, the control unit 14 by transitioning the dormant state from the active state when the voltage of the power storage unit 12 falls below the switching voltage V3, environmentally reliably start time T _s The power generation type wireless device 1 can be activated.

<Supplement>
FIG. 6 is simplified for explaining the second embodiment. For example, not necessarily the voltage of power storage unit 12 to the sunset time T _2, is maximized. Further, the voltage drop rate of the power storage unit 12 from the sunset time T _2, to change time T _{4 (time} of transition from the activated state to a rest state) and the voltage drop rate of sunrise T ₁ from the start time T _s is the same However, it is just for convenience and may be different.

<Sunrise time _{T 1>}
In Example 1, Example 2, as a method for obtaining the sunrise time T _1, the control unit 14, a time when the power generation portion 11 starts the power supply 20 to the power storage unit 12 is acquired by the timer 15, sunrise the time The time T ₁ was recorded in the memory 19. Throughout the year, but it may be a method allowed to prerecorded sunrise time T ₁ in the memory 19.

<Sunset time _{T 2>}
In Example 2, as a method for obtaining the sunset time T _2, the control unit 14, the time at which the power generation unit 11 stops power supply 20 to the power storage unit 12 is acquired by the timer 15, and the time and sunset time 23 memory 19 recorded. Throughout the year, but it may be a way to keep to record in advance the sunset time T _2, the memory 19.

In the control method of the first embodiment, the method of performing control using the pause voltage V2 has been described. However, as is clear from FIG. 4, it can be the V2, the voltage value of the sunset time T _2, also determine the switching time T ₄ when the voltage drop rate of the active state is known. Therefore, without voltage monitoring, the switching time T ₄ obtained is stored in the memory 19 may be controlled by time.

In the control method of the second embodiment, the method of performing control using the pause voltage V3 has been described. However, as apparent from FIG. 6, it can also be obtained with V3, and the voltage value of the sunset time T _2, the change time T ₄ when the voltage drop rate of the active state is known. Therefore, without voltage monitoring, the switching time T ₄ obtained is stored in the memory 19 may be controlled by time.

Although not shown in FIGS. 2, 3, 4, and 6, when a capacitor is used for the power storage unit on the assumption that the power generated by the power generation unit 11 exceeds the power consumption, there are the following merits. That is, the capacitor has an upper limit of the capacity, the sunset time T _2, it is assumed that the power storage to full capacity. Thus, the maximum voltage value assuming VM, VM can be obtained pause voltage V3 or change time T ₄ from the voltage drop rate of the V2 and activated state since it is known. According to this method, it is not necessary to measure the voltage value at sunset time T2 as in the _second and fourth embodiments, and in the

equations

3 and 4, a VM may be used instead. Therefore, as in Example 4, it may be stored resting voltage V3 or change time T ₄ obtained in the memory 19, which may control, based on the.

Also, by this finding based, by adjusting the capacitance and switching time T _4, it is possible to use the smallest possible capacitor in the required range, it is possible to reduce the cost of the apparatus. In particular, since the amount of power to be stored in the power storage unit in advance can be calculated from the sunrise time and the start time, it is possible to provide the energy harvesting type wireless device 1 using a capacitor having the minimum necessary electric capacity. Therefore, since the capacitor size can be reduced as compared with the conventional method, the space can be saved and the energy-saving wireless device can be reduced in size and weight.

FIG. 7 shows an example of an embodiment which is an application example of the present invention. The example of FIG. 7 is an example in which the energy harvesting type wireless device 1 described in the first to fifth embodiments is used for maintenance of the transmission line (electric wire) 70. For example, when the conductive member deteriorates or overcurrent occurs, the temperature of the transmission line 70 increases due to heat generation. Such an abnormality is detected by the temperature sensor 71, and the detected data is processed by the control device 14 of the energy harvesting wireless device 1, stored in the memory 15, and transmitted from the wireless unit 16 to the other wireless device 2 in the activated state. The

In the application example as shown in FIG. 7, it is expensive to manually maintain the energy-generating wireless device 1 itself. Therefore, it is desirable that the energy-generating wireless device 1 operates as autonomously as possible. In FIG. 7, only one pair of the energy-generating wireless device 1 and the sensor 71 is shown, but in reality, a large number of devices are arranged in a very large number of places.

The data transmitted to the other wireless device 2 is accumulated in the data accumulation center 73 via a wired or wireless path 72. The data accumulated in the center 73 can be monitored and used by the management terminal 75 via the local communication network 74 or the like.

FIG. 8 is a specific example of the energy harvesting type radio apparatus 1 shown in FIG. The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted.

The configuration unique to FIG. 8 will be described. In the example of FIG. 8, the sensor 71 is built in the energy-generating wireless device 1, but may be externally attached. The power generation unit 11 uses a solar panel, and the power storage unit 12 uses a capacitor. The control device 14 is a one-chip microcomputer and includes an input / output unit 801 and a processing unit 802. In addition, the control device 14 may incorporate a memory. A nonvolatile semiconductor memory was used for the storage unit 19. The semiconductor memory stores a startup time 803, a sunrise time 804, a sunset time voltage or capacitor capacity 805, a startup state voltage drop rate 806, a dormant state voltage drop rate 807, sensor data 808, and the like. The processing unit 802 performs overall control of the energy-generating wireless device 1, processing of sensor data 808, and various calculations using data in the storage unit 19. Control of the entire apparatus includes switching control between an active state and a hibernation state.

Starting time 803, sunrise time 804, sunset voltage or capacitor capacity 805, starting state voltage drop rate 806, resting state voltage drop rate 807, etc. may be stored in advance. However, in order to reflect the actual situation in the usage environment, there is an advantage in the method in which the energy-generating wireless device 1 autonomously acquires data.

When the sunrise time 804 and the sunset voltage 805 are acquired based on the output of the voltage monitoring unit 13, it is possible to reflect the irradiation condition of sunlight on the power generation unit (solar panel) 11. As described above, the startup state voltage drop rate 806 is a voltage drop rate of the capacitor per unit time when the system is started up with the power stored in the capacitor. The hibernating voltage drop rate 807 is a voltage drop rate of the capacitor per unit time when the system is put into hibernation with the electric power stored in the capacitor. The startup state voltage drop rate 806 and the dormant state voltage drop rate 807 may be stored in advance because a linear drop rate is assumed when a capacitor is used for the power storage unit 12. If a value is periodically acquired based on the above, it is possible to cope with a change in characteristics over time. One or a plurality of activation times 803 may be stored in advance according to conditions. If the wireless unit 16 can receive the activation time 803, the activation time is obtained from the received data and stored in the storage device 19. May be.

Sensor data 808 is data acquired by the sensor 71, and is transmitted collectively or sequentially from the wireless unit 16 in the activated state.

<Supplement>
Any component expressed in the singular herein shall include the plural unless the context clearly dictates otherwise.

In the above embodiment, the control device 14 may be configured by a single computer, or any part of the input device, output device, processing device, and storage device may be configured by another computer. . In the embodiment, it is assumed that the functions of the invention are realized by controlling the hardware of the control device 14 by software stored in the recording device 19. However, in this embodiment, functions equivalent to those configured by software can be realized by hardware such as FPGA (Field Programmable Gate Array) and ASIC (Application Specific Integrated Circuit). Such an embodiment is also included in the scope of the examples.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace the configurations of other embodiments with respect to a part of the configurations of the embodiments.

It can be used for wireless sensor networks, etc., by wireless devices (sensor nodes) equipped with sensors.

1: Energy generation type wireless device 2: Other wireless device 11: Power generation unit 12: Power storage unit 13: Voltage monitoring unit 14: Control device 15: Timer 16: Radio unit T ₁ : Sunrise time 19: Memory 20: Power supply T _s : Startup time T ₂ : Sunset time T ₃ : Battery dead time V1: Startup voltage V2: Pause voltage 27: Change in voltage of power storage unit T ₄ : Switching time (time of transition from the startup state to the pause state)
V3: Switching voltage (voltage that transitions from the start state to the sleep state)
S51: Start S52: Comparison of sunrise time 22 and activation time 21 S53: Calculation of time from activation time 21 to sunrise time 22 S54: Calculation of electric energy (capacitor voltage) required from activation time 21 to sunrise time 22 S55 : Measure capacitor voltage S56: Less than rest voltage?
S58: Night sleep process S59: Startup time?
S60: Startup start processing

Claims

An energy harvesting wireless system that transmits the data acquired by the sensor as it is or after processing it wirelessly,
A power generation unit that receives sunlight and generates electric power;
A capacitor for storing the power;
A voltage monitoring unit for monitoring the voltage of the capacitor;
A wireless unit that wirelessly transmits the data by the electric power stored in the capacitor;
A control device;
A storage device for storing information used in the control device,
The control device includes:
A first means for controlling the system to at least two states: an active state in which the wireless unit can transmit the data wirelessly; and a sleep state in which power consumption is lower than the active state;
A second means for determining a sunrise time based on the output of the voltage monitoring unit and storing it in the storage device;
Third means for obtaining a start time (start time) of the start state stored in the storage device;
A fourth means for determining the anteroposterior relationship between the activation time and the sunrise time stored in the storage device;
When the activation time is the same as or later than the sunrise time, the activation state is set on condition that the voltage monitored by the voltage monitoring unit falls below a first threshold or reaches a predetermined time. A fifth means for switching to the dormant state,
If the activation time is earlier than the sunrise time, the voltage monitored by the voltage monitoring unit falls below a second threshold value that is greater than the first threshold value, or the voltage monitored by the voltage monitoring unit is Sixth means for switching from the activated state to the hibernated state on the condition that the time falls below the second threshold;
A seventh means for adding a value calculated based on a time interval between the activation time and the sunrise time to the first threshold, generating the second threshold, and storing the second threshold in the storage device; Have
Energy generation wireless system.
The storage device
Storing the voltage drop rate of the capacitor per unit time as the startup state voltage drop rate when the system is in the startup state with the power stored in the capacitor;
The seventh means includes
Generating the second threshold using the startup state voltage drop rate;
The energy generation type wireless system according to claim 1.
The seventh means includes
The activation state voltage drop rate is integrated in the time interval between the activation time and the sunrise time, and a positive value of 0 or more is added as a margin to generate the second threshold value.
The energy generation type wireless system according to claim 2.
The control device includes:
Determining the sunset time based on the output of the voltage monitoring unit, storing the voltage of the capacitor at the sunset time in the storage device;
The storage device
Storing the voltage drop rate of the capacitor per unit time as a dormant voltage drop rate when the system is put into the dormant state with the power stored in the capacitor;
The seventh means includes
Further using the voltage of the capacitor and the quiescent voltage drop rate at the sunset time to generate the second threshold;
The energy generation type wireless system according to claim 3.
The control device includes:
The time when the voltage monitored by the voltage monitoring unit falls below the second threshold is calculated from the second threshold, the voltage of the capacitor at the sunset time, and the starting state voltage drop rate, and the time when the voltage falls below the second threshold. Is stored in the storage device,
The sixth means includes
Switch from the activated state to the dormant state using the time less than that stored in the storage device,
The energy generation type wireless system according to claim 4.
The storage device
Storing the voltage drop rate of the capacitor per unit time as a dormant voltage drop rate when the system is put into the dormant state with the power stored in the capacitor;
Storing the maximum voltage that can be stored in the capacitor as the capacitor maximum voltage;
The seventh means includes
Using the capacitor maximum voltage and the quiescent voltage drop rate further to generate the second threshold;
The energy generation type wireless system according to claim 3.
The control device includes:
The time when the voltage monitored by the voltage monitoring unit falls below the second threshold is calculated from the second threshold, the capacitor maximum voltage, and the startup state voltage drop rate, and the time when the voltage is lower is the storage device. Remember
The sixth means includes
Switch from the activated state to the dormant state using the time less than that stored in the storage device,
The energy generation type wireless system according to claim 6.
The second means includes
Periodically determine the sunrise time,
The fourth means includes
Periodically determine the context of the sunrise time,
The seventh means includes
Periodically generating the second threshold and storing it in the storage device;
The energy generation type wireless system according to claim 3.
The second means includes
Determine the sunrise time once a day,
The fourth means includes
Once a day, determine the context of the sunrise time,
The seventh means includes
Generating the second threshold value once a day and storing it in the storage device;
The energy generation type wireless system according to claim 8.
A power generation unit that generates power using sunlight as an energy source;
A power storage unit for storing the power;
A wireless unit for transmitting signals wirelessly;
A control device for controlling the radio unit;
A storage device for storing information used in the control device and a timer capable of measuring time;
The control device includes:
A first means for controlling the apparatus to at least two states: an active state in which the wireless unit transmits a signal wirelessly; and a sleep state in which power consumption is lower than the active state;
A second means for acquiring a start time (start time) of the start state stored in the storage device;
A third means for obtaining the sunrise time;
A fourth means for controlling the start timing of the hibernation state based on the activation time and the sunrise time;
An energy generation type wireless device having
A voltage monitoring unit for monitoring the voltage of the power storage unit;
The fourth means includes
Means for determining the anteroposterior relationship between the activation time and the sunrise time;
If the activation time is earlier than the sunrise time, means for calculating the amount of power required to maintain the activation state from the activation time to the sunrise time;
Means for calculating a voltage (resting voltage) of the power storage unit that is a condition for starting the hibernation state based on the required electric energy;
Means for starting the hibernation state at a timing when the voltage monitoring unit determines that the voltage of the power storage unit is equal to or lower than the hibernation voltage,
The energy generation type wireless device according to claim 10.
The third means includes
Determine the sunrise time based on the power generation state of the power generation unit,
The determined sunrise time is stored in the storage device every day,
The fourth means includes
Processing using the latest sunrise time stored in the storage device;
The energy-generating wireless device according to claim 11.
The fourth means includes
When the start time is later than the sunrise time, the start state is lower than the stop voltage, and at the timing when the voltage monitoring unit determines that the voltage of the power storage unit is equal to or lower than the start voltage, the stop state Means for initiating
The energy generation type wireless device according to claim 12.
The power storage unit is a capacitor,
The storage device
Stores the starting voltage drop rate of the capacitor in the starting state before the sunrise time,
The fourth means includes
Calculate the required power amount by calculation using the startup voltage drop rate, the startup time, and the sunrise time,
A value obtained by adding a voltage corresponding to at least the required power amount to the starting voltage is calculated as the resting voltage.
The energy generation type wireless device according to claim 13.
A power generation unit for obtaining power for driving the wireless device from the energy of sunlight;
A power storage unit for storing the power generated by the power generation unit;
A voltage monitoring unit that measures the amount of power stored in the power storage unit and outputs voltage information;
A timer that outputs time information;
A wireless unit for communicating with other wireless devices;
A memory that records the sunrise time and start-up time;
The power generation unit, the power storage unit, the voltage monitoring unit, the timer, the radio unit, and a control device for controlling the memory,
The control device includes:
Means for calculating the sunrise time and recording it in the memory;
Means for calculating the amount of power consumed by the power generation unit, the power storage unit, the voltage monitoring unit, the timer, the radio unit, the memory, and the control device in the startup state from the startup time to the sunrise time; ,
Means for calculating the amount of power consumed in a sleep state that suppresses power consumption of the power storage unit by stopping a part of functions of the voltage monitoring unit, the timer, the radio unit, the memory, and the control device; ,
Means for measuring a voltage drop rate of the power storage unit per unit time when only the energy stored in the power storage unit is in the activated state;
Means for measuring a voltage drop rate of the power storage unit per unit time when only the energy stored in the power storage unit is in the dormant state;
An energy generation type wireless device having