Photovoltaic and commercial power dual-power-supply control system of air conditioner outdoor unit
By constructing a dual power supply control system for photovoltaic and mains power, the problems of voltage adaptation of the photovoltaic bus of the air conditioner outdoor unit and inflexible power supply switching were solved, achieving efficient energy utilization and stable operation.
Patent Information
- Application Number
- CN202511345068.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-19
- Publication Date
- 2025-12-09
AI Technical Summary
Existing photovoltaic power supply systems for air conditioner outdoor units suffer from problems such as inability to directly adapt the photovoltaic bus voltage, high energy conversion losses, and inflexible power supply switching, resulting in low energy utilization and unstable operation.
A dual power supply control system for photovoltaic and mains power of an air conditioner outdoor unit was designed, including a photovoltaic voltage adaptation module, a voltage balancing module, a load driving module and a power supply switching module. The system achieves accurate conversion and balancing of photovoltaic bus voltage through voltage division and current detection, and realizes flexible power supply switching by combining the state combinations of switching devices.
It improves energy efficiency, reduces circuit conversion losses, ensures the operational stability of the air conditioner outdoor unit and the flexibility of power supply, and realizes efficient switching between photovoltaic and mains power.
Smart Images
Figure CN121097918A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to air conditioner outdoor unit power supply technology, in particular to a photovoltaic and commercial power dual-supply control system of an air conditioner outdoor unit. BACKGROUND
[0002] With the transformation of global energy structure to clean and renewable direction, the application of solar photovoltaic technology in civilian field is increasingly popular, and some families and commercial scenarios have equipped independent photovoltaic power supply system to provide green energy support for various electrical equipment. As a high energy consumption device in family and commercial scenarios, the optimization of energy supply mode of air conditioner is of great significance to improve energy utilization efficiency and reduce carbon emission.
[0003] Currently, there are still technical bottlenecks in the combination of air conditioner and photovoltaic power supply system, mainly in the following aspects: The core load (compressor, fan motor) of the household single-phase air conditioner outdoor unit has strict requirements on the continuous reliability of the power supply voltage, and the rated withstand direct current voltage is usually not more than 400V; while the bus voltage of the photovoltaic solar power generation system is generally about 800V direct current. If the photovoltaic bus voltage is directly connected to the air conditioner outdoor unit, it will exceed the voltage tolerance range of the compressor and fan motor, resulting in equipment damage or abnormal operation. Therefore, the photovoltaic bus output direct current voltage cannot be directly supplied to the air conditioner outdoor unit, and the photovoltaic bus output direct current voltage needs to be inverted to commercial power voltage first, and then the commercial power voltage is converted to the direct current voltage required by the equipment by the internal circuit of the air conditioner. This process includes two-stage conversion of photovoltaic direct current to commercial alternating current to air conditioner direct current, and each stage of conversion has circuit loss, resulting in inefficient use of the electrical energy generated by the photovoltaic cell and serious energy waste.
[0004] In addition, the existing air conditioner power supply system lacks flexible power supply switching mechanism, and it is difficult to realize efficient switching of photovoltaic power supply and commercial power supply according to the photovoltaic power supply state (such as voltage fluctuation caused by change of light intensity) and user demand.
[0005] In summary, the existing technology has not solved the core problems of direct adaptation of photovoltaic bus voltage to air conditioner outdoor unit, reduction of electrical energy conversion loss, protection of voltage accuracy and realization of flexible switching of dual power supply, and there is an urgent need for an air conditioner outdoor unit power supply control system that can realize the adaptation of photovoltaic and commercial power supply, improve energy utilization rate and ensure stable operation. SUMMARY
[0006] The technical problem to be solved by the present application is to provide a photovoltaic and commercial power dual-supply control system of an air conditioner outdoor unit, which realizes the adaptation of photovoltaic and commercial power supply, improves energy utilization rate and ensures stable operation.
[0007] The technical solution adopted by the application to solve the above technical problems is: The application discloses a photovoltaic and commercial power dual-supply control system of an air conditioner outdoor unit. The photovoltaic voltage adaptation module is used for dividing the voltage of the photovoltaic bus and converting it into positive and negative direct current voltages suitable for the load of the air conditioner outdoor unit. The voltage balancing module is connected with the photovoltaic voltage adaptation module and is used for detecting and balancing the current of the positive and negative voltages after voltage division. The load driving module is used for driving the compressor and the fan motor of the air conditioner outdoor unit, the fan motor is powered by one direct current voltage after voltage division, and the compressor is powered by another direct current voltage after voltage division. The power supply switching module is connected with the photovoltaic voltage adaptation module, the commercial power and the load driving module respectively and is used for realizing the switching of photovoltaic power supply and commercial power supply, and contains a plurality of switching devices, so that the load driving module selectively accesses the voltage after photovoltaic adaptation or the voltage after commercial power conversion through the on / off state combination of the switching devices.
[0008] Further, the photovoltaic voltage adaptation module comprises a first capacitor, a second capacitor, a first resistor, a second resistor, a third resistor, an eighth resistor, a ninth resistor, a first power switch, a second power switch, a primary winding of a power inductor, a first relay, a sixth relay, a first microprocessor driver, a first voltage source, a second diode and a third diode. The 1-pin of the first relay is connected to the positive pole of the photovoltaic bus voltage, the 2-pin of the first relay is connected to the 2-pin of the first power switch, the 1-pin of the second diode, the 1-pin of the first capacitor and the 1-pin of the first resistor. The 3-pin of the first power switch is connected to the 2-pin of the second power switch and the 1-pin of the power inductor. The 2-pin of the power inductor is connected to the 2-pin of the first capacitor, the 1-pin of the second capacitor, the 2-pin of the second diode, the 1-pin of the third diode, the 2-pin of the first resistor and the 1-pin of the second resistor as a midpoint reference ground. The 3-pin of the second power switch is connected to the 2-pin of the sixth relay, the 2-pin of the third diode, the GND pin of the first microprocessor, the 2-pin of the second capacitor and the 2-pin of the second resistor. The 1-pin of the sixth relay is connected to the negative pole of the photovoltaic bus voltage, the 1-pin of the first power switch is connected to the second output pin of the driver, the 1-pin of the second power switch is connected to the first output pin of the driver, the first input pin of the driver is connected to the first I / O port of the first microprocessor, the second input pin of the driver is connected to the second I / O port of the first microprocessor, the VCC pin of the first microprocessor is connected to the positive pole of the first voltage source, and the GND pin of the first microprocessor is connected to the negative pole of the first voltage source. The eighth resistance and the ninth resistance constitute a voltage sampling circuit between the midpoint reference ground and the negative pole of the photovoltaic bus voltage, the 1 pin of the eighth resistance is connected to the midpoint reference ground, the 2 pin of the eighth resistance is connected to the 1 pin of the ninth resistance and the fifth I / O port of the first microprocessor; the 2 pin of the ninth resistance is connected to the 2 pin of the sixth relay.
[0009] Further, the voltage balance module comprises: a secondary winding of a power inductor, a third resistance, a first diode, a fourth resistance, a fifth resistance, a sixth resistance, a seventh resistance, a third capacitor, a fourth capacitor, a fifth capacitor and a triode; The 3 pin of the power inductor is connected to the 1 pin of the third resistance and the 1 pin of the first diode; the 2 pin of the third resistance is connected to the 4 pin of the power inductor; the 1 pin of the fifth resistance is connected to the 2 pin of the first diode; the 2 pin of the fifth resistance is connected to the 1 pin of the fourth resistance, the 1 pin of the second capacitor and the 2 pin of the fourth capacitor; the 2 pin of the fourth resistance is connected to the 2 pin of the third capacitor and the 2 pin of the third resistance; the 1 pin of the fourth capacitor is connected to the 2 pin of the sixth resistance and the 3 pin of the triode; the 1 pin of the sixth resistance is connected to the positive pole of the first voltage source, the 2 pin of the triode is connected to the 2 pin of the fifth capacitor and the GND pin of the first microprocessor; the 1 pin of the triode is connected to the 1 pin of the fifth capacitor and the 1 pin of the seventh resistance, the 2 pin of the seventh resistance is connected to the fourth I / O port of the first microprocessor; the 2 pin of the fifth capacitor, the 2 pin of the triode, the 2 pin of the third capacitor, the 2 pin of the fourth resistance and the 4 pin of the power inductor are all connected to the 3 pin of the second power switch.
[0010] Further, the load driving module comprises a fan driving circuit and a compressor driving circuit; The fan driving circuit comprises: a second microprocessor, a second voltage source and a first IPM integrated driving circuit; the GND pin of the second microprocessor is connected to the GND pin of the first IPM integrated driving circuit and to the negative pole of the second voltage source; the control port of the second microprocessor is connected to the control port of the first IPM integrated driving circuit, and the VCC pin of the second microprocessor is connected to the positive pole of the second voltage source; the driving port of the first IPM integrated driving circuit is connected to the fan motor; The compressor driving circuit comprises: a third microprocessor, a third voltage source and a second IPM integrated driving circuit; the GND pin of the third microprocessor is connected to the GND pin of the second IPM integrated driving circuit and to the negative pole of the third voltage source; The VCC pin of the third microprocessor is connected to the positive pole of the third voltage source, the control port of the third microprocessor is connected to the control port of the second IPM integrated driving circuit, and the driving port of the second IPM integrated driving circuit is connected to the compressor.
[0011] Further, the power supply switching module comprises a second relay, a third relay, a fourth relay and a fifth relay; the 2-pin of the second relay is connected to the positive pole of the mains input, the 1-pin of the second relay is connected to the 2-pin of the first relay, and the 3-pin of the second relay is connected to the high-voltage input port of the second IPM integrated drive circuit; the 1-pin of the third relay is connected to the negative pole of the mains input, the 2-pin of the third relay is connected to the high-voltage input port of the first IPM integrated drive circuit, and the 3-pin of the third relay is connected to the GND pin of the third microprocessor; the 1-pin of the fourth relay is grounded, the 2-pin of the fourth relay is connected to the positive pole of the mains input, and the 3-pin of the fourth relay is connected to the high-voltage input of the first IPM integrated drive circuit; the 1-pin of the fifth relay is connected to the negative pole of the mains input, the 2-pin of the fifth relay is connected to the GND pin of the first microprocessor, and the 3-pin of the fifth relay is connected to the GND pin of the second microprocessor.
[0012] The present application has the following advantages: (1) The photovoltaic voltage adaptation module in the present application precisely converts the photovoltaic bus 800V or so direct current voltage into 400V or so positive and negative two-way direct current voltage to adapt to the compressor and fan motor of the air conditioner outdoor unit, avoiding the two-stage conversion link in the prior art that the photovoltaic bus voltage needs to be first converted into mains alternating current and then converted into air conditioner direct current, thereby reducing circuit conversion loss, improving photovoltaic power utilization rate, and reducing energy waste.
[0013] (2) Based on the design of the above circuit structure, the voltage signal between the central reference ground and the negative pole can be detected in real time, and when the voltage deviation exceeds the preset range, the first microprocessor can quickly control the switching element to act; at the same time, the voltage balancing module balances the positive and negative voltage loop currents dynamically through current detection and slope compensation when the compressor and fan motor load changes, so as to ensure that the positive and negative voltage precision after voltage division always meets the equipment operation requirements, and avoid air conditioner outdoor unit failure or performance fluctuation caused by voltage imbalance.
[0014] (3) Based on the design of the above circuit structure, the power supply switching module can realize convenient switching between photovoltaic power supply and mains power supply through the on / off combination of multiple switching devices, when the photovoltaic bus voltage is stable and meets the load demand, the system accesses the photovoltaic adaptation voltage to preferentially utilize clean energy; when the photovoltaic power supply is insufficient or the user has specific needs, the system can be quickly switched to mains power supply to ensure the continuous and stable operation of the air conditioner outdoor unit, and the energy economy and power supply reliability are taken into account. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 The structure block diagram of the photovoltaic and mains dual power supply control system of the air conditioner outdoor unit in the embodiment of the present application.
[0016] Figure 2The circuit structure diagram of the photovoltaic and commercial power dual power supply control system of the air conditioner outdoor unit in the embodiment of the application.
[0017] The labels in the figure are explained as follows: K1-K6 are respectively the first to sixth relays; R1-R9 are respectively the first to ninth resistors; C1-C5 are respectively the first to fifth capacitors; Q1 is a first power switch; Q2 is a second power switch; Q8 is a triode; L1 is a power inductor; n1 is a primary coil; n2 is a secondary coil; MCU1 is a first microprocessor; MCU2 is a second microprocessor; MCU3 is a third microprocessor; IPM1 is a first IPM integrated drive circuit; IPM2 is a second IPM integrated drive circuit; D1 is a first diode; D2 is a second diode; DC1 is a first voltage source; DC2 is a second voltage source; and DC3 is a third voltage source. DETAILED DESCRIPTION
[0018] The application aims to provide a photovoltaic and commercial power dual power supply control system of an air conditioner outdoor unit, to realize photovoltaic and commercial power dual power supply adaptation, improve energy utilization rate, and ensure stable operation. The core idea is to build a dual power supply control system including a photovoltaic voltage adaptation module, a voltage balancing module, a load driving module, and a power supply switching module. The photovoltaic voltage adaptation module uses a voltage dividing circuit to divide the photovoltaic bus voltage, and converts the 800V or so DC voltage of the photovoltaic bus into 400V or so positive and negative DC voltages required by the compressor and fan motor. The voltage balancing module acquires positive and negative voltage loop current signals through a current detection element, and dynamically balances the voltage when the load changes, to ensure the accuracy of the divided positive and negative voltages, in combination with a slope compensation element and real-time control of a microprocessor. The load driving module uses two independent integrated drive circuits, which are respectively controlled by different integrated microprocessors, to realize accurate driving of the compressor and fan motor, and the two loads are respectively powered by the divided positive and negative voltages, to adapt to their respective voltage requirements. The power supply switching module flexibly switches between photovoltaic adaptation voltage and commercial power supply through the on / off state combination of multiple switching devices, to preferentially use clean energy and ensure the continuous and stable operation of the air conditioner outdoor unit, and finally to balance the energy utilization efficiency, equipment operation reliability, and power supply flexibility.
[0019] The scheme of the application will be further described below in combination with the drawings and embodiments.
[0020] The embodiment provides a photovoltaic and commercial power dual power supply control system of an air conditioner outdoor unit, which is as shown in the system architecture, Figure 1As shown, the 800V DC voltage output by the photovoltaic module bus is divided into two voltages of +400V (positive pole - midpoint reference ground) and -400V (midpoint reference ground - negative pole) through photovoltaic voltage adaptation; based on the midpoint voltage balancing module, the current changes of the two voltages are detected in real time, and the voltage accuracy is maintained through microprocessor control; the switching switch can select the photovoltaic adaptation voltage or the voltage after the rectification of the mains to access the load driving module according to the photovoltaic power supply state; finally, the two-way IPM integrated driving circuit drives the fan motor and the compressor to run, realizing flexible power supply adaptation of photovoltaic and mains.
[0021] In an exemplary circuit structure design scheme, referring to Figure 2 , the specific description of each part of the circuit composition is as follows: 1. Photovoltaic voltage adaptation module: including first capacitor C1, second capacitor C2, first resistor R1, second resistor R2, third resistor R3, eighth resistor R8, ninth resistor R9, first power switch Q1, second power switch Q2, primary winding n1 of power inductor L1, first relay K1, sixth relay K6, first microprocessor MCU1, driver, first voltage source DC1, second diode D2 and third diode D3.
[0022] The 1 pin of the first relay K1 is connected to the positive pole of the photovoltaic bus voltage, the 2 pin of the first relay K1 is connected to the 2 pin of the first power switch Q1, the 1 pin of the second diode D2, the 1 pin of the first capacitor C1 and the 1 pin of the first resistor R1; the 3 pin of the first power switch Q1 is connected to the 2 pin of the second power switch Q2 and the 1 pin of the power inductor L1; the 2 pin of the power inductor L1 is connected to the 2 pin of the first capacitor C1, the 1 pin of the second capacitor C2, the 2 pin of the second diode D2, the 1 pin of the third diode D3, and is connected to the 2 pin of the first resistor R1 and the 1 pin of the second resistor R2 as a midpoint reference ground; the 3 pin of the second power switch Q2 is connected to the 2 pin of the sixth relay K6, the 2 pin of the third diode D3, the GND pin of the first microprocessor MCU1, the 2 pin of the second capacitor C2 and the 2 pin of the second resistor R2; the 1 pin of the sixth relay K6 is connected to the negative pole of the photovoltaic bus voltage; the 1 pin of the first power switch Q1 is connected to the second output pin out2 of the driver; the 1 pin of the second power switch Q2 is connected to the first output pin out1 of the driver; the first input pin in1 of the driver is connected to the first I / O port I / O-1 of the first microprocessor MCU1; the second input pin in2 of the driver is connected to the second I / O port I / O-2 of the first microprocessor MCU1; the VCC pin of the first microprocessor MCU1 is connected to the positive pole of DC1, and the GND pin of the first microprocessor MCU1 is connected to the negative pole of the first voltage source DC1; the eighth resistor R8 and the ninth resistor R9 constitute a voltage sampling circuit between the midpoint reference ground and the negative pole of the photovoltaic bus voltage, the 1 pin of the eighth resistor R8 is connected to the midpoint reference ground, the 2 pin of the eighth resistor R8 is connected to the 1 pin of the ninth resistor R9 and is connected to the fifth I / O port I / O-5 of the first microprocessor MCU1; the 2 pin of the ninth resistor R9 is connected to the 2 pin of the sixth relay K6.
[0023] When the first relay K1 and the sixth relay K6 are closed, the photovoltaic bus voltage is connected, and the first capacitor C1 and the second capacitor C2 preliminarily divide the voltage to form ±400V voltage; the sampling circuit composed of the eighth resistor R8 and the ninth resistor R9 real-time samples the voltage between the middle point reference ground and the negative electrode of the bus, and transmits to the fifth I / O port I / O-5 of the first microprocessor MCU1; if the MCU1 detects that the voltage is higher than the threshold value (such as 405V) or lower than the threshold value (such as 395V), the PWM signal is output through the first I / O port I / O-1 and the second I / O port I / O-2 to control the driver to drive the first power switch Q1 and the second power switch Q2 to turn on / off: when the voltage is too high, the Q2 conduction time is prolonged, the discharge current of the second capacitor C2 is increased, and the voltage across the second capacitor C2 is reduced; when the voltage is too low, the Q1 conduction time is prolonged, the charging current of C1 to C2 is increased, and the voltage across C2 is increased; through the closed-loop control, it is ensured that the ±400V voltage after voltage division is stable within the preset range.
[0024] 2. Voltage balancing module: including the secondary winding n2 of the power inductor L1, the third resistor R3, the first diode D1, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, the seventh resistor R7, the third capacitor C3, the fourth capacitor C4, the fifth capacitor C5 and the triode Q8; The 3-pin of the power inductor L1 is connected to the 1-pin of the third resistor R3 and the 1-pin of the first diode D1; the 2-pin of the third resistor R3 is connected to the 4-pin of the power inductor L1; the 1-pin of the fifth resistor R5 is connected to the 2-pin of the first diode D1; the 2-pin of the fifth resistor R5 is connected to the 1-pin of the fourth resistor R4, the 1-pin of the second capacitor C2 and the 2-pin of the fourth capacitor C4; the 2-pin of the fourth resistor R4 is connected to the 2-pin of the third capacitor C3 and the 2-pin of the third resistor R3; the 1-pin of the fourth capacitor C4 is connected to the 2-pin of the sixth resistor R6 and the 3-pin of the triode Q8; the 1-pin of the sixth resistor R6 is connected to the positive electrode of the first voltage source DC1, and the 2-pin of the triode Q8 is connected to the 2-pin of the fifth capacitor C5 and the GND pin of the first microprocessor MCU1; the 1-pin of the triode Q8 is connected to the 1-pin of the fifth capacitor C5 and the 1-pin of the seventh resistor R7, and the 2-pin of the seventh resistor R7 is connected to the fourth I / O port I / O-4 of the first microprocessor MCU1; The 2-pin of the fifth capacitor C5, the 2-pin of the triode Q8, the 2-pin of the third capacitor C3, the 2-pin of the fourth resistor R4 and the 4-pin of the power inductor L1 are all connected to the 3-pin of the second power switch Q2.
[0025] When the load of the compressor (positive 400V supply) or the fan motor (negative 400V supply) of the air conditioner outdoor unit changes, the current of the primary winding n1 of the power inductor L1 changes, and the secondary winding n2 induces a corresponding current; the current is limited by the third resistor R3, rectified by the first diode D1, and then divided by the fourth resistor R4 and the fifth resistor R5 to form a voltage signal sent to the first microprocessor MCU1; MCU1 analyzes the signal to determine the current deviation of the positive and negative voltage loops: if the positive voltage loop current is too large (causing the midpoint voltage to deviate), the fourth I / O port I / O-4 controls the triode Q8 to turn on, enhancing the slope compensation, and at the same time adjusting the PWM duty cycle of Q1 to increase the current limiting of the positive voltage loop; if the negative voltage loop current is too large, adjust the PWM duty cycle of Q2 to increase the current limiting of the negative voltage loop. Through the cooperation of current detection and slope compensation, it ensures that the positive and negative voltage accuracies remain stable within the preset range when the load changes, avoiding drive circuit failures caused by voltage imbalance.
[0026] 3. Load driving module: The load driving module comprises a fan driving circuit and a compressor driving circuit; The fan driving circuit comprises a second microprocessor MCU2, a second voltage source DC2 and a first IPM integrated drive circuit IPM1; the GND pin of the second microprocessor MCU2 is connected to the GND pin of the first IPM integrated drive circuit IPM1, and at the same time connected to the negative electrode of the second voltage source DC2; the control port of the second microprocessor MCU2 is connected to the control port of the first IPM integrated drive circuit IPM1, and the VCC pin of the second microprocessor MCU2 is connected to the positive electrode of the second voltage source DC2; the drive port of the first IPM integrated drive circuit IPM1 is connected to the fan motor; The compressor driving circuit comprises a third microprocessor MCU3, a third voltage source DC3 and a second IPM integrated drive circuit IPM2; the GND pin of the third microprocessor MCU3 is connected to the GND pin of the second IPM integrated drive circuit IPM2 and the negative electrode of the third voltage source DC3; The VCC pin of the third microprocessor MCU3 is connected to the positive electrode of the third voltage source DC3, the control port of the third microprocessor MCU3 is connected to the control port of the second IPM integrated drive circuit IPM2, and the drive port of the second IPM integrated drive circuit IPM2 is connected to the compressor.
[0027] When the power supply switching module is connected to the negative 400V voltage (neutral reference ground - negative terminal) and the positive 400V voltage (positive terminal - neutral reference ground) of the photovoltaic adapter, the high-voltage input terminal of the first IPM integrated drive circuit IPM1 is powered, and the high-voltage input terminal of the second IPM integrated drive circuit IPM2 is powered. The second microprocessor MCU2 outputs a PWM control signal to IPM1 according to the control command of the indoor unit of the air conditioner. IPM1 inverts the DC voltage into a three-phase AC voltage and drives the fan motor to run at the set speed. The third microprocessor MCU3 outputs a PWM signal to control IPM2 according to the cooling / heating command of the indoor unit. IPM2 inverts the DC voltage into a three-phase AC voltage and drives the compressor to run at the set frequency.
[0028] If the power supply switching module is connected to the voltage converted from mains power, the working logic of IPM1 and IPM2 is the same, only the power supply source is different.
[0029] 4. Power supply switching module: It includes a second relay K2, a third relay K3, a fourth relay K4, and a fifth relay K5; pin 2 of the second relay K2 is connected to the positive terminal of the mains input, pin 1 of the second relay K2 is connected to pin 2 of the first relay K1, and pin 3 of the second relay K2 is connected to the high-voltage input port of the second IPM integrated driver circuit IPM2; pin 1 of the third relay K3 is connected to the negative terminal of the mains input, pin 2 of the third relay K3 is connected to the high-voltage input port of the first IPM integrated driver circuit IPM1, and pin 3 of the third relay K3 is connected to the GND pin of the third microprocessor MCU3; The fourth relay K4 has its pin 1 grounded, its pin 2 connected to the positive AC input, and its pin 3 connected to the high voltage input terminal of the first IPM integrated driver circuit IPM1. The fifth relay K5 has its pin 1 connected to the negative AC input, its pin 2 connected to the GND pin of the first microprocessor MCU1, and its pin 3 connected to the GND pin of the second microprocessor MCU2.
[0030] Photovoltaic power supply mode: When MCU1 detects that the photovoltaic bus voltage is stable, it controls the second relay K2 to conduct pins 1 and 3, the third relay K3 to conduct pins 2 and 3, the fourth relay K4 to conduct pins 1 and 3, and the fifth relay K5 to conduct pins 2 and 3. At this time, IPM2 is connected to the photovoltaic positive 400V voltage through K2, and IPM1 is connected to the photovoltaic negative 400V voltage through K4 and K3. The system is powered by photovoltaic.
[0031] The mains power supply mode: when the MCU1 detects that the photovoltaic bus voltage is unstable (such as lower than 750V or higher than 850V), the 2th and 3th pins of K2, the 1th and 3th pins of K3, the 2th and 3th pins of K4, and the 1th and 3th pins of K5 are turned on; at this time, the IPM2 is connected to the positive voltage after the mains rectification through K2, the IPM1 is connected to the negative voltage after the mains rectification through K4 and K3, and the system is switched to the mains power supply; the switching process of the two modes is uninterrupted, ensuring the continuous operation of the air conditioner outdoor unit and avoiding shutdown caused by power supply interruption.
[0032] Although the embodiments of the present application have been described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and all of them are within the protection scope of the present application.
Claims
1. A dual power supply control system for an air conditioner outdoor unit, comprising photovoltaic and mains power, characterized in that, This includes a photovoltaic voltage adaptation module, a voltage balancing module, a load drive module, and a power supply switching module; The photovoltaic voltage adapter module is used to divide the photovoltaic bus voltage and convert it into positive and negative DC voltages that are compatible with the load of the air conditioner outdoor unit. The voltage balancing module is connected to the photovoltaic voltage adapter module and is used to detect and balance the current of the positive and negative voltages after voltage division. The load drive module is used to drive the compressor and fan motor of the outdoor unit of the air conditioner. The fan motor is powered by one DC voltage after voltage division, and the compressor is powered by another DC voltage after voltage division. The power supply switching module is connected to the photovoltaic voltage adaptation module, the mains power and load drive module respectively, and is used to switch between photovoltaic power supply and mains power supply. It includes multiple switching devices. By combining the on / off states of the switching devices, the load drive module can selectively connect to the photovoltaic-adapted voltage or the mains-converted voltage.
2. The dual power supply control system for an air conditioner outdoor unit, comprising photovoltaic and mains power, as described in claim 1, is characterized in that... The photovoltaic voltage adapter module includes: a first capacitor (C1), a second capacitor (C2), a first resistor (R1), a second resistor (R2), a third resistor (R3), an eighth resistor (R8), a ninth resistor (R9), a first power switch (Q1), a second power switch (Q2), the primary winding (n1) of a power inductor (L1), a first relay (K1), a sixth relay (K6), a first microprocessor (MCU1), a driver, a first voltage source (DC1), a second diode (D2), and a third diode (D3); Pin 1 of the first relay (K1) is connected to the positive terminal of the photovoltaic bus voltage, and pin 2 of the first relay (K1) is connected to pin 2 of the first power switch (Q1), pin 1 of the second diode (D2), pin 1 of the first capacitor (C1), and pin 1 of the first resistor (R1). Pin 3 of the first power switch (Q1) is connected to pin 2 of the second power switch (Q2) and pin 1 of the power inductor (L1); The power inductor (L1) has its pin 2 connected to the first capacitor (C1), the second capacitor (C2), the second diode (D2), and the third diode (D3), and is also connected to the first resistor (R1) and the second resistor (R2) as a midpoint reference ground. The third pin of the second power switch (Q2) is connected to the second pin of the sixth relay (K6), the second pin of the third diode (D3), the GND pin of the first microprocessor (MCU1), the second pin of the second capacitor (C2), and the second pin of the second resistor (R2); Pin 1 of the sixth relay (K6) is connected to the negative terminal of the photovoltaic bus voltage; pin 1 of the first power switch (Q1) is connected to the second output pin (out2) of the driver; pin 1 of the second power switch (Q2) is connected to the first output pin (out1) of the driver; the first input pin (in1) of the driver is connected to the first I / O port (I / O-1) of the first microprocessor (MCU1); the second input pin (in2) of the driver is connected to the second I / O port (I / O-2) of the first microprocessor (MCU1); the VCC pin of the first microprocessor (MCU1) is connected to the positive terminal of the first voltage source (DC1), and the GND pin of the first microprocessor (MCU1) is connected to the negative terminal of the first voltage source (DC1); The eighth resistor (R8) and the ninth resistor (R9) form a voltage sampling circuit between the midpoint reference ground and the negative terminal of the photovoltaic bus voltage. Pin 1 of the eighth resistor (R8) is connected to the midpoint reference ground, and pin 2 of the eighth resistor (R8) is connected to pin 1 of the ninth resistor (R9) and connected to the fifth I / O port (I / O-5) of the first microprocessor (MCU1). Pin 2 of the ninth resistor (R9) is connected to pin 2 of the sixth relay (K6).
3. The dual power supply control system for an air conditioner outdoor unit, comprising photovoltaic and mains power, as described in claim 2, is characterized in that... The voltage balancing module includes: the secondary winding (n2) of the power inductor (L1), the third resistor (R3), the first diode (D1), the fourth resistor (R4), the fifth resistor (R5), the sixth resistor (R6), the seventh resistor (R7), the third capacitor (C3), the fourth capacitor (C4), the fifth capacitor (C5), and the transistor (Q8). The 3rd pin of the power inductor (L1) is connected to the 1st pin of the third resistor (R3) and the 1st pin of the first diode (D1); the 2nd pin of the third resistor (R3) is connected to the 4th pin of the power inductor (L1); the 1st pin of the fifth resistor (R5) is connected to the 2nd pin of the first diode (D1); the 2nd pin of the fifth resistor (R5) is connected to the 1st pin of the fourth resistor (R4), the 1st pin of the second capacitor (C2), and the 2nd pin of the fourth capacitor (C4); the 2nd pin of the fourth resistor (R4) is connected to the 2nd pin of the third capacitor (C3) and the 2nd pin of the third resistor (R3); the 1st pin of the fourth capacitor (C4) is connected to the 2nd pin of the sixth resistor (R6) and the 3rd pin of the transistor (Q8); Pin 1 of the sixth resistor (R6) is connected to the positive terminal of the first voltage source (DC1). Pin 2 of the transistor (Q8) is connected to pin 2 of the fifth capacitor (C5) and then to the GND pin of the first microprocessor (MCU1). Pin 1 of the transistor (Q8) is connected to pin 1 of the fifth capacitor (C5) and pin 1 of the seventh resistor (R7). Pin 2 of the seventh resistor (R7) is connected to the fourth I / O port (I / O-4) of the first microprocessor (MCU1). Pin 2 of the fifth capacitor (C5), pin 2 of the transistor (Q8), pin 2 of the third capacitor (C3), pin 2 of the fourth resistor (R4), and pin 4 of the power inductor (L1) are all connected to pin 3 of the second power switch (Q2).
4. The dual power supply control system for an air conditioner outdoor unit, comprising photovoltaic and mains power, as described in claim 3, is characterized in that... The load drive module includes a fan drive circuit and a compressor drive circuit; The fan drive circuit includes: a second microprocessor (MCU2), a second voltage source (DC2), and a first IPM integrated drive circuit (IPM1); the GND pin of the second microprocessor (MCU2) is connected to the GND pin of the first IPM integrated drive circuit (IPM1), and is also connected to the negative terminal of the second voltage source (DC2); the control port of the second microprocessor (MCU2) is connected to the control port of the first IPM integrated drive circuit (IPM1), and the VCC pin of the second microprocessor (MCU2) is connected to the positive terminal of the second voltage source (DC2); the drive port of the first IPM integrated drive circuit (IPM1) is connected to the fan motor; The compressor drive circuit includes: a third microprocessor (MCU3), a third voltage source (DC3), and a second IPM integrated drive circuit (IPM2); the GND pin of the third microprocessor (MCU3) is connected to the GND pin of the second IPM integrated drive circuit (IPM2) and the negative terminal of the third voltage source (DC3); The VCC pin of the third microprocessor (MCU3) is connected to the positive terminal of the third voltage source (DC3). The control port of the third microprocessor (MCU3) is connected to the control port of the second IPM integrated drive circuit (IPM2). The drive port of the second IPM integrated drive circuit (IPM2) is connected to the compressor.
5. A dual power supply control system for an air conditioner outdoor unit, comprising photovoltaic and mains power, as described in claim 4, characterized in that, The power supply switching module includes: a second relay (K2), a third relay (K3), a fourth relay (K4), and a fifth relay (K5); pin 2 of the second relay (K2) is connected to the positive terminal of the mains power input, pin 1 of the second relay (K2) is connected to pin 2 of the first relay (K1), and pin 3 of the second relay (K2) is connected to the high-voltage input port of the second IPM integrated driver circuit (IPM2); pin 1 of the third relay (K3) is connected to the negative terminal of the mains power input, pin 2 of the third relay (K3) is connected to the high-voltage input port of the first IPM integrated driver circuit (IPM1), and pin 3 of the third relay (K3) is connected to the GND pin of the third microprocessor (MCU3); The fourth relay (K4) has its pin 1 grounded, its pin 2 connected to the positive AC input, and its pin 3 connected to the high voltage input of the first IPM integrated drive circuit (IPM1). The fifth relay (K5) has its pin 1 connected to the negative AC input, its pin 2 connected to the GND pin of the first microprocessor (MCU1), and its pin 3 connected to the GND pin of the second microprocessor (MCU2).