Photovoltaic MPPT (maximum power point tracking) controller for various chargers

Abstract

The utility model discloses a photovoltaic MPPT (Maximum Power Point Tracking) controller for various chargers. Comprising a voltage conversion circuit used for realizing boost or buck-boost, a microcontroller used for performing power regulation by monitoring output voltage and current of a photovoltaic panel in real time, and a feedback circuit used for monitoring voltage output of the photovoltaic panel in real time, according to the utility model, through the cooperation of the voltage conversion circuit, the microcontroller, the feedback circuit and the protection circuit, the feedback circuit monitors the output of the photovoltaic panel in real time, and feeds back the monitored information to the microcontroller, so that the MPPT control module can carry out overvoltage protection on the MPPT control module. The microcontroller carries out MPPT calculation according to feedback information and confirms whether output power needs to be adjusted or not, overvoltage protection can be carried out through the protection circuit, the MPPT controller can be compatible with different types of batteries and chargers, and the application range of the MPPT controller is widened.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic controllers, in particular to a photovoltaic MPPT controller for a variety of chargers. Background Art

[0002] Photovoltaic MPPT controller, namely Maximum Power Point Tracking controller, is a crucial component in solar photovoltaic system. The basic function of MPPT controller is to detect the power generation voltage of solar panels in real time and track the highest voltage and current value (VI) to ensure that the system charges the battery with maximum power output.

[0003] MPPT controllers usually perform their functions through voltage conversion circuits. They continuously detect the current and voltage changes of the photovoltaic array and adjust the duty cycle of the PWM (pulse width modulation) drive signal of the voltage converter according to these changes. The purpose of this is to enable the photovoltaic array to output the maximum power at any given moment.

[0004] As shown in the patent document application number 202021857710.3, an MPPT controller is disclosed, including: a multiplier for producting the signal at the current input end and the signal at the voltage input end, the output end of the multiplier is connected to the input end of the first judgment module, and the first judgment module is used to perform positive and negative judgment on dp / dt; the voltage input end is connected to the input end of the second judgment module, and the second judgment module is used to perform positive and negative judgment on dv / dt, and the output ends of the first judgment module and the second judgment module are respectively connected to the first input end and the second input end of the exclusive OR gate; the output end of the exclusive OR gate is connected to a Type compensator composed of an operational amplifier, and the Type compensator is connected to the controlled device. The MPPT controller provided by the utility model can effectively track the maximum power.

[0005] However, the above MPPT controller needs to be equipped with a special charger adapter to charge the battery, so that the controller is adapted to a single battery, which reduces the versatility of the controller. Therefore, we need to propose a photovoltaic MPPT controller for multiple chargers to solve the above problems, so that it can be suitable for use with multiple chargers and improve the versatility of use. Utility Model Content

[0006] The purpose of the utility model is to provide a photovoltaic MPPT controller for a variety of chargers, which can be compatible with different types of batteries and chargers through the cooperation of a voltage conversion circuit, a microcontroller, a feedback circuit and a protection circuit, thereby improving the application scope of the MPPT controller and solving the problems raised in the background technology.

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a photovoltaic MPPT controller for a variety of chargers, including a voltage conversion circuit for realizing voltage boost or voltage boost / down, a microcontroller for power regulation by real-time monitoring of the output voltage and current of the photovoltaic panel, a feedback circuit for real-time monitoring of the voltage output of the photovoltaic panel, a protection circuit for overvoltage protection of the MPPT control module, and an auxiliary power supply for providing electrical energy to the microcontroller, wherein the microcontroller is electrically connected to the voltage conversion circuit, the feedback circuit, the protection circuit and the auxiliary power supply, respectively, and the output end of the microcontroller is connected to the battery through the output circuit.

[0008] Preferably, the voltage conversion circuit includes a driver U1 for receiving an external voltage, one end of the driver U1 is connected to a Pi compensator, one end of the Pi compensator is connected to a predicted ripple current controller, one end of the predicted ripple current controller is connected to a modulator, one end of the modulator is connected to a transistor Q1, a gate of the transistor Q1 is connected in parallel with a diode D2 and an inductor L1, one end of the inductor L1 is connected to the predicted ripple current controller through an analog-to-digital converter, one end of the diode D2 is connected in parallel with a capacitor C1 and a resistor R2, one of the connection ends of the capacitor C1 and the resistor R2 is connected to the drain of the transistor Q1, and the connection end of the capacitor C1 and the transistor Q1 is provided with an output interface for connecting to a battery, and the other connection ends of the capacitor C1 and the resistor R2 are respectively connected to the predicted ripple current controller and the driver U1 through the analog-to-digital converter.

[0009] Preferably, the microcontroller includes a single-chip computer U2, a VCC end of the single-chip computer U2 is connected to a rectifier DB1 through a resistor R14, one end of the rectifier DB1 is connected to a filter U3 for filtering the input voltage, the other end of the rectifier DB1 is connected in parallel with a capacitor C3 and a resistor R7 and a capacitor C10 arranged in parallel, one of the connection ends of the resistor R7 and the capacitor C10 is connected to an output circuit, a coupler U4 is connected between the single-chip computer U2 and the output circuit, one end of the coupler U4 is connected to a resistor R10 and a resistor R12, one end of the resistor R12 is connected in parallel with a capacitor C9 and a diode D6, one end of the diode D6 is connected to a ground resistor R13, one end of the capacitor C9 is connected to a resistor R11, and one end of the resistor R11 is connected to the output circuit.

[0010] Preferably, the output circuit includes a transformer T1 and a transistor Q3, pin 1 of the single-chip computer U2 is connected to a resistor R5, one end of the resistor R5 is connected to the base of the transistor Q3, and the connecting end of the resistor R5 and the transistor Q3 is connected to a resistor R6, the emitter of the transistor Q3 is connected to pin 5 of the single-chip computer U2, the connecting end of the transistor Q3 and the single-chip computer U2 is connected to a resistor R17, the collector of the transistor Q3 is connected to the transformer T1, one end of the transformer T1 is connected to a diode D5, a resistor R9 and a capacitor C6 arranged in series are connected in parallel to the diode D5, a capacitor C7 and a capacitor C8 are connected in parallel to the connecting end of the diode D5 and the capacitor C6, and both ends of the capacitor C8 are connected to a battery.

[0011] Preferably, the feedback circuit includes a path-guided amplifier OTA1, pin 3 of the path-guided amplifier OTA1 is connected to a resistor R21 for receiving a photovoltaic panel signal, pin 2 of the path-guided amplifier OTA1 is connected in parallel with resistors R23 and R24, pin 8 of the path-guided amplifier OTA1 is connected in parallel with a capacitor C21 and a resistor R22, one end of the resistor R22 is connected to an amplifier U5, one end of the resistor R24 ​​is connected to the output end of the amplifier U5, and the output end of the amplifier U5 is connected to the microcontroller U2.

[0012] Preferably, the protection circuit includes a resistor R31 connected to the photovoltaic panel, one end of the resistor R31 is connected to a coupler U8, one end of the coupler U8 is connected in parallel with a resistor R34 and a resistor R32, one end of the resistor R32 is connected to a resistor R33, one end of the resistor R33 is connected to one end of the resistor R34, the connecting end of the resistor R34 and the resistor R33 is connected to a resistor R35, one end of the resistor R35 is connected to a transistor Q5, the emitter of the transistor Q5 is connected to one end of the coupler U8, a resistor R36 is connected between the emitter and the base of the transistor Q5, the base of the transistor Q5 is also connected to a resistor R37, one end of the resistor R37 is connected in parallel with a transistor Q4 and a diode D8 at one end connected to the single-chip computer U2, the base of the transistor Q4 is connected to the connecting end of the resistor R34 and the resistor R33, and the emitter of the transistor Q4 is connected to the connecting end of the resistor R33 and the resistor R32.

[0013] Preferably, the auxiliary power supply includes a voltage stabilizing chip U44, pin 1 of the voltage stabilizing chip U44 is connected to a ground capacitor C55, pin 2 of the voltage stabilizing chip U44 is connected in parallel to a ground diode D19 and an inductor L11, one end of the inductor L11 is connected to a ground capacitor C66, and the connection end of the ground capacitor C66 and the inductor L11 is connected to pin 4 of the voltage stabilizing chip U44.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] 1. The utility model cooperates with a voltage conversion circuit, a microcontroller, a feedback circuit and a protection circuit. The voltage conversion circuit converts the DC voltage of the photovoltaic panel into a stable and higher DC voltage so as to better charge the battery or supply the load. The feedback circuit monitors the output of the photovoltaic panel in real time and feeds back the monitored information to the microcontroller. The microcontroller performs MPPT calculation based on the feedback information to confirm whether the output power needs to be adjusted. The protection circuit can perform overvoltage protection. It is compatible with different types of batteries and chargers, thereby improving the application range of the MPPT controller.

[0016] 2. The utility model can provide the microcontroller with necessary electrical energy through the auxiliary power supply through the cooperation with the microcontroller, so as to facilitate the real-time wake-up of the microcontroller, reduce the overall energy consumption, and enable the microcontroller to work normally when the main power supply is cut off, thereby reducing the risk of data loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a system block diagram of the utility model;

[0018] Figure 2 The circuit diagram of the voltage conversion circuit of the utility model;

[0019] Figure 3 It is a circuit diagram of the microcontroller of the utility model;

[0020] Figure 4 It is a circuit diagram of the feedback circuit of the utility model;

[0021] Figure 5 A circuit diagram of the protection circuit of the utility model;

[0022] Figure 6 This is a circuit diagram of the auxiliary power supply of the utility model. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] See also Figure 1-6, the utility model provides a technical solution: a photovoltaic MPPT controller for a variety of chargers, including a voltage conversion circuit for realizing voltage boost or voltage boost, a microcontroller for power regulation by real-time monitoring of the output voltage and current of the photovoltaic panel, a feedback circuit for real-time monitoring of the voltage output of the photovoltaic panel, a protection circuit for overvoltage protection of the MPPT control module, and an auxiliary power supply for providing electric energy to the microcontroller, the microcontroller is electrically connected to the voltage conversion circuit, the feedback circuit, the protection circuit and the auxiliary power supply respectively, and the output end of the microcontroller is connected to the battery through the output circuit;

[0025] The voltage conversion circuit includes a driver U1 for receiving an external voltage, one end of the driver U1 is connected to a Pi compensator, one end of the Pi compensator is connected to a predicted ripple current controller, one end of the predicted ripple current controller is connected to a modulator, one end of the modulator is connected to a transistor Q1, a gate of the transistor Q1 is connected in parallel with a diode D2 and an inductor L1, one end of the inductor L1 is connected to the predicted ripple current controller through an analog-to-digital converter, one end of the diode D2 is connected in parallel with a capacitor C1 and a resistor R2, one of the connection ends of the capacitor C1 and the resistor R2 is connected to the drain of the transistor Q1, and the connection end of the capacitor C1 and the transistor Q1 is provided with an output interface for connecting to a battery, the other connection ends of the capacitor C1 and the resistor R2 are respectively connected to the predicted ripple current controller and the driver U1 through the analog-to-digital converter, V in is the input voltage, V o is the output voltage, ADC is the digital-to-analog converter, V ref is the reference voltage, e v is the voltage error. After the control system samples the output voltage, it uses the PI compensator to obtain the reference current i ref , the input of the predicted ripple current control is i ref 、v in and v o , the output is the conduction time T of the main switch tube in one cycle on and the off time T off , this time is provided by the modulator and the driver to provide the driving level of the main switch, completing the control in one cycle.

[0026] The microcontroller includes a single-chip computer U2, a VCC terminal of the single-chip computer U2 is connected to a rectifier DB1 through a resistor R14, one end of the rectifier DB1 is connected to a filter U3 for filtering the input voltage, the other end of the rectifier DB1 is connected in parallel with a capacitor C3 and a resistor R7 and a capacitor C10 arranged in parallel, one of the connection ends of the resistor R7 and the capacitor C10 is connected to an output circuit, a coupler U4 is connected between the single-chip computer U2 and the output circuit, one end of the coupler U4 is connected to a resistor R10 and a resistor R12, one end of the resistor R12 is connected in parallel with a capacitor C9 and a diode D6, one end of the diode D6 is connected to a ground resistor R13, one end of the capacitor C9 is connected to a resistor R11, and one end of the resistor R11 is connected to the output circuit.

[0027] The output circuit includes a transformer T1 and a transistor Q3. Pin 1 of the single-chip computer U2 is connected to a resistor R5. One end of the resistor R5 is connected to the base of the transistor Q3, and a resistor R6 is connected to the connecting end of the resistor R5 and the transistor Q3. The emitter of the transistor Q3 is connected to pin 5 of the single-chip computer U2. The connecting end of the transistor Q3 and the single-chip computer U2 is connected to a resistor R17. The collector of the transistor Q3 is connected to the transformer T1. One end of the transformer T1 is connected to a diode D5. The diode D5 is connected in parallel with a resistor R9 and a capacitor C6 that are arranged in series. The connecting end of the diode D5 and the capacitor C6 is connected in parallel with capacitors C7 and C8. Both ends of the capacitor C8 are connected to a battery.

[0028] The feedback circuit includes a path-guided amplifier OTA1, wherein the 3rd pin of the path-guided amplifier OTA1 is connected to a resistor R21 for receiving a photovoltaic panel signal, the 2nd pin of the path-guided amplifier OTA1 is connected in parallel to resistors R23 and R24, the 8th pin of the path-guided amplifier OTA1 is connected in parallel to a capacitor C21 and a resistor R22, one end of the resistor R22 is connected to an amplifier U5, one end of the resistor R24 ​​is connected to the output end of the amplifier U5, and the output end of the amplifier U5 is connected to the single-chip computer U2. By adjusting the values ​​of the resistors R21, R23, R24 and the capacitor C21, the intensity and type of feedback (positive feedback or negative feedback) can be changed. The path-guided amplifier OTA1 can monitor and adjust the voltage and current signals in real time through its complex internal circuit design and feedback mechanism to ensure the stable operation of the system and the accurate transmission of the signal, so that the feedback circuit can adjust its performance according to actual needs, such as stability, response speed and accuracy.

[0029] The protection circuit includes a resistor R31 connected to the photovoltaic panel, one end of the resistor R31 is connected to a coupler U8, one end of the coupler U8 is connected in parallel with a resistor R34 and a resistor R32, one end of the resistor R32 is connected to a resistor R33, one end of the resistor R33 is connected to one end of the resistor R34, the connection end of the resistor R34 and the resistor R33 is connected to a resistor R35, one end of the resistor R35 is connected to a transistor Q5, the emitter of the transistor Q5 is connected to one end of the coupler U8, A resistor R36 is connected between the emitter and base of the transistor Q5, and a resistor R37 is also connected to the base of the transistor Q5. One end of the resistor R37 is connected in parallel with a transistor Q4 and a diode D8 connected to the single-chip computer U2. The base of the transistor Q4 is connected to the connection end of the resistor R34 and the resistor R33, and the emitter of the transistor Q4 is connected to the connection end of the resistor R33 and the resistor R32. When the overvoltage protection signal In is at a high level, the transistor in U8 is turned on, and VCC is the power supply end of the entire circuit. Vc gives Q4 a base current through R34, Q5 is turned on and enters a saturation state, and the Out end is pulled to a low level by Q4, and the PWM turns off the power supply without output. Q4 also controls the conduction of Q5. When Q4 is turned on, the base current of Q5 reaches the ground through R37, Q5 is turned on, and another base current is provided to Q4 through R35 to maintain the conduction of Q4. Q5 and R36, R37, and R35 form a positive feedback circuit of Q4. When the overvoltage protection circuit is in effect, the circuit is in an abnormal working state. For circuits with output voltage up and down adjustment functions, the overvoltage protection point should be greater than the maximum value of the output voltage increase.

[0030] The auxiliary power supply includes a voltage stabilizing chip U44, pin 1 of the voltage stabilizing chip U44 is connected to a ground capacitor C55, pin 2 of the voltage stabilizing chip U44 is connected in parallel to a ground diode D19 and an inductor L11, one end of the inductor L11 is connected to a ground capacitor C66, and the connection end between the ground capacitor C66 and the inductor L11 is connected to pin 4 of the voltage stabilizing chip U44. The auxiliary power supply can provide the microcontroller with necessary electrical energy, facilitate real-time wake-up of the microcontroller, reduce overall energy consumption, and enable the microcontroller to work normally when the main power supply is cut off, thereby reducing the risk of data loss.

[0031] In summary, the DC voltage of the photovoltaic panel is converted into a stable, higher DC voltage through the voltage conversion circuit, so as to better charge the battery or supply the load. The output of the photovoltaic panel is monitored in real time through the feedback circuit, and the monitoring information is fed back to the microcontroller. The microcontroller performs MPPT calculation based on the feedback information to confirm whether the output power needs to be adjusted. The protection circuit can perform overvoltage protection, which is compatible with different types of batteries and chargers, thereby improving the scope of application of the MPPT controller.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A photovoltaic MPPT controller for multiple chargers, characterized by: It includes a voltage conversion circuit for achieving voltage boost or voltage step-up and step-down, a microcontroller for power regulation by real-time monitoring of the output voltage and current of the photovoltaic panel, a feedback circuit for real-time monitoring of the voltage output of the photovoltaic panel, a protection circuit for overvoltage protection of the MPPT control module and an auxiliary power supply for providing electric energy to the microcontroller. The microcontroller is electrically connected to the voltage conversion circuit, the feedback circuit, the protection circuit and the auxiliary power supply respectively, and the output end of the microcontroller is connected to the battery through the output circuit.

2. A photovoltaic MPPT controller for multiple chargers according to claim 1, characterized in that: The voltage conversion circuit includes a driver U1 for receiving an external voltage, one end of the driver U1 is connected to a Pi compensator, one end of the Pi compensator is connected to a predicted ripple current controller, one end of the predicted ripple current controller is connected to a modulator, one end of the modulator is connected to a transistor Q1, a gate of the transistor Q1 is connected in parallel with a diode D2 and an inductor L1, one end of the inductor L1 is connected to the predicted ripple current controller through an analog-to-digital converter, one end of the diode D2 is connected in parallel with a capacitor C1 and a resistor R2, one of the connection ends of the capacitor C1 and the resistor R2 is connected to the drain of the transistor Q1, and the connection end of the capacitor C1 and the transistor Q1 is provided with an output interface for connecting to a battery, and the other connection ends of the capacitor C1 and the resistor R2 are respectively connected to the predicted ripple current controller and the driver U1 through the analog-to-digital converter.

3. A photovoltaic MPPT controller for multiple chargers according to claim 2, characterized in that: The microcontroller includes a single-chip computer U2, a VCC terminal of the single-chip computer U2 is connected to a rectifier DB1 through a resistor R14, one end of the rectifier DB1 is connected to a filter U3 for filtering the input voltage, the other end of the rectifier DB1 is connected in parallel with a capacitor C3 and a resistor R7 and a capacitor C10 arranged in parallel, one of the connection ends of the resistor R7 and the capacitor C10 is connected to an output circuit, a coupler U4 is connected between the single-chip computer U2 and the output circuit, one end of the coupler U4 is connected to a resistor R10 and a resistor R12, one end of the resistor R12 is connected in parallel with a capacitor C9 and a diode D6, one end of the diode D6 is connected to a ground resistor R13, one end of the capacitor C9 is connected to a resistor R11, and one end of the resistor R11 is connected to the output circuit.

4. A photovoltaic MPPT controller for multiple chargers according to claim 3, characterized in that: The output circuit includes a transformer T1 and a transistor Q3. Pin 1 of the single-chip computer U2 is connected to a resistor R5. One end of the resistor R5 is connected to the base of the transistor Q3, and a resistor R6 is connected to the connecting end of the resistor R5 and the transistor Q3. The emitter of the transistor Q3 is connected to pin 5 of the single-chip computer U2. The connecting end of the transistor Q3 and the single-chip computer U2 is connected to a resistor R17. The collector of the transistor Q3 is connected to the transformer T1. One end of the transformer T1 is connected to a diode D5. The diode D5 is connected in parallel with a resistor R9 and a capacitor C6 that are arranged in series. The connecting end of the diode D5 and the capacitor C6 is connected in parallel with capacitors C7 and C8. Both ends of the capacitor C8 are connected to a battery.

5. A photovoltaic MPPT controller for multiple chargers according to claim 4, characterized in that: The feedback circuit includes a path-guided amplifier OTA1, wherein pin 3 of the path-guided amplifier OTA1 is connected to a resistor R21 for receiving a photovoltaic panel signal, pin 2 of the path-guided amplifier OTA1 is connected in parallel to resistors R23 and R24, pin 8 of the path-guided amplifier OTA1 is connected in parallel to a capacitor C21 and a resistor R22, one end of the resistor R22 is connected to an amplifier U5, one end of the resistor R24 ​​is connected to the output end of the amplifier U5, and the output end of the amplifier U5 is connected to the single-chip computer U2.

6. A photovoltaic MPPT controller for multiple chargers according to claim 5, characterized in that: The protection circuit includes a resistor R31 connected to the photovoltaic panel, one end of the resistor R31 is connected to a coupler U8, one end of the coupler U8 is connected in parallel with a resistor R34 and a resistor R32, one end of the resistor R32 is connected to a resistor R33, one end of the resistor R33 is connected to one end of the resistor R34, the connecting end of the resistor R34 and the resistor R33 is connected to a resistor R35, one end of the resistor R35 is connected to a transistor Q5, the emitter of the transistor Q5 is connected to one end of the coupler U8, a resistor R36 is connected between the emitter and the base of the transistor Q5, the base of the transistor Q5 is also connected to a resistor R37, one end of the resistor R37 is connected in parallel with a transistor Q4 and a diode D8 connected to one end of the single-chip computer U2, the base of the transistor Q4 is connected to the connecting end of the resistor R34 and the resistor R33, and the emitter of the transistor Q4 is connected to the connecting end of the resistor R33 and the resistor R32.

7. A photovoltaic MPPT controller for multiple chargers according to claim 6, characterized in that: The auxiliary power supply includes a voltage stabilizing chip U44, pin 1 of the voltage stabilizing chip U44 is connected to a ground capacitor C55, pin 2 of the voltage stabilizing chip U44 is connected in parallel to a ground diode D19 and an inductor L11, one end of the inductor L11 is connected to a ground capacitor C66, and the connection end between the ground capacitor C66 and the inductor L11 is connected to pin 4 of the voltage stabilizing chip U44.

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