Method of and apparatus for enabling output power of solar panel to be maximized

Claim 3

The method of claim 1 wherein the slope is indicated by incrementally changing the load on the panel, and indicating whether the change in value of the monitored parameter in response to the incremental load change is above or below a reference value.

Claim 4

The method of claim 2 wherein the reference value is indicative of the d.c. value of one of said parameters.

Claim 5

The method of claim 3 wherein the reference value is derived by monitoring the approximate d.c. value of the monitored parameter.

Claim 6

The method of claim 1 or 2 or 3 or 4 wherein the monitored parameter is voltage.

Claim 7

The method of claim 1 wherein the slope is indicated by incrementally changing the load on the panel, monitoring one of the parameters of the panel to derive an indication of a reference value, and indicating whether the change in value of the monitored parameter in response to the incremental load change is above or below the reference value.

Claim 10

The method of claim 7 further including indicating whether the change in value of the monitored parameter in response to the incremental load change is above or below a reference value.

Claim 13

The method of claim 9 wherein the reference value is derived by monitoring the approximate d.c. value of the monitored parameter.

Claim 14

The method of claim 10 or 9 wherein the monitored parameter is voltage.

Claim 15

Apparatus for controlling the d.c. output power derived from a photovoltaic solar panel and the power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means responsive to one of the parameters derived from the panel for deriving a signal having a value indicating whether the absolute value of the slope of the voltage versus current curve of the panel is greater or less than unity, the slope indicating means including: means for incrementally changing the load on the panel and means responsive to the incremental load change for comparing the amplitude of the resulting change of the panel monitored parameter with a reference value to indicate whether the slope absolute value is greater or less than one; means responsive to the signal value indicating the slope absolute value being greater than one and less than one for adjusting the load to respectively decrease and increase the current supplied by the panel to the load.

Claim 16

Apparatus for controlling the d.c. output power derived from a photovoltaic solar panel and the power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means responsive to one of the parameters derived from the panel for deriving a signal having a value indicating whether the absolute value of the slope of the voltage versus current curve of the panel is greater or less than unity, the slope indicating means including: means for incrementally changing the load on the panel and means responsive to the incremental load change for comparing the amplitude of the resulting change of the panel monitored parameter with a reference value to indicate whether the slope absolute value is greater or less than one; means responsive to the signal value indicating the slope absolute value being greater than one and less than one for adjusting the load to respectively decrease and increase the current supplied by the panel to the load.

Claim 17

The apparatus of claim 12 wherein the reference value is indicative of the d.c. value of one of said parameters.

Claim 18

The apparatus of claim 13 wherein the reference value is derived by means for monitoring the approximate d.c. value of the monitored parameters.

Claim 19

The apparatus of claim 14 wherein the d.c. value monitoring means includes means responsive to the d.c. output voltage of the panel, and means for attenuating virtually all variations in the d.c. panel output voltage as a result of the load change.

Claim 20

The apparatus of claim 12 or 13 or 14 wherein the monitored parameter is voltage.

Claim 21

The apparatus of claim 12 wherein the means for deriving a signal indicating the slope value includes means for incrementally changing the load on the panel, means for monitoring one of the parameters of the panel to derive an indication of a reference value, and means responsive to the incremental load change for comparing the amplitude of the resulting change of the panel monitored parameter with the reference value to indicate whether the slope absolute value is greater or less than one.

Claim 22

Apparatus for indicating whether the current derived from a photovoltaic solar panel should be increased or decreased in order to maximize the output power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means for incrementally changing the load on the panel, whereby a change in the panel output voltage results from the change in load, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means responsive only to the voltage change resulting from the incremental load change for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value.

Claim 23

Apparatus for indicating whether the current derived from a photovoltaic solar panel should be increased or decreased in order to maximize the output power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means for incrementally changing the load on the panel, whereby a change in the panel output voltage results from the change in load, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means responsive only to the voltage change resulting from the incremental load change for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value.

Claim 24

Apparatus for indicating whether the current derived from a photovoltaic solar panel should be increased or decreased in order to maximize the output power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means for incrementally changing the load on the panel, whereby a change in the panel output voltage results from the change in load, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value, means responsive to the incremental load change for comparing the amplitude of the resulting change of the panel voltage with a reference value to indicate whether the slope absolute value is greater or less than one.

Claim 25

Apparatus for indicating whether the current derived from a photovoltaic solar panel should be increased or decreased in order to maximize the output power supplied by the panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising means for incrementally changing the load on the panel, whereby a change in the panel output voltage results from the change in load, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value, means responsive to the incremental load change for comparing the amplitude of the resulting change of the panel voltage with a reference value to indicate whether the slope absolute value is greater or less than one.

Claim 26

The apparatus of claim 19 wherein the reference value is indicative of the d.c. value of one of said parameters.

Claim 27

The apparatus of claim 20 wherein the reference value is derived by means for monitoring the approximate d.c. value of the monitored parameter.

Claim 28

The apparatus of claim 19 wherein the d.c. value monitoring means includes means responsive to the d.c. output voltage of the panel, and means for attenuating virtually all variations in the d.c. panel output voltage as a result of the load change.

Claim 29

The apparatus of claim 21 wherein the monitored parameter is voltage.

Claim 30

The apparatus of claim 19 wherein the means for indicating includes means for monitoring one of the parameters of the panel to derive the reference value.

Claim 31

Apparatus for maximizing the power supplied by a photovoltaic solar panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising an inverter connected between the panel and load for chopping the d.c. output of the panel into a pseudo-sinusoidal waveform, said inverter supplying increasing current and power from the panel to the load as the chopping frequency thereof increases, means responsive to one of the output parameters of the panel for controlling the frequency of the inverter so that the current and voltage derived by the panel are at the maximum power point for the solar energy incident on and the temperature of the panel, wherein the frequency controlling means includes means for sensing the slope of the curve, and means responsive to the sensed slope for controlling the frequency.

Claim 32

Apparatus for maximizing the power supplied by a photovoltaic solar panel to a load, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, comprising an inverter connected between the panel and load for chopping the d.c. output of the panel into a pseudo-sinusoidal waveform, said inverter supplying increasing current and power from the panel to the load as the chopping frequency thereof increases, means responsive to one of the output parameters of the panel for controlling the frequency of the inverter so that the current and voltage derived by the panel are at the maximum power point for the solar energy incident on and the temperature of the panel, wherein the frequency controlling means includes means for sensing the slope of the curve, and means responsive to the sensed slope for controlling the frequency.

Claim 33

The apparatus of claim 25 wherein the slope sensing means includes means for incrementally changing the load on the panel whereby a change in the panel output voltage results from the change in the inverter frequency, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value.

Claim 34

The apparatus of claim 26 wherein the reference value is indicative of the d.c. output voltage of said panel.

Claim 35

The apparatus of claim 27 wherein the reference value is derived by means for monitoring the approximate d.c. output voltage of the panel.

Claim 36

The apparatus of claim 26 wherein the d.c. value monitoring means includes means responsive to the d.c. output voltage of the panel, and means for attenuating virtually all variations in the d.c. panel output voltage as a result of the load change.

Claim 37

The apparatus of claim 26 wherein the reference value is indicative of an output parameter of the panel.

Claim 38

The apparatus of claim 18, 20, 21, 22, 26, 27, 28 or 29 wherein the means for incrementally loading includes a resistive impedance in shunt with the panel, and means for incrementally changing the impedance from time to time.

Claim 41

In combination, a photovoltaic solar panel, an a.c. load of the type wherein power delivered to it increases as frequency delivered to it increases, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, an inverter connected between the panel and load for chopping the d.c. output of the panel into a pseudo-sinusoidal waveform, said inverter supplying increasing current and power from the panel to the load as the chopping frequency thereof increases, means responsive to one of the output parameters of the panel for controlling the frequency of the inverter so that the current and voltage derived by the panel are at the maximum power point for the solar energy incident on and the temperture of the panel, wherein the frequency controlling means includes means for sensing the slope of the curve, and means responsive to the sensed slope for controlling the frequency.

Claim 42

In combination, a photovoltaic solar panel, an a.c. load of the type wherein power delivered to it increases as frequency delivered to it increases, the panel having a family of curves for voltage versus current output parameters of the panel, the open circuit voltage of each curve in the family increasing as the level of incident solar energy on the panel increases for a predetermined temperature, said curves having a maximum power point, the curves having slopes with absolute values greater than one and less than one for currents respectively greater than and less than the maximum power point, an inverter connected between the panel and load for chopping the d.c. output of the panel into a pseudo-sinusoidal waveform, said inverter supplying increasing current and power from the panel to the load as the chopping frequency thereof increases, means responsive to one of the output parameters of the panel for controlling the frequency of the inverter so that the current and voltage derived by the panel are at the maximum power point for the solar energy incident on and the temperture of the panel, wherein the frequency controlling means includes means for sensing the slope of the curve, and means responsive to the sensed slope for controlling the frequency.

Claim 43

The combination of claim 33 wherein the slope sensing means includes means for incrementally changing the load on the panel whereby a change in the panel output voltage results from the change in the inverter frequency, the magnitude of the voltage change being dependent on the slope of the curve for the incident radiation and temperature and the load change, and means for indicating whether the change in the panel voltage resulting from the incremental load change is above or below a reference value.

Claim 44

The combination of claim 34 wherein the reference value is indicative of the d.c. output voltage of said panel.

Claim 45

The combination of claim 34 wherein the reference value is derived by means for monitoring the approximate d.c. output voltage of the panel.

Claim 46

The combination of claim 36 wherein the d.c. value monitoring means includes means responsive to the d.c. output voltage of the panel, and means for attenuating virtually all variations in the d.c. panel output voltage as a result of the load change.

Claim 47

The combination of claim 34 wherein the reference value is indicative of an output parameter of the panel.

Claim 50

The method of claim 39 wherein the slope is indicated by indicating whether the change in value of the monitored parameter in response to the incremental load change is above or below a reference value.

Claim 51

The method of claim 39 or 40 wherein the load is incrementally changed from time to time by changing the value of a resistive impedance shunting the panel.

Claim 52

The apparatus of claim 23 wherein the means for incrementally loading includes a resistive impedance in shunt with the panel, and means for incrementally changing the impedance from time to time.