# US 2013/0155739 A1 · Solar power generation system, control device used for solar power generation system, and control method and program for same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0155739 A1 - Document ID: US20130155739A1 - Status: Published application - Kind: A1 - Application number: 13/819,613 - Filed: 2011-08-26 - Published: 2013-06-20 - Earliest claimed: 2010-08-27 - Assignees: School Judicial Person Ikutokugakuen - Inventors: Kazutaka Itako - Web page: https://patentgrep.com/patent/US20130155739A1 ## CPC - H02S 10/00: PV power plants; Combinations of PV energy systems with other systems for the generation of electric power - G05B 15/02: electric - G05F 1/67: to the maximum power available from a generator, e.g. from solar cell - G05F 3/08: wherein the variable is DC - G05F 5/00: Systems for regulating electric variables by detecting deviations in the electric input to the system and thereby controlling a device within the system to obtain a regulated output - H02M 7/44: by static converters - Y02E 10/56: Power conversion systems, e.g. maximum power point trackers - Y10S 323/906: Solar cell systems - H02S: GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES (obtaining electrical energy from radioactive sources G21H1/12; light sensitive inorganic semiconductor devices H10F; light sensitive organic semiconductor devices H10K30/00; thermoelectric devices H10N10/00; pyroelectric devices H10N15/00) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) - G05F: SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract In a light power generation system, a control device, a control method, and a program, efficient power can be supplied. The maximum power detection unit operates a MOSFET in a power converter circuit and open-circuits both ends of a solar cell panel in the maximum power detection mode. After that, the maximum power detection unit short-circuits both ends of the solar cell panel, detects a maximum power by monitoring the output power of the solar cell panel during a period from the open state to the short-circuited state, and defines the voltage of the solar cell panel as an optimal voltage when detecting the maximum power. In a tracking operation mode, the control unit performs PWM control with respect to the MOSFET by defining the optimal voltage to be a reference signal. Operations are repeated between the maximum power detection mode and the tracking operation mode. ## Claims ### Claim 1 A light power generation system comprising: a light power generation unit for generating power in response to incident light; a voltage detecting means for detecting an output voltage of the light power generation unit; a current detecting means for detecting an output current of the light power generation unit or a power detecting means for detecting an output power of the light power generation unit; a power converting means including a switching element, converting the output voltage of the light power generation unit in response to an on/off operation of the switching element, and outputting the power of the voltage; and a controlling means for alternately performing a control operation of a maximum power detection mode and a control operation of a tracking operation mode; and controlling the switching element in the two modes to control the conversion operation of the power converting means, wherein the controlling means, in the maximum power detection mode, makes the switching element in the power converting means operate to a first logic state to open the circuit between the output terminals of the light power generation unit and makes the switching element operate to a second logic state from the open-circuit state to short-circuit the output terminals of the light power generation unit and, in the process, detects the point at which the power of the product of the voltage which was detected by the voltage detecting means and the current which was detected by the current detecting means or the power which was detected by the power detecting means becomes the maximum and detects the voltage which was detected by the voltage detecting means at the time when detecting the maximum power as the optimal output voltage, and wherein, the controlling means, in the tracking operation mode, makes the switching element operate so that a difference between the reference voltage and the voltage which was detected by the voltage detecting means becomes “0” or almost “0” using the optimal output voltage as the reference voltage. ### Claim 2 (depends on 1) The light power generation system as set forth in claim 1, wherein the power converting means includes a DC-DC converter which includes the switching element which was provided so as to open/close the output terminals of the light power generation unit. ### Claim 3 (depends on 1) The light power generation system as set forth in claim 1, wherein the power converting means includes an inverter which includes the switching element which was provided so as to open/close the output terminals of the light power generation unit. ### Claim 4 (depends on 1) The light power generation system as set forth in claim 1, wherein: the power converting means includes a DC-DC converter which operates so as to maintain a voltage between the output terminals of the light power generation unit constant and an inverter which includes the switching element which is provided in the latter stage of the DC-DC converter and is controlled in accordance with the load, and the controlling means has a first controlling means for controlling the DC-DC converter and a second controlling means for controlling the inverter. ### Claim 5 (depends on 1) The light power generation system as set forth in claim 1, which corrects an operation point of a hill-climbing method by using the optimal output voltage detected in the maximum power detection mode. ### Claim 6 A control device which is applied to a light power generation control system which has a light power generation unit which generates power in accordance with incident light, a voltage detecting means for detecting a terminal voltage of the light power generation unit, a current detecting means for detecting an output current of the light power generation unit or a power detecting means for detecting an output power of the light power generation unit, and a power converting means which includes a switching element, converts the output voltage of the light power generation unit in accordance with the ON/OFF operation of the switching element, and outputs power of that voltage, wherein the control device is a control device which alternately performs a control operation in a maximum power detection mode and a control operation in a tracking operation mode, controls the switching element in the two modes, and controls the conversion operation of the power converting means, and the control device, in the maximum power detection mode, makes the switching element in the power converting means operate to the first logic state to open the circuit between the output terminals of the light power generation unit and makes the switching element operate from the open-circuit state to the second logic state to short-circuit the output terminals of the light power generation unit and, in that process, detects the point at which the power of the product of the voltage which was detected by the voltage detecting means and the current which was detected by the current detecting means or the power which was detected by the power detecting means becomes the maximum and detects the voltage which was detected by the voltage detecting means at the time when detecting the maximum power as the optimal output voltage, and in the tracking operation mode, uses the optimal output voltage as the reference voltage and makes the switching element operate so that the difference between the reference voltage and the voltage detected by the voltage detecting means becomes “0”or almost “0”. ### Claim 7 (depends on 6) The control device as set forth in claim 6, wherein: the control device has a maximum power detecting means for operating in the maximum power detection mode, monitoring the power of the product of the voltage which was detected by the voltage detecting means and the current which was detected by the current detecting means or the power which was detected by the power detecting means, detecting the maximum power, and detecting the optimal voltage corresponding to the detected maximum power, a holding means for holding the detected optimal voltage, a reference signal generating means for operating in the maximum power detection mode and generating a first reference signal for making the switching element in the power converting means operate to the first logic state for a period from the start point of the maximum power detection mode to when opening the circuit between the output terminals of the light power generation unit and a second reference signal from the output terminal of the light power generation unit which falls by a predetermined rate at the time of the open-circuit state for a period from the open-circuit state to when short-circuiting the output terminals of the light power generation unit, a first controlled operating means for generating a control signal in accordance with a difference between the first and second reference signals which are output from the reference signal generating means and the voltage which was detected by the voltage detecting means in the maximum power detection mode, a second controlled operating means for generating a control signal in accordance with a difference between the optimal voltage which is held in the holding means and the voltage which was detected by the voltage detecting means in the tracking operation mode, a signal selecting means for selecting and outputting the output signal of the first controlled operating means in the maximum power detection mode and selecting and outputting the output signal of the second controlled operating means in the tracking operation mode, a control signal generating means for generating a control signal for controlling the drive of the switching element of the power converting means in accordance with the output signal of the signal selecting means, and a mode controlling means for switching between the maximum power detection mode and the tracking operation mode. ### Claim 8 (depends on 7) The control device as set forth in claim 7, wherein: the power converting means includes a DC-DC converter which includes the switching element which is provided so as to open/close the output terminals of the light power generation unit, and the control device controls drive of the switching element in the DC-DC converter. ### Claim 9 (depends on 8) The control device as set forth in claim 8, wherein: the power converting means includes a DC-DC converter which is controlled so as to maintain the voltage between the output terminals of the light power generation unit constant, and an inverter which includes the switching element which is provided in the latter stage of the DC-DC converter and is controlled in accordance with the load, and the controlling means performs first control processing of controlling the DC-DC converter, and second control processing of controlling the inverter. ### Claim 10 (depends on 6) The control device as set forth in claim 6, wherein the control signal generating means generates a control signal for controlling by PWM the switching element of the power converting means in accordance with the output signal of the signal selecting means. ### Claim 11 (depends on 6) The control device as set forth in claim 6, which corrects an operation point of a hill-climbing method by using the optimal output voltage detected in the maximum power detection mode. ### Claim 12 A control method which is applied to a light power generation system which has a light power generation unit which generates power in accordance with incident light, a voltage detecting means for detecting a terminal voltage of the light power generation unit, a current detecting means for detecting an output current of the light power generation unit or a power detecting means for detecting an output power of the light power generation unit, and a power converting means including a switching element and converting the output voltage of the light power generation unit in accordance with an ON/OFF operation of the switching element and outputting power of that voltage, wherein the control method is a control method for alternately performing a control operation in a maximum power detection mode and a control operation in a tracking operation mode, controlling the switching element in the two modes, and controlling the conversion operation of the power converting means, and comprises steps of, in the maximum power detection mode, making the switching element in the power converting means operate to a first logic state to open the circuit between the output terminals of the light power generation unit and making the switching element operate from the open-circuit state to a second logic state to short-circuit the output terminals of the light power generation unit and, in that process, detecting the point at which the power of the product of the voltage which was detected by the voltage detecting means and the current which was detected by the current detecting means or the power which was detected by the power detecting means becomes the maximum and detecting the voltage which was detected by the voltage detecting means at the time when detecting the maximum power as the optimal output voltage, and in the tracking operation mode, using the optimal output voltage as the reference voltage and making the switching element operate so that a difference between the reference voltage and the voltage which was detected by the voltage detecting means becomes “0” or almost “0”. ### Claim 13 (depends on 12) The control method as set forth in claim 12, which corrects an operation point of a hill-climbing method by using the optimal output voltage which was detected in the maximum power detection mode. ### Claim 14 A program for making a computer run processing for controlling a light power generation system which has a light power generation unit which generates power in accordance with incident light, a voltage detecting means for detecting a terminal voltage of the light power generation unit, a current detecting means for detecting an output current of the light power generation unit or a power detecting means for detecting an output power of the light power generation unit, and a power converting means including a switching element and converting an output voltage of the light power generation unit in accordance with the ON/OFF operation of the switching element and outputting power of that voltage, wherein the program is a program having a routine of alternately performing a control operation in a maximum power detection mode and a control operation in a tracking operation mode, controlling the switching element in the two modes, and controlling the conversion operation of the power converting means, and makes the computer run a first routine of making the switching element in the power converting means operate to a first logic state to open a circuit between the output terminals of the light power generation unit in the maximum power detection mode, a second routine of making the switching element operate from the open-circuit state to a second logic state to short-circuit the output terminals of the light power generation unit and, in that process, detecting the point at which the power of the product of the voltage which was detected by the voltage detecting means and the current which was detected by the current detecting means or the power which was detected by the power detecting means becomes the maximum and detecting the voltage which was detected by the voltage detecting means at the time when detecting the maximum power as the optimal output voltage, a third routine of switching the operation from the maximum power detection mode to the tracking operation mode, and a fourth routine of using the optimal output voltage as the reference voltage and making the switching element operate so that the difference between the reference voltage and the voltage detected by the voltage detecting means becomes “0” or almost “0” in the tracking operation mode. ### Claim 15 (depends on 1) A light power generation unit which includes a photovoltaic power generation unit which generates power in accordance with incident light in claim 1.