Hydro-power generation for irrigation control
Some embodiments provide hydro-power generation systems for irrigation systems. In some embodiments, a system comprises a generator comprising a turbine at least partially inserted into a fluid flow path of a conduit of the irrigation system and to be activated by a fluid flow in the conduit, wherein the generator is to output an electrical power signal; a control circuit to: determine a characteristic of the electrical power signal; determine, based on the characteristic, a load impedance selected from a plurality of load impedances; and output a control signal to select the load impedance. The system also comprises a variable load circuit to: receive the control signal; and provide the load impedance, where an impedance of the variable load circuit is based on the characteristic to provide power generation over various flow rates of fluid in the fluid flow path.
1. A hydro-power generation system for an irrigation system comprising:
a generator comprising a turbine at least partially inserted into a fluid flow path of a conduit of the irrigation system and configured to be activated by a fluid flow in the conduit, wherein the generator is configured to output an electrical power signal in response to the activation of the turbine;
a control circuit coupled to the generator, wherein the control circuit is configured to:
determine a characteristic of the electrical power signal;
determine, based on the characteristic, a load impedance selected from a plurality of load impedances; and
output a control signal to select the load impedance; and
a variable load circuit coupled to the control circuit and configured to:
receive the control signal; and
provide the load impedance based on the control signal;
wherein an impedance of the variable load circuit is based on the characteristic to provide power generation over various flow rates of fluid in the fluid flow path of the conduit of the irrigation system wherein the variable load circuit comprises:
a load having a nominal load impedance;
a switch coupled to the control circuit; and
a supplemental load comprising one or more additional loads coupled to the switch, wherein the control signal controls the switch to selectively couple and decouple at least one of the one or more additional loads to provide the load impedance selected from the plurality of load impedances.
2. The hydro-power generation system of claim 1 , wherein the characteristic comprises a frequency of the electrical power signal.
3. The hydro-power generation system of claim 2 , wherein the control circuit is configured to determine the frequency of the electrical power signal as a function of a timing of pulses of the electrical power signal.
4. The hydro-power generation system of claim 2 , wherein the frequency of the electrical power signal corresponds to one or both of a speed of the turbine and a flow rate of the fluid flow at the turbine.
5. The hydro-power generation system of claim 1 , wherein a value of at least one of the plurality of load impedances varies over time.
6. The hydro-power generation system of claim 1 , wherein a value of at least one of the plurality of load impedances is substantially constant.
7. The hydro-power generation system of claim 1 , wherein the one or more additional loads comprises one or more resistors coupled in series with the load.
8. The hydro-power generation system of claim 1 , wherein the switch comprises a separate switch coupled to the control circuit for each of the one or more additional loads.
9. The hydro-power generation system of claim 1 ,
wherein the control circuit outputs the control signal to selectively control a duty cycle of the switch switching between a closed state and an open state that controls the selective coupling and decoupling of the load to the generator to provide the load impedance selected from the plurality of load impedances.
10. The hydro-power generation system of claim 9 , wherein the switch comprises a transistor.
11. The hydro-power generation system of claim 1 , wherein the variable load circuit comprises:
a rectifier circuit coupled to the generator to convert the electrical power signal to a direct current electrical power signal to be applied to a load, wherein the rectifier circuit comprises a switch coupled in series in a path of the rectifier circuit;
wherein the control circuit outputs the control signal to selectively control a duty cycle of the switch switching between a closed state and an open state that controls the selective coupling and decoupling of current from the path of the rectifier circuit to provide the load impedance selected from the plurality of load impedances.
12. The hydro-power generation system of claim 11 , the rectifier circuit comprises a diode bridge rectifier include a positive diode path and a negative diode path, wherein the switch is coupled in series with one of the positive diode path and the negative diode path.
13. The hydro-power generation system of claim 11 , wherein the switch comprises a transistor.
14. The hydro-power generation system of claim 1 , further comprising a rectifier circuit coupled to the generator to convert the electrical power signal to a direct current electrical power signal to be applied to a load.
15. The hydro-power generation system of claim 1 , wherein the load comprises an energy harvesting circuit.
16. The hydro-power generation system of claim 1 , wherein the load comprises a charging circuit for a power storage device.
17. The hydro-power generation system of claim 1 , further comprising:
a power storage device coupled with the generator and configured to receive the electrical power signal and store electrical energy based on the electrical power signal.
18. The hydro-power generation system of claim 17 , further comprising:
an irrigation device coupled to a power storage device and configured to receive operational power from the power storage device.
19. The hydro-power generation system of claim 18 , wherein the irrigation device comprises one or more of: an irrigation controller, a solenoid, an actuator, and a sensor.
20. The hydro-power generation system of claim 18 , further comprising:
a wireless transceiver irrigation control device coupled to power storage device and configured to receive operational power from the power storage device.
21. A method of hydro-power generation for an irrigation system comprising:
activating, through a fluid flow in a conduit of an irrigation system, a turbine of a generator, wherein the turbine is at least partially inserted into a fluid flow path of the conduit;
outputting, using a generator, an electrical power signal in response to the activation of the turbine;
determining a characteristic of the electrical power signal;
determining, based on the characteristic, a load impedance selected from a plurality of load impedances; and
outputting a control signal to select the load impedance; and
providing, by a variable load circuit, the load impedance based on the control signal;
wherein an impedance of the variable load circuit is based on the characteristic to provide power generation over various flow rates of fluid in the fluid flow path of the conduit of the irrigation system wherein the variable load circuit comprises:
a load having a nominal load impedance;
a switch coupled to the control circuit; and
a supplemental load comprising one or more additional loads coupled to the switch, wherein the control signal controls the switch to selectively couple and decouple at least one of the one or more additional loads to provide the load impedance selected from the plurality of load impedances.