An electrical conversion and control system for a wave energy power generation device

Abstract

The present invention relates to an electrical conversion and control system for a wave energy power generation device, belonging to the technical field of wave energy power generation. The system is characterized in that it comprises: an electrical conversion circuit for converting AC power input to DC power of the wave energy power generation device and providing a feedback control signal; a battery for receiving and storing DC power output by the electrical conversion circuit; and an inverter for converting DC power output by the battery into AC power. The electrical conversion circuit comprises: a rectifier circuit for receiving three-phase AC power from the wave energy power generation device, converting the three-phase AC power of the wave energy power generation device into DC power, and performing step-up and step-down and voltage stabilization control; a filter circuit for receiving DC power output by the rectifier circuit, filtering the DC power to remove AC components in the DC power; and a feedback control circuit for adjusting charging power according to changes in the output power of the wave energy power generation device, optimizing the power matching relationship, and improving the power conversion efficiency of the wave energy power generation device.

Description

Technical Field

[0001] The present invention belongs to the technical field of wave energy power generation, and in particular relates to an electrical conversion and control system for a wave energy power generation device. Background Art

[0002] Wave power generation converts wave energy into mechanical, pneumatic, or hydraulic energy through a conversion device. This energy is then driven by a transmission mechanism, steam turbine, water turbine, or hydraulic motor to generate electricity. Because wave power generation is powered by waves, and wave motion is highly erratic, the power output from wave power generation devices is unstable and cannot be directly utilized.

[0003] To effectively utilize wave energy resources and improve wave energy conversion efficiency, it is necessary to design an electronic control device that conforms to the power output characteristics of the wave power generation device. A common method is to connect the output end of the wave power generation device's generator to a rectifier circuit, convert the AC power output of the generator into DC power, and store it in a battery bank for use by electrical equipment. However, because the operation of wave power generation devices is significantly affected by waves, the output voltage fluctuates widely and has relatively soft voltage characteristics. The voltage drop under load is large, resulting in unstable power supply and inability to operate continuously. Much of the output energy, especially at low voltages, cannot be used, directly affecting the overall energy conversion efficiency. Summary of the Invention

[0004] The problem to be solved by the present invention is to provide an electrical conversion and control system for a wave energy power generation device, which can be connected to the power output end of the wave energy power generation device (the generator output is three-phase alternating current), convert unstable electrical energy into stable electrical energy, and supply power to the load.

[0005] To solve the above technical problems, the present invention adopts the following technical solution: an electrical conversion and control system for a wave energy power generation device, comprising:

[0006] An electrical conversion circuit for converting AC input power of a wave energy power generation device into DC and providing a feedback control signal;

[0007] A battery that receives and stores the DC power output by the electrical conversion circuit;

[0008] An inverter that converts the direct current outputted by the battery into alternating current; wherein:

[0009] The electrical conversion circuit comprises:

[0010] a rectifier circuit, which receives three-phase alternating current from the wave energy power generation device, converts the three-phase alternating current from the wave energy power generation device into direct current, and performs step-up / step-down and voltage stabilization control;

[0011] a filter circuit, wherein the filter circuit receives the direct current output by the rectifier circuit and performs filtering on the direct current to remove the alternating current component in the direct current;

[0012] Feedback control circuit; the feedback control circuit adjusts the charging power according to the change of the output power of the wave energy power generation device, optimizes the power matching relationship, and improves the power conversion efficiency of the wave energy power generation device.

[0013] Preferably, the input terminal of the rectifier circuit is connected to the three-phase AC output terminal of the wave energy power generation device; the output terminal of the rectifier circuit is connected to the input terminal of the filter circuit, and the output terminal of the filter circuit is connected to the input terminal of the battery through a charger; the input terminal of the feedback control circuit is connected to the sampling circuit of the output terminal of the filter circuit, and the output terminal of the feedback control circuit is connected to the drive circuit of the power conversion controller.

[0014] Preferably, it further comprises a data acquisition module and a data acquisition system (18); the data acquisition module comprises:

[0015] A voltage sensor (9) is used to obtain the output voltage of the power generation device, the rectifier output voltage, and the inverter output voltage;

[0016] The current sensor (10) is used to obtain the output current of the power generation device, the rectifier output current, and the inverter output current.

[0017] The data acquisition module sends the collected analog information to the data acquisition system (18), and the data acquisition system converts the analog information into digital information and sends it to the monitoring host computer through the data transmission module.

[0018] Preferably, it further comprises a voltage sampling sensor (7); the voltage sampling sensor (7) is used to obtain a voltage sampling value at the output end of the rectifier circuit, and the signal output terminal of the voltage sampling sensor (7) is connected to the input terminal of the feedback control circuit.

[0019] Preferably, it also includes: a control cabinet (1) for installing an electrical conversion circuit, and a busbar cabinet (8) for batteries and inverters.

[0020] Preferably, the control cabinet (1) is provided with wiring terminals and a display screen; the wiring terminals include an input terminal connected to the wave energy power generation device, a direct current output terminal, and an alternating current output terminal; and the display screen is connected to the output end of the data acquisition system (18).

[0021] Preferably, the busbar cabinet (8) is provided with output wiring terminals (11), a 24V DC switching power supply (12), input wiring terminals (13), a 48V DC switching power supply (14), an inverter wiring switch (15), a battery wiring switch (16), and a DC busbar (17); wherein:

[0022] Connect the input wiring terminals to the output wiring terminals of the control cabinet;

[0023] The electric energy from the control cabinet will be connected to the DC bus of the bus cabinet;

[0024] The inverter wiring switch, battery wiring switch, 24V DC switching power supply and 48V DC switching power supply are respectively connected to the DC bus;

[0025] The output terminals of the inverter wiring switch are connected to the output terminals of the busbar cabinet, and the output terminals of the busbar cabinet are connected to the inverter;

[0026] The output terminal of the battery connection switch is connected to the battery;

[0027] The output terminal of the 24V DC switching power supply is connected to the 24V power supply device;

[0028] The output terminal of the 48V DC switching power supply is connected to the 48V power supply device.

[0029] Preferably, the rectifier circuit is a three-phase half-wave bridge rectifier circuit.

[0030] Preferably, the filtering circuit is a capacitor filtering circuit.

[0031] Preferably, the feedback control circuit is a voltage feedback control circuit.

[0032] The advantages and positive effects of the present invention are:

[0033] Due to the adoption of the above technical solution, the present invention can provide stable power output to the load after power conversion of the unstable alternating current output by the wave energy power generation device.

[0034] The present invention fixes each electronic module in two standard vertical electric control cabinets, namely a control cabinet and a busbar cabinet, for easy management and control.

[0035] The electrical conversion circuit includes a rectifier circuit, a filter circuit, and a feedback control circuit. It can convert unstable alternating current into stable direct current and effectively improve the power conversion efficiency.

[0036] The busbar cabinet is equipped with terminal blocks, switches, DC busbars, power modules, measuring devices, and a data acquisition system, enabling DC power convergence, energy storage, power output, and power data acquisition and transmission.

[0037] In order to improve the energy conversion efficiency of the wave energy power generation device, the present invention designs a feedback control circuit. First, the sampling sensor reads the rectified voltage. If the voltage is low, it indicates that the input energy of the wave energy power generation device is relatively insufficient. If the charging power is not adjusted at this time, the rectified voltage will continue to be lowered, making the rectified voltage too low to charge the battery. After the feedback circuit is added, when the feedback circuit finds that the rectified voltage is low, it will input the feedback control signal into the drive circuit of the IGBT, the core component that controls the charging power. The drive circuit will control the duty cycle of the IGBT to reduce the output current and charging power. Since P=UI, when the current and power are reduced at the same time, the voltage can be stabilized. When the voltage is constant, the battery can continue to be charged, thereby absorbing more electrical energy, improving the energy conversion capability of the wave energy power generation device under small wave sea conditions, and thereby improving the overall conversion efficiency of the wave energy power generation device. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a structural diagram of a preferred embodiment of the present invention;

[0039] Figure 2 is a system composition diagram of a preferred embodiment of the present invention;

[0040] Figure 3 1 is a circuit diagram of a preferred embodiment of the feedback circuit of the present invention.

[0041] Figure 4 This is the circuit diagram of the preferred embodiment of the control cabinet of the present invention

[0042] Figure 5 This is a circuit diagram of a preferred embodiment of the load of the present invention.

[0043] Figure 6 This is a circuit diagram of a preferred embodiment of the inverter of the present invention.

[0044] Among them: 1. Control cabinet; 2. Capacitor filter; 3. Display screen; 4. Control cabinet terminal; 5. Rectifier; 6. Voltage feedback control circuit; 7. Voltage sampling sensor; 8. Busbar cabinet; 9. Voltage sensor; 10. Current sensor; 11. Output terminal; 12. 24V DC switching power supply; 13. Busbar cabinet terminal; 14. 48V DC switching power supply; 15. Inverter connection switch; 16. Battery connection switch; 17. DC bus; 18. Data acquisition system; 19. Control cabinet; 20. Busbar cabinet; 21. Load; 22. Battery; 23. 12V and 24V DC power supplies; 24. Inverter; 25. Output voltage sampling; 26. Output current sampling; 27. GND; 28. Input voltage sampling; 29. ​​Feedback controller UC3842; 30. IGBT driver M57962L. DETAILED DESCRIPTION

[0045] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0046] Please refer to Figures 1 to 6 :

[0047] The present invention provides an electrical conversion and control system for a wave energy power generation device, comprising:

[0048] An electrical conversion circuit for converting AC input power of a wave energy power generation device into DC and providing a feedback control signal;

[0049] A battery that receives and stores the DC power output by the electrical conversion circuit;

[0050] An inverter that converts the direct current outputted by the battery into alternating current; wherein:

[0051] The electrical conversion circuit comprises:

[0052] a rectifier circuit, which receives three-phase alternating current from the wave energy power generation device, converts the three-phase alternating current from the wave energy power generation device into direct current, and performs step-up / step-down and voltage stabilization control;

[0053] a filter circuit, wherein the filter circuit receives the direct current output by the rectifier circuit and performs filtering on the direct current to remove the alternating current component in the direct current;

[0054] Feedback control circuit; the feedback control circuit adjusts the charging power according to the change of the output power of the wave energy power generation device, optimizes the power matching relationship, and improves the power conversion efficiency of the wave energy power generation device.

[0055] The input terminal of the rectifier circuit is connected to the three-phase AC output terminal of the wave energy power generation device; the output terminal of the rectifier circuit is connected to the input terminal of the filter circuit, and the output terminal of the filter circuit is connected to the input terminal of the battery through a charger; the input terminal of the feedback control circuit is connected to the sampling circuit of the output terminal of the filter circuit, and the output terminal of the feedback control circuit is connected to the drive circuit of the power conversion controller.

[0056] It also includes a data acquisition module and a data acquisition system 18; the data acquisition module includes:

[0057] Voltage sensor 9, used to obtain the output voltage of the power generation device, the rectifier output voltage, and the inverter output voltage;

[0058] The current sensor 10 is used to obtain the output current of the power generation device, the rectifier output current, and the inverter output current.

[0059] The data acquisition module sends the collected analog information to the data acquisition system 18, and the data acquisition system converts the analog information into digital information and sends it to the monitoring host computer through the data transmission module.

[0060] It also includes a voltage sampling sensor 7; the voltage sampling sensor 7 is used to obtain a voltage sampling value at the output end of the rectifier circuit, and the signal output terminal of the voltage sampling sensor 7 is connected to the input terminal of the feedback control circuit.

[0061] It also includes: a control cabinet 1 for installing an electrical conversion circuit, and a busbar cabinet 8 for batteries and inverters.

[0062] The control cabinet 1 is provided with connection terminals and a display screen 3 ; the connection terminals include input terminals connected to the wave energy power generation device, DC output terminals and AC output terminals; the display screen is connected to the output end of the data acquisition system 18 .

[0063] The busbar cabinet 8 is provided with output terminals 11, 24V DC switching power supply 12, input terminals 13, 48V DC switching power supply 14, inverter connection switch 15, battery connection switch 16, and DC bus 17; wherein:

[0064] Connect the input wiring terminals to the output wiring terminals of the control cabinet;

[0065] The electric energy from the control cabinet will be connected to the DC bus of the bus cabinet;

[0066] The inverter wiring switch, battery wiring switch, 24V DC switching power supply and 48V DC switching power supply are respectively connected to the DC bus;

[0067] The output terminals of the inverter wiring switch are connected to the output terminals of the busbar cabinet, and the output terminals of the busbar cabinet are connected to the inverter;

[0068] The output terminal of the battery connection switch is connected to the battery;

[0069] The output terminal of the 24V DC switching power supply is connected to the 24V power supply device;

[0070] The output terminal of the 48V DC switching power supply is connected to the 48V power supply device.

[0071] The rectifier circuit is a three-phase half-wave bridge rectifier circuit.

[0072] The filtering circuit is a capacitor filtering circuit.

[0073] The feedback control circuit is a voltage feedback control circuit 6 .

[0074] See also Figure 2,This system mainly includes: control cabinet circuit 19, busbar cabinet 20, load 21, battery 22, 12V and 24V DC power supply 23 and inverter 24;

[0075] See also Figure 3 The feedback circuit includes: an output current sampling terminal 26; a GND 27; an input voltage sampling terminal 28; a feedback controller UC3842 29 and an IGBT driver M57962L30.

[0076] The system converts the unstable AC power output of a wave energy generator into a stable power output for the load. It includes an electrical conversion circuit, display, terminal blocks, switches, a DC bus, a power module, a measuring device, and a data acquisition system, housed in two standard vertical electrical control cabinets (a control cabinet and a busbar cabinet).

[0077] The electrical conversion circuit includes a rectifier circuit, a filter circuit, and a feedback control circuit. The control cabinet terminals 4 include the wave energy device's input terminals and DC output terminals. The busbar cabinet terminals 13 include DC input terminals, 12V and 24V DC output terminals, and AC output terminals. Switches include an AC power supply switch, a battery connection switch, and an inverter connection switch. The power supply modules include a 24V DC power supply module and a 48V DC power supply module. The measuring device includes a voltage sensor and a current sensor. The data acquisition system includes an analog acquisition and processing module and a data transmission module. This electrical conversion and control system converts the unstable AC output of the wave energy generator into stable DC power. It utilizes a novel feedback control technology that stabilizes the input voltage by controlling the output current, effectively increasing the wave energy generator's power output and improving energy conversion efficiency. It features wide adaptability, stable operation, and high reliability.

[0078] The control cabinet houses the electrical conversion circuit, display screen 3, and control cabinet terminals 4. The busbar cabinet houses the busbar terminals, switches, DC busbars, power modules, measuring devices, and a data acquisition system. The two cabinets are connected via terminals. The electrical conversion circuit in the control cabinet, including rectifier circuits, filter circuits, and feedback control circuits, performs AC-DC conversion of the input power of the wave power generator and provides feedback control to improve power conversion efficiency. The display screen displays real-time operating status, including the current input current and voltage, as well as the output current and voltage. The terminals include power input terminals and output terminals. The power input terminals connect to the wave power generator, while the output terminals connect to the busbar cabinet. The wiring terminals in the busbar cabinet include the input terminals of the control cabinet, DC busbar terminals, power module terminals, and power input terminals of other power generation devices (reserved); the switches include AC power supply switch, battery wiring switch, and inverter wiring switch. The battery wiring switch can connect the battery to the system to store the electricity generated by the system. The inverter wiring switch can connect the inverter to the system and convert DC power into usable standard AC power. The AC power supply switch can provide standard 220V and 380V AC power to the outside. The DC bus converges all the DC power of the system through the wiring terminals. The power modules include 24V DC power modules and 48V DC power modules, which can output 24V and 48V DC power to the outside. The measuring devices include voltage sensors and current sensors, which can collect the voltage and current of the wave power generation device and other power inputs and output them as analog quantities. The data acquisition system includes an analog quantity acquisition module and a data transmission module. The analog quantity acquisition module will convert the analog quantities output by the voltage and current sensors into digital quantities and send them to the monitoring host computer through the data transmission module.

[0079] The electric energy source of the electrical conversion and control system is the electric power input provided by the offshore wave energy power generation device.

[0080] The rectifier circuit is a three-phase half-wave bridge rectifier circuit.

[0081] The filtering circuit is a capacitor filtering circuit.

[0082] The feedback control circuit is a voltage feedback control circuit.

[0083] Working principle:

[0084] When the generator of the wave energy power generation device outputs three-phase AC power, it is connected to the electrical conversion circuit through the terminal 4 of the control cabinet 1. The AC-DC conversion, step-up and step-down and feedback control operations are respectively performed through the rectifier 5, the capacitor filter 2 and the voltage feedback control circuit 6. The input AC voltage is converted into DC power that can charge the battery pack. Then, it is connected to the input terminal 13 of the bus cabinet 8 through the terminal. The bus cabinet collects the DC power through the DC bus (17). The electric energy can be stored in the battery through the battery connection switch 16. The DC power is converted into standard 220V and 380V AC power through the inverter connection switch 15. Then, the DC power is supplied to the AC load through the output terminal 11. The 24V DC switching power supply 12 and the 48V DC switching power supply 14 are both connected to the DC bus to supply power to the DC load. Multiple voltage sensors 9 and current sensors 10 are installed in the busbar cabinet, which can collect voltage and current values ​​at multiple locations and send the collected analog results to the data acquisition system 18. The data acquisition system will convert the analog outputs of the voltage and current sensors into digital quantities and send them to the monitoring host computer through the data transmission module.

[0085] The wave energy electrical conversion and control system achieves voltage boost and voltage regulation by varying the duty cycle of the IGBT switching devices in the rectifier 5. Increasing the duty cycle results in voltage boost, while decreasing it results in voltage reduction. The system's DC bus 17 voltage is determined by the battery pack voltage. If the wave energy generator's input energy is insufficient, the input voltage is pulled down by the load. The feedback circuit reads the output voltage sample 25 and connects it to the feedback controller UC3842 29. After calculation, the feedback controller UC3842 sends the result to the IGBT driver M57962L 30, which in turn adjusts the IGBT's duty cycle, reducing the output current and power. Since electrical power P = UI, as I decreases, P decreases, while U remains constant, allowing the battery pack to continue charging. This significantly alleviates the situation where battery charging is impossible due to insufficient input energy, effectively utilizing marine renewable energy.

[0086] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. An electrical conversion and control system for a wave energy power generation device, characterized in that: At least: An electrical conversion circuit for converting AC input power of a wave energy power generation device into DC and providing a feedback control signal; A battery that receives and stores the DC power output by the electrical conversion circuit; An inverter that converts the direct current outputted by the battery into alternating current; wherein: The electrical conversion circuit comprises: a rectifier circuit, which receives three-phase alternating current from the wave energy power generation device, converts the three-phase alternating current from the wave energy power generation device into direct current, and performs step-up / step-down and voltage stabilization control; a filter circuit, wherein the filter circuit receives the direct current output by the rectifier circuit and performs filtering on the direct current to remove the alternating current component in the direct current; A feedback control circuit; the feedback control circuit adjusts the charging power according to the change of the output power of the wave energy power generation device; the feedback control circuit includes an output current sampling terminal (26), a GND (27), an input voltage sampling terminal (28); a feedback controller UC3842 (29) and an IGBT driver M57962L (30); the DC bus voltage of the control system is determined by the voltage of the battery pack; when the input energy of the wave energy power generation device is insufficient, the input voltage is pulled down by the load, the feedback control circuit reads the value of the output voltage sampling, and connects it to the feedback controller UC3842; the feedback controller UC3842 sends the result to the IGBT driver M57962L after calculation, thereby changing the duty cycle of the IGBT and reducing the output current and output power.

2. The electrical conversion and control system of the wave energy power generation device according to claim 1, characterized in that: The input terminal of the rectifier circuit is connected to the three-phase AC output terminal of the wave energy power generation device; the output terminal of the rectifier circuit is connected to the input terminal of the filter circuit, and the output terminal of the filter circuit is connected to the input terminal of the battery through a charger; the input terminal of the feedback control circuit is connected to the sampling circuit of the output terminal of the filter circuit, and the output terminal of the feedback control circuit is connected to the drive circuit of the power conversion controller.

3. The electrical conversion and control system of the wave energy power generation device according to claim 1, characterized in that: It also includes a data acquisition module and a data acquisition system (18); the data acquisition module includes: A voltage sensor (9) is used to obtain the output voltage of the power generation device, the rectifier output voltage, and the inverter output voltage; A current sensor (10) is used to obtain the output current of the power generation device, the rectifier output current, and the inverter output current; The data acquisition module sends the collected analog information to the data acquisition system (18), and the data acquisition system converts the analog information into digital information and sends it to the monitoring host computer through the data transmission module.

4. The electrical conversion and control system of the wave energy power generation device according to claim 1, characterized in that: It also includes a voltage sampling sensor (7); the voltage sampling sensor (7) is used to obtain a voltage sampling value at the output end of the rectifier circuit, and the signal output terminal of the voltage sampling sensor (7) is connected to the input terminal of the feedback control circuit.

5. The electrical conversion and control system of the wave energy power generation device according to claim 1, characterized in that: Also includes: A control cabinet (1) for installing an electrical conversion circuit, a battery, and a busbar cabinet (8) for an inverter.

6. The electrical conversion and control system of the wave energy power generation device according to claim 5, characterized in that: The control cabinet (1) is provided with connection terminals and a display screen; the connection terminals include an input terminal connected to a wave energy power generation device, a direct current output terminal, and an alternating current output terminal; the display screen is connected to the output end of a data acquisition system (18).

7. The electrical conversion and control system of the wave energy power generation device according to claim 5, characterized in that: The busbar cabinet (8) is provided with output wiring terminals (11), a 24V DC switching power supply (12), input wiring terminals (13), a 48V DC switching power supply (14), an inverter wiring switch (15), a battery wiring switch (16), and a DC busbar (17); wherein: Connect the input wiring terminals to the output wiring terminals of the control cabinet; The electric energy from the control cabinet will be connected to the DC bus of the bus cabinet; The inverter wiring switch, battery wiring switch, 24V DC switching power supply and 48V DC switching power supply are respectively connected to the DC bus; The output terminals of the inverter wiring switch are connected to the output terminals of the busbar cabinet, and the output terminals of the busbar cabinet are connected to the inverter; The output terminal of the battery connection switch is connected to the battery; The output terminal of the 24V DC switching power supply is connected to the 24V power supply device; The output terminal of the 48V DC switching power supply is connected to the 48V power supply device.

8. The electrical conversion and control system of the wave energy power generation device according to claim 1, characterized in that: The rectifier circuit is a three-phase half-wave bridge rectifier circuit.

9. The electrical conversion and control system for a wave energy power generation device according to claim 1, characterized in that: The filtering circuit is a capacitor filtering circuit.

10. The electrical conversion and control system for a wave energy power generation device according to claim 1, characterized in that: The feedback control circuit is a voltage feedback control circuit.

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