JP6081125B2 - Photovoltaic power generation apparatus and power management system, and power load and measuring apparatus therefor - Google Patents

Description

  The present invention relates to a solar power generation apparatus and a power management system capable of generating power with a power smaller than the maximum power that can be generated in a given environment, and a power load and a measurement apparatus therefor.

  Here, the situation in which power is generated with less power than the maximum power that can be generated in a given environment is when the solar power generator is operated independently during a power outage or when the grid-connected solar power generator is in the distribution system. It is conceivable that the output is suppressed in order to reduce the reverse power flow in response to a request from the administrator. In addition, the solar power generation device or the power management system in the present invention includes a function of taking out power by controlling the direct current voltage and direct current of the solar panel. Moreover, when performing an alternating current output, the inverter function which converts the direct-current power of a solar panel into alternating current power is included. The solar power generation device or power management system according to the present invention assumes both cases where it is installed in a consumer such as a home, a building, a store, or a factory, and when installed in a power plant such as a mega solar.

  FIG. 2 shows the relationship between the DC voltage of the solar panel and the power generation output. The power generation output draws a curve with the maximum value at a certain DC voltage. Here, the maximum value of the power generation output is referred to as the maximum power that can be generated. The curve fluctuates depending on the amount of solar radiation and the panel temperature, but the operation of the solar panel is such that a normal solar power generation device is always clipped to the maximum power that can be generated while monitoring the direct current voltage or direct current of the solar panel. To control. FIG. 3 shows a circuit diagram of a typical photovoltaic power generation apparatus. The output from the solar panel is boosted with a boost chopper and converted to alternating current with an inverter. The measured values of the direct current voltage and direct current of the solar panel are input to the control block, and the opening and closing of the switch S1 is controlled so that it is always clipped to the maximum power that can be generated. The control block converts the direct current into alternating current by PWM control using the switches S2-S5 and outputs it.

  Predict the maximum power that can be generated when a solar power generation device installed in a home is operated independently using the open voltage of the solar cell for monitoring, and when the maximum power that can be generated falls below the set value, A power management system that cuts off a remote switch connected to a power load to reduce power is disclosed in Patent Document 1 below.

  In addition, when the output of the solar power generation device installed at the consumer is estimated based on the measurement result of the solar radiation meter, and combined with the available power of the power storage device, the available power is predicted. Patent Document 2 below discloses a power management system that cuts off a remote switch in order from a low-priority power load based on a preset priority order to reduce power.

  Further, Non-Patent Document 1 below discloses a method for obtaining a target value of a direct current that outputs maximum power using a short-circuit current pulse of a solar cell.

JP-A-9-149554 JP 2008-125295 A

Electrical Engineering D, 121, No. 1, pp. 80-83

  Conventional solar power generators do not know how much power they can use when they operate independently in the home due to a power outage, etc., so if the amount of solar radiation fluctuates due to movement of clouds, etc., power supply capacity May suddenly stop output, or the operation of the device may become unstable.

  Patent Documents 1 and 2 described above describe means for continuing the self-sustained operation by predicting the maximum power that can be generated according to the amount of solar radiation and opening and closing the power supply path of the demand device. It is configured to analyze the measurement result of the meter in the control device and directly operate the switch, however, it cannot be accurately predicted due to the positional deviation between the photovoltaic power generation panel to generate power and the measuring instrument. It is thought that the installation cost will increase due to the additional installation of measuring instruments outdoors. In particular, Patent Document 1 discloses a method for predicting the maximum power that can be generated from the open circuit voltage of the solar cell for monitoring. However, since the open circuit voltage is affected by the panel temperature and an error increases, accurate prediction is possible. I guess it can't be done. Further, regarding Patent Document 2, it is presumed that an accurate prediction cannot be made as in Patent Document 1 because the element of the panel temperature is not taken into consideration. Non-Patent Document 1 discloses a technique for obtaining a target value of a direct current that outputs maximum power, but does not disclose a technique for obtaining maximum power that can be generated. That is, there is a problem that there is no method for accurately predicting the maximum power that can be generated at a low cost when generating power with a power that is smaller than the maximum power that can be generated in an environment where the photovoltaic power generation apparatus is given, such as during self-sustained operation is there.

  In addition, when the ratio of conventional solar power generation equipment to the power supply of the power system is large, the output of solar power generation is reduced during the time period when the amount of solar radiation is large and the power supply is expected to exceed the power demand. Need to be suppressed. At that time, if the solar power output suddenly drops due to changes in the weather, etc., methods of adjusting the power supply such as large-capacity storage battery, pumped-storage power generation, thermal power generation, hydroelectric power generation are considered, but the equipment cost In particular, in the case of thermal power generation, additional fuel costs are required to emit CO2.

  Therefore, if the local power distribution management facility can grasp the information on the maximum power that can be generated by each photovoltaic power generation device in which the output is suppressed, power generation can be suppressed when the output of solar power generation fluctuates due to changes in the weather. A method of performing power leveling by appropriately relaxing the conditions can be considered. However, Patent Document 1, Patent Document 2, and Non-Patent Document 1 have a problem that there is no function of transmitting information on the maximum power that can be generated to the outside.

  The present invention has been achieved in view of the above-described problems in the prior art, and the object thereof is a photovoltaic power generation apparatus and a power management system capable of solving the problems in the prior art, and power for the same. To provide a load and a measuring device.

  In the present invention, in order to achieve the above-described object, for example, there is a solar power generation apparatus having a means for generating power with a power smaller than the maximum power that can be generated in a given environment and a data communication means. And providing a photovoltaic power generation device having a function of transmitting the predicted value of the maximum power generation possible of the solar panel in the environment through the data communication means when generating power with a power smaller than the maximum power generation possible power. Is done.

  According to the present invention described above, a solar power generation device and a power management system capable of solving the problems in the above-described conventional technology, and a power load and a measurement device therefor are provided.

It is a block diagram in connection with Example 1 of this invention. It is a figure which shows the relationship between the DC voltage of a solar panel, and a power generation output. It is a circuit diagram of a typical solar power generation device. It is a figure which shows the relationship between the direct-current voltage at the time of setting it as an output suppression state, and a power generation output. It is a figure which shows the relationship between a direct current at the time of setting it as an output suppression state, and a direct current voltage. It is a figure which shows the relationship 1 of the electric current at the time of changing solar radiation conditions and panel temperature conditions, and maximum electric power which can be generated. It is a figure which shows the relationship 2 of the electric current at the time of changing solar radiation conditions and panel temperature conditions, and maximum electric power which can be generated. It is a figure which shows the relationship 3 of the electric current at the time of changing solar radiation conditions and panel temperature conditions, and maximum electric power which can be generated. It is a circuit diagram of the solar power generation device 1 of the present invention. It is a figure which shows the relationship between a DC voltage and an output voltage. It is a figure which shows the relationship between a DC voltage and a direct current. It is a figure which shows the calculation procedure of the maximum output possible electric power in Example 1. FIG. FIG. 6 is a configuration diagram related to Example 2. It is a figure which shows the operation | movement method in the state connected with the electric power grid | system in Example 2. FIG. It is a figure which shows the relationship between the DC voltage and power generation output in Example 3. It is a figure which shows the relationship between the DC voltage and DC current in Example 3. It is a figure which shows the operation | movement at the time of switching from the operating point 2 in Example 3 to the operating point 1. FIG. FIG. 10 is a configuration diagram related to Example 3. It is a figure which shows the operation | movement method in the state connected with the electric power grid | system in Example 3. FIG. It is a figure which shows the calculation procedure of the maximum output possible electric power in Example 3. FIG. FIG. 10 is a configuration diagram related to Example 4; FIG. 10 is a configuration diagram related to Example 5; FIG. 10 is a configuration diagram related to Example 6; FIG. 10 is a configuration diagram related to Example 7. It is a figure showing the time change of the supply-and-demand gap in Example 1, and the state of a demand apparatus. FIG. 10 is a configuration diagram related to Example 8. It is an equivalent circuit of a photovoltaic power generation panel. It is a figure which shows the relationship between the DC voltage when the panel temperature changes, and the power generation output. FIG. 10 is a configuration diagram related to Example 9. FIG. 10 is a circuit diagram of a measuring device 13 in Example 9. FIG. 10 is a diagram illustrating a search method for maximum outputable power according to the tenth embodiment. It is a figure which shows the time transition of the operation state of the apparatus in Example 3. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, prior to that, first, the features of the present invention will be summarized and described below.

  According to the present invention, the photovoltaic power generation apparatus has a function of predicting the maximum power that can be generated, and the measured DC current value and the measured DC voltage value at the controlled operating point are used while controlling the operating condition of the solar panel. The maximum power that can be generated is predicted and transmitted to an external device through data communication means. An external device may be a control device for a demand device when installed in a customer facility, a gateway for connecting to a management server via the Internet, or a power company and its own device. It may be a smart meter connected via a network, or may be a monitor screen in a customer facility, or an information device such as a smartphone or a PC. When provided in a power generation facility such as a mega solar, it may be a gateway for communicating with an electric power company.

  In addition, the calculation of the maximum power that can be generated when the output of the solar power generation device in the present invention is suppressed is a direct current value in a state where the solar panel is operated at a voltage lower than a voltage that can obtain the maximum power that can be generated. DC voltage value is measured and calculated using a pre-stored calculation formula or calculation table.

  FIG. 4 is a diagram showing an example of the relationship between the DC voltage and the power generation output when the output is suppressed. It can be seen that there are two operating points that output the suppressed power across the maximum power that can be generated. FIG. 5 is a diagram illustrating an example of a relationship between a direct current and a direct voltage when the output is suppressed.

  Here, FIG. 6 shows an example of the relationship between the short-circuit current (DC voltage 100 V) and the maximum power that can be generated when the solar radiation condition and the panel temperature condition are changed. Although there is an error of about 10%, it can be seen that the maximum power that can be generated is approximately proportional to the short-circuit current. FIG. 7 shows an example of the relationship between the DC current at the DC voltage of 100V and the maximum power that can be generated. FIG. 8 shows an example of the relationship between the DC current at the DC voltage of 150V and the maximum power that can be generated. 6, 7, and 8 are almost the same graphs with only slightly different slopes. For this reason, in the means of the present invention, the voltage at the operating point 1 differs depending on the output power, but after calculating the proportionality coefficient between the current value at that voltage and the maximum output power, the maximum output power from the DC current. Can be predicted.

  Since the proportionality coefficient varies depending on the panel type and installation conditions, it is desirable to operate at an operating point 1 intermittently during normal operation without output suppression, and to store a table of maximum power that can be generated, DC voltage, and DC current. It is better to calculate and store the slope of the maximum power that can be generated by the direct current.

FIG. 27 shows an equivalent circuit of a solar panel. The solar panel is composed of a constant current source for _supplying a current _Iph corresponding to solar radiation, a diode, and wiring resistances R _s and R _sh . The relationship between currents I and V is expressed by the following equation.

Formula 1: I = I _ph -I ₀ (exp (q (V + R _s I) / nkT) -1)-(V + R _s I) / R _sh
Here, “I ₀ ” is the reverse saturation current, “q” is the elementary charge, “n” is the ideal diode factor, “k” is the Boltzmann constant, and “T” is the absolute temperature of the panel. When V is small, the term of _Iph becomes dominant, and it is estimated that the influence of _Iph is large even in the voltage indicating the maximum power that can be generated. Therefore, it is presumed that the current value in a small voltage range is approximately proportional to the maximum power that can be generated.

The error of about 10% between the direct current and the maximum power that can be generated in FIGS. 6, 7, and 8 depends on the term I ₀ (exp (q (V + R _s I) / nkT) -1) in Equation 1. It is considered that the influence of the panel temperature T is large. In the open-circuit voltage in FIG. 5, since I = 0, Expression 1 is expressed as Expression 2.

Formula 2: 0 = I _ph -I ₀ (exp (qV / nkT-1))-V / R _sh
Here, _assuming that R _sh is sufficiently larger than V, it can be calculated as follows.

Formula 3: I _ph = I ₀ (exp (qV / nkT-1)
Formula 4: ln (I _ph / I ₀ +1) = qV / nkT
Therefore, it can be seen from Equation 4 that when I _ph is constant, V and T are in a proportional relationship.

  FIG. 28 shows the relationship between the DC voltage and the power generation output when the solar radiation is constant and the panel temperature changes. From Equation 4, the open circuit voltage is proportional to the panel temperature. From FIG. 28, the error of the maximum power that can be generated is proportional to the open circuit voltage and proportional to the panel temperature. In the voltage range larger than the voltage indicating the maximum power that can be generated, the influence of the panel temperature is considered to be large as in the case of the open circuit voltage. Therefore, the error between the voltage at the operating point 2 and the maximum power that can be generated is considered to be approximately proportional. That is, by correcting using the direct current and direct current voltage at the operating point 2, the relational expression between the direct current and the maximum power that can be generated in FIGS. 6, 7, and 8 can be made more accurate. .

  According to the present invention described above, when power is generated with a power smaller than the maximum power that can be generated in a given environment, an overload state is predicted in advance to adjust the demand. Output stoppage can be prevented.

  In addition, according to the present invention, when predicting the maximum output possible power at the time of output suppression of solar power generation, by using the direct current and direct current voltage output from the solar panel to generate power, Because no additional measurement device such as a solar radiation meter is required, the prediction error of the maximum output possible power prediction value due to the positional deviation of the measurement device and the solar panel and the temperature of the solar panel is reduced, and high accuracy prediction is reduced. Can be realized at a cost.

Further, according to the present invention, it is possible to add a new service or function using information on the maximum power that can be generated.
And according to this invention, the electric power supply-and-demand management of an electric power system finer than the conventional method can be performed using the information of the maximum electric power which can be generated.

  The apparatus structure of the customer system containing the solar power generation device in 1st Embodiment is shown in FIG. In this embodiment, the customer system 100 is not connected to the power system, and performs a self-sustained operation only with the photovoltaic power generated by the solar panel 2. The solar power generation device 1 converts the direct current output of the solar panel 2 into alternating current and outputs it to the distribution board 4. The solar power generation device 1 adjusts the direct current and direct current voltage of the solar panel 2 so that the alternating current output voltage becomes constant. The solar power generation device 1 receives the information request from the control device 3, and sends the maximum power generation possible power information and the current generated power at that time to the control device 3. The control device 3 grasps the supply and demand gap that is the difference between the maximum power that can be generated and the generated power, and when the supply and demand gap becomes smaller, sends a control signal for limiting power to the demand load 5 or the demand load 6, Even if there is a change in the power supply capacity due to changes in the amount of solar radiation, etc., or when the demand changes depending on the usage status of the user, the demand is suppressed by sending a switch open / close control signal to the switchboard 4. Make adjustments so that supply and demand do not exceed supply. When the demand load 5 is an air conditioner, the set temperature is changed or the cooling / heating setting is switched to air blowing. When the demand load 6 is TV, the brightness is reduced.

  FIG. 25 shows the operation status of the demand equipment with respect to the time change of the supply and demand gap. The control device 3 stores the priority for each demand load, and reduces the power of the demand load 7 having a low priority when the supply and demand gap is equal to or less than the set value 1. After that, when the supply and demand gap further decreases and becomes the set value 1 or less again, the power of the demand load 6 having the next lowest priority is reduced. After that, when the supply and demand gap becomes larger and exceeds the set value 2, the power of the demand load 6 having a high priority is restored in the demand load for which power reduction control is performed.

FIG. 9 shows a circuit diagram of the solar power generation device 1 of the present embodiment. The ammeter 20 and the voltmeter 21 measure the direct current and direct current voltage of the solar panel 2. The control block 23 of the photovoltaic power generator 1 performs the PWM control using the switches S2 to S5 so that the output voltage becomes constant, and at the same time controls the switch S1 so that the voltage of the capacitor 22 becomes constant. FIG. 10 shows an example of the relationship between the DC voltage and the output voltage under a certain installation condition and a certain weather condition, and FIG. 11 shows an example of the relationship between the DC voltage and the DC current under the same conditions. There are two combinations of DC voltage and DC current in order to obtain output power below the maximum output possible power. For example, when the power demand is 2000 W, in this embodiment, the switch S1 is controlled so as to operate at the operating point 1 which is a voltage lower than the voltage capable of obtaining the maximum output power.

  FIG. 12 shows a procedure for calculating the maximum output possible power in this embodiment. In the control block 23 in FIG. 9, the relational expression between the maximum output possible power Pmax1 and the direct current at the operating point 1 as shown in FIG. ), V = 50 (V), V = 100 (V), and V = 150 (V) are stored as straight lines passing through “0 (zero)”. Next, since the DC voltage V = 88 (V) when operating at the operating point 1 from FIG. 11, as shown in FIG. 12 (b), the slope 142 of the voltage V = 50 (V) close to this is shown. From the slope 145 of V = 100 (V), the slope of the straight line when V = 88 (V) is proportionally calculated to be 144.3. As shown in FIG. 12 (c), since the direct current I at operation point 1 in FIG. 11 is I = 22.8 (A), if the position on the straight line of V = 88 (V) is specified, the maximum output power can be obtained. A certain Pmax1 = 3290 (W) is obtained. In the calculation procedure in the present embodiment, although an error due to the temperature of the solar panel 2 is included, it can be predicted with an accuracy of about 10%.

  According to this example, when generating power with a power smaller than the maximum power that can be generated, the maximum power that can be generated by the solar panel is compared with the case where an additional measuring device such as a solar cell for monitoring or a solar radiation meter is used. It is possible to calculate with high accuracy, and by adjusting the demand of demand equipment according to the supply and demand gap, which is the difference between the maximum power that can be generated and the generated power, there is a change in power supply capacity due to changes in solar radiation, etc. Even when the demand changes depending on the use situation of the user, the customer system can be controlled so that the supply and demand does not always exceed the supply.

  The apparatus structure of the customer system containing the solar power generation device in 2nd Embodiment is shown in FIG. In the present embodiment, the customer system 100 can switch between a state connected to the power system by the switchgear 8 and an independent operation state not connected to the power system. The solar power generation device 1 converts the direct current output of the solar panel 2 into alternating current and outputs it to the distribution board 4.

  In the state linked to the power system in the present embodiment, the photovoltaic power generation device 1 adjusts the DC current and DC voltage of the solar panel 2 so as to maximize the AC output current in synchronization with the AC voltage waveform of the power system. As shown in FIG. 14, the operating point is intermittently set to a voltage smaller than the maximum output possible power for a short time, and the DC current, the DC voltage, and the previous maximum output possible power are stored. The measurement with the operating point changed is measured once every 10 seconds for about 20 ms. The measured voltages are V = 0 (V), V = 50 (V), V = 100 (V), V Measure while changing 4 points of = 150 (V) each time. However, in this embodiment, the measurement frequency, measurement time, measurement voltage, and number of measurement points are not limited to this combination. For example, once in 20 seconds, with a measurement time of about 10 ms, V = 75 (V ), V = 125 (V), V = 150 (V). Note that when the operating point is set to a voltage smaller than the maximum output power, the output power decreases but only for a short time, so that the influence can be reduced to less than 1% of the generated power.

  An operation method in a self-sustaining operation state that is not linked to the power system in the present embodiment will be described. The solar power generation device 1 adjusts the direct current and direct current voltage of the solar panel 2 so that the independent output voltage becomes constant. The solar power generation device 1 receives the information request from the control device 3, and sends the maximum power generation possible power information and the current generated power at that time to the control device 3. The control device 3 grasps the supply and demand gap that is the difference between the maximum power that can be generated and the generated power, and when the supply and demand gap becomes smaller, sends a control signal for limiting power to the demand load 5 or the demand load 6, Even if there is a change in the power supply capacity due to changes in the amount of solar radiation, etc., or when the demand changes depending on the usage status of the user, the demand is suppressed by sending a switch open / close control signal to the switchboard 4. Make adjustments so that supply and demand do not exceed supply.

  The circuit configuration of the solar power generation device 1 of the present embodiment is the same as that of the first embodiment shown in FIG.

  In the case where the operating characteristics of the solar panel 2 and the external environment such as the amount of solar radiation and the temperature are the same as those of the first embodiment, the operation method in the self-sustaining operation state not linked to the power system in this embodiment is shown in FIGS. This is the same as the operation method of the first embodiment using 11 operation points 1.

  The calculation procedure of the maximum output possible power in the self-sustained operation state not linked to the power system in this embodiment is the same as that in the first embodiment, but the current at the operating point 1 and the maximum power that can be generated are the basis of the calculation. The relational expression with Pmax1 uses a value measured in a state connected to the power system.

  According to the present embodiment, it is possible to reflect the installation condition of the solar panel and the characteristic deterioration after the installation by correcting the parameter for calculating the maximum power that can be generated during the independent operation during the grid operation. Further, according to the present embodiment, the influence of the solar panel temperature that varies depending on the season is corrected every day, so that the maximum power that can be generated can be predicted with higher accuracy than in the first embodiment. Using this example, during independent operation, even if there is a change in power supply capacity due to changes in the amount of solar radiation, etc., or even when the demand changes depending on the usage status of the user, the supply and demand will not always exceed the supply. The customer system can be controlled.

  The apparatus structure of the customer system containing the solar power generation device in 3rd Embodiment is shown in FIG. The device configuration of the present embodiment is almost the same as that of the second embodiment, but a storage battery 9 is connected between the distribution board 4 and the switchgear 8 and charged or discharged in response to an instruction from the control device 3. Can do.

  In the state linked to the power system in the present embodiment, the photovoltaic power generation device 1 adjusts the DC current and DC voltage of the solar panel 2 so as to maximize the AC output current in synchronization with the AC voltage waveform of the power system. As in the second embodiment, as shown in FIG. 14, the operating point is intermittently set to a voltage lower than the maximum output power for a short time, and the direct current, the direct current voltage, and the maximum output just before are adjusted. Memorize possible power. Further, as shown in FIG. 19, the operating point is intermittently set to a voltage higher than the maximum output power for a short time, and the DC current, the DC voltage, and the immediately preceding maximum output power are stored. The measurement with the operating point changed is measured once every 10 seconds for approximately 20 ms. The measured voltage is V = 0 (V), V = 50 when the voltage is less than the maximum output power. (V), V = 100 (V), V = 150 (V), and if it is larger than the maximum output power, I = 0 (A), I = 5 (A), I = 10 ( Measure while changing the total of 8 points of A) and I = 15 (A) each time. However, in this embodiment, the measurement frequency, the measurement time, the measurement voltage, and the number of measurement points are not limited by this combination. For example, once in 20 seconds, with a measurement time of about 10 ms, V = 75 (V ), V = 125 (V), V = 150 (V), I = 7 (A), I = 12 (A), I = 17 (A), or a total of six points. In addition, a voltage larger than a maximum output power and a voltage smaller than the maximum output power may be measured alternately, or may be switched to one after the other. When the operating point is set to a voltage that is smaller or larger than the maximum output power, the output power is reduced but only for a short time, so that the influence can be reduced to less than 1% of the generated power.

  In the present embodiment, the entire operation of the customer system 100 in the self-sustaining operation state not linked to the power system will be described. In the self-sustaining operation state not linked to the power system in the present embodiment, the solar power generation device 1 adjusts the direct current and direct current voltage of the solar panel 2 so that the self-sustained output voltage is constant. When the solar power generation device 1 receives an information request from the control device 3, the solar power generation device 1 sends the maximum power generation possible power information and the current generated power at that time to the control device 3. The storage battery 9 is operated in the discharge mode at night, and the customer system is operated with the stored power. During the day, it works as one of the loads that charge the power from the solar power generation device 1. The control device 3 grasps the supply and demand gap that is the difference between the maximum power that can be generated and the generated power, and when the supply and demand gap becomes smaller, sends a control signal for limiting power to the demand load 5 or the demand load 6, Demand is controlled by sending a switch open / close control signal to the switchboard 4 or stopping the charging of the storage battery 9, and there is a change in power supply capacity due to changes in the amount of solar radiation, etc. Even when demand changes, adjustments are always made so that supply and demand do not exceed supply. When the amount of solar radiation becomes small and the control device 3 determines that the output from the solar power generation device 1 does not satisfy the power demand, the control device 3 stops the solar power generation and simultaneously changes the storage battery 9 from the charge mode to the discharge mode. Switch. Conversely, when it is determined that the amount of solar radiation is large and the output from the solar power generation device 1 satisfies the power demand in a state where the storage battery 9 is discharged, the solar battery is switched to the stop at the same time as the solar battery. Operate power generation and switch power sources instantly.

  A specific operation flow of the devices of the demand system 100 will be described with reference to FIG. In the period A corresponding to the dawn when the sun does not rise, the domestic electric power demand is covered by the discharge of the storage battery. At this time, the demand load 7 having a low priority is in the OFF state. In the period B in which the maximum power that can be generated exceeds the power demand due to the rising sun, the control device 3 stops the storage battery 9 and simultaneously causes the output of the solar power generation device 1 to flow to the distribution board 4. In the period C in which the supply-demand gap between the maximum power that can be generated and the power demand is increased, the demand load 7 having a low priority is turned on. In the period D in which the supply-demand gap is further increased, the storage battery 9 is switched to the charging mode and charged. Thereafter, in a period E in which the supply and demand gap is reduced by clouds or the like, the operation of the storage battery 9 is temporarily stopped. Furthermore, in the period F in which the supply and demand gap is reduced, the demand load 7 having a low priority is turned off. Thereafter, in the period G when the supply-demand gap is recovered due to the movement of the clouds, the demand load 7 is turned ON, and in the period H in which the supply-demand gap is increased, the storage battery 9 is charged again. Thereafter, in the period I when the amount of solar radiation is low and the supply and demand gap is reduced, the storage battery 9 is first stopped, and in the period J when the supply and demand gap is further reduced, the demand load 7 having a low priority is turned off. Thereafter, when the maximum power that can be generated is further reduced, the output of the solar power generation device 1 is turned off and the storage battery 9 is discharged at the same time.

  The circuit configuration of the solar power generation device 1 of the present embodiment is the same as that of the first embodiment shown in FIG.

  An operation method of the photovoltaic power generation apparatus 1 in the self-sustaining operation state not linked to the power system in the present embodiment will be described. FIG. 15 shows the relationship between the DC voltage of the solar panel 2 and the power generation output, and FIG. 16 shows the relationship between the DC voltage and the DC current. There are two combinations of DC voltage and DC current in order to obtain output power below the maximum output possible power. For example, when the power demand is 2000 W, in this embodiment, the DC voltage and the DC current are measured while controlling the switch S1 so as to operate at the operating point 1 which is a voltage lower than the voltage capable of obtaining the maximum output power. Then, once every 10 seconds, the DC voltage and the DC current are measured by operating at the operating point 2 for about 20 ms. However, in this embodiment, the measurement frequency and the measurement time are not limited. For example, the measurement time may be about 10 ms once every 20 seconds. By mainly using the operating point 1, the measurement result at the operating point 1 is stabilized, so that there is an advantage that the calculation result of the maximum operable power is stabilized. This is because in the calculation of the maximum operable power, the measured value at the operating point 1 is more dominant than the measured value at the operating point 2.

  When changing the operating point from the operating point 2 to the operating point 1 or from the operating point 1 to the operating point 2, the previous DC voltage is memorized, and the DC voltage is set as the target operating point immediately after switching. Controls the switch S1 so that the voltage of the capacitor 22 becomes constant while finely adjusting the operating point.

  At this time, as shown in FIG. 17, for example, when switching from the operating point 2 to the operating point 1, the stored output power at the DC voltage at the previous operating point 1 is changed due to fluctuations in the amount of solar radiation. When the necessary power is insufficient, the voltage of the capacitor 22 decreases. To compensate for this, the DC voltage is temporarily moved higher to correct the voltage of the capacitor 22. On the contrary, if the power is larger than the required power due to fluctuations in the amount of solar radiation, the voltage of the capacitor 22 increases. To compensate for this, the DC voltage is temporarily moved to a lower level, and the voltage of the capacitor 22 is decreased. to correct.

  Also, for example, when switching from the operating point 1 to the operating point 2, if the output power at the stored DC voltage at the previous operating point 2 is insufficient for the required power due to variations in the amount of solar radiation, Since the voltage of the capacitor 22 decreases, in order to compensate for this, the DC voltage is temporarily moved to a lower value to correct the voltage of the capacitor 22. On the contrary, when the power is larger than necessary due to fluctuations in the amount of solar radiation, the voltage of the capacitor 22 rises. To compensate for this, the DC voltage is temporarily moved higher to compensate for the voltage of the capacitor 22. Correct.

  The calculation procedure of the maximum output possible power in the self-sustaining operation state not linked to the power system in the present embodiment will be described with reference to FIG. In the control block 23, as shown in FIG. 20 (a), the relational expression between the maximum output possible power Pmax1 and the direct current at the operating point 1 is shown as DC voltage V = 0 (V), V at the operating point 1. = 50 (V), V = 100 (V), and V = 150 (V) are stored for each case. Next, since the DC voltage V = 88 (V) when operating at the operating point 1 from FIG. 16, as shown in FIG. 20B, a voltage V = 50 (V), V = Approximate the relational expression of V = 88 (V) from the straight line of 100 (V). Next, as shown in FIG. 20 (c), the position on the straight line from DC current I = 22.8 (A) to V = 88 (V) at operating point 1 in FIG. A certain Pmax1 = 3300 (W) is obtained. Up to this point, it is the same as the first embodiment and the second embodiment, but the estimated value Pmax1 of the maximum output power by this method includes a calculation error due to the temperature of the solar panel 2 around 10%. Therefore, in order to further improve the accuracy, the calculation is performed using the DC voltage and DC current at the operating point 2. In the control block 23 in FIG. 9, the relational expression between the ratio of the true maximum output power Pmax and Pmax1 and the direct current voltage at the operating point 2 as shown in FIG. ), I = 5 (A), I = 10 (A), and I = 15 (A). Next, from FIG. 16, since the direct current I = 12 (A) at the operating point 2, as shown in FIG. 20 (e), currents I = 10 (A) and I = 15 (A) close to this are obtained. Approximate the straight line with I = 12 (A) from the straight line. Next, as shown in FIG. 20 (f), the position on the straight line from the DC voltage V = 200 (V) to I = 12 (A) during operation is specified, and the true maximum output possible power Pmax and the graph are shown. A ratio 1.02 with Pmax1 = 3300 (W) obtained in 20 (a) to (c) is obtained. Since the true maximum output power Pmax is a product of Pmax1 = 3300 (W) and 1.02, Pmax = 3366 (W).

  According to the present embodiment, the maximum power that can be generated by the solar panel during the self-sustaining operation is obtained by using the data of two points of the operating point 1 and the operating point 2, and the method shown in the first and second embodiments. It is possible to calculate with high accuracy. In addition, according to the present embodiment, the customer system can be stably maintained by adjusting the demand load and the charging power of the storage battery even when the output of the solar panel is unstable due to the influence of clouds or the like during the independent operation. I can do it.

  FIG. 21 shows an apparatus configuration of a customer system including the photovoltaic power generation apparatus according to the fourth embodiment. In addition to the configuration of the third embodiment shown in FIG. 18, there is a display device 11 that displays power information such as the maximum power that can be generated and generated power sent from the control device, and the power supply / demand gap that is the difference between them.

  The operation method in the state linked to the power system in the present embodiment is the same as that in the third embodiment shown in FIGS.

  In this embodiment, the operation method of the customer system 100 in a self-sustained operation state not linked to the power system is basically the same as that of the third embodiment. However, the display device 11 allows the user to generate the maximum power that can be generated and the generated power. Therefore, it is possible to check power information such as the power supply-demand gap that is the difference between them, and by operating the demand equipment according to the supply-demand gap, it becomes possible to use limited power according to needs.

  The circuit configuration of the solar power generation device 1 of the present embodiment is the same as that of the first embodiment shown in FIG.

  An operation method of the photovoltaic power generation apparatus 1 in the self-sustaining operation state not linked to the power system in the present embodiment will be described. When the operating characteristics of the solar panel 2 and the external environment such as solar radiation and temperature are the same as in the third embodiment, the relationship between the DC voltage and the output voltage is the same as that shown in FIG. The relationship of current is the same as that shown in FIG. There are two combinations of DC voltage and DC current in order to obtain output power less than the maximum output possible power. In the third embodiment, the operation is mainly performed at the operating point 1 which is a voltage lower than the voltage capable of obtaining the maximum output power. However, in this embodiment, the DC voltage and the DC current are measured while controlling the switch S1 so as to operate at the operating point 2 that is higher than the voltage at which the maximum output power can be obtained, and once every 10 seconds. The DC voltage and DC current are measured by operating at operating point 1 for about 20 ms. However, in this embodiment, the measurement frequency and the measurement time are not limited. For example, the measurement time may be about 10 ms once every 20 seconds.

  The calculation procedure of the maximum output possible power in the self-sustaining operation state not linked to the power system in the present embodiment is the same as that in the third embodiment shown in FIG.

  According to the present embodiment, by using the operating point 2 mainly, there is an advantage that the direct current can be made smaller than the operation at the operating point 1 and the heat generation of the circuit can be reduced. In addition, according to the present embodiment, the user can operate the demand equipment while confirming the supply and demand gap, which is the difference between the maximum power that can be generated at home and the power demand, by the display device during the independent operation, and thus the amount of solar radiation varies. Even in this case, it is possible to maintain the customer system continuously while meeting the user's needs.

  The apparatus structure of the customer system containing the solar power generation device in 5th Embodiment is shown in FIG. Although the configuration and operation of the present embodiment are almost the same as those of the second embodiment, the demand load 5 and the demand load 6 are not control signals, but information on the power generation surplus that is the difference between the maximum power that can be generated and the generated power is received from the control device 3. be delivered. The demand load 5 and the demand load 6 have a function of voluntarily changing the operation mode based on the generated power generation surplus. For example, the stability of the customer system 100 against a change in power supply and demand is improved by changing the set temperature of the air conditioner when the power generation surplus is small and large. According to the method of the present embodiment, if the room temperature is a level that is harmful to health, the temperature setting is not changed.

  In this embodiment, the power generation surplus information is distributed from the control device 3, but the photovoltaic power generation device 1 sends the power generation surplus information to the network by multicast, and the demand load 5 and the demand load 6 are independent. It may be configured to receive and operate automatically.

  According to the present embodiment, the demand load independently adjusts the electric power according to the power generation surplus and its own state, so that it is possible to reduce the possibility of giving an unreasonable instruction to the demand load side when adjusting the power. .

  FIG. 23 shows an apparatus configuration of a customer system including the solar power generation apparatus according to the sixth embodiment. In this embodiment, the control device 3 of the customer system 100 is connected to the Internet via the router 10 and further connected to the management server 200.

  The management server 200 instructs the control device 3 about the maximum reverse power flow. The control device 3 calculates the reverse power flow power from the generated power of the solar power generation device 1 and the power used obtained from the distribution board 4 so that the solar power is less than the maximum reverse power flow instructed from the management server 200. The power generated by the power generation device 1 is suppressed. Further, the control device 3 transmits to the management server 200 the power generation surplus that is the difference between the maximum power that can be generated from the solar power generation device 1 and the current power generation.

  The operation of the photovoltaic power generation apparatus 1 when power is suppressed and the calculation method of the maximum power that can be generated are in accordance with those shown in the first to fourth embodiments.

  The management server 200 is connected similarly to a plurality of customer systems including the customer system 100, and manages the current power supply and demand in the region. By grasping the power generation surplus from each customer system, when the solar power generation power drops due to a cloud in a part of the same area, the maximum reverse power flow of the customer system without the cloud is calculated. Balance can be achieved by giving large instructions. At this time, accurate power management can be performed by grasping the power generation surplus of each customer system.

  FIG. 24 shows an apparatus configuration of a power generation system including the solar power generation apparatus according to the seventh embodiment. In this embodiment, the gateway 14 of the power generation system 101 is connected to the Internet and further connected to the management server 200.

  The management server 200 instructs the gateway 14 to suppress power. The gateway 14 issues an instruction to suppress the generated power of the solar power generation device 1 so that it is equal to or lower than the power instructed from the management server 200. Further, the gateway 14 transmits the maximum power that can be generated from the photovoltaic power generation apparatus 1 and the current generated power to the management server 200.

  The operation of the solar power generation device 1 and the calculation method of the maximum power that can be generated are in accordance with those shown in the first to fourth embodiments.

  The management server 200 is connected to a plurality of power generation systems including the power generation system 101, and manages the current power supply and demand in the region. By grasping the power generation surplus from each power generation system, when the solar power generation power drops due to clouding in a part of the same area, etc., the instruction to reduce the suppression amount of the power generation system without clouding etc. Can be balanced. At this time, accurate power management can be performed by grasping the maximum power that can be generated by each power generation system.

  The apparatus configuration of the customer system including the photovoltaic power generation apparatus according to the eighth embodiment is shown in FIG. In addition to the configuration of the third embodiment shown in FIG. 18, there is a control screen 12, which displays power information such as the maximum power that can be generated and generated power sent from the control device 3, and simultaneously displays control information from the user. 3 is transmitted. The control screen 12 is equipped with input devices such as a touch panel and buttons.

  When the user inputs control for turning on the demand load 5 from OFF to the control screen 12 while the customer system 100 is operating independently, the control information is sent to the control device 3. The control device 3 stores the power used for each demand device, predicts how much the supply-demand gap will change when it is turned on, and cancels the user's operation when the supply-demand gap falls below a certain level. , The control screen 12 displays the cancellation.

  According to the present embodiment, in the state where the customer system 100 is operating independently, the output of the photovoltaic power generator 1 is suddenly reduced by detecting the overload state caused by the user's operation in advance and canceling the operation. Has the effect of deterring

  The apparatus configuration of the customer system including the photovoltaic power generation apparatus according to the ninth embodiment is shown in FIG. In addition to the configuration of the third embodiment shown in FIG. 18, there is a measuring device 13 that transmits power information such as maximum power that can be generated and generated power to the control device 3 in response to an information request sent from the control device 3. .

  FIG. 30 shows a circuit diagram of the measuring device 13. In a state where the customer system 100 is linked to the power system, the solar power generation device 1 operates with the maximum power that can be generated. At this time, the control block 24 of the measuring device 13 measures the open voltage with the voltmeter 21 in a state where the switch S7 is OFF and the switch S6 is OFF for a short time. Thereafter, the short-circuit current is measured using the ammeter 20 with the switch S7 turned off and the switch S6 turned on. With the switch S7 turned on, the switch S6 is turned on and off intermittently to reduce the direct current flowing through the photovoltaic power generation device 1 to create a state of the operating point 1 in a pseudo manner, and the voltmeter 21 and ammeter 20 DC voltage and DC current may be measured using The control block 24 acquires data corresponding to FIG. 20A from these measured values.

  In the self-sustaining operation state where the customer system 100 is not connected to the power system, the solar power generation device 1 operates at the operating point 2 that is a voltage higher than the maximum power that can be generated. At this time, the control block 24 of the measuring device 13 measures the open voltage with the voltmeter 21 in a state where the switch S7 is OFF and the switch S6 is OFF for a short time. Thereafter, the short-circuit current is measured using the ammeter 20 with the switch S7 turned off and the switch S6 turned on. Instead of measuring the short-circuit current, the switch S7 is turned on and the switch S6 is turned on and off intermittently to reduce the direct current flowing to the photovoltaic power generation device 1 to create the state of the operating point 1 in a pseudo manner. A method of measuring DC voltage and DC current using the voltmeter 21 and the ammeter 20 may be used. Thereafter, the maximum output possible power is calculated by the method shown in FIG. 20 and transmitted to the control device 1.

  According to the present embodiment, when only the measuring device 13 is added to the conventional solar power generation device 1 and the power is generated with power smaller than the maximum power generation possible, the maximum power generation possible of the solar panel is accurately calculated. By adjusting the demand of demand equipment according to the gap between supply and demand, which is the difference between the maximum power that can be generated and the generated power, there is a change in power supply capacity due to changes in solar radiation, etc. Even when the demand changes depending on the usage status, the customer system can always be controlled so that the supply and demand does not exceed the supply.

  The apparatus configuration of the customer system including the photovoltaic power generation apparatus according to the tenth embodiment is the same as that of Example 3 shown in FIG. Moreover, the circuit diagram of the solar power generation device 1 is the same as that according to the first embodiment shown in FIG.

  In the self-sustaining operation state where the customer system 100 is not linked to the power system, the solar power generation device 1 operates at the operating point 1 as shown in FIG. 31, but intermittently searches for the maximum power that can be generated for a short time. In addition, the direct current and direct current voltage of the solar panel 2 are adjusted. Since the output increases during the search, the voltage of the capacitor 22 may rise. For example, if the time is about 10 ms once every 10 seconds, the search can be made with little influence.

  According to the present embodiment, when generating power with a power smaller than the maximum power that can be generated, it is possible to accurately calculate the maximum power that can be generated by the solar panel, which is the difference between the maximum power that can be generated and the generated power. By adjusting the demand of demand equipment according to the supply and demand gap, supply and demand will always be supplied even when there is a change in power supply capacity due to changes in the amount of solar radiation and when the demand changes depending on the user's usage conditions. The customer system can be controlled so as not to exceed.

  DESCRIPTION OF SYMBOLS 1 ... Solar power generation device, 2 ... Solar power panel, 3 ... Control apparatus, 4 ... Distribution board, 5-7 ... Demand load, 8 ... Switchgear, 9 ... Storage battery, 10 ... Router, 11 ... Display apparatus, 12 ... control screen, 13 ... measuring device, 14 ... gateway, 20 ... ammeter, 21 ... voltage system, 22 ... capacitor, 23 ... control block, 24 ... control block, 100, 102, 103 ... consumer system, 101 ... power generation System, 200 ... management server, S1-S7 ... switch element

Claims (16)

A solar power generation device having a means for generating power with a power smaller than the maximum power that can be generated in a given environment, and a data communication means,
Control means for controlling the direct current voltage or direct current of the solar panel;
Measuring means for measuring the DC voltage and the DC current;
The control means uses the DC current and the DC voltage obtained by the measurement means when operated at a voltage lower than the voltage at which the maximum power that can be generated by the solar panel is obtained in the environment, A solar power generation device having a function of calculating the maximum power that can be generated in the environment without requiring solar radiation data and transmitting the calculated predicted value of the maximum power that can be generated through the data communication means . In the solar power generation device according to claim 1,
When the solar panel is operated at a power lower than the maximum power that can be generated in the environment, the solar panel is operated at a voltage lower than a voltage that can obtain the maximum power that can be generated by the solar panel in the environment. A solar power generation device. In the solar power generation device according to claim 1,
Having a self-sustaining operation state in which the solar panel is operated with power lower than the maximum power that can be generated and a power system linkage state that generates power with the maximum power that can be generated in the environment,
In the power system cooperation state, the photovoltaic power generation apparatus is characterized by intermittently operating with power lower than the maximum power that can be generated and measuring the DC current, the DC voltage, and the immediately preceding maximum power that can be generated. In the solar power generation device according to claim 1,
In addition to the DC current and the DC voltage when operated at the low voltage,
A solar power generation device that calculates the maximum power that can be generated in the environment using the DC current and the DC voltage when operated at a voltage higher than a voltage that can obtain the maximum power that can be generated. . In the solar power generation device according to claim 4,
It is operated at the maximum power possible power voltage lower than the voltage obtained by the solar panel before Symbol environment, intermittently the operated at a voltage higher than the maximum generated electric power voltage obtained by the direct current and A photovoltaic power generation apparatus that measures the DC voltage and the immediately preceding maximum power that can be generated. In the solar power generation device according to claim 4,
The prior Symbol environment solar panels to operate at a higher voltage than the voltage obtained by maximum generated power of the power, intermittently the maximum generated electric power is operated at a lower voltage than the voltage obtained by the direct current and A photovoltaic power generation apparatus that measures the DC voltage and the immediately preceding maximum power that can be generated. In the solar power generation device according to claim 5 or 6,
Immediately after switching the low voltage and the high voltage from one to the other, if the generated power immediately after switching is higher than the generated power immediately before switching, temporarily generate power with lower power than the generated power immediately after switching, When the generated power immediately after the switching is lower than the generated power immediately before the switching, the solar power generation device is characterized in that the power generation is temporarily performed with a higher power than the generated power immediately after the switching. The solar power generation device according to claim 1, further comprising:
Means for controlling the DC voltage or DC current of the solar panel;
Means for measuring the DC voltage and the DC current;
When operating the solar panels at a power lower than the maximum generated electric power under the environmental, intermittently changing the DC current and DC voltage, a voltage obtained a maximum generated electric power of the solar panel A solar power generation device characterized by searching. A solar power generation device according to claim 1;
A power management system having a screen display means,
A power management system that displays the maximum power that can be generated from the solar power generation device or a numerical value that is processed based on the maximum power that can be generated on a screen. A solar power generation device according to claim 1;
Means for measuring the total power used by a plurality of power loads connected to the solar power generation device;
A power management system having a control device that changes an operating state of the power load,
Based on the difference between the maximum power that can be generated or the maximum power that can be generated obtained from the photovoltaic power generation apparatus and the total power that is currently used, the operating state of the power load is changed, Power management system. The power management system of claim 10, further comprising:
Means for setting a priority for each of a plurality of power loads controlled simultaneously, or means for storing individual power for each operating state for each power load;
When the difference between the maximum power that can be generated and the total of the currently used power is reduced, the operating state of the power load is changed based on the priority order or the individual power or both. A power management system characterized by reducing the total power. The power management system of claim 10, further comprising:
Means for storing individual power for each operating state for each of a plurality of power loads controlled simultaneously;
When it is desired to change the operation state of an arbitrary power load, the difference between the predicted power consumption values before and after the change of the operation state of the selected power load, and the maximum power that can be generated and the total of the currently used power A power management system characterized by comparing the difference and selecting whether or not the operating state can be changed in advance. A solar power generation device according to claim 1;
Means for measuring the total power used by a plurality of power loads connected to the solar power generation device;
A power management system having a control device for changing an operating state of the power load,
A power management system that notifies the power load of a difference between the maximum power that can be generated obtained from the solar power generation device and a total of the power that is currently used. A solar power generation device according to claim 1;
A power management system having external communication means to a management server that manages a plurality of the photovoltaic power generation devices,
A power management system that transmits the maximum power that can be generated from the solar power generation device or a numerical value that is processed based on the maximum power that can be generated to the management server through the external communication unit. The power management system according to claim 14, wherein
In accordance with an instruction from the management server , the power management system increases or decreases the power generation amount of the solar power generation device . A measuring device that measures the maximum power that can be generated in the environment of a solar power generation apparatus having a means for generating power with a power smaller than the maximum power that can be generated in a given environment of a solar panel,
Control means for controlling the direct current voltage or direct current of the solar panel;
Measuring means for measuring the direct current and direct current voltage of the solar panel;
The control means uses the DC current and the DC voltage obtained by the measurement means when operated at a voltage lower than the voltage at which the maximum power that can be generated by the solar panel is obtained in the environment, A measuring apparatus that calculates the maximum power that can be generated in the environment without requiring solar radiation data.

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