JP2019030097A - Electric power supply - Google Patents

Abstract

To provide an electric power supply capable of supplying electric power with different priorities for a plurality of functions.SOLUTION: An electric power supply according to an embodiment comprises: a solar battery; a first accumulation unit; a second accumulation unit; a first charging unit that charges the first accumulation unit with electric power generated by the solar battery; and a second charging unit that charges the second accumulation unit from the first accumulation unit, and regulates the charging to the second accumulation unit from the first accumulation unit in response to a first control signal generated in accordance with an operation state of a load of the second accumulation unit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power supply device.

  A solar cell converts light energy into electrical energy and outputs it using the photovoltaic effect of a semiconductor. Therefore, the output changes as the incident light changes. Further, the output voltage and efficiency of the solar cell change depending on the output current. For this reason, when a solar cell is used as an independent power source, generally, as described in Patent Document 1 and Patent Document 2, a solar cell is a power storage device such as a capacitor or a secondary battery, and charging of the power storage device. Used in combination with a voltage conversion circuit for controlling the voltage. Further, there is a case where Maximum Power Point Tracking (MPPT) control is performed in a voltage conversion circuit or the like.

  On the other hand, some electronic control devices that operate using a solar cell as a power source have a plurality of types of functions. In addition, with regard to a plurality of functions, priority (priority) may be different for each function. For example, when the electronic control device has three functions of microcomputer operation, sensing, and wireless communication, the microcomputer operation priority is the highest (high), the sensing priority is medium, and the wireless communication priority is Sometimes it is low. For example, when the microcomputer is not operating, all functions are stopped, so the priority is high. In addition, when performing sensing periodically, data loss occurs when sensing cannot be performed. Therefore, in order to perform all the functions, a lot of electric power is required, and the solar cell needs to be enlarged. However, the use of a solar cell loses the merit that it can be made compact without requiring an external power source.

JP 2012-105509 A JP 2011-234486 A

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a power supply apparatus that can supply power with different priorities for a plurality of functions.

  In order to solve the above problems, one embodiment of the present invention includes a solar battery, a first power storage unit, a second power storage unit, and a first charging unit that charges the first power storage unit with the generated power of the solar cell; Charging the second power storage unit from the first power storage unit, and from the first power storage unit according to a first control signal generated according to an operating state of a load of the second power storage unit And a second charging unit that limits charging to the second power storage unit.

  One embodiment of the present invention is the power supply device described above, wherein the second charging unit includes a switch that cuts off a circuit between the first power storage unit and the second power storage unit in response to the first control signal. In addition, the power consumption of the load periodically changes between large and small, and the first control signal is generated so as to cut off the switch during a period when the power consumption is large.

  One embodiment of the present invention is the power supply device, wherein the solar cell, the first power storage unit, the second power storage unit, the first charging unit, and the second charging unit are formed in a film shape. ing.

  One embodiment of the present invention is the power supply device described above, further including a control unit that generates the first control signal in accordance with an operating state of the load of the second power storage unit.

  One embodiment of the present invention is the above-described power supply device, further including a sensor that is the load of the second power storage unit and detects a predetermined physical quantity.

  One embodiment of the present invention is the power supply device described above, wherein the third power storage unit and the third power storage unit are charged from the second power storage unit, and the second load of the third power storage unit A third charging unit that restricts charging from the second power storage unit to the third power storage unit according to a second control signal generated according to the operation state of the second power supply unit, and the second load, the predetermined information The communication unit further communicates.

  One embodiment of the present invention is the power supply device, wherein the first control signal is in accordance with an operating state of the load of the second power storage unit and an operating state of the second load of the third power storage unit. Is generated.

  According to the present invention, for example, power can be supplied from the first power storage unit to a function having a high priority, and power can be supplied from the second power storage unit to a function having a low priority. That is, according to the present invention, power can be supplied with different priorities for a plurality of functions.

It is a block diagram which shows the structural example of the electronic control apparatus which concerns on one Embodiment of this invention. 3 is a flowchart for explaining an operation example of the electronic control device 1 shown in FIG. 1. 3 is a flowchart for explaining an operation example of the electronic control device 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1. 3 is a timing chart for explaining an operation example of the electronic control unit 1 shown in FIG. 1.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration example of an electronic control device 1 according to an embodiment of the present invention. The electronic control device 1 shown in FIG. 1 includes a load unit 2 and a power supply unit 3. The load unit 2 includes a microcomputer 4, a sensor 5, and a wireless device 6. The power supply unit 3 includes a solar cell 7, a booster circuit 8, a charging unit 9, a charging unit 10, and capacitors C1, C2, and C3. The charging unit 9 includes a diode D1 and a switch S1. The charging unit 10 includes a diode D2 and a switch S2.

  The microcomputer 4 includes a CPU (central processing unit), a storage device such as a main storage device and an auxiliary storage device, an input / output device, and the like, and a predetermined operation is performed when the CPU executes a program stored in the auxiliary storage device. I do. For example, the microcomputer 4 controls the start and stop of the sensor 5 or inputs a detection signal of the sensor 5 and stores it in the storage device as sensor data. Further, the microcomputer 4 controls activation and stop of the wireless device 6 and transmits stored sensor data from the wireless device 6 to a predetermined communication destination. Further, the microcomputer 4 connects (turns on) or opens (turns off) the switch S1 included in the power supply unit 3 by outputting a predetermined control signal to the S1 control line. Further, the microcomputer 4 outputs a predetermined control signal to the S2 control line to connect or open the switch S2 included in the power supply unit 3. Further, the microcomputer 4 includes a terminal voltage V1 (hereinafter also referred to as voltage V1) of the capacitor C1 included in the power supply unit 3, a terminal voltage V2 (hereinafter also referred to as voltage V2) of the capacitor C2, and a terminal voltage V3 (hereinafter referred to as voltage V2) of the capacitor C3. , Also referred to as voltage V3). Further, the microcomputer 4 operates using DC power charged in the capacitor C1 as a power source.

  The microcomputer 4 of this embodiment starts the sensor 5 intermittently with a predetermined period. When the sensor 5 is activated, the microcomputer 4 controls the switches S1 and S2 to be opened. Moreover, the microcomputer 4 starts the radio | wireless machine 6 intermittently with a predetermined period. When the wireless device 6 is activated, the microcomputer 4 controls the switches S1 and S2 to be opened. In other words, in the present embodiment, the power consumption of the sensor 5 and the wireless device 6 that are the loads of the power supply unit 3 periodically changes between large and small. Further, the switch S1 and the switch S2 are controlled to be open during the period when the power consumption is large, and the switch S1 and the switch S2 cut off the circuit between the capacitors C1 to C3.

  In this embodiment, when the terminal voltage V1 of the capacitor C1 is within the operable range of the microcomputer 4, the microcomputer 4 is always operating in a standby state. And the microcomputer 4 starts the sensor 5 for every fixed time. The microcomputer 4 opens the switches S1 and S2 when the sensor 5 is activated. Further, the microcomputer 4 activates the wireless device 6 at a predetermined timing. Similarly, when starting the wireless device 6, the microcomputer 4 opens the switches S1 and S2. In addition, the microcomputer 4 keeps the switches S1 and S2 open when the predetermined voltage in the capacitors C1 to C3 becomes equal to or lower than the specified value after startup.

  The sensor 5 detects a predetermined physical quantity and outputs a signal indicating the detection result to the microcomputer 4. The sensor 5 operates using DC power charged in the capacitor C2 as a power source. In addition, the sensor 5 is activated and enters an operation state where sensing is performed, or stops and enters a non-operation state where no sensing is performed, or a standby state according to control by the microcomputer 4.

  The wireless device 6 is controlled by the microcomputer 4 and transmits data input from the microcomputer 4 to a predetermined communication destination via a predetermined communication line. The communication line is a wireless LAN (local area network) or public network communication line. The radio device 6 operates using DC power charged in the capacitor C3 as a power source. In addition, the wireless device 6 is activated and enters an operation state where wireless communication is performed, or stops and enters a non-operation state where no wireless communication is performed or a standby state, according to control by the microcomputer 4.

  The solar cell 7 is, for example, a one-cell solar cell, and outputs DC power corresponding to the illuminance of incident light with an output voltage of about 0.5V. The booster circuit 8 boosts the output voltage of the solar cell 7 to about 1.5V to 3V and converts it to a voltage sufficient to drive a general low-voltage electronic circuit. In this case, the booster circuit 8 converts the output voltage of the solar cell 7 into a predetermined voltage, and charges the capacitor C1 with the electric power generated by the solar cell 7. When the switch S1 is connected by the microcomputer 4, the charging unit 9 charges the capacitor C2 using the capacitor C1 as a power source via the diode D1 and the switch S1. In addition, when the switch S1 is opened by the microcomputer 4, the charging unit 9 stops charging from the capacitor C1 to the capacitor C2. When the switch S2 is connected by the microcomputer 4, the charging unit 10 charges the capacitor C3 using the capacitor C2 as a power source via the diode D2 and the switch S2. In addition, when the switch S2 is opened by the microcomputer 4, the charging unit 10 stops charging from the capacitor C2 to the capacitor C3.

  The switches S1 and S2 may be configured by a semiconductor element such as a field effect transistor (FET), or may be configured using a mechanical contact such as a relay. The S1 control line connecting the microcomputer 4 and the switch S1 and the S2 control line connecting the switch S2 are provided with a gate voltage drive circuit and a coil drive circuit (not shown). The microcomputer 4, the sensor 5, the wireless device 6, the booster circuit 8, and the capacitors C1 to C3 are connected to a common ground. Moreover, the negative electrode of the solar cell 7 may be connected to a common ground.

  Further, the switches S1 and S2 may operate so as to control the charging current to a constant value in the connected state, or operate so as to control the charging current to a constant value smaller than the connected state in the open state. That is, the switches S1 and S2 may operate so as to control the charging current to a constant value (or a predetermined value or less) when connected, or may operate so as to flow a weak charging current when opened. In this case, the charging current may be controlled by the switches S1 and S2, or the diodes D1 and D2 may be constant current diodes, or may be replaced by diodes D1 and D2 or connected in series. May be.

  The embodiment of the present invention is not limited to the configuration shown in FIG. For example, the charging unit 10 and the capacitor C3 may be omitted, and the power source of the wireless device 6 may be the capacitor C2. Moreover, the solar cell 7 may be comprised by the single cell, and may be comprised by connecting a some cell in series or in parallel. The step-up circuit 8 may be replaced with a step-down circuit or a step-up / step-down circuit that performs step-up and step-down. Further, some or all of the capacitors C1 to C3 may be replaced with a secondary battery or connected in parallel with the secondary battery. The wireless device 6 may be replaced with, for example, a wired communication device. Further, the booster circuit 8 or the like may have a function of performing MPPT control, for example.

  The power supply unit 3 can be configured as follows, for example. That is, the solar cell 7, the booster circuit 8, the charging unit 9, the charging unit 10, and the capacitors C <b> 1 to C <b> 3 included in the power supply unit 3 are printed electronics (printed circuit forming technology) on a substrate that is a thin and soft film insulator. ) Can be used to form a film by applying various organic or inorganic materials.

  In the present embodiment, for example, the power supply unit 3 may be commercialized as a power supply device, or a microcomputer may be provided in the power supply unit 3 so that the microcomputer has some or all of the functions of the microcomputer 4 described above. Good. Further, the sensor 5 and the wireless device 6 may be provided in the power supply unit 3.

  Next, an operation example of the electronic control unit 1 shown in FIG. 1 will be described with reference to FIGS. 2 and 3 are flowcharts showing the flow of processing executed by the microcomputer 4. 4, FIG. 6 and FIG. 8 are timing charts showing temporal changes in the terminal voltages V1 to V3 of the capacitors C1 to C3. 5, FIG. 7 and FIG. 9 are timing charts showing temporal changes in the current consumption of the load section 2.

  Each process shown in FIG. 2 and FIG. 3 is repeatedly executed by the microcomputer 4 at a constant cycle after the microcomputer 4 is activated. The process shown in FIG. 2 and the process shown in FIG. 3 may be executed in the same cycle or may be executed in different cycles. In each process shown in FIG. 2 and FIG. 3, the voltages Va to Vf used as determination criteria have the following relationship as shown in FIG. That is, the use limit voltage Va has a relationship of the operation start voltage Vb and Va <Vb. The operation start voltage Vb is the lowest voltage at which the microcomputer 4, the sensor 5 and the wireless device 6 can start operation. When the power supply voltage is higher than this voltage, the microcomputer 4, the sensor 5 and the wireless device 6 are activated. Can work. In this example, the operation start voltage Vb is the same for the microcomputer 4, the sensor 5, and the wireless device 6. The use limit voltage Va is a voltage that may cause the microcomputer 4, the sensor 5, and the wireless device 6 that are operating to stop operating normally when the voltage becomes equal to or lower than this voltage. The S2 open voltage Vc is a reference value for the microcomputer 4 to open the switch S2 when the voltage V2 is equal to or lower than this voltage, and there is a relationship of Vb <Vc. The S1 open voltage Vd is a reference value by which the microcomputer 4 opens the switch S1 when the voltage V1 is equal to or lower than this voltage. The S2 connection voltage Ve is a reference value with which the microcomputer 4 connects the switch S2 when the voltage V2 is equal to or higher than this voltage. The S1 open circuit voltage Vd and the S2 connection voltage Ve are equal, and there is a relationship of Vd = Ve> Vc. The S1 connection voltage Vf is a reference value with which the microcomputer 4 connects the switch S1 when the voltage V1 is equal to or higher than this voltage, and has a relationship of Vf> Vd = Ve.

  Next, the flow of processing shown in FIGS. 2 and 3 will be described. It is assumed that the switch S1 and the switch S2 are in an open (off) state during startup. Further, it is assumed that both the flag FV2 indicating whether or not the voltage V2 is within the operable range and the flag FV3 indicating whether or not the voltage V3 is within the operable range at the time of start-up. The flag FV2 is turned on when the voltage V2 becomes equal to or higher than the operation start voltage Vb, and is turned off when it becomes equal to or lower than the use limit voltage Va. The flag FV3 is turned on when the voltage V3 becomes equal to or higher than the operation start voltage Vb, and turned off when the voltage V3 becomes equal to or lower than the use limit voltage Va.

  First, the flow of processing shown in FIG. 2 will be described. In the process shown in FIG. 2, the microcomputer 4 first determines whether or not the voltage V1 is equal to or higher than the S1 connection voltage Vf (step S101). If the voltage V1 is equal to or higher than the S1 connection voltage Vf (YES in step S101), the microcomputer 4 connects the switch S1 (step S102). Alternatively, the microcomputer 4 maintains the connection state of the switch S1 (step S102).

  Next, the microcomputer 4 determines whether or not the voltage V1 is equal to or lower than the S1 open circuit voltage Vd (step S103). If the voltage V1 is equal to or lower than the S1 open voltage Vd (YES in step S103), the microcomputer 4 opens the switch S1 (step S104). Alternatively, the microcomputer 4 maintains the open state of the switch S1 (step S104).

  Next, the microcomputer 4 determines whether or not the voltage V2 is equal to or higher than the S2 connection voltage Ve (step S105). If the voltage V2 is equal to or higher than the S2 connection voltage Ve (YES in step S105), the microcomputer 4 connects the switch S2 (step S106). Alternatively, the microcomputer 4 maintains the connection state of the switch S2 (step S106).

  Next, the microcomputer 4 determines whether or not the voltage V2 is equal to or lower than the S2 open circuit voltage Vc (step S107). When the voltage V2 is equal to or lower than the S2 open voltage Vc (YES in step S107), the microcomputer 4 opens the switch S2 (step S108). Alternatively, the microcomputer 4 maintains the open state of the switch S2 (step S108).

  Next, the microcomputer 4 determines whether or not the voltage V2 is equal to or higher than the operation start voltage Vb (step S109). If voltage V2 is equal to or higher than operation start voltage Vb (YES in step S109), microcomputer 4 turns on flag FV2 (step S110). Alternatively, the microcomputer 4 maintains the on state of the flag FV2 (step S110).

  Next, the microcomputer 4 determines whether or not the voltage V2 is equal to or lower than the use limit voltage Va (step S111). If the voltage V2 is equal to or lower than the use limit voltage Va (YES in step S111), the microcomputer 4 turns off the flag FV2 (step S112). Alternatively, the microcomputer 4 maintains the flag FV2 in the off state (step S112).

  Next, the microcomputer 4 determines whether or not the voltage V3 is equal to or higher than the operation start voltage Vb (step S113). If voltage V3 is equal to or higher than operation start voltage Vb (YES in step S113), microcomputer 4 turns on flag FV3 (step S114). Alternatively, the microcomputer 4 keeps the flag FV3 on (step S114).

  Next, the microcomputer 4 determines whether or not the voltage V3 is equal to or lower than the use limit voltage Va (step S115). If voltage V3 is equal to or lower than use limit voltage Va (YES in step S115), microcomputer 4 turns off flag FV3 (step S116). Alternatively, the microcomputer 4 maintains the flag FV3 in the off state (step S116).

  Next, the process flow shown in FIG. 3 will be described. In the process shown in FIG. 3, the microcomputer 4 first determines whether or not the flag FV2 is on (step S201). If the flag FV2 is on (YES in step S201), the microcomputer 4 determines whether it is the sensor activation timing (step S202). In the present embodiment, when the sensor 5 is operable, the microcomputer 4 activates the sensor 5 at a predetermined cycle and acquires sensor data. In step S202, the microcomputer 4 determines that it is the sensor activation timing at a timing corresponding to the predetermined cycle (YES in step S202).

  If it is determined that it is the sensor activation timing (YES in step S202), the microcomputer 4 opens the switch S1 and the switch S2 (step S203). If the switch S1 or the switch S2 is already open in step S203, the microcomputer 4 maintains the open state. Next, the microcomputer 4 activates the sensor 5 (step S204). Next, the microcomputer 4 determines whether or not a condition for stopping the sensor 5 is satisfied (step S205). The condition for stopping the sensor 5 is, for example, that when the microcomputer 4 can normally receive a signal indicating the detection result from the sensor 5, the time required for the output signal of the sensor 5 to stabilize after the sensor 5 is activated has elapsed. Or if it is recognized that some abnormality has occurred. The microcomputer 4 waits until the condition for stopping the sensor 5 is satisfied (NO in step S205), and when the condition for stopping the sensor 5 is satisfied (YES in step S205), stops the sensor 5 ( Step S206). The microcomputer 4 uses the sensor data as a signal indicating a detection result normally received from the sensor 5 or a signal acquired after the time required for the output signal of the sensor 5 to stabilize after the sensor 5 is activated. For example, the information is stored in a predetermined storage device in association with information indicating the acquisition time.

  If the sensor 5 is stopped in step S206, or if it is determined that it is not the sensor activation timing (NO in step S202), or if the flag FV2 is off (NO in step S201), the microcomputer 4 It is determined whether or not the flag FV3 is on (step S207). If the flag FV3 is on (YES in step S207), the microcomputer 4 determines whether or not it is the wireless device activation timing (step S208). In the present embodiment, when the wireless device 6 is operable, the microcomputer 4 activates the wireless device 6 at a predetermined cycle and transmits sensor data and the like to a predetermined communication destination. In step S208, the microcomputer 4 determines that it is the wireless device activation timing at a timing corresponding to the predetermined cycle (YES in step S208).

  If it is determined that the wireless device activation timing is reached (YES in step S208), the microcomputer 4 opens the switch S1 and the switch S2 (step S209). If the switch S1 or the switch S2 is already open in step S209, the microcomputer 4 maintains the open state. Next, the microcomputer 4 activates the wireless device 6 (step S210). Next, the microcomputer 4 determines whether or not a condition for stopping the wireless device 6 is satisfied (step S211). The condition for stopping the wireless device 6 is, for example, that when the microcomputer 4 receives a notification from the wireless device 6 that the sensor data or the like has been transmitted normally, the wireless device 6 is instructed to transmit the sensor data. This corresponds to the case where the time required for completion has elapsed or when it is recognized that some abnormality has occurred. The microcomputer 4 waits until the condition for stopping the wireless device 6 is satisfied (NO in step S211). If the condition for stopping the wireless device 6 is satisfied (YES in step S211), the microcomputer 4 is turned off. Stop (step S212).

  If the wireless device 6 is stopped in step S212, or if it is determined that it is not the wireless device activation timing (NO in step S208), or if the flag FV3 is off (NO in step S207), the microcomputer 4 Ends the process shown in FIG.

  Next, an operation example of the electronic control device 1 shown in FIG. 1 will be described with reference to a timing chart showing time changes of the terminal voltages V1 to V3 of the capacitors C1 to C3 shown in FIG. In the example illustrated in FIG. 4, charging is started by power generated by the solar cell 7 from time t <b> 0 in a state where the capacitors C <b> 1 to C <b> 3 are not charged at all as an initial state. Further, the switches S1 and S2 are set in an open state in the initial state. After the time t0, the capacitor C1 is first charged. When the voltage V1 rises and reaches the operation start voltage Vb, the microcomputer 4 is activated (time t1). At this time, the power charged in the capacitor C1 is consumed, but the power generation amount of the solar battery 7 is sufficiently higher than the consumption amount of the microcomputer 4. After time t1, the capacitor C1 is continuously charged and the voltage V1 continues to rise.

  The microcomputer 4 executes the processing shown in FIGS. 2 and 3 after performing predetermined initial settings and the like after startup.

(1) Time t1 to time t2: In FIG. 4, it is assumed that the voltage V1 has not reached the time t2 at which the voltage V1 becomes equal to or higher than the S1 connection voltage Vf after the microcomputer 4 is activated at the time t1. In this case, since the voltage V1 is less than the S1 connection voltage Vf, the voltage V2 is zero, and the voltage V3 is zero, when the microcomputer 4 executes the process shown in FIG. 2, the switch S1 is opened, the switch S2 is opened, and the flag FV2 is off. The flag FV3 is set to OFF (“NO” in step S101 → “YES” in step S103 → step S104 → “NO” in step S105 → “YES” in step S107 → step S108 → step S109 “NO” → “YES” in step S111 → step S112 → “NO” in step S113 → “YES” in step S115 → step S116). Further, when the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is not activated, and the wireless device 6 is not activated (“NO” in step S201 → “NO” in step S207).

(2) Time t2: In FIG. 4, it is assumed that the voltage V1 becomes equal to or higher than the S1 connection voltage Vf at time t2. In this case, the voltage V1 is equal to or higher than the S1 connection voltage Vf, the voltage V2 is zero, and the voltage V3 is zero. Therefore, when the microcomputer 4 executes the process shown in FIG. 2, the switch S1 is connected, the switch S2 is opened, The flag FV3 is set to OFF (“YES” in step S101 → “NO” in step S102 → “NO” in step S103 → “NO” in step S105 → “YES” in step S107 → step S108 → step S109 “NO” → “YES” in step S111 → step S112 → “NO” in step S113 → “YES” in step S115 → step S116). Further, when the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is not activated, and the wireless device 6 is not activated (“NO” in step S201 → “NO” in step S207). Here, charging of the capacitor C2 is started. Since charging of the capacitor C2 is started, the voltage V2 starts to rise.

(3) Time t3: Next, it is assumed that the voltage V2 becomes equal to or higher than the operation start voltage Vb at time t3. The voltage V1 is assumed to be lower than the S1 connection voltage Vf and higher than the S1 open voltage Vd. The voltage V3 is zero. Here, the sensor 5 is in an operable state. When the microcomputer 4 executes the processing shown in FIG. 2, the switch S1 is connected, the switch S2 is opened, the flag FV2 is turned on, and the flag FV3 is turned off (“NO” in step S101 → “NO” in step S103) → “NO” in Step S105 → “YES” in Step S107 → Step S108 → “YES” in Step S109 → Step S110 → “NO” in Step S111 → “NO” in Step S113 → “YES” in Step S115 → Step S116 ). When the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is activated at the sensor activation timing and the wireless device 6 is not activated (“YES” in step S201 → “YES” in step S202 to step S206 or step S202). “NO” in S202 → “NO” in Step S207).

(4) Time t4: Next, it is assumed that the voltage V2 becomes equal to or higher than the S2 connection voltage Ve at time t4. The voltage V1 is assumed to be lower than the S1 connection voltage Vf and higher than the S1 open voltage Vd. The voltage V3 is zero. Further, it is assumed that the voltage V2 is larger than the use limit voltage Va. Here, the switch S2 is connected. When the microcomputer 4 executes the process shown in FIG. 2, the switch S1 is connected, the switch S2 is connected, the flag FV2 is turned on, and the flag FV3 is turned off (“NO” in step S101 → “NO” in step S103) → “YES” in step S105 → “NO” in step S106 → “NO” in step S107 → “YES” in step S109 → “NO” in step S111 → “NO” in step S113 → “YES” in step S115 → step S116 ). When the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is activated at the sensor activation timing and the wireless device 6 is not activated (“YES” in step S201 → “YES” in step S202 to step S206 or step S202). “NO” in S202 → “NO” in Step S207). Here, charging of the capacitor C3 is started. Since charging of the capacitor C3 is started, the voltage V3 starts to rise.

(5) Time t5: Next, it is assumed that the voltage V3 becomes equal to or higher than the operation start voltage Vb at time t5. The voltage V1 is assumed to be lower than the S1 connection voltage Vf and higher than the S1 open voltage Vd. The voltage V2 is assumed to be less than the S2 connection voltage Ve and greater than the S2 open voltage Vc. Here, the wireless device 6 is in an operable state. When the microcomputer 4 executes the processing shown in FIG. 2, the switch S1 is connected, the switch S2 is connected, the flag FV2 is turned on, and the flag FV3 is turned on (“NO” in step S101 → “NO” in step S103) → “NO” in Step S105 → “NO” in Step S107 → “YES” in Step S109 → Step S110 → “NO” in Step S111 → “YES” in Step S113 → “NO” in Step S114 → “NO” in Step S115) When the microcomputer 4 executes the processing shown in FIG. 3, the sensor 5 is activated at the sensor activation timing, and the wireless device 6 is activated at the wireless device activation timing (“YES” in step S201 → in step S202). From “YES” to “NO” in step S206 or step S202 → “YES” in step S207 → “YES” in step S208 to “NO” in step S212 or step S208).

(6) Time t7: Next, it is assumed that the generated power of the solar cell 7 is stopped or short after time t6, and the voltage V2 becomes equal to or lower than the S2 open voltage Vc at time t7. The voltage V1 is assumed to be lower than the S1 connection voltage Vf and higher than the S1 open voltage Vd. Further, it is assumed that the voltage V2 is larger than the use limit voltage Va. Further, it is assumed that the voltage V3 is larger than the use limit voltage Va. When the microcomputer 4 executes the process shown in FIG. 2, the switch S1 is connected, the switch S2 is opened, the flag FV2 is turned on, and the flag FV3 is turned on (“NO” in step S101 → “NO” in step S103). → “NO” in Step S105 → “YES” in Step S107 → Step S108 → Step S109 “YES” → Step S110 → “NO” in Step S111 → “YES” in Step S113 → “NO” in Step S114 → Step S115 ). When the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is activated at the sensor activation timing, and the wireless device 6 is activated at the wireless device activation timing (“YES” in step S201 → “YES” in step S202). From “NO” in step S206 or step S202 to “YES” in step S207 → “YES” in step S208 to “NO” in step S212 or step S208).

(7) Time t8: Next, it is assumed that the voltage V3 becomes equal to or lower than the use limit voltage Va at time t8. The voltage V1 is assumed to be lower than the S1 connection voltage Vf and higher than the S1 open voltage Vd. Further, it is assumed that the voltage V2 is larger than the use limit voltage Va. When the microcomputer 4 executes the processing shown in FIG. 2, the switch S1 is connected, the switch S2 is opened, the flag FV2 is turned on, and the flag FV3 is turned off (“NO” in step S101 → “NO” in step S103) → “NO” in Step S105 → “YES” in Step S107 → Step S108 → “YES” in Step S109 → Step S110 → “NO” in Step S111 → “NO” in Step S113 → “YES” in Step S115 → Step S116 ). When the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is activated at the sensor activation timing and the wireless device 6 is not activated (“YES” in step S201 → “YES” in step S202 to step S206 or step S202). “NO” in S202 → “NO” in Step S207).

(8) Time t9: Next, assume that the voltage V1 becomes equal to or lower than the S1 open circuit voltage Vd at time t9. In this case, it is assumed that the voltage V2 is larger than the use limit voltage Va. When the microcomputer 4 executes the process shown in FIG. 2, the switch S1 is opened, the switch S2 is opened, the flag FV2 is turned on, and the flag FV3 is turned off (“NO” in step S101 → “YES” in step S103). → Step S104 → “NO” in Step S105 → “YES” in Step S107 → Step S108 → Step S109 “YES” → Step S110 → “NO” in Step S111 → “NO” in Step S113 → “YES” in Step S115 → Step S116). When the microcomputer 4 executes the process shown in FIG. 3, the sensor 5 is activated at the sensor activation timing and the wireless device 6 is not activated (“YES” in step S201 → “YES” in step S202 to step S206 or step S202). “NO” in S202 → “NO” in Step S207).

  The operation example shown in FIG. 4 assumes a situation in which the voltage decreases and the operation stops when the sensor 5 and the radio device 6 operate when the power generated by the solar cell is not sufficient and charging is completed. Yes. As an initial state, charging starts from a state where the capacitors C1 to C3 are not charged at all (time t0), and the capacitor C1 is charged first. When the voltage V1 rises and the voltage V1 reaches the operation start voltage Vb, the microcomputer 4 is activated (time t1). At this time, the electric power charged in the capacitor C1 is consumed. If the power generation amount of the solar battery 7 is sufficiently higher than the consumption amount of the microcomputer 4, the capacitor C1 is continuously charged and the voltage V1 increases. to continue. At this time, both the switch S1 and the switch S2 are open (time t1 to time t2 (not including time t2)). When the voltage V1 reaches the S1 connection voltage Vf, the microcomputer 4 connects the switch S1 and starts charging the capacitor C2 (time t2). Since charging of the capacitor C2 is started, the voltage V2 starts to rise. Assuming that the amount of power generated by the solar cell 7 at this time is not generating enough power to charge the capacitor C2, the voltage V1 starts to decrease. Here, for the sake of simplicity, the rise and fall of the voltage is represented by a straight line, but the actual operation changes suddenly at the time of switching, and the rise and fall of the voltage linearly due to the relationship between the power generation amount and the charge amount. Must not. Although the description has been made from the state in which C1 to C3 are not charged at all, the change of the state does not necessarily occur in the order of the description, and the change of the specific state may occur repeatedly.

  When the voltage V2 starts to rise due to the charging of the capacitor C2 and reaches the S2 connection voltage Ve, the microcomputer 4 connects the switch S2, and charging of the capacitor C3 is started (time t4). Since charging of the capacitor C3 is started, the voltage V3 starts to rise. At this time, assuming that the amount of power generated by the solar cell 7 is not sufficient to charge the capacitor C3, the voltage V1 and the voltage V2 begin to decrease. In FIG. 4, the voltage change caused by the operation of the sensor 5 or the wireless device 6 is not expressed. However, when the sensor 5 or the wireless device 6 operates even when the power generation amount of the solar cell 7 is sufficient. The voltage drops, and after the operation is finished, the voltage rises again.

  The voltage V3 rises and reaches a voltage at which the wireless device 6 can operate at time t5. In this state, all of the microcomputer 4, the sensor 5, and the wireless device 6 are operable. In this state, when the solar cell generates electric power that is higher than the average electric power at which all devices can operate, the voltage V1, the voltage V2, and the voltage V3 can continue to maintain the voltage.

  In the example illustrated in FIG. 4, power generation is stopped at time t6, the sensor 5 and the radio device 6 continue to operate, and the voltage of the capacitors C1 to C3 decreases. When the switches S1 and S2 are all closed, all the voltages decrease. First, the voltage V2 decreases and the switch S2 is opened at time t7 (time t7). Although the capacitor C3 is not charged, the radio device 6 remains operable because the voltage V3 is equal to or higher than the use limit voltage Va.

  When the voltage V3 further decreases and reaches the use limit voltage Va, the wireless device 6 stops its operation, so that the voltage V3 stops decreasing (time t8). At this time, since the switch S2 is opened, it is not charged from other capacitors C1 and C2. Next, when the voltage V1 decreases to the S1 open voltage Vd, the switch S1 is opened and charging of the capacitor C2 is stopped (time t9). However, in this example, since the voltage V2 is equal to or higher than the use limit voltage Va, the operation of the sensor 5 continues.

  After this, when there is still no power generation, the voltage V2 drops to the use limit voltage Va and the sensor 5 stops. Although the voltage V1 continues to gradually decrease, the current consumption of the voltage V1 is sufficiently small, and the microcomputer 4 can continue to operate even when there is no long-term power generation by sufficiently increasing the capacity of the capacitor C1. it can.

  For example, if the capacitor C1 is designed to be about 20 hours, the operation can be continued even when there is no illumination for a long time at night. Similarly, if the capacitor C2 is designed to have a capacity that allows the sensor 5 to continue for 20 hours, the operation can be continued. In this way, when the power is sufficient, the wireless device 6 is used to transmit data. When the power is insufficient, only the measurement by the sensor 5 is continued, and when the power is insufficient, the power is It can be prepared so that the operation can be resumed when it recovers.

  FIG. 5 shows a change over time in current consumption of the load unit 2 during a period (time t5 to t8) in which the sensor 5 and the wireless device 6 can operate in FIG. The microcomputer 4 always consumes P1 power. Further, the sensor power P2 and the wireless power P3 are consumed at a constant time interval T1. FIG. 5 shows normal operation when the voltages of the capacitors C1 to C3 are sufficiently high. In FIG. 4, if the current consumption changes during this period as shown in FIG. 5, the voltage change does not become linear as shown in FIG. 4, but changes in accordance with the period of the current change. Here, only large changes are modeled linearly.

  Next, with reference to FIG. 6 and FIG. 7, an operation example when the voltage V3 of the capacitor C3 decreases to the use limit voltage Va will be described. FIG. 6 is a timing chart showing temporal changes in the terminal voltages V1 to V3 of the capacitors C1 to C3 as in FIG. 4, and FIG. 7 shows that the voltage V3 rises to the operation start voltage Vb at time t10 in FIG. Then, the time change of the consumption current of the load unit 2 corresponding to the period (time t11 to t12) from when it decreases to the use limit voltage Va and increases again to the operation start voltage Vb is shown. In the example shown in FIG. 6 and FIG. 7, after the first wireless transmission at time t11, the power generation amount decreases, the voltage V3 decreases, the voltage V3 of the capacitor C3 decreases, and then recovers at time t12. Yes.

Next, an example of operation when the voltage V2 of the capacitor C2 and the voltage V3 of the capacitor C3 are reduced to the use limit voltage Va will be described with reference to FIGS.
FIG. 8 is a timing chart showing temporal changes in the terminal voltages V1 to V3 of the capacitors C1 to C3 as in FIG. 4, and FIG. 9 is a diagram illustrating the voltage V3 that has increased to the operation start voltage Vb at time t20 in FIG. Corresponding to a period (time t21 to t23) until the voltage V2 drops to the use limit voltage Va (time t22) and then rises to the operation start voltage Vb (time t21). The time change of the consumption current of the load part 2 to perform is shown. In the example shown in FIG. 8 and FIG. 9, after the first wireless transmission before time t21, the amount of power generation decreases, each voltage decreases, the voltage V3 of the capacitor C3 decreases, and the voltage of the capacitor C2 further decreases. V2 drops, and then the voltage V2 of the capacitor C2 is recovered.

  As described above, in the present embodiment, power can be supplied from the power supply unit 3 to the load unit 2 with different priorities for a plurality of functions of the load unit 2. For example, according to the present invention, the power supply unit 3 is configured by a circuit in which a solar battery cell and a charging circuit are connected via a switch and a capacitor that stores two or more electric powers. According to this, the capacitor to be charged and the capacitor to be discharged can be switched by operating the switch from the outside of the power supply unit 3. By allocating capacitors for different uses with different priorities, for example, the remaining amount can be managed for each purpose such as sensing and wireless communication. Further, according to the present embodiment, a safe and ready-to-use harvester power source (a power source that can obtain power in the absence of a power source) that supplies power in order from a higher priority operation can be provided.

  In the present embodiment, the capacitor C1 is an example of the first power storage unit of the present invention. The capacitor C2 is an example of the second power storage unit of the present invention. Capacitor C3 is an example of the third power storage unit of the present invention. The booster circuit 8 is an example of the first charging unit of the present invention. The charging unit 9 charges the second power storage unit from the first power storage unit of the present invention, and the first power storage unit according to the first control signal generated according to the operating state of the load of the second power storage unit It is an example of the 2nd charging part which restricts the charge to the 2nd electrical storage part from. Here, an example of the load of the second power storage unit is the sensor 5. The charging unit 10 charges the third power storage unit from the second power storage unit according to the present invention, and the second power control unit generates the second power according to the second control signal generated according to the operating state of the second load of the third power storage unit. It is an example of the 3rd charging part which restricts the charge from an electrical storage part to the 3rd electrical storage part. Here, an example of the second load is the wireless device 6. The microcomputer 4 is an example of a control unit that generates a first control signal according to the operating state of the load of the second power storage unit. The wireless device 6 is an example of a communication unit that communicates predetermined information of the present invention. The predetermined control signal output to the S1 control line is an example of the first control signal of the present invention. The predetermined control signal output to the S2 control line is an example of the second control signal of the present invention.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design and the like within a scope not departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Electronic controller 2 Load part 3 Power supply part 4 Microcomputer 5 Sensor 6 Radio | wireless machine 7 Solar cell 8 Booster circuit 9, 10 Charging part C1-C3 Capacitor S1, S2 Switch D1, D2 Diode

Claims (7)

Solar cells,
A first power storage unit;
A second power storage unit;
A first charging unit that charges the first power storage unit with power generated by the solar cell;
The second power storage unit is charged from the first power storage unit, and the second power storage unit is charged from the first power storage unit according to a first control signal generated according to an operating state of a load of the second power storage unit. 2 a second charging unit that restricts charging to the power storage unit;
A power supply device comprising: The second charging unit has a switch that cuts off a circuit between the first power storage unit and the second power storage unit in response to the first control signal;
The power consumption of the load periodically changes from large to small,
The power supply device according to claim 1, wherein the first control signal is generated to shut off the switch during a period in which the power consumption is large. The power supply device according to claim 1, wherein the solar cell, the first power storage unit, the second power storage unit, the first charging unit, and the second charging unit are formed in a film shape. 4. The power supply device according to claim 1, further comprising a control unit that generates the first control signal according to an operating state of the load of the second power storage unit. 5. 5. The power supply device according to claim 1, further comprising a sensor that detects the predetermined physical quantity, which is the load of the second power storage unit. 6. A third power storage unit;
Charging the third power storage unit from the second power storage unit, from the second power storage unit according to a second control signal generated according to the operating state of the second load of the third power storage unit A third charging unit that limits charging to the third power storage unit;
The power supply device according to claim 1, further comprising a communication unit that communicates predetermined information as the second load. The power supply device according to claim 6, wherein the first control signal is generated according to an operating state of the load of the second power storage unit and an operating state of the second load of the third power storage unit.

Images