Circuit for realizing automatic tracking of local maximum power

Abstract

The utility model discloses a circuit for realizing automatic tracking of local maximum power. The circuit comprises an amplifier U1, a sampling circuit, a comparison circuit and a proportional-integral regulating circuit, the output end of the amplifier U1 is connected with the first end of a resistor R7, the second end of the resistor R7 is connected with the anode of a diode D1, and the cathode of the diode is connected with the voltage feedback pin of the voltage regulation IC module; the sampling circuit collects input electric signals and transmits the input electric signals to the reverse end of the amplifier U1. The same-direction end of the amplifier U1 is connected with a comparison circuit, and the comparison circuit is used for providing comparison voltage Vref for the same-direction end of the amplifier U1; a proportional-integral adjusting circuit is connected between the reverse end and the output end of the amplifier U1; the proportional-integral adjusting circuit comprises a resistor R4 and a capacitor C3, the first end of the resistor R4 is connected with the output end of the sampling circuit, and the second end of the resistor R4 is connected with the output end of the amplifier U1 through the capacitor C3. The whole structure is simple, the number of components is small, circuit wiring is simple, compatibility with an existing voltage regulation IC module is high, and regulation can be achieved only by additionally arranging the circuit on the periphery of the voltage regulation IC module.

Description

Technical Field

[0001] The utility model relates to the field of charging circuits, in particular to a circuit for realizing automatic tracking of local maximum power. Background Art

[0002] The existing DC-DC buck-boost pure hardware circuits on the market can only output constant voltage and constant current, and cannot meet the requirements of adaptive input power changes within a wide voltage range, and cannot automatically track the maximum power of the input power source to charge the battery. For example, when the solar panel is used as the input power source, the input power varies with the light intensity. When the input power decreases, the input voltage also decreases, and the entire system cannot charge the battery. In order to solve the above problems, a circuit that can automatically track the local maximum power is needed. Utility Model Content

[0003] In view of the shortcomings of the prior art, the utility model proposes a circuit for realizing automatic tracking of local maximum power. The specific technical solution is as follows:

[0004] A circuit for realizing automatic tracking of local maximum power, characterized in that:

[0005] It includes an amplifier U1, a sampling circuit, a comparison circuit and a proportional-integral regulation circuit;

[0006] The output end of the amplifier U1 is connected to the first end of the resistor R7, the second end of the resistor R7 is connected to the anode of the diode D1, and the cathode of the diode is connected to the voltage feedback pin of the voltage regulating IC module;

[0007] The sampling circuit collects the input signal and transmits it to the reverse end of the amplifier U1;

[0008] The same-direction terminal of the amplifier U1 is connected to a comparison circuit, which is used to provide a comparison voltage V to the same-direction terminal of the amplifier U1. ref ;

[0009] The proportional-integral regulation circuit is connected between the reverse end and the output end of the amplifier U1;

[0010] The proportional-integral regulation circuit includes a resistor R4 and a capacitor C3. The first end of the resistor R4 is connected to the output end of the sampling circuit, and the second end of the resistor R4 is connected to the output end of the amplifier U1 via the capacitor C3.

[0011] In order to better realize the utility model, it can be further:

[0012] The sampling circuit includes a resistor R1, a resistor R2 and a capacitor C1. The first end of the resistor R1 is an input signal acquisition end, which is connected to the positive electrode of the input source. The second end of the resistor R1 is connected to the negative electrode of the input source via the resistor R2. The capacitor C1 is connected in parallel at both ends of the resistor R2.

[0013] The common end of the resistor R1 and the resistor R2 is connected to the inverting end of the amplifier U1 via the resistor R6.

[0014] Further:

[0015] The comparison circuit includes a resistor R8, a resistor R10 and a capacitor C5. The first branch of the same-direction end of the amplifier U1 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the power supply port, the second branch of the same-direction end of the amplifier U1 is connected to the negative electrode of the power supply voltage via the resistor R8, and the power supply port supplies power to the amplifier U1.

[0016] Furthermore: the voltage regulating IC module is a DC-DC voltage regulating module.

[0017] The beneficial effects of the utility model are:

[0018] The overall structure is simple, with few components, and the circuit wiring is simple. It is highly compatible with the existing voltage regulating IC module. It can be adjusted by simply adding the circuit of the utility model to the periphery of the voltage regulating IC module. When the input power decreases, resulting in a decrease in the input voltage, the input sampling voltage Vs will be lower than the comparison voltage Vref. The amplifier U1 will output an incremental voltage VΔ at the output terminal 1 of the amplifier U1 through the proportional-integral regulation circuit based on the difference between the comparison voltage Vref and the input voltage Vs. The diode D1 acts on the FB pin of the voltage regulating IC to increase the voltage of the voltage feedback pin, so that the voltage regulating IC module reduces the target voltage and thus reduces the output power until it is less than the input power, so that the input voltage rises, and at the same time, the input voltage Vs gradually recovers to the comparison voltage Vref. Due to the action of the proportional-integral regulation circuit, the entire circuit system tends to a steady state. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the circuit diagram of the utility model;

[0020] Figure 2 This is a structural diagram used in the present utility model. DETAILED DESCRIPTION

[0021] 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.

[0022] In the description of the present utility model, it should be noted that the terms "vertical", "upper", "lower", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present utility model. In addition, "first", "second", "third", and "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0023] like Figure 1 and Figure 2 As shown:

[0024] The solar panel is used as the input source and the battery is used as the output source. The solar panel charges the battery through a four-bridge buck-boost circuit. The voltage regulating IC module adopts a standard DC-DC voltage regulating module on the market. The voltage regulating IC module controls the voltage conversion of the four-bridge buck-boost circuit through a PWM signal. The input end of the circuit for automatic local maximum power tracking is used to collect the input voltage of the solar panel, and the output end of the circuit for automatic local maximum power tracking is connected to the voltage feedback pin of the voltage regulating IC module. The voltage feedback pin of the voltage regulating IC module simultaneously collects the voltage output signal of the battery.

[0025] Among them, a circuit for realizing automatic local maximum power tracking includes an amplifier U1, an output end of the amplifier U1 is connected to a first end of a resistor R7, a second end of the resistor R7 is connected to an anode of a diode D1, and a cathode of the diode is connected to a voltage feedback pin of a voltage regulating IC module.

[0026] The sampling circuit collects the solar panel and transmits it to the reverse end of amplifier U1;

[0027] Specifically, the sampling circuit includes a resistor R1, a resistor R2, and a capacitor C1. The first end of the resistor R1 is a signal input end. The first end of the resistor R1 is connected to the positive electrode of the solar panel. The second end of the resistor R1 is connected to the negative electrode of the solar panel via the resistor R2. The capacitor C1 is connected in parallel at both ends of the resistor R2.

[0028] The common terminal of the resistor R1 and the resistor R2 is connected to the inverting terminal of the amplifier U1 via the resistor R6.

[0029] The resistor R1 may be a plurality of resistors connected in series according to the actual sampling voltage, so that the voltage input to the reverse end of the amplifier U1 is within the set maximum voltage value.

[0030] The same-direction terminal of the amplifier U1 is connected to a comparison circuit, which is used to provide a comparison voltage V to the same-direction terminal of the amplifier U1. ref The comparison circuit includes a resistor R8, a resistor R10 and a capacitor C5. The first branch of the same-direction end of the amplifier U1 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the power supply port, and the second branch of the same-direction end of the amplifier U1 is connected to the power supply terminal VCC via the resistor R8. The power supply terminal VCC also supplies power to the amplifier U1;

[0031] A proportional-integral regulation circuit is connected between the inverting end and the output end of the amplifier U1. The proportional-integral regulation circuit includes a resistor R4 and a capacitor C3. A first end of the resistor R4 is connected to a common end of the resistor R1 and the resistor R2.

[0032] Principle of this utility model:

[0033] The comparison circuit is used to provide a comparison voltage Vref to the same direction end of the amplifier U1. The comparison circuit includes a resistor R10, a resistor R8 and a capacitor C5. The comparison voltage Vref = VCC*(R8 / (R8+R10)). The resistor R1, the resistor R2 and the capacitor C1 form a resistor divider to sample the input voltage to obtain an input sampling voltage Vs = VIN*(R2 / (R2+R1)) which enters the reverse end of the operational amplifier. The resistor R6 serves as an input current limiter and the resistor R7 serves as an output current limiter. The cathode of the diode D1 is connected to the voltage feedback pin of the voltage regulating IC module, so that the proportional-integral regulation circuit only plays a regulating role when the input sampling voltage Vs is lower than the comparison voltage Vref. When the input sampling voltage Vs is higher than the comparison voltage Vref, the regulation function of the proportional-integral regulation circuit is turned off.

[0034] When the input power of the solar panel meets the output power, the voltage value of the input sampling voltage Vs is higher than the voltage value of the comparison voltage Vref, and the output terminal 1 of the amplifier U1 will be adjusted to 0V as the target voltage. However, due to the unidirectional conduction of the diode D1, the voltage feedback pin of the voltage regulator IC module only receives the signal of the output sampling voltage, that is, Vout = Vfb*gain, Vfb is the voltage regulation reference of the voltage regulator IC module, please refer to the corresponding data manual for details, and gain is the gain of the output voltage sampling circuit of the voltage regulator IC.

[0035] When the input power of the solar panel decreases, causing the input voltage to drop, the input sampling voltage Vs will be lower than the comparison voltage Vref. The amplifier U1 uses the proportional-integral regulation circuit to output an incremental voltage VΔ at the output terminal 1 of the amplifier U1 based on the difference between the comparison voltage Vref and the input voltage Vs. The incremental voltage VΔ acts on the voltage feedback pin of the voltage regulator IC through the diode D1, thereby increasing the voltage of the voltage feedback pin, causing the voltage regulator IC module to reduce the target voltage and thus reduce the output power until it is less than the input power, causing the input voltage of the solar panel to rise. At the same time, the input sampling voltage Vs gradually recovers to the comparison voltage Vref. Due to the action of the proportional-integral regulation circuit, the entire circuit system tends to a steady state.

[0036] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0037] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A circuit for realizing automatic tracking of local maximum power, characterized in that: It includes an amplifier U1, a sampling circuit, a comparison circuit and a proportional-integral regulation circuit; The output end of the amplifier U1 is connected to the first end of the resistor R7, the second end of the resistor R7 is connected to the anode of the diode D1, and the cathode of the diode is connected to the voltage feedback pin of the voltage regulating IC module; The sampling circuit collects the input electrical signal and transmits it to the reverse end of the amplifier U1; The same-direction terminal of the amplifier U1 is connected to a comparison circuit, which is used to provide a comparison voltage V to the same-direction terminal of the amplifier U1. ref ; The proportional-integral regulation circuit is connected between the reverse end and the output end of the amplifier U1; The proportional-integral regulation circuit includes a resistor R4 and a capacitor C3. The first end of the resistor R4 is connected to the output end of the sampling circuit, and the second end of the resistor R4 is connected to the output end of the amplifier U1 via the capacitor C3.

2. A circuit for realizing automatic local maximum power tracking according to claim 1, characterized in that: The sampling circuit includes a resistor R1, a resistor R2 and a capacitor C1, wherein the first end of the resistor R1 is an input signal acquisition end, which is connected to the positive electrode of the input source, the second end of the resistor R1 is connected to the negative electrode of the input source via the resistor R2, and the capacitor C1 is connected in parallel at both ends of the resistor R2; The common end of the resistor R1 and the resistor R2 is connected to the inverting end of the amplifier U1 via the resistor R6.

3. A circuit for realizing automatic local maximum power tracking according to claim 1, characterized in that: The comparison circuit includes a resistor R8, a resistor R10 and a capacitor C5. The first branch of the same-direction end of the amplifier U1 is connected to the first end of the resistor R10, the second end of the resistor R10 is connected to the power supply port, the second branch of the same-direction end of the amplifier U1 is connected to the negative electrode of the power supply voltage via the resistor R8, and the power supply port supplies power to the amplifier U1.

4. A circuit for realizing automatic local maximum power tracking according to claim 1, characterized in that: The voltage regulating IC module is a DC-DC voltage regulating module.

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