Assembled DC-AC inverter with overload alarm

Abstract

The utility model relates to the technical field of power electronics, in particular to an assembled DC-AC inverter with an overload alarm function, which comprises a photovoltaic input module, a power supply inversion module and a rectification output module, the photovoltaic input module comprises a shunt and an input filter circuit, the power supply inversion module comprises an overvoltage protection circuit and a DC-AC conversion circuit, and the rectification output module is connected with the shunt and the input filter circuit. The rectification output module comprises an output filter circuit and an overvoltage alarm circuit. According to the utility model, the overvoltage protection circuit preliminarily reduces the DC voltage, then the DC voltage is input into the DC-AC conversion circuit to be converted into AC, the AC is output outwards after high-frequency noise and harmonic waves are filtered out again through the output filter circuit, the overvoltage alarm circuit monitors the circuit in real time, and an alarm is given when the circuit is overloaded. And a worker is notified to turn off the inverter so as to avoid damage.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to an assembled DC-AC inverter with overload alarm. Background Art

[0002] A DC-AC inverter is an important device that converts direct current into alternating current. It is widely used in solar power generation systems and other fields. An assembled DC-AC inverter is a form of photovoltaic inverter that is used to convert the direct current power converted by solar panels into alternating current to meet the requirements of grid access. Its working principle is to use modular power electronic devices to boost the DC end, and then use power electronic devices to invert the AC end to convert DC into AC.

[0003] For example, CN216699861U involves a DC-AC inverter, including a power conversion module, a working power supply module, an input voltage detection module, an output voltage processing module, a main control module, an input module, an output module and a touch display. The power conversion module is provided with a power input interface, an output power interface, a first communication interface and a signal sampling interface. The working power supply module is provided with a first input interface and a first output interface. The touch display is provided with a first power supply interface and a second communication interface. The input module includes a plurality of control switches, the output module includes an alarm device, the output voltage processing module is electrically connected to the signal sampling interface, and the first communication interface and the second communication interface are both It is communicated with the main control module, the input voltage detection module is connected in parallel to the power input interface, and the main control module is electrically connected to the input voltage detection module, the input module and the output module. The inverter can stably output AC380V and can also issue an alarm in time when an abnormality occurs. However, when it is applied to the photovoltaic field, the DC voltage generated by the photovoltaic module will change with the change of light intensity. When the light intensity is too large or other reasons cause the output voltage of the photovoltaic module to exceed the allowable range, the DC terminal voltage of the inverter will be too high. When the inverter performs DC boost and AC-DC conversion, the high voltage DC power can easily cause overload damage to the inverter.

[0004] In order to avoid overload damage caused by the inverter working under high voltage direct current, an assembled DC-AC inverter with overload alarm is proposed. Utility Model Content

[0005] The purpose of the utility model is to provide an assembled DC-AC inverter with an overload alarm to solve the problems raised in the above background technology.

[0006] To achieve the above-mentioned purpose, the utility model provides an assembled DC-AC inverter with overload alarm, comprising a photovoltaic input module, a power inverter module and a rectifier output module, wherein the photovoltaic input module comprises a shunt and an input filter circuit, the power inverter module comprises an overvoltage protection circuit and a DC-AC conversion circuit, the rectifier output module comprises an output filter circuit and an overvoltage alarm circuit, the shunt is connected to the input filter circuit, the input filter circuit is connected to the overvoltage protection circuit, the overvoltage protection circuit is connected to the DC-AC conversion circuit, the DC-AC conversion circuit is connected to the output filter circuit, and the output filter circuit is connected to the overvoltage alarm circuit;

[0007] The direct current generated by the photovoltaic panel is aggregated by the shunt and passes through the input filter circuit. The overvoltage protection circuit reduces the direct current voltage input to the direct-to-alternating conversion circuit, and then the direct-to-alternating conversion circuit completes the inversion to generate alternating current, which is output to the outside through the output filter circuit and the overvoltage alarm circuit. The overvoltage alarm circuit detects the voltage in the circuit in real time.

[0008] As a further improvement of the technical solution, the overvoltage protection circuit includes a chip U1,

[0009] The vin pin of the chip U1 is connected to capacitors C1 and C2 and connected to the input filter circuit;

[0010] The vout pin of the chip U1 is connected to resistors R1, R2, capacitor C4 and connected to the DC-AC conversion circuit;

[0011] The adj pin of the chip U1 is connected to the capacitor C3 and the other end of the resistor R1. The resistor R2 is connected to the light emitting diode LED1. The light emitting diode LED1 is connected to the other end of the capacitor C1, the other end of C2, the other end of C3, and the other end of C4.

[0012] As a further improvement of the technical solution, the overvoltage protection circuit further includes a potentiometer RP1, one end of the potentiometer RP1 is connected to the other end of the resistor R1, and the other end of the potentiometer RP1 is connected to the other end of the light emitting diode LED1.

[0013] As a further improvement of the present technical solution, the vin pin of the chip U1 is connected to a diode D1, and the other end of the diode D1 is connected to the vout pin of the chip U1. In addition, the vout pin of the chip U1 is also connected to a diode D2, and the other end of the diode D2 is connected to the adj pin of the chip U1.

[0014] As a further improvement of the technical solution, the overvoltage alarm circuit includes voltage stabilizing sources T1 and T2.

[0015] The voltage-stabilizing source T1 is connected to the resistors R12 and R16 and connected to the R end of the voltage-stabilizing source T2. The other end of the voltage-stabilizing source T1 is connected to the resistor R15. The voltage-stabilizing source T2 is connected to the other end of the resistor R16. The R end of the voltage-stabilizing source T1 is connected to the resistor R11 and connected to the other end of the resistor R15.

[0016] One end of the voltage stabilizing source T2 is connected to the light emitting diode LED2 and in parallel to the resistor R14. The resistor R14 is connected to the resistor R13 and in parallel to the other end of the light emitting diode LED2. The other end of the resistor R13 is connected to the other end of the resistor R11 and the other end of R12 and in parallel to the output filter circuit.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] In this assembled DC-AC inverter with overload alarm, the overvoltage protection circuit initially reduces the DC voltage, and then inputs it into the DC-AC conversion circuit to convert it into AC power. The AC power is filtered out again by the output filter circuit to remove high-frequency noise and harmonics before being output. The overvoltage alarm circuit monitors the circuit in real time, and issues an alarm when the circuit is overloaded, notifying the staff to shut down the inverter to avoid damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0020] Figure 2 This is the overvoltage protection circuit diagram of the utility model;

[0021] Figure 3 This is the overvoltage alarm circuit diagram of the utility model. DETAILED DESCRIPTION

[0022] 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.

[0023] See also Figure 1-Figure 3As shown, this embodiment provides an assembled DC-AC inverter with overload alarm, including a photovoltaic input module, a power inverter module and a rectifier output module, the photovoltaic input module includes a shunt and an input filter circuit for connecting multiple photovoltaic panels, the power inverter module includes an overvoltage protection circuit and a DC-AC conversion circuit, the rectifier output module includes an output filter circuit and an overvoltage alarm circuit, the shunt is connected to the input filter circuit, the input filter circuit is connected to the overvoltage protection circuit, the overvoltage protection circuit is connected to the DC-AC conversion circuit, the DC-AC conversion circuit is connected to the output filter circuit, and the output filter circuit is connected to the overvoltage alarm circuit;

[0024] The DC power generated by the photovoltaic panels is aggregated by the shunt and passes through the input filter circuit. The overvoltage protection circuit reduces the DC voltage input to the DC-AC conversion circuit, and then the DC-AC conversion circuit completes the inversion to generate AC power, which is output through the output filter circuit and the overvoltage alarm circuit. The overvoltage alarm circuit detects the voltage in the circuit in real time.

[0025] Principle: The shunt collects the DC power generated by multiple photovoltaic panels, and then the high-frequency noise and harmonics are filtered out by the input filter circuit. The overvoltage protection circuit initially reduces the DC voltage, and then the DC voltage is input into the DC-AC conversion circuit to convert it into AC power. The AC power is filtered out again by the output filter circuit to remove high-frequency noise and harmonics before being output. The overvoltage alarm circuit monitors the circuit in real time, and issues an alarm when the circuit is overloaded, notifying the staff to shut down the inverter to avoid damage.

[0026] The overvoltage protection circuit includes chip U1,

[0027] The vin pin of chip U1 is connected to capacitors C1 and C2 and connected to the input filter circuit;

[0028] The vout pin of chip U1 is connected to resistors R1, R2, capacitor C4 and connected to the DC-AC conversion circuit;

[0029] The adj pin of the chip U1 is connected to the capacitor C3 and the other end of the resistor R1. The resistor R2 is connected to the light emitting diode LED1. The light emitting diode LED1 is connected to the other end of the capacitor C1, the other end of C2, the other end of C3, and the other end of C4.

[0030] The chip U1 in this circuit is an integrated circuit LM317. When the DC power input by the input filter circuit passes through the VIN pin of the chip U1, the DC voltage output by the VOUT pin of the chip U1 is determined by the resistor R1, which can convert the input high-voltage DC power into low-voltage DC power.

[0031] The overvoltage protection circuit also includes a potentiometer RP1, one end of the potentiometer RP1 is connected to the other end of the resistor R1, and the other end of the potentiometer RP1 is connected to the other end of the light-emitting diode LED1. By providing the potentiometer RP1 in cooperation with the resistor R1, the voltage of the DC power output by the circuit can be adjusted by adjusting the resistance value of the potentiometer RP1.

[0032] The vin pin of chip U1 is connected to a diode D1, and the other end of diode D1 is connected to the vout pin of chip U1. In addition, the vout pin of chip U1 is also connected to a diode D2, and the other end of diode D2 is connected to the adj pin of chip U1. By providing diodes D1 and D2 as protection diodes, damage to chip U1 due to output short circuit can be avoided, and it can be used to prevent damage to the integrated circuit due to input short circuit.

[0033] The overvoltage alarm circuit includes voltage regulators T1 and T2.

[0034] The voltage stabilizing source T1 is connected to the resistors R12 and R16 and connected to the R end of the voltage stabilizing source T2. The other end of the voltage stabilizing source T1 is connected to the resistor R15, the voltage stabilizing source T2 is connected to the other end of the resistor R16, and the R end of the voltage stabilizing source T1 is connected to the resistor R11 and connected to the other end of the resistor R15.

[0035] One end of the voltage regulator T2 is connected to the light emitting diode LED2 and in parallel to the resistor R14. The resistor R14 is connected to the resistor R13 and in parallel to the other end of the light emitting diode LED2. The other end of the resistor R13 is connected to the other end of the resistor R11 and the other end of R12 and in parallel to the output filter circuit.

[0036] When the voltage value in the output filter circuit is within the normal range, the voltage stabilizer T2 works but the voltage stabilizer T1 does not work, and the light-emitting diode LED2 is turned on and lights up; when the voltage value in the output filter circuit is too high, the voltage stabilizer T1 is turned on but the voltage stabilizer T2 is turned off and does not conduct, and the light-emitting diode LED2 circuit is cut off and does not emit light.

[0037] The assembled DC-AC inverter with overload alarm of the present embodiment, when in use, after the shunt collects the DC power generated by multiple photovoltaic panels, the high-frequency noise and harmonics are filtered out by the input filter circuit, and the DC voltage is initially reduced by the overvoltage protection circuit. When the DC power input by the input filter circuit passes through the VIN pin of the chip U1, the DC voltage output by the VOUT pin of the chip U1 is determined by the resistor R1, and the input high-voltage DC power can be converted into low-voltage DC power, and then input into the DC-AC conversion circuit to be converted into AC power. The AC power is filtered out again by the output filter circuit to remove high-frequency noise and harmonics and then output. The circuit is monitored in real time by the overvoltage alarm circuit. When the voltage value in the output filter circuit is within the normal range, the voltage stabilizer T2 works and the voltage stabilizer T1 does not work, and the light-emitting diode LED2 is turned on and lights up; when the voltage value in the output filter circuit is too high, the voltage stabilizer T1 is turned on, and the voltage stabilizer T2 is turned off and does not conduct, the circuit of the light-emitting diode LED2 is cut off and does not emit light, and the staff is notified to shut down the inverter to avoid damage.

[0038] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. An assembled DC-AC inverter with overload alarm, characterized in that: It includes a photovoltaic input module, a power inverter module and a rectifier output module, wherein the photovoltaic input module includes a shunt and an input filter circuit, the power inverter module includes an overvoltage protection circuit and a DC-AC conversion circuit, the rectifier output module includes an output filter circuit and an overvoltage alarm circuit, the shunt is connected to the input filter circuit, the input filter circuit is connected to the overvoltage protection circuit, the overvoltage protection circuit is connected to the DC-AC conversion circuit, the DC-AC conversion circuit is connected to the output filter circuit, and the output filter circuit is connected to the overvoltage alarm circuit; The direct current generated by the photovoltaic panel is aggregated by the shunt and passes through the input filter circuit. The overvoltage protection circuit reduces the direct current voltage input to the direct-to-alternating conversion circuit, and then the direct-to-alternating conversion circuit completes the inversion to generate alternating current, which is output to the outside through the output filter circuit and the overvoltage alarm circuit. The overvoltage alarm circuit detects the voltage in the circuit in real time.

2. The assembled DC-AC inverter with overload alarm according to claim 1, characterized in that: The overvoltage protection circuit includes a chip U1, The vin pin of the chip U1 is connected to capacitors C1 and C2 and connected to the input filter circuit; The vout pin of the chip U1 is connected to resistors R1, R2, capacitor C4 and connected to the DC-AC conversion circuit; The adj pin of the chip U1 is connected to the capacitor C3 and the other end of the resistor R1. The resistor R2 is connected to the light emitting diode LED1. The light emitting diode LED1 is connected to the other end of the capacitor C1, the other end of C2, the other end of C3, and the other end of C4.

3. The assembled DC-AC inverter with overload alarm according to claim 2, characterized in that: The overvoltage protection circuit further includes a potentiometer RP1 , one end of the potentiometer RP1 is connected to the other end of the resistor R1 , and the other end of the potentiometer RP1 is connected to the other end of the light emitting diode LED1 .

4. The assembled DC-AC inverter with overload alarm according to claim 2, characterized in that: The vin pin of the chip U1 is connected to a diode D1, and the other end of the diode D1 is connected to the vout pin of the chip U1. In addition, the vout pin of the chip U1 is also connected to a diode D2, and the other end of the diode D2 is connected to the adj pin of the chip U1.

5. The assembled DC-AC inverter with overload alarm according to claim 1, characterized in that: The overvoltage alarm circuit includes voltage stabilizers T1 and T2. The voltage-stabilizing source T1 is connected to the resistors R12 and R16 and connected to the R end of the voltage-stabilizing source T2. The other end of the voltage-stabilizing source T1 is connected to the resistor R15. The voltage-stabilizing source T2 is connected to the other end of the resistor R16. The R end of the voltage-stabilizing source T1 is connected to the resistor R11 and connected to the other end of the resistor R15. One end of the voltage stabilizing source T2 is connected to the light emitting diode LED2 and in parallel to the resistor R14. The resistor R14 is connected to the resistor R13 and in parallel to the other end of the light emitting diode LED2. The other end of the resistor R13 is connected to the other end of the resistor R11 and the other end of R12 and in parallel to the output filter circuit.

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