A silicon controlled quasi-frequency conversion method and a single-phase asynchronous motor driving module application of an air conditioner fan

Abstract

The application discloses a silicon controlled quasi-frequency conversion method, which reduces the frequency of output alternating current to 1 / 3 of the original frequency, still maintains the balance of positive and negative waves, is quasi-alternating current with a frequency of about 17 Hz, and realizes quasi-frequency conversion. One wave of phase difference is output in the same triggering mode, and the two waves constitute two-phase quasi-alternating current, which is used to drive a single-phase asynchronous motor and has better starting torque and low-speed running reliability than the original rotating magnetic field generated by a phase-shifting capacitor, and is particularly suitable for adding an idle speed working state to a fixed-frequency air conditioner compressor. The application proposes a simplified fixed-frequency air conditioner simulation frequency conversion effect, an added preset start-stop time interval operation mode, and a working current and temperature sensor air conditioner fault judgment. The quasi-frequency conversion technology of the single-phase asynchronous motor can also be used for fan speed regulation, can simplify the production process of the fan motor, and no longer needs to segmentally wind the wire package for speed regulation and increase the tap lead-out wire or additionally set a speed regulation iron core inductor coil.

Description

Technical Field

[0001] This invention relates to the field of frequency conversion drive control for single-phase asynchronous motors, and particularly to a thyristor quasi-frequency conversion method and its application in the single-phase asynchronous motor drive module for air conditioner fans. Background Technology

[0002] Currently, typical inverter air conditioner compressors use PWM technology to achieve inverter operation. While the operating state is ideal, the implementation cost is high, requiring three pairs of high-power, high-reverse-voltage MOSFETs or IGBTs, along with a KW-level PFC (also requiring high-reverse-voltage, high-power MOSFETs). Once a fault occurs, regardless of whether it's a genuine malfunction or the technician's negligence, the repair cost is extremely high. This raises another issue: can air conditioners be equipped with a self-diagnostic function that can quantitatively display the degree to which the air conditioner deviates from its optimal operating state, or the severity of any problems? If the type of fault can be identified, both parties involved in the repair will avoid acting blindly or haphazardly. The prevalence and urgency of this issue stems from the widespread use of high-rise buildings. Even if the air conditioner user is a professional, their fear of heights prevents them from climbing out of the window to check for faults in the outdoor unit. Over time, air conditioner repair has become a hotbed for overcharging; repairs are fabricated, with parts replaced, refrigerant added, etc., without the user noticing. An even more worrying scenario is that repairmen, after risking great danger to climb outside the window to inspect the air conditioner's outdoor unit, discover that the common problem is a faulty compressor phase-shifting capacitor. However, the phase-shifting capacitor they were using had a capacitance value 10uF higher than normal. The repairman would likely simply replace it, claiming it's fixed once it works, without informing the user that the capacitor value was 10uF higher. This would cause the operating current to far exceed the standard, increasing power consumption by 20% and masking the problem of a refrigerant shortage (a gradual decrease in the operating current of a fixed-frequency air conditioner usually indicates a refrigerant shortage).

[0003] Based on the temperature sensors and compressor operating current of existing fixed-frequency air conditioners, which enable self-checking of the air conditioner's working status, fixed-frequency air conditioners have a natural advantage due to the fixed operating parameters of their compressors and capillary tubes. Therefore, fixed-frequency air conditioners have ushered in a new development model. However, variable-frequency air conditioners, which employ complex technology, face challenges: their price is almost double that of fixed-frequency air conditioners, but their cooling effect is limited. Close examination in small rooms reveals that the main problem with fixed-frequency air conditioners is their sluggish temperature adjustment; they continue cooling for a long time, and even after cooling stops, they don't start cooling again for a long time. Adjusting the temperature doesn't solve the problem. Surprisingly, many variable-frequency air conditioners also have this issue. In fact, solving this problem isn't limited to ideal variable-frequency air conditioners. If the fixed-frequency air conditioner compressor can withstand frequent start-stop cycles, the problem can be transformed. According to this technical approach, a low-speed operation mode can be added to the fixed-frequency air conditioner compressor. Each start-stop cycle of the compressor would involve a low-speed buffer transition (also called soft start), achieving short-interval idling start-stop cooling, thus allowing fixed-frequency air conditioners to also provide a new cooling experience. To put it more directly, the breakthrough in solving this problem lies in supplementing the single-phase asynchronous motor of the fixed-frequency air conditioner compressor with a low-speed, high-torque drive mode (referred to as: quasi-frequency variable phase-shift drive).

[0004] To summarize the above complex issues, we can draw two conclusions: 1. To achieve self-checking of air conditioner operation, the air conditioner's structure must be streamlined and typical, and fixed-frequency air conditioners have a natural advantage; 2. Fixed-frequency air conditioners can also avoid the problem of prolonged overheating or overcooling by shortening the compressor start-stop interval, provided that a low-speed, high-torque mode is added to the single-phase asynchronous motor and a compressor idling operation state is supplemented.

[0005] Single-phase asynchronous motors supplement the quasi-frequency low-speed operation mode and simplify the production process of fan motors, eliminating the need for segmented winding of coils for speed control, additional taps, or separate speed-regulating iron core inductors. Especially with the addition of an MCU microcontroller for control, the functionality can be designed to be highly practical, convenient, and flexible, while remaining inexpensive (e.g., the domestic STC15 series and STC8G series, with prices listed in the technical documents: 1-2 yuan). For example, a fan speed control module can switch fan speeds simply by turning the power on and off, thus requiring only a self-locking push-button power switch for both speed control and operation—simple and reliable. Summary of the Invention

[0006] To address the aforementioned issues, this invention provides a two-phase quasi-frequency conversion method. This method reduces the frequency of the output AC wavenumber to one-third of its original value while maintaining a balanced alternation of positive and negative waves, resulting in a quasi-AC frequency of approximately 17Hz. This achieves quasi-frequency conversion, thus eliminating the need for an additional PWM controller to enable frequency conversion.

[0007] A two-phase quasi-frequency conversion method based on thyristors, wherein the control circuit of the thyristor includes an MCU microcontroller, a BCR thyristor, and a power supply section. The MCU microcontroller selectively triggers the thyristor to conduct and output according to the alternating positive and negative wave sequence of the AC power, so that the frequency of the output AC wavenumber is reduced to 1 / 3 of the original, while still maintaining the alternating balance of positive and negative waves, which is a quasi-AC power with a frequency of 16.67Hz.

[0008] The selective triggering rule for the thyristor to conduct output is as follows: starting from the positive wave trigger output, the next negative and positive waves will not trigger or output, and the next negative wave will trigger the output; that is, each time two waves are output at a time interval of one cycle, and the output waves are still alternating between positive and negative, with a frequency of 1 / 3 of the original, thus achieving frequency reduction and obtaining the first quasi-AC power with a frequency of 16.67Hz.

[0009] The same rules are used to output a second quasi-AC current. The first quasi-AC current and the second quasi-AC current have a phase difference of 10ms. The first quasi-AC current and the second quasi-AC current are combined to form a two-phase quasi-AC current for driving a single-phase asynchronous motor, referred to as two-phase quasi-frequency conversion AC current or two-phase quasi-frequency conversion method.

[0010] The present invention also provides a single-phase asynchronous motor drive module for an air conditioner compressor based on a two-phase quasi-frequency conversion method. Based on the original phase-shifting capacitor operation mode, a quasi-low-frequency two-phase operation mode is added to obtain that the air conditioner compressor first goes through a low-speed transition when starting.

[0011] The function of the single-phase asynchronous motor drive module for air conditioning is as follows: When the two compressor power supply lines from the indoor unit of the air conditioner connected to port (1) are powered on, the thyristor control circuit of the single-phase asynchronous motor drive module for air conditioning outputs a two-phase quasi-AC power with a frequency of 16.67Hz at the output connection points of BCR1 and BCR2 on the 4-wire connection port (2), which is used to drive the single-phase asynchronous motor of the air conditioner compressor to perform low-speed operation transition when starting; after a few seconds, the thyristors BCR1 and BCR3 change to full-wave triggering and BCR2 does not trigger. The output points of BCR1 and BCR3 on the 4-wire connection port (2) output the same full-wave AC power, which is to change to the normal operation mode of the motor composed of the original phase-shifting capacitor;

[0012] For circuit designs that continue to use relays or / and in high-power air conditioning applications, the full-wave conduction switching of BCR1 and BCR3 can be replaced by relay contacts J1 and J2. The normally closed contacts of relays J1 and J2 normally switch to the two-phase quasi-low-frequency AC mode formed by BCR1 and BCR2 for low-speed start-up transition. After a few seconds of start-up buffer, the contacts of relays J1 and J2 switch to the main winding of the motor directly connected to the AC input, and the auxiliary winding of the motor connected to the phase-shifting capacitor C in series with the AC input, entering the normal operating mode of the motor formed by the original phase-shifting capacitor.

[0013] Specifically, the application method of the single-phase asynchronous motor drive module for the air conditioner compressor includes:

[0014] Application method A: The original air conditioner main control board is not modified. The two compressor power supply lines in the original air conditioner outdoor unit connection are connected to the AC input connection port (1) of the single-phase asynchronous motor drive module of the air conditioner compressor. The communication control interface SIP4 (3) is not used, so that the fixed frequency air conditioner compressor goes through low speed operation transition every time it starts.

[0015] Application Method B adds a time-based operating mode to the original fixed-frequency air conditioner main control board, allowing users to set the compressor's operation or shutdown. The air conditioner remote control also includes this time-based setting function. When the fixed-frequency air conditioner compressor stops working, it includes both low-speed operation of the compressor motor and an idling state, where the compressor motor is driven by a 16.67Hz two-phase quasi-AC current, normalizing frequent short-interval start-stop cycles. This not only produces an effect similar to that of an inverter air conditioner but, more importantly, provides a test mode for detecting fixed-frequency air conditioners. It allows for alternating operation and idling times with a minimum interval of one minute. During test mode operation, readings from various temperature detection points and the compressor's operating current are sent to the user's computer or mobile phone, allowing the user to diagnose air conditioning system problems. Users can also input actual measured data into the air conditioner to correct for differences between the local installation environment and the standard testing environment, creating a more accurate basis for the self-test function.

[0016] Setting or control commands are communicated to the driver module via the communication control interface SIP4(3);

[0017] Application Method C: The original fixed-frequency air conditioner main control board and remote control remain unchanged. A timed infrared remote control device is added to the original fixed-frequency air conditioner. The timed infrared remote control device records the button codes of the two air conditioner remote controls. After the timed infrared remote control device records the infrared codes for the lowest temperature cooling and no cooling, the timed infrared remote control device will periodically send the recorded two types of infrared codes in a loop. The time interval for the loop can also be set to 5 minutes or 10 minutes. The timed infrared remote control device can be rechargeable or plugged in. It is plugged in near the air conditioner and the infrared emitter is rotated to point at the indoor unit of the air conditioner.

[0018] Application Method D: To broaden the application flexibility of the single-phase asynchronous motor drive module for the air conditioner compressor, the single-phase asynchronous motor drive module for the air conditioner compressor can also add the following functions:

[0019] a. The instantaneous power failure of the AC input connection port (1) is used as a control command: if no power failure occurs within 2 seconds of power-on, it will run at full speed after normal soft start until power failure; if there are several power failures of 0.5 seconds within 2 seconds of power-on, it will be used as a control command. For example, one power failure means running for 5 minutes and stopping for 5 minutes in a cycle, two power failures mean running for 10 minutes and stopping for 5 minutes in a cycle, and three power failures mean running for 5 minutes and stopping for 10 minutes in a cycle.

[0020] b. Connect to the communication control interface SIP4(3) with a 3-core or 4-core long connecting cable to control the logic level combination;

[0021] c. Connect to the communication control interface SIP4(3) with a 3-core or 4-core long twisted pair cable for RS serial communication control. Complex control, including setting various time parameters, must be recorded in the Flash EEPROM of the MCU microcontroller and will not be lost when power is off.

[0022] d. Use a wireless module to connect to the MCU microcontroller via the SPI serial interface to wirelessly set the low-speed start delay and / or high and low speed operation timed cycle rules of the air conditioner compressor.

[0023] The present invention also provides a speed control module for a single-phase asynchronous motor of a fan based on a two-phase quasi-frequency conversion method. Based on the original phase-shifting capacitor operation mode, a quasi-low-frequency two-phase operation mode is added to obtain an additional low-speed operation mode for the fan motor.

[0024] The function of the single-phase asynchronous motor speed control module of the electric fan is as follows: When the AC input connected to port (1) is powered on, the thyristor control circuit of the single-phase asynchronous motor speed control module outputs a two-phase quasi-AC power with a frequency of 16.67Hz at the output connection points of BCR1 and BCR2 on the 4-wire connection port (2), which is used for the electric fan motor to run at low speed normally; by plugging and unplugging the power supply or the button switch to cut off and then turn on the power, the microcontroller recognizes this instantaneous power cut control command, and the thyristors BCR1 and BCR3 are converted to full-wave triggering and BCR2 is not triggered. The output connection points of BCR1 and BCR3 on the 4-wire connection port (2) output the same full-wave AC power, that is, the motor changes to the full-speed running mode composed of the original phase-shifting capacitor;

[0025] For circuit designs that continue to use relays, the full-wave conduction switching of BCR1 and BCR3 can be replaced by relay contacts J1 and J2. Normally, the normally closed contacts of relays J1 and J2 switch to the two-phase quasi-low-frequency AC mode formed by BCR1 and BCR2, which is the low-speed operation of the fan. Once there is a momentary power failure control switch, the contacts of relays J1 and J2 switch to the main winding of the motor directly connected to the AC input, and the auxiliary winding of the motor connected to the phase-shifting capacitor C in series with the AC input, entering the full-speed operation mode of the motor formed by the original phase-shifting capacitor.

[0026] Preferably, the application method of the single-phase asynchronous motor drive module of the air conditioner compressor further includes upgrading the test mode function to a self-test function of a fixed-frequency air conditioner. The self-test process is started by pressing a button or operating a remote control. Based on the several temperature sensors and compressor operating current set in the existing fixed-frequency air conditioner, it automatically sets a specific time interval for working / idling operation. It makes a judgment on the air conditioner operation problem or fault based on the temperature difference and current changes of each temperature sensor caused by the change of operating state. The self-test results are displayed digitally on the display screen of the air conditioner indoor unit or sent to a computer or / and mobile phone via wireless network.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] (1) The two-phase low-frequency quasi-AC power realized by the microcontroller and thyristor is used to drive a single-phase asynchronous motor. It has better starting torque and low-speed operation reliability than the rotating magnetic field generated by the phase-shifting capacitor. It is particularly suitable for applications that require high torque and low speed for soft start transition or long-term safe low-speed operation, such as the simulation of frequency conversion effect of fixed frequency air conditioner, or the addition of a compressor operation mode with preset start and stop time intervals (short interval idle start and stop). Based on this, a simplified air conditioner with the idle working state of fixed frequency air conditioner compressor has been developed, and a self-check function of fixed frequency air conditioner working status has been added, which can quantitatively display the degree of deviation of the air conditioner from the optimal working state, or the severity of the problem.

[0029] (2) This quasi-frequency conversion drive technology for single-phase asynchronous motors can also be used for fan speed control, which simplifies the production process of fan motors. It eliminates the need for segmented winding of coils for speed control, adding taps and leads, or setting up separate speed-regulating iron core inductors. Combined with microcontroller control, it is more flexible and convenient to use. The fan speed can be switched simply by turning the power on or off. From then on, the fan only needs a self-locking button power switch to control the speed, which is simple and reliable. Attached Figure Description

[0030] Figure 1 This is a diagram of a thyristor quasi-frequency conversion single-phase asynchronous motor drive module;

[0031] Figure 2 This is a diagram of the quasi-frequency conversion phase shifting method and structure of silicon controlled rectifier (SCR).

[0032] Figure 3 This is a connection diagram of an AC non-isolated monolithic IC switching power supply with the positive terminal connected to a thyristor.

[0033] Figure 4 This is a connection diagram of the negative terminal of an AC non-isolated monolithic IC switching power supply connected to a thyristor.

[0034] Figure 5 It is a circuit that uses a relay to switch between high and low speed operating modes;

[0035] Figure 6 This is a circuit that requires a diode for unidirectional isolation power supply to control the microcontroller during power outages;

[0036] Figure 7 It is a circuit where the negative terminal of the AC isolation power supply module is connected to a diode for unidirectional isolation power supply;

[0037] Figure 8 It is a circuit that drives a thyristor using a capacitor-based energy storage transistor.

[0038] In the diagram: 1. AC input connection port; 2. 4-wire connection port for motor main and auxiliary windings and phase-shifting capacitor; 3. Communication control interface SIP4; 4. Single-phase asynchronous motor M; 5. Phase-shifting capacitor C. Detailed Implementation

[0039] In this embodiment, the serial numbers are represented by numbers (1, 2, 3, etc.), and the part numbers in the figure are referenced by parentheses or letters, such as: AC input connection port (1), thyristor BCR1.

[0040] The breakthrough of this invention lies in converting single-phase AC power into two-phase quasi-low-frequency AC power to drive a single-phase asynchronous motor, thus adding a low-speed operating mode. Furthermore, the power device used is a bidirectional thyristor with strong overload capacity (difficult to burn out), which is inexpensive, easy to drive, and allows for direct bidirectional AC operation, conveniently triggered by an MCU microcontroller. The purpose of this invention is to enable the use of thyristor-based two-phase quasi-low-frequency AC power in single-phase asynchronous motors in fixed-frequency air conditioner compressors or AC fans, producing unprecedented practical results. This invention is proposed on three levels: the method of using thyristors to implement two-phase quasi-low-frequency AC power (1, 6, 7), the single-phase asynchronous motor drive module implemented with two-phase quasi-low-frequency AC power (2, 4, 5), and the supporting application methods of the air conditioner compressor motor drive module (3, 8).

[0041] 1. A quasi-frequency conversion method for thyristors consisting of an MCU microcontroller, a BCR thyristor, and a power supply section (see...) Figure 2 Above), a microcontroller selectively triggers the thyristor to conduct and output based on the alternating positive and negative wave sequence of the AC current (see above). Figure 2Below, the frequency of the output AC wavenumber is reduced to 1 / 3 of the original, while maintaining a balanced alternation of positive and negative waves, resulting in a quasi-AC frequency of approximately 17Hz. The wave-triggered output rule is as follows: starting from the positive wave triggering output, the next positive and negative wave will not trigger an output, and the next negative wave will trigger an output; that is, two waves are output at a time interval of one full cycle, and the output waves still alternate between positive and negative, with a frequency of 1 / 3 of the original, thus achieving frequency reduction. Another output is given using the same rule, with the two outputs differing by one wave by 10 milliseconds. These two outputs constitute a two-phase quasi-AC (referred to as two-phase quasi-frequency conversion AC or two-phase quasi-frequency conversion method), used to drive a single-phase asynchronous motor for low-speed operation. This method offers better starting torque and low-speed operation reliability compared to the original method of using a phase-shifting capacitor to generate a rotating magnetic field.

[0042] Using a bidirectional thyristor (BCR) to directly control AC power offers significant convenience and reliability. Because it directly connects to the AC power supply for on / off switching (unlike transistors, which require first converting to high-voltage stable DC and then back to AC via a full-bridge PWM drive, typically employing three pairs of high-power, high-reverse-voltage MOSFETs or IGBTs, along with a kW-level PFC circuit and high-reverse-voltage, high-power MOSFETs; current inverter air conditioners use this method), it possesses over 8 times the short-time overload capacity (unlike the two PN junctions of a transistor, which are immediately broken down by high voltage if the rated operating conditions are exceeded).

[0043] The control circuit design revolves around the BCR (Silicon Controlled Rectifier) ​​thyristor, which draws power from AC to power the MCU (Microcontroller Unit) and trigger the thyristor. Its characteristics are as follows: One of the positive and negative terminals of the DC low-voltage regulated output used by the MCU (220V AC) is connected together with the AC power terminal and the T1 terminal of the BCR thyristor (see...). Figure 2 (Top left) By connecting the microcontroller's output port in series with a resistor, it can be directly connected to the trigger terminal G of the thyristor. The T2 terminal of the BCR thyristor is the AC control output terminal.

[0044] There are multiple such BCR paths, such as BCR1, BCR2, and BCR3 (see...). Figure 1 Their T1 terminals are all connected to one end of the AC power supply (e.g., L), and T2 terminals are the output terminals of each circuit. The G terminal of each BCR is connected to multiple output terminals of the microcontroller (in practice, there are series resistors or optocouplers for isolation). Overvoltage absorption resistors, capacitors, or varistors are usually connected in parallel between T1 and T2 of each BCR. Specific details regarding whether the thyristor BCR is isolated or non-isolated and connected to the microcontroller output port, or whether the positive terminal of the DC low-voltage regulated output is connected to the T1 terminal of the BCR / or the negative terminal is generally not discussed further, and they are collectively referred to as BCR1, BCR2, BCR3, etc. The other common terminal of the control output AC power of each BCR is also a collinear common terminal with the other common terminal of the input AC power (e.g., N) (see...). Figure 1 ).

[0045] To obtain the starting points of each wave in the input AC waveform, the MCU microcontroller has an input port connected in series with a high-impedance resistor R, which is then connected to the other end of the AC power supply (e.g., N) to obtain the zero-crossing information of the AC waveform. This is called the AC wave sampling resistor R. See [link to documentation]. Figure 2 The two images above are shown on the left and right. This input port of the MCU microcontroller operates in interrupt mode. After the AC power is stepped down by the high-impedance resistor R, an interrupt program is started at each zero crossing (usually the falling edge) as the basis for wave-by-wave control of the AC power. After a delay, the corresponding thyristor BCR is triggered to conduct.

[0046] However, these are just the general basic connection points. The specific details will be further explained in sections 6 and 7 below, depending on the type of air conditioning main control board used in the application and the supply situation of the components used.

[0047] 2. This embodiment provides a drive module for a single-phase asynchronous motor of an air conditioning compressor based on a two-phase quasi-frequency conversion method using thyristors (see...). Figure 1 That is, in addition to the normal (high-speed) operation mode formed by the original phase-shifting capacitor, a single-phase asynchronous motor drive module (hereinafter referred to as the drive module) with two-phase quasi-low frequency AC for low-speed start-up transition as described in 1 is added. Its function is to add the low-frequency two-phase low-speed mode described in 1 to the original high-speed operation mode of the phase-shifting capacitor. Each time the compressor starts and stops, it goes through a low-speed buffer transition (also called soft start). The characteristics of the drive module installation and use (emphasizing simplicity, ease of use, and convenient installation without changing the existing fixed-frequency air conditioner) are a business card-sized circuit board (or with a plastic shell) installed near the compressor of the outdoor unit of the fixed-frequency air conditioner. In addition to the circuit components described in 1 (power supply, thyristors BCR1, BCR2, BCR3, MCU microcontroller, AC wave sampling resistor R), it also has an AC input connection port (1), a 4-wire connection port (2), and a communication control interface SIP4 (3). The AC input connection port (1) is used to connect the two compressor power supply lines from the indoor unit of the fixed frequency air conditioner; the connection points in the 4-wire connection port (2) are the three T2 output terminals of the thyristors BCR1, BCR2, and BCR3 and one AC power terminal that is common to one pole in the AC input connection port (1), which are connected in sequence to the main winding, auxiliary winding, phase-shifting capacitor, and common terminal of the main and auxiliary windings of the air conditioner compressor motor; the four pins of the communication control interface SIP4 (3) are: +5VRX TX-5V, which can be used for logic level control and RS serial communication.

[0048] The functional characteristics of the drive module are as follows: When the AC input connection port (1) is powered on, according to the AC waveform zero-crossing information provided by the AC wave sampling resistor R, the MCU single-chip microcomputer controls the thyristors BCR1 and BCR2 to output a quasi-AC two-phase frequency of about 17Hz at the connection point of the 4-wire connection port (2), directly driving the main and auxiliary windings of the motor M to run at low speed and high torque. At this time, BCR3 connected to the phase-shifting capacitor C is not triggered, and the phase-shifting capacitor is equivalent to being disconnected. About half a minute later, the thyristors BCR1 and BCR3 change to full-wave triggering, and BCR2 is not triggered (that is, disconnected). It is equivalent to the main winding of the motor M being directly connected to the AC input, and the auxiliary winding of the motor M being connected in series with the phase-shifting capacitor C to the AC input. This is the normal operating mode of the original phase-shifting capacitor motor (full speed operation).

[0049] For circuit designs that continue to use relays or in high-power air conditioning applications, the switching of the conduction states of BCR3 and BCR1 can be replaced by relay contacts J1 and J2, see [link to relevant documentation]. Figure 5 Normally closed contacts J1 and J2 switch to a two-phase quasi-low-frequency AC (low-speed) mode (using BCR1 and BCR2) for soft-start buffering when power is off. After a few seconds of buffering, the relays are energized, and contacts J1 and J2 switch to a mode where the main winding of motor M is directly connected to the AC input, and the auxiliary winding of motor M is connected in series with the phase-shifting capacitor C to the AC input. This is the normal operating mode (full-speed operation) of the original phase-shifting capacitor motor. Although relays have poor reliability and their contacts are prone to burnout, they are considered to have no voltage drop during normal operation, eliminating the need for cumbersome heat sinks, and many manufacturers still use them.

[0050] In layman's terms, 2 combines the two-phase quasi-frequency conversion method of 1 with the normal operation mode of the original phase-shifting capacitor to improve it into a more practical drive module (with two speeds) to replace the original simple single-speed circuit with only one phase-shifting capacitor. This adds a soft start or idle speed operation state to the air conditioner compressor, and normalizes the frequent short-interval start and stop of the air conditioner compressor.

[0051] 3. Although the above-mentioned design 2 presents a compressor motor drive module that can improve the performance of fixed-frequency air conditioners, this is already standardized in the mature air conditioner production technology field (the production line will not be adjusted due to a small improvement). Therefore, it is necessary to propose a user-friendly and effective application method, and creatively explore supporting application solutions from basic to advanced levels to achieve unprecedented results (such as the air conditioner self-test function in application method B, which displays the severity of the problem numerically). The following are the application and promotion classification of peripheral supporting technical solutions for this invention.

[0052] This type of air conditioner compressor single-phase asynchronous motor drive module is applied. Figure 1 It can generally be divided into the following four forms:

[0053] Application Method A: The original fixed-frequency air conditioner main control board remains unchanged. The two compressor power supply lines in the original fixed-frequency air conditioner outdoor unit wiring are connected ( Figure 1 The AC input connection port (1) and the 4-wire connection port (2) are connected in the same way as the air conditioner compressor motor drive module described in 2. The communication control interface SIP4 (3) is not used, which can make the fixed frequency air conditioner compressor not afraid of frequent cooling start or stop operation (because the drive module has a few seconds of low speed buffer or idle speed working state smooth transition during the start and stop process). The following application method C and application method D are also this kind of scheme that does not change the original fixed frequency air conditioner main control board.

[0054] Application Method B: Add a time-based operating mode to the original fixed-frequency air conditioner's main control board (e.g., combined with temperature adjustment; when the temperature is set below the lowest setting, the compressor's continuous operating minutes are displayed: 15 indicates 15 minutes of continuous operation followed by 5 minutes of rest, continuously cycling; 10 indicates 10 minutes of continuous operation followed by 5 minutes of rest, continuously cycling; 5 indicates 5 minutes of continuous operation followed by 5 minutes of rest, continuously cycling), or add this time-based setting function to the air conditioner remote control (operation similar to the original air conditioner's timer function, e.g., compressor intermittent stop: 5 minutes). These settings or control commands are transmitted through (…). Figure 1 The communication control interface SIP4(3) notifies the driver module (this connection communication is further explained in 6. Technical Scheme C and 7. Design Scheme C below). The implementation technology includes a fixed-frequency air conditioner compressor idling state, so that the compressor can be frequently started and stopped in short intervals (the continuous rotation between short-interval cooling and idling state is to simulate the frequency conversion effect).

[0055] Previously, when the compressor stopped, the motor simply stopped turning. Now, depending on the needs, the motor can be allowed to run at a low speed. This is an innovative idle operating state for a fixed-frequency air conditioner compressor. It can reduce the compressor's operating capacity without changing the compressor pump structure or requiring a variable frequency drive for the motor. This can simulate an effect close to that of a variable frequency air conditioner and also allow for the design of a workflow to detect problems in the refrigeration system.

[0056] The workflow for detecting problems in the refrigeration system (taking refrigeration as an example only) is as follows: Idle operation is inserted at different time ratios, and the temperature sensor readings at specific temperature detection points of the fixed-frequency air conditioning system and the compressor operating current are used to detect problems in the refrigeration system (or the degree to which it deviates from normal operating conditions).

[0057] A typical fixed-frequency air conditioning system has the following specific temperature detection points: one each before and after the evaporator of the indoor unit (denoted as T1 and T2, to detect cooling performance), one at the air inlet of the indoor unit (denoted as T3, to detect ambient temperature), one on the capillary tube (denoted as T4, to detect the degree of blockage), and one near the outlet of the condenser of the outdoor unit (denoted as T5, to detect condenser heat dissipation). In addition, the compressor operating current (denoted as I) should also be considered.

[0058] The compressor's operating mode can be set according to time duration. In addition to the longer time setting (5-15 minutes) mentioned above, this also includes a test mode with a minimum 1-minute interval between operation and idle time. Let t represent the number of minutes of operation (inclusive) and t0 represent the number of minutes of idle time (inclusive). In the test mode, the compressor operates in a cycle of t minutes of normal operation + t0 minutes of idle operation.

[0059] Entering test mode (t+t0), T1, T2, T3, T4, T5, and I will be sent to the computer or mobile phone via wireless network.

[0060] For example, when the test mode (t+t0) = 1+0 (t0 = 0 means the compressor is running continuously and normally) and T3 = 30 (degrees), I should be 4 (A), but the test mode data shows I = about 3.5, which is too low. The operating current should be checked and refrigerant should be added.

[0061] If I = 4.5A, and the test mode is changed to t + t0 = 3 + 1, T1 = 27 (not much change, previously 26.5). The temperature of the evaporator temperature sensor does not change much, indicating that there are signs of capillary blockage or that too much refrigerant has been added.

[0062] If T1 = 28, and the test mode is changed to t + t0 = 5 + 1, then T1 = 27, indicating that T1 changes (inversely proportionally) with t (the cooling becomes worse), which should be due to poor heat dissipation and ventilation of the condenser. It needs to be cleaned or the ventilation problem needs to be checked.

[0063] Note that the test mode only provides the operating environment for detecting problems (providing T1-5 and I data); the judgment of the problem is left to the human. The self-test function described in section 8 below, however, is the automatic selection process for the air conditioner to find operational problems, providing a direct description of the problem.

[0064] The normal operating curves for T1, T2, T3, T4, T5, and I should be provided in the air conditioner manual (or displayed via a mobile app or computer program), and a correction function should be provided for users to input actual data, creating a more accurate basis for the self-test function.

[0065] In addition, for operating modes where the compressor is set to work or stop based on time duration (to simulate the effect of an inverter air conditioner), when the stop time is more than 5 minutes, it generally idles for 1 minute, then stops for more than 3 minutes, then idles for another minute for a warm-up, and then enters the normal operating time. It does not operate in idle mode for any period longer than 5 minutes because idle mode only involves low-speed operation with high torque (compared to capacitor phase-shifting operation), and is not energy-efficient (the speed is much lower than 1 / 3 of normal, and the current is only slightly lower than normal, but greater than 1 / 2 of the normal operating current because it is not an ideal two-phase low-frequency AC current). Therefore, idle mode is generally not used for continuous operation for more than 5 minutes.

[0066] There are mature technical solutions for MCU microcontrollers with ADC function to detect and record data, and transmit the data to a computer or mobile phone for display or printing via wired or wireless means. (For low-cost solutions that transmit data to a computer or mobile phone via wireless network, the ESP8266 is recommended. See invention patents CN202111098910.4 A method for IoT byte pass-through based on H5JS local programming and CN201911220992.8 A device and method for displaying electrocardiogram in a browser using UDP network protocol).

[0067] Note: The above method of diagnosing faults based on operating current and temperature differences from various temperature sensors only applies to simplified fixed-frequency air conditioners. Simplified fixed-frequency air conditioners do not use automatic expansion valves, and there is no short-circuit valve between the compressor's intake and exhaust pipes to regulate the load. These complex technologies make diagnosing faults based on operating current very complicated. Simplified fixed-frequency air conditioners can regulate the load by utilizing the compressor's idling state; idling for one minute causes no discomfort to humans (therefore, it can simulate an inverter air conditioner).

[0068] Judging air conditioner faults by analyzing operating current and temperature differences from various temperature sensors is easily achieved using an MCU microcontroller (without altering the air conditioner's mechanical structure). In contrast, diagnosing problems by air conditioner repair personnel through measuring refrigerant line pressure is cumbersome, dangerous (requiring climbing outside windows in high-rise buildings to connect the lines), and inaccurate, only becoming feasible when the problem is severe (requiring a repairman to come and inspect). The testing mode provided here presents the air conditioner's operating status to the user in quantitative values, allowing the user to assess the difference from optimal performance.

[0069] For fixed-frequency air conditioners that currently lack a testing mode, users can purchase a household electricity meter online (around 20 yuan), which includes functions for measuring current and power. Simply plug the power plug of the indoor unit of the air conditioner into the household electricity meter to see the current operating current of the air conditioner. Users can also purchase one or two digital display temperature measurement modules with flexible lead temperature sensor probes online and install them at one or two temperature detection points on the evaporator vents of the indoor unit of the air conditioner to observe temperature changes.

[0070] Application Method C: The original fixed-frequency air conditioner main control board and remote control remain unchanged. An external timed infrared remote control device is added. This device records the button codes of two air conditioner remote controls (commonly known as a learning remote control). When the device records the lowest cooling temperature (ensuring cooling starts; ensure appropriate fan speed and direction are set beforehand) and no cooling (ensuring appropriate fan speed and direction are set beforehand) (referred to as the two recorded air conditioner states), it will periodically send infrared codes for these two states (including fan speed and direction). The timer can also be set at 5-minute or 10-minute intervals. This external timed infrared remote control can be rechargeable or plug-in. It is plugged into the air conditioner and the infrared transmitter is rotated to point at the indoor unit, allowing the air conditioner to continuously receive code control from the device and cycle through the two recorded air conditioner states (including short-interval cooling and idling to simulate inverter effects). This is actually a specific application of solution A (the original fixed-frequency air conditioner main control board is not modified).

[0071] Application method D: To broaden the application flexibility of this single-phase asynchronous motor drive module for air conditioner compressors, this drive module ( Figure 1 The control functions of the module itself can also be increased as follows (Note: The driver modules targeted by the above application methods A and C are of the same basic type, namely, those described in 2. Here, we propose to further increase their functions):

[0072] a、( Figure 1 The instantaneous power-off of the AC input connection port (1) in the middle is used as a control command: if no power-off occurs within 2 seconds of power-on, it will run continuously at full speed after normal soft start until power-off (the original fixed frequency air conditioner main control board does not need any modification); if there are several power-offs of 0.5 seconds within 2 seconds of power-on, it will be used as a control command. For example, one power-off means running for 5 minutes and stopping for 5 minutes in a cycle, two power-offs mean running for 10 minutes and stopping for 5 minutes in a cycle, and three power-offs mean running for 5 minutes and stopping for 10 minutes in a cycle. (For details of the power-off control implementation method, please refer to: Invention Patent 201611208010.X A single-chip microcomputer power switch and shifting module and its control method. In fact, this technology has long been used in lighting fixtures for multi-channel switching, commonly known as a switch segment control module. In the early days, it was implemented using general CMOS digital circuits. At present, this power-off control is widely used in LED lights with dual-color dimming).

[0073] b. Connect to (using a 3-core or 4-core long connecting cable) Figure 1 The communication control interface SIP4(3) is controlled by a combination of logic levels.

[0074] c. Connect to (using a 3-core or 4-core long twisted pair cable) Figure 1The communication control interface SIP4(3) uses RS serial communication. For complex control, including setting (time) parameters, the parameters need to be recorded in the Flash EEPROM of the MCU microcontroller and not lost when the power is off. Therefore, this RS serial communication method is used (the specific command communication format can be agreed upon according to the functional requirements).

[0075] d. Use a wireless module (e.g., NRF24L01+) to connect to an MCU microcontroller (STC15 series or STC8G series) via an SPI serial interface to wirelessly set the low-speed start delay or high / low speed operation timed cycle rules for the air conditioner compressor. The original fixed-frequency air conditioner main control board remains unchanged (the original infrared remote control is also unchanged). Instead, a wireless module (NRF24L01+) is added to the driver module to create a driver module with wireless remote control functionality. The matching wireless remote control box controls the driver module with wireless remote control functionality installed in the outdoor unit of the air conditioner. That is, the original infrared remote control controls the indoor unit of the air conditioner, while the added wireless remote control box controls the outdoor unit from the window. The MCU on the wireless remote control driver module has a function to retain information even when power is off, so the wireless remote control box is not used every time, but only when settings need to be changed.

[0076] Note: The above application methods A, C, and Dd all do not change the existing fixed-frequency air conditioner, but use supplementary drive modules and wireless remote control to realize the soft start and idle speed operation state of the fixed-frequency air conditioner to simulate the effect of frequency conversion, or add a preset start-stop time interval operation mode to the compressor.

[0077] 4. This embodiment also provides a fan speed control module based on a two-phase quasi-frequency conversion method using thyristors (adding two-phase quasi-low-frequency AC drive to a single-phase asynchronous motor for low-speed operation on the basis of the original full-speed operation formed by the phase-shifting capacitor, thus realizing a speed control module with two speed levels). Its structural features are (emphasizing simplicity and ease of use, and convenient installation). The speed control module is a circuit board the size of a charging head, which may have a plastic shell. It is installed inside the fan base. In addition to the thyristor control circuit described in 1 (power supply section, thyristors BCR1, BCR2, BCR3, MCU microcontroller, AC wave sampling resistor R), the circuit board also includes (…). Figure 1 The AC input connection port (1) and the 4-wire connection port (2) are connected. The AC input connection port (1) is connected to the 220V AC input power line; the connection points in the 4-wire connection port (2) are the three T2 output terminals of the thyristors BCR1, BCR2, and BCR3 and one AC terminal that is collinear with one pole in the AC input connection port (1), which are connected in sequence to the main winding, auxiliary winding, phase-shifting capacitor, and the common terminal of the main and auxiliary windings of the fan motor.

[0078] The functional features are as follows: the AC power supply of the AC input connection port (1) has an instantaneous power-off function as a control command: whenever the power is cut off for about 0.5 seconds (the button is pressed again after power is cut off), the control command is executed, switching sequentially from low speed to high speed. The medium speed is optional; if it is present, it is simulated by an automatic timed cycle from low speed to high speed (e.g., low speed for 6 seconds, high speed for 5 seconds cycle). Fans constructed with this type of fan speed control module only require a self-locking button switch for both switching and speed control (simple, reliable, beautiful, and low cost).

[0079] When the AC input is connected to port (1), the MCU microcontroller controls the thyristors BCR1 and BCR2 to output a quasi-AC two-phase current at a frequency of approximately 17Hz at the connection point of the 4-wire connection port (2), directly driving the main and auxiliary windings of the motor to run at low speed. At this time, BCR3 connected to the phase-shifting capacitor C is not triggered, and the phase-shifting capacitor C is equivalent to being disconnected. When switching to the high-speed mode (the button is turned off and then pressed again), the thyristors BCR1 and BCR3 change to full-wave triggering, and BCR2 is not triggered (that is, disconnected). This means that the main winding of the motor is directly connected to the AC input, and the phase-shifting capacitor C of the auxiliary winding of the motor is also connected to the AC input. This is the normal full-speed operation of the original phase-shifting capacitor motor.

[0080] In layman's terms, 4 is the same as 2, combining the method in 1 with the normal operation mode of the original phase-shifting capacitor to create a more practical drive module (with two speeds), replacing the original simple single-speed circuit with only a phase-shifting capacitor. This enables two speeds for a single-speed, single-phase asynchronous motor fan. Also, like 2, a relay can be used to replace BCR3.

[0081] In applications where non-zero-crossing triggering of AC power is not a concern, the phase-shifting capacitor C and BCR3 in the high-speed range can be omitted and replaced by BCR2, which triggers at 5 milliseconds (90 degrees) per wave (but its operating efficiency is lower than that of the phase-shifting capacitor and is only used in low-end, inexpensive products).

[0082] For details on the implementation method of power-off control, please refer to: Invention Patent 201611208010.X, A Microcontroller Power Switch and Gear Shifting Module and Its Control Method. This technology has actually been used in lighting fixtures for multi-channel switching, commonly known as a switch segmentation control module, which was initially implemented using general-purpose CMOS digital circuits. Currently, this type of power-off control is widely used in dual-color LED lights.

[0083] 5. A simplified version (as described in 1) of a single-phase 16.67Hz quasi-AC output module with only one output channel can be packaged in a plastic box as a single-phase asynchronous motor / fan low-wind power adapter (or fan speed reducer plug). This allows for the unmodified low-wind function of AC fans (either phase-shifting capacitor type or AC motor with a short-circuited copper ring on one side of the stator). The effect is better than commercially available SCR speed controllers because it is noiseless and features zero-crossing triggering. Figure 2 One of the 16.67Hz quasi-AC outputs is encapsulated in a plastic box as a plug-in.

[0084] The practical background is that air conditioning has become mainstream, and electric fans have become obsolete. However, a new use of home air conditioning is to use a low-powered electric fan to slowly introduce cool air from other air-conditioned rooms into the sleeping room, making the sleeping room more comfortable. Therefore, the low-powered electric fan needs to have relatively large blades but a very slow rotation speed. Currently, there are no such affordable low-powered fans (priced under 50 yuan) on the market, so a regular classic AC fan with a low-powered fan adapter can solve the problem.

[0085] The BCR thyristor control circuit mentioned in the thyristor quasi-frequency conversion method described in 6.1 is a basic principle structure. For the specific applications mentioned above, several more economical and applicable preferred technical solutions need to be designed based on the type of the corresponding air conditioner main control board, the supply situation of components, or the cost performance of components.

[0086] Regarding the BCR thyristor control circuit described in section 1, the following technical solutions exist:

[0087] Technical Solution A: Connect the positive terminal of the regulated output, one terminal of the AC power supply, and the T1 terminal of the BCR thyristor together (see...). Figure 2 The solution on the top left is more reasonable (such as widening the selection range of thyristor triggering performance, because it does not need to use the G+T2- triggering method, and the MCU microcontroller has a larger drive current for pull-down).

[0088] Technical Solution B: When using a non-isolated high-efficiency monolithic IC power supply, the typical regulated output is a scheme where the negative terminal, one terminal of the AC power supply, and the T1 terminal of the BCR thyristor are connected together (referred to as the regulated output method). Directly driving the high-power thyristor with a microcontroller can cause some problems (the BCR triggering method is G+T2-, and some thyristors, such as the BTA16-800, require a trigger current of over 50mA. High current at the microcontroller port can also cause other issues). Therefore, a capacitor-stored transistor driving thyristor mode is used (see...). Figure 8 The connection structure is as follows:

[0089] Connect the negative terminal of the regulated output, one terminal of the AC power supply, and the T1 terminal of the BCR thyristor together. Then connect the negative terminal of the MCU power supply, the negative terminal of the filter capacitor C2, and the emitter of the transistor Tr1. The T2 terminal of the BCR thyristor is the output terminal. Connect the positive terminal of the regulated output to the positive terminal of the MCU power supply, one end of the charging resistor R5, and the positive terminal of the filter capacitor C2 together. Connect the collector of the transistor Tr1 to the other end of the charging resistor R5 and one end of the energy storage capacitor C5 together. Connect the other end of the energy storage capacitor C5 to one end of the current limiting resistor R6. Connect the other end of the current limiting resistor R6 to the trigger terminal G of the BCR thyristor. Connect the base of the transistor Tr1 in series with a resistor to the output port of the MCU.

[0090] Technical Solution C: When this non-isolated high-voltage MCU needs to be connected to other low-voltage control components (which poses serious safety issues) or to adapt to the economical power supply mode of capacitor step-down bridge rectification, the control circuit of the BCR thyristor can adopt optocoupler isolation or magnetic core transformer isolation to drive the thyristor.

[0091] The optocoupler isolation connection structure is as follows (see Figure 2 (Top right): Connect the T1 terminal of the BCR (Silicon Controlled Rectifier) ​​to one end of the AC power supply. The T2 terminal of the BCR is the output terminal, which is also connected to one end of the output of the opto-isolated SSR (Series Independent Transistor). The other end of the opto-isolated SSR output is connected in series with resistor R2 to the trigger terminal G of the BCR. The trigger terminal G of the BCR is also connected to resistor R1 to the T1 terminal of the BCR. The positive input terminal of the opto-isolated SSR is connected to the positive terminal of the microcontroller's power supply. The negative input terminal of the opto-isolated SSR is connected in series with resistor R1 to the output port of the microcontroller.

[0092] The isolation connection structure of the magnetic core transformer is as follows: Connect the T1 terminal of the BCR thyristor to one end of the AC power supply. The T2 terminal of the BCR thyristor is the output terminal. Connect one end of the secondary winding of the magnetic core transformer to the T1 terminal of the BCR thyristor. Connect the other end of the secondary winding of the isolation transformer to the trigger terminal G of the thyristor BCR. Connect one end of the primary winding of the magnetic core transformer to the positive terminal of the microcontroller power supply. Connect the other end of the primary winding of the magnetic core transformer in series with a resistor to the output port of the microcontroller.

[0093] This isolated drive mode for driving thyristors does not restrict the power supply connection of the microcontroller, as long as it is suitable for the microcontroller's operation. It is particularly suitable for microcontrollers powered by commonly used AC isolated power supply modules to achieve safe external communication connections (commonly known as "cold board"), or for economical power supply modes using capacitor-based step-down bridge rectification (see...). Figure 2 (Top right)

[0094] Note: Optocoupler-isolated SSR devices are themselves optocoupler thyristors, only with lower power.

[0095] Transformer triggering (with a well-matched transformer ratio) can achieve a smaller drive current. The secondary positive and negative waves also have a supplementary triggering function (i.e., if the positive half-wave fails to trigger conduction, the subsequent negative half-wave will trigger it), making the triggering more reliable, but it is costly and bulky.

[0096] The connection and communication with the fixed-frequency air conditioner main control board via the SIP4(3) port in application method B above requires this isolated drive thyristor mode. However, it should be noted that when the fixed-frequency air conditioner main control board is connected via the SIP4(3) port, a 5V working voltage is usually provided at the positive and negative connection points of the SIP4(3) port, so the drive module no longer needs a power supply section.

[0097] This article clarifies the isolated and non-isolated control methods of the BCR (Silicon Controlled Rectifier) ​​on the output terminal of a microcontroller. In this text, they will all be referred to as BCRs. The T1 terminal is connected to one end of the AC power supply, and the T2 terminal is the output terminal. Furthermore, there are multiple such BCRs, such as BCR1, BCR2, BCR3, etc. (see...) Figure 1 Their T1 terminals are all connected to one end of the AC power supply, and the T2 terminal is the output terminal of each circuit. The two-phase quasi-frequency AC output mentioned in 1 is the first circuit output of the first BCR1 and the second circuit output of the second BCR2 (the specific isolation and non-isolation connections between the microcontroller and the thyristor will not be detailed here).

[0098] 7. With the widespread availability of monolithic switching power supply constant current chips for LED lights, as well as monolithic AC-DC switching power supply ICs or high-voltage step-down DC-DC chips, these convenient (extremely simple peripheral circuitry, no IC power supply auxiliary winding) high-performance switching power supply chips are perfectly suited for the power supply section of the aforementioned thyristor quasi-frequency conversion method. Design schemes for several typical cases are presented below.

[0099] Design Scheme A employs a single-chip AC-DC switching power supply without an IC power supply auxiliary winding, using an inductor to construct a non-isolated regulated output. This provides power to the microcontroller driving the thyristor, achieving the solution described in Scheme A: connecting the positive terminal of the regulated output, one terminal of the AC power supply (which is also the high-voltage positive terminal after rectification and filtering), and the T1 terminal of the BCR thyristor together (referred to as the regulated output method). The key connections are as follows ( Figure 3The following connections are made: AC terminal (one pole), positive terminal of high-voltage half-wave rectifier filter electrolytic capacitor C1, negative terminal of flyback freewheeling diode D5, positive terminal of regulated output filter capacitor C2, one end of regulated output sampling resistor R5, positive terminal of MCU power supply, and T1 terminal of SCR BCR are connected together; one end of high-frequency buck inductor L, negative terminal of regulated output filter capacitor C2, positive terminal of Zener diode DW, and negative terminal of MCU power supply are connected together; the switching transistor D terminal of the switching power supply IC is connected to the other end of high-frequency buck inductor L and positive terminal of flyback freewheeling diode D5; the feedback control Fb terminal of the switching power supply IC is connected to the positive terminal of the optocoupler OC output side; the negative terminal of the optocoupler OC output side and the switching power supply IC... The ground terminal, the positive terminal of the high-voltage rectifier diode D0, and the negative terminal of the high-voltage half-wave rectifier filter electrolytic capacitor C1 are connected together. The AC terminal of the other AC terminal, one end of the current-limiting resistor r0 (power-on surge protection), and one end of the AC wave sampling resistor R are connected together, which is also the AC common output terminal. The other end of the AC wave sampling resistor R is connected to the input port of the microcontroller MCU, and the other end of the current-limiting resistor r0 is connected to the negative terminal of the high-voltage rectifier diode D0. The series resistor R1 of the microcontroller MCU output port is connected to the gate (G) of the silicon controlled rectifier (SCR). The negative terminal of the Zener diode DW is connected to the negative terminal of the LED on the input side of the optocoupler OC, and the positive terminal of the LED on the input side of the optocoupler OC is connected to the other end of the regulated output sampling resistor R5. Using an inductor instead of a transformer to form a non-isolated regulated output has the advantages of low cost, high reliability, and small size. The scheme where the positive terminal of the regulated output is connected to one of the AC terminals (the regulated output method) requires an optocoupler OC for regulated sampling feedback. IC chips commonly used in isolated power supplies (the type with self-powered operation and no auxiliary winding) can also be used as non-isolated regulated power supply IC chips here, such as CSC7203 and DK1203.

[0100] Design scheme B employs a high-voltage step-down DC-DC chip and uses an inductor to construct a non-isolated regulated output, providing power to the microcontroller driving the thyristor, thus achieving the scheme described in technical scheme B: connecting the negative terminal of the regulated output, one terminal of the AC power supply (which is also the high-voltage negative terminal after rectification and filtering), and the T1 terminal of the BCR thyristor together (referred to as the regulated output method). The key connections are as follows ( Figure 4The AC terminal of one power supply is connected to the negative terminal of the high-voltage half-wave rectifier filter electrolytic capacitor C1, the positive terminal of the flyback freewheeling diode D5, the negative terminal of the voltage regulator filter capacitor C2, the negative terminal of the MCU power supply, and the T1 terminal of the SCR BCR. One end of the high-frequency step-down inductor L, the positive terminal of the voltage regulator filter capacitor C2, the positive terminal of the voltage regulator feedback diode D6, and the positive terminal of the MCU power supply are connected together. The D terminal of the switching transistor of the switching power supply IC, the positive terminal of the high-voltage half-wave rectifier filter electrolytic capacitor C1, and the negative terminal of the high-voltage rectifier diode D0 are connected together. The AC terminal of the other power supply, one end of the current-limiting resistor r0 (for power-on surge protection), and one end of the AC wave sampling resistor R are connected together, which is also the common AC output terminal. The other end of the AC wave sampling resistor R is connected to the MCU. The input port of U is connected to the positive terminal of the high-voltage rectifier diode D0 via the other end of the current-limiting resistor r0. The output port of the microcontroller MCU is connected to the gate of the silicon controlled rectifier BCR via the series resistor R1. The negative terminal of the Zener feedback diode D6, the positive terminal of the power supply IC, the positive terminal of the power supply filter capacitor C3 of the power supply IC, and one end of the regulated output voltage sampling resistor R7 are connected together. The other end of the regulated output voltage sampling resistor R7, one end of the regulated output voltage sampling divider resistor R6, and the feedback control Fb terminal of the power supply IC are connected together. The negative terminal of the power supply filter capacitor C3 of the power supply IC, the other end of the regulated output voltage sampling divider resistor R6, the negative terminal of the power supply IC, the other end of the high-frequency step-down inductor L, and the negative terminal of the flyback freewheeling diode D5 are connected together. This scheme, in which the negative terminal of the regulated output is connected to one terminal of the AC power supply and the T1 terminal of the BCR thyristor (referred to as the regulated output method), may cause some problems when directly driving a microcontroller with a high-power thyristor (the negative half-wave may not trigger or the requirement of a large trigger current may cause other problems). It is possible to use the capacitor energy storage transistor driving thyristor mode of technical scheme B in 6. or the optocoupler isolation driving thyristor mode of technical scheme C in 6. (Since optocoupler isolation is used, it is also feasible to connect the T1 terminal of the BCR thyristor to the other terminal of the AC power supply above.) The advantage of the regulated output method is that it achieves voltage regulation without optocoupler OC and the power chip can be self-powered. Therefore, there is a particularly rich variety of such high-voltage buck DC-DC chips, such as: LNK304, XD308H, SM7012, VIPer12A, BP2525x, KP35026VGA, WD5205, LP2179, SX3701 (the first four are typical, and the latter five are optimized to be simpler. In fact, any pull-up Fb type general AC-DC switching power supply single-chip IC can be used here).

[0101] The above typical connection (output mode under voltage regulation, belonging to BUCK output structure) can be slightly adjusted to become a BUCK-BOOST output structure, thus realizing the scheme described in Design Scheme A where the positive terminal of the regulated output is connected to one terminal of the AC power supply and the T1 terminal of the BCR thyristor. The adjusted connection is as follows: the AC terminal, the negative terminal of the high-voltage half-wave rectifier filter electrolytic capacitor C1, one end of the high-frequency step-down inductor L, the positive terminal of the regulated output filter capacitor C2, the positive terminal of the MCU power supply, and the T1 terminal of the thyristor BCR are connected together; the positive terminal of the flyback freewheeling diode D5, the negative terminal of the regulated output filter capacitor C2, and the negative terminal of the MCU power supply are connected together. In this BUCK-BOOST output structure, the connection point where the AC terminal and the T1 terminal of the BCR thyristor are connected (which is also the high-voltage negative terminal after rectification and filtering) becomes the positive terminal of the regulated output; the voltage generated by the high-frequency inductor L during flyback, which is more negative than the high-voltage negative terminal after rectification and filtering (i.e., the positive terminal of the regulated output), is used as the negative terminal of the regulated output. This achieves the connection between the positive terminal of the regulated output, the AC power supply, and the T1 terminal of the BCR thyristor, as described in Design Scheme A (eliminating the need for the capacitor-driven thyristor mode in Scheme B, the optocoupler-isolated thyristor mode in Scheme C, and the optocoupler OC in Scheme A). This (such a component-saving preferred solution) is atypical because its regulated output is solely generated by the energy storage and retracement of the high-frequency inductor L, resulting in slightly lower efficiency or a slightly larger requirement for the high-frequency inductor L compared to typical DC-DC BUCK regulation. However, since the regulated power supply here is used for driving the thyristor with an MCU, the efficiency issue is negligible, and there is no need to increase the size of the high-frequency inductor L. A complete circuit diagram can be found in SM7055.pdf.

[0102] Design Scheme C: For typical isolated AC regulated power supplies or readily available AC-DC regulated power supply modules, either the positive or negative terminal of the 5V DC output can be connected to one terminal of the AC power supply and the T1 terminal of the BCR thyristor. The positive and negative terminals of the 5V DC output are connected to the positive and negative terminals of the microcontroller's (MCU) power supply, respectively. The output port of the MCU is connected in series with resistor R1 to the gate (G) terminal of the BCR thyristor. The other AC terminal, which is also the common AC output, is connected to one end of the AC wave sampling resistor R, and the other end of the AC wave sampling resistor R is connected to the input port of the MCU. Since typical AC regulated power supplies are isolated, either the positive or negative terminal of the regulated output can be connected to one terminal of the AC power supply. However, for better thyristor triggering (or for easier MCU pull-down), it is recommended to connect the positive terminal to one terminal of the AC power supply and the T1 terminal of the BCR thyristor (see...). Figure 2 (Top left)

[0103] The targeted application of the isolated AC-DC regulated power supply module and the isolated thyristor drive mode is that the microcontroller does not carry high voltage (commonly known as "cold baseboard"), so as to realize a safe microcontroller external communication connection. The above-mentioned application method B, which connects to the fixed frequency air conditioner main control board through the SIP4 (3) port, requires this mode.

[0104] Note that the positive and negative terminals of this dual-isolation AC-DC regulated power supply module are not directly connected to the L and N input terminals of the 220V AC power supply. The usual connection method is to connect the negative terminal of the regulated output to the negative terminal of the microcontroller's power supply as a signal ground, which is then connected to the signal ground of the air conditioner's main control board (which is the grounding wire in the national standard single-phase three-wire AC power supply). In this case, one end of the AC wave sampling resistor R must be connected to the live wire L terminal of the AC power supply.

[0105] Design scheme D, economical power supply mode with capacitor step-down bridge rectification ( Figure 2 (Top right): The AC terminal of the other AC terminal is connected in series with an anti-power-on surge current-limiting resistor r0 and a step-down capacitor C0 to the input terminal of the bridge rectifier D4. The other end of the bridge rectifier D4 input is connected to one terminal of the AC power supply and the T1 terminal of the BCR thyristor. An overvoltage protector Vz is then connected in parallel to these two input terminals of the bridge rectifier D4. The positive output terminal of the bridge rectifier D4 is connected to the positive terminal of the filter capacitor C1 and the input terminal of the linear regulator LDO. The negative output terminal of the bridge rectifier D4 is connected to the negative terminal of the filter capacitor C1, the ground terminal of the linear regulator LDO, the negative terminal of the filter capacitor C2, and the negative terminal of the microcontroller MCU power supply. The output terminal of the linear regulator LDO is connected to the positive terminal of the filter capacitor C2 and the positive terminal of the microcontroller MCU power supply. The AC terminal of the other AC terminal, which is also the AC common output terminal, is connected in series with an AC wave sampling resistor R to the input port of the microcontroller MCU. The microcontroller MCU uses the optocoupler isolation driving thyristor BCR mode described in technical solution C. This capacitor step-down scheme has a lower cost and is more advantageous in inexpensive fan-type products.

[0106] In all design schemes A, B, C, and D, it is mentioned that an AC input pole is connected in series with a current-limiting resistor r0 to resist power-on surges. This is because the drive module has the function of momentarily cutting off power to control commands when the AC input is turned on. Therefore, it must be able to adapt to multiple momentary power-off operations when power is turned on to prevent the high-voltage filter capacitor or AC step-down capacitor from arcing due to voltage changes or the components from being burned out by the power-on surge current.

[0107] Regarding control commands for momentary power outages, it's important to note that for devices that the microcontroller cannot shut down (typically, the load resistor and voltage sampling resistors at the output of a switching power supply's regulated circuit are power-consuming devices that cannot be turned off), many LDO regulated outputs are high-impedance and do not consume power. Figure 2The economical power supply mode of the capacitor-driven buck bridge rectifier in the upper right corner uses an LDO (Low-Drop Regulated Output). The microcontroller power supply requires diode unidirectional conduction isolation. For the regulated output mode (see...),... Figure 6 For a more detailed explanation, see 201611208010.X (A Microcontroller Power Switch and Gear Shifting Module and Its Control Method). The connection method is as follows: the positive terminal of the regulated power supply is connected to the positive terminal of the diode, the negative terminal of the diode is connected to the positive terminal of the microcontroller power supply, the positive terminal of the microcontroller power supply is simultaneously connected to one end of a large-capacity filter capacitor, and the other end of the large-capacity filter capacitor is connected to the negative terminal ground of the microcontroller power supply. The large-capacity filter capacitor also serves as a short-time power supply for power-off control. For the regulated output method, the positive terminal of the regulated output is connected to one terminal of the AC power supply and the T1 terminal of the BCR thyristor, and a unidirectional conducting isolation diode is connected in series with the negative terminal of the regulated output (see...). Figure 7 ).

[0108] 8. The test mode described in section 3. Application Method B above can be further improved into a self-test function for fixed-frequency air conditioners, supplementing the commonly used standard functions of fixed-frequency air conditioners. The self-test process is initiated by pressing a button or operating the remote control. Based on the several temperature sensors and compressor operating current set in the existing fixed-frequency air conditioner, it automatically selects a specific time interval for working / idling operation. It judges the air conditioner's operating problems or faults based on the temperature difference and current changes of each temperature sensor caused by changes in operating status, and displays the self-test results digitally on the display screen of the indoor unit of the air conditioner or sends them to a computer and / or mobile phone via wireless network.

[0109] The air conditioner indoor unit display screen originally only had two digits "88" (used only for temperature setting). To indicate air conditioner problems or malfunctions, the following notation can be used:

[0110] 00-09: Basically no problem, only minor differences, the degree is represented by 0-9.

[0111] E0-E9: There is a problem; the type is represented by 0-9.

[0112] F0-F9: Fluorine deficiency or excessive fluorine addition, the degree is indicated by 0-9.

[0113] H0-H9: Capillary blockage or excessive refrigerant addition, the degree is indicated by 0-9.

[0114] P0-P9: Compressor, motor, or capacitor problems, categorized by 0-9.

[0115] The self-test results, transmitted wirelessly to a computer or mobile phone, are presented in text rather than simple numerical representations, making them highly practical. Regular self-tests allow for targeted maintenance or repair requests (instead of waiting until the air conditioner stops cooling), reducing air conditioner repair costs, especially avoiding unnecessary expenses and preventing the unfortunate situation where paid repairs lead to further damage. This shifts the mindset from simply ensuring the air conditioner cools to understanding how far it is from its optimal operating condition.

[0116] 9. The thyristor quasi-frequency conversion method and the single-phase asynchronous motor drive module in the air conditioner fan described in 1-7 are composed of many parts such as microcontroller, thyristor control circuit, and power supply circuit. Once the conditions are ripe, each circuit can be integrated as much as possible with process-specific integrated circuit chips or modules (i.e., one or several dedicated supporting ICs or modules).

[0117] Note: The MCU microcontrollers, SCR control circuits, and power supplies mentioned in 1, 6, and 7 are all principle-based structural components (or small-batch trial products, mainly for illustrating the principles) during the R&D stage. Once they gain market acceptance, mass production will no longer be possible to program each MCU microcontroller individually. It is necessary to integrate process-specific integrated circuit chips or modules according to the rationality of the production process, at least in batches using the OTP process (one-time programming).

Claims

1. A two-phase quasi-frequency conversion method composed of thyristors, the control circuit of the thyristors comprising an MCU single-chip microcomputer, a BCR thyristor and a power supply part, characterized in that, The MCU single-chip microcomputer selectively triggers the silicon-controlled rectifier to output according to the positive and negative alternating wave sequence of the alternating current, so that the frequency of the output alternating current wave is reduced to 1 / 3 of the original, and the positive and negative waves are still balanced, which is quasi-alternating current with a frequency of 16.67 Hz; The selective triggering of the silicon-controlled rectifier output rule is that, from the positive wave triggering output, the next negative and positive waves do not trigger and output, and the next negative wave triggers the output; that is, every time, one wave is output after an interval of two waves, the output wave is still alternating, the frequency is 1 / 3 of the original, the frequency is reduced, and the first quasi-alternating current with a frequency of 16.67 Hz is obtained; The second quasi-alternating current is output according to the same rule, and the phase difference between the first quasi-alternating current and the second quasi-alternating current is one 10mS wave, so that the first quasi-alternating current and the second quasi-alternating current form two-phase quasi-alternating current for driving a single-phase asynchronous motor, which is referred to as two-phase quasi-variable frequency alternating current or two-phase quasi-variable frequency method; The control circuit connection scheme of the silicon-controlled rectifier is that the power supply part is a 220V alternating current voltage reduction and stabilization output, a low-voltage stable direct current is used to supply power to the MCU single-chip microcomputer, the output port of the MCU single-chip microcomputer is connected to the trigger electrode G of the BCR silicon-controlled rectifier, one pole of the single-phase alternating current is connected to the T1 pole of the BCR silicon-controlled rectifier, the T2 pole of the BCR silicon-controlled rectifier is an output end, the other pole of the quasi-alternating current output is in line with the other pole of the single-phase alternating current input, and is also a common end of the two-phase quasi-alternating current output; the two-phase quasi-alternating current output is the output of the first silicon-controlled rectifier BCR1 and the output of the second silicon-controlled rectifier BCR2; The MCU single-chip microcomputer has an input port connected to one end of the alternating current supply through a high-resistance resistor R to obtain the zero-crossing information of the alternating current waveform, which is referred to as an alternating current wave sampling resistor R.

2. The two-phase quasi-analog frequency variation method according to claim 1, characterized in that, A single-phase asynchronous motor fan breeze power adapter can also be realized, which converts the input ordinary 50Hz alternating current into 16.67Hz single-phase quasi-alternating current to directly drive the fan single-phase asynchronous motor to run at low speed and realize breeze; the fan breeze power adapter is a power adapter with a plug and a socket part, the plug part is inserted into the alternating current power supply, and the socket part is inserted into the power cord plug of the alternating current fan; the socket part outputs a single-phase quasi-alternating current with a frequency of 16.67Hz.

3. The two-phase quasi-analog frequency variation method according to claim 1, characterized by, According to different application environments or component differences, the following technical solutions can be used for the silicon-controlled rectifier control circuit: Technical scheme A, when it is necessary to reduce the BCR silicon-controlled rectifier trigger current and the single-chip microcomputer port driving current, the control circuit of the BCR silicon-controlled rectifier adopts a connection scheme in which the positive pole of the voltage stabilizing output, one pole of the alternating current, and the T1 pole of the BCR silicon-controlled rectifier are connected together; Technical scheme B, when a non-isolated high-efficiency single IC power supply is used, the control circuit of the BCR silicon-controlled rectifier adopts a capacitor energy storage transistor-driven silicon-controlled rectifier mode, and the specific structure is as follows: The negative electrode of the voltage stabilizing output, one pole of the alternating current and the T1 pole of the BCR thyristor are connected together, and then the negative electrode of the MCU single-chip microcomputer power supply, the negative electrode of the filter capacitor C2 and the emitter electrode of the transistor Tr1 are connected together, the T2 pole of the BCR thyristor is an output terminal, the positive electrode of the voltage stabilizing output, the positive electrode of the MCU single-chip microcomputer power supply and one end of the charging resistor R5, and the positive electrode of the filter capacitor C2 are connected together, the collector electrode of the transistor Tr1 and the other end of the charging resistor R5 and one end of the energy storage capacitor C5 are connected together, the other end of the energy storage capacitor C5 is connected to one end of the current-limiting resistor R6, the other end of the current-limiting resistor R6 is connected to the trigger pole G of the BCR thyristor, and the base electrode of the transistor Tr1 is connected to the output port of the single-chip microcomputer in series with a resistor. When there is a safety problem in the connection of the MCU single-chip microcomputer with the strong and weak electric control components or the power supply mode of the capacitor voltage reduction bridge rectifier needs to be adapted, the control circuit of the BCR thyristor adopts a light-coupled isolation or a magnetic core transformer isolation driving thyristor mode. The T1 pole of the BCR thyristor is connected to one end of the alternating current power supply, the T2 pole of the BCR thyristor is an output terminal, the T2 end is connected to one end of the light isolation SSR output, the other end of the light isolation SSR output is connected to the trigger pole G of the BCR thyristor in series with a resistor r2, the trigger pole G of the BCR is connected to the T1 pole of the BCR thyristor through the resistor r1, the positive electrode of the input end of the light isolation SSR is connected to the positive electrode of the single-chip microcomputer power supply, and the negative electrode of the input end of the light isolation SSR is connected to the output port of the single-chip microcomputer in series with a resistor R1. The magnetic core transformer isolation feature is that a magnetic core isolation transformer is added at the connection of the MCU single-chip microcomputer and the BCR thyristor, and the specific structure is as follows: The T1 pole of the BCR thyristor is connected to one end of the alternating current power supply, the T2 pole of the BCR thyristor is an output terminal, one end of the secondary side of the magnetic core transformer is connected to the T1 pole of the BCR thyristor, the other end of the secondary side of the isolation transformer is connected to the trigger pole G of the BCR thyristor, one end of the primary side of the magnetic core transformer is connected to the positive electrode of the single-chip microcomputer power supply, and the other end of the primary side of the magnetic core transformer is connected to the output port of the single-chip microcomputer in series with a resistor. The above-mentioned isolation and non-isolation single-chip microcomputer output end control BCR thyristor mode is collectively referred to as BCR, the T1 pole of which is connected to one end of the alternating current power supply, the T2 pole of which is an output terminal, and such a BCR has three paths, including BCR1, BCR2 and BCR3, the T1 poles of which are all connected to one end of the alternating current power supply, and the T2 poles of which are output terminals of the respective paths; the two-phase quasi-variable frequency alternating current output is output by the first BCR1 and the second BCR2.

4. The two-phase quasi-analog frequency variation method according to claim 1, characterized by, The design scheme of the power supply part comprises: The design scheme A adopts an AC-DC step-down switching power IC, and uses an inductor to form a non-isolated voltage stabilizing output, to provide a working power supply for a single-chip microcomputer driven thyristor, to realize a scheme that a positive electrode of the voltage stabilizing output, one pole of an alternating current and a T1 pole of a BCR thyristor are connected together, and the connection structure is as follows: one pole AC of the alternating current, a positive electrode of a high-voltage half-wave rectification filter electrolytic capacitor C1, a negative end of a reverse-continuation diode D5, a positive end of a voltage stabilizing output filter capacitor C2, one end of a voltage stabilizing output sampling resistor R5, a positive electrode of a single-chip microcomputer MCU power supply, and a T1 pole of a thyristor BCR are connected together; one end of a high-frequency step-down inductor L, a negative end of the voltage stabilizing output filter capacitor C2, a positive end of a voltage stabilizing tube DW, and a negative electrode of the single-chip microcomputer MCU power supply are connected together; a switch tube D end of the switching power IC is connected with the other end of the high-frequency step-down inductor L and a positive end of the reverse-continuation diode D5, a feedback control Fb end of the switching power IC is connected with a positive end of an output side of an optical coupler OC, a negative end of the output side of the optical coupler OC, a ground end of the switching power IC, a positive end of a high-voltage rectification diode D0, and a negative electrode of the high-voltage half-wave rectification filter electrolytic capacitor C1 are connected together; an AC end of the other pole of the alternating current, one end of an anti-power surge current-limiting resistor r0, and one end of an alternating wave sampling resistor R are connected together, and they are also an alternating current common output end; the other end of the alternating wave sampling resistor R is connected with an input port of the single-chip microcomputer MCU, the other end of the anti-power surge current-limiting resistor r0 is connected with a negative end of the high-voltage rectification diode D0, and an output port of the single-chip microcomputer MCU in series with a resistor R1 is connected with a G pole of the thyristor BCR; a negative end of the voltage stabilizing tube DW is connected with a negative end of an input side LED of the optical coupler OC, and a positive end of the input side LED of the optical coupler OC is connected with the other end of the voltage stabilizing output sampling resistor R5. The design scheme B adopts an AC-DC step-down switching power supply IC, and a non-isolated voltage stabilizing output is formed by using an inductor to provide a working power supply for a single-chip microcomputer to drive a thyristor, so as to realize the scheme that the negative pole of the voltage stabilizing output, one pole of the alternating current and the T1 pole of the BCR thyristor are connected together, and the connection structure is as follows: the one pole of the alternating current, the negative pole of the high-voltage half-wave rectification filter electrolytic capacitor C1, the positive pole of the reverse-connection freewheeling diode D5, the negative pole of the voltage stabilizing output filter capacitor C2, the negative pole of the single-chip microcomputer MCU power supply and the T1 pole of the thyristor BCR are connected together; the one end of the high-frequency step-down inductor L, the positive pole of the voltage stabilizing output filter capacitor C2, the positive pole of the voltage stabilizing feedback diode D6 and the positive pole of the single-chip microcomputer MCU power supply are connected together; the switch tube D end of the switching power supply IC, the positive pole of the high-voltage half-wave rectification filter electrolytic capacitor C1 and the negative pole of the high-voltage rectification diode D0 are connected together; the AC end of the other pole of the alternating current and one end of the anti-power surge current limiting resistor r0 are connected together, and the other end of the alternating current wave sampling resistor R is connected to the input port of the single-chip microcomputer MCU; the other end of the anti-power surge current limiting resistor r0 is connected to the positive pole of the high-voltage rectification diode D0, and the output port of the single-chip microcomputer MCU is connected in series with the resistor R1 to the G pole of the thyristor BCR; the negative pole of the voltage stabilizing feedback diode D6, the positive pole of the power supply of the switching power supply IC, the positive pole of the power supply filter capacitor C3 of the switching power supply IC, and one end of the voltage stabilizing output voltage sampling resistor R7 are connected together; the other end of the voltage stabilizing output voltage sampling resistor R7, one end of the voltage stabilizing output voltage sampling voltage dividing resistor R6 and the feedback control Fb end of the switching power supply IC are connected together; the negative pole of the power supply filter capacitor C3 of the switching power supply IC, the other end of the voltage stabilizing output voltage sampling voltage dividing resistor R6, the negative pole of the power supply of the switching power supply IC, the other end of the high-frequency step-down inductor L and the negative pole of the reverse-connection freewheeling diode D5 are connected together. The connection method of the design scheme B can be further adjusted to a BUCK-BOOST output structure, and the scheme that the positive pole of the voltage stabilizing output, one pole of the alternating current and the T1 pole of the BCR thyristor are connected together is also realized, and the adjustment connection method is as follows: the one pole of the alternating current, the negative pole of the high-voltage half-wave rectification filter electrolytic capacitor C1, the one end of the high-frequency step-down inductor L, the positive pole of the voltage stabilizing output filter capacitor C2, the positive pole of the single-chip microcomputer MCU power supply and the T1 pole of the thyristor BCR are connected together; the positive pole of the reverse-connection freewheeling diode D5, the negative pole of the voltage stabilizing output filter capacitor C2 and the negative pole of the single-chip microcomputer MCU power supply are connected together. Design scheme C, for isolated AC regulated power supply or AC regulated power supply module, for single-chip microcomputer drive thyristor provides working power supply, connection mode adopts 5V DC output positive or negative one of one pole and AC AC pole and BCR thyristor T1 pole connection, 5V DC output positive and negative pole respectively with single-chip microcomputer MCU power supply positive and negative pole is connected, the output port of single-chip microcomputer MCU is connected with the G pole of thyristor BCR in series resistance R1;AC the other pole AC end, it is also AC public output end, one end of AC wave sampling resistance R, the other end of AC wave sampling resistance R is connected with the input port of single-chip microcomputer MCU; Design scheme D, the power supply mode of capacitor step-down bridge rectifier, for single-chip microcomputer drive thyristor provides working power supply, adopts opto-isolator isolated drive thyristor mode, connection structure is as follows: one pole of AC is connected with current-limiting resistor r0 and step-down capacitor C0 to the input end of bridge rectifier D4, the other end of the input of bridge rectifier D4 is connected with the other pole of AC and the T1 pole of BCR thyristor, the two input ends of bridge rectifier D4 are connected with a voltage protector Vz in parallel;The positive end of bridge rectifier D4 output is connected with the positive end of filter capacitor C1 and the input end of linear regulator LDO, the negative end of bridge rectifier D4 output is connected with the negative end of filter capacitor C1, the ground end of linear regulator LDO, the negative end of filter capacitor C2 and the negative pole of single-chip microcomputer MCU power supply;The output end of linear regulator LDO is connected with the positive end of filter capacitor C2 and the positive pole of single-chip microcomputer MCU power supply;The one pole of AC is also the AC public output end, which is connected with AC wave sampling resistance R to the input port of single-chip microcomputer MCU.

5. A single phase induction motor drive module for an air conditioner compressor implemented based on the two phase quasi-ratio frequency conversion method of claim 1, characterized in that, Based on the original phase-shift capacitor operation mode, a quasi-low-frequency two-phase operation mode is added to obtain a transition through a low-speed gear during the start of the air conditioner compressor. The air conditioner single-phase asynchronous motor drive module is a circuit board installed near the compressor of the air conditioner outdoor unit. The control circuit in the quasi-variable frequency two-phase method is arranged on the circuit board, including: a power supply part, BCR1, BCR2, BCR3, MCU, and AC wave sampling resistance R. An AC input connection port (1), a 4-wire connection port (2), and a communication control interface SIP4 (3) are also arranged. The specific connection mode is as follows: the AC input connection port (1) is connected with two compressor power supply wires from the air conditioner indoor unit; the connection points in the 4-wire connection port (2) are three T2 output ends of BCR1, BCR2, and BCR3, and one AC one end connected with one pole of the AC input connection port (1), which are sequentially connected with the main winding, the auxiliary winding, the phase-shift capacitor, and the common end of the main and auxiliary windings of the air conditioner compressor motor; the four pins of the communication control interface SIP4 (3) are +5V RX TX -5V, which can be used as logic level control or RS serial communication. The function implementation mode of the air conditioner single-phase asynchronous motor drive module: when the two compressor power supply lines from the air conditioner indoor unit connected to the port (1) are powered on, the thyristor control circuit of the air conditioner single-phase asynchronous motor drive module outputs two-phase quasi-AC power with a frequency of 16.67 Hz at the BCR1 and BCR2 output connection points on the 4-wire connection port (2), which is used to drive the air conditioner compressor single-phase asynchronous motor to start at low speed; after several seconds, the thyristors BCR1 and BCR3 change to full-wave triggering, and BCR2 is not triggered, and the BCR1 and BCR3 output connection points on the 4-wire connection port (2) output the same full-wave AC power, i.e. change to the normal operation mode of the motor composed of the original phase-shifting capacitor; For the circuit design of the relay that continues to be used or / and the field of high-power air conditioners, the full-wave conduction state switching of BCR1 and BCR3 can be replaced by relay contacts J1 and J2, and the normally closed contacts of relay J1 and J2 are switched to the two-phase quasi-low-frequency AC mode composed of BCR1 and BCR2 for low-speed starting transition at ordinary times; after several seconds of starting buffer, the contacts of relay J1 and J2 are switched to the main winding of the motor being directly connected to the AC power input, and the auxiliary winding of the motor being connected to the phase-shifting capacitor C in series to the AC power input, entering the normal operation mode of the motor composed of the original phase-shifting capacitor.

6. The method of claim 5, wherein the method further comprises: The following four application methods are included: Application method A: the original air conditioner main control board is not changed, and the two compressor power supply lines in the original air conditioner outdoor unit connection are connected to the AC power input connection port (1) of the drive module, i.e. the AC power input connection port (1) and the 4-wire connection port (2) are connected according to the specific connection mode, the communication control interface SIP4 (3) is not used, and the fixed-frequency air conditioner compressor starts every time through the low-speed gear running transition; Application method B: a running mode of setting the compressor to work or stop according to the time length is added to the original fixed-frequency air conditioner main control board, and the air conditioner remote controller is added with the matching function of setting the time length; when the fixed-frequency air conditioner compressor stops working, it includes the low-speed gear running of the compressor motor and a kind of idling state of the compressor, i.e. the two-phase quasi-AC power with a frequency of 16.67 Hz is used to drive the air conditioner compressor motor, so that the compressor is frequently started and stopped at short intervals; it not only can produce the effect of approximate variable-frequency air conditioner, but more importantly, it also provides a test mode for detecting fixed-frequency air conditioners, which can set the work / idling time rotation running at the shortest interval of 1 minute; when entering the test mode running, the readings of each temperature detection point of the air conditioner and the working current of the compressor are sent to the user's computer or mobile phone, so that the user can judge the problem of the air conditioner system; the user can also input the measured data into the air conditioner to correct the difference between the local air conditioner installation environment and the standard air conditioner test environment, and create a more accurate judgment basis for self-checking function; The setting or control command is notified to the drive module through the communication control interface SIP4 (3); The application method C, the original frequency air conditioner main control board and the remote controller are not changed, and the timing infrared remote control device is added to the original frequency air conditioner: the timing infrared remote control device has the function of recording the key code of two air conditioner remote controllers, when the timing infrared remote control device records the infrared code of the minimum temperature refrigeration and non-refrigeration, the timing infrared remote control device will send the recorded two kinds of infrared code in a timing cycle; the cycle code timing interval is set at 5 minutes and 10 minutes; the timing infrared remote control device is a charging type or a plug-in type, which is inserted near the air conditioner and rotates the infrared emission tube to aim at the air conditioner indoor unit; The application method D is used to broaden the application flexibility of the air conditioner compressor single-phase asynchronous motor driving module, and the following functions are added to the air conditioner compressor single-phase asynchronous motor driving module: a. AC input connection port (1) instantaneous power-off control command: if there is no power-off within 2 seconds, it will be normally soft-started and run at full speed until power-off; if there is 0.5 second power-off several times within 2 seconds, it will be regarded as a control command, including power-off once to represent running for 5 minutes and stopping for 5 minutes in a cycle, power-off twice to represent running for 10 minutes and stopping for 5 minutes in a cycle, and power-off three times to represent running for 5 minutes and stopping for 10 minutes in a cycle; b. 3-core or 4-core long connection line is connected to the communication control interface SIP4 (3) for logical level combination control; c. 3-core or 4-core long twisted pair line is connected to the communication control interface SIP4 (3) for RS serial communication control, including setting various time parameters to be recorded in the Flash EEPROM of the MCU single-chip microcomputer, and the power-off does not lose; d. The wireless module is connected to the MCU single-chip microcomputer through the SPI serial interface to realize wireless setting of the low-speed start delay and / or high-low speed running timing cycle rule of the air conditioner compressor.

7. The method of claim 6, further comprising upgrading the test mode function to a self-checking function of a fixed-speed air conditioner. The self-checking process is started by pressing the keys or operating the remote controller, and according to the temperature sensors and compressor working current set by the existing fixed frequency air conditioner, the working / idling running at a specific time interval is automatically selected, the temperature difference change and current change of each temperature sensor caused by the change of running state are used to judge the air conditioner running problem or fault, and the self-checking result is displayed on the display screen of the air conditioner indoor unit or sent to the computer or / and mobile phone through the wireless network.

8. A fan single-phase induction motor speed control module implemented based on the two-phase quasi-variational frequency method of claim 1, characterized by, The fan single-phase asynchronous motor speed regulation module is based on the original phase-shift capacitor operation mode and adds a quasi-low-frequency two-phase running mode to obtain an additional low-speed running mode of the fan motor. The electric fan single-phase asynchronous motor speed regulation module is a circuit board installed in the electric fan base, and the control circuit in the two-phase quasi-frequency conversion method is arranged on the circuit board, including: a power supply part, thyristors BCR1, BCR2, BCR3, an MCU single-chip microcomputer and an alternating current wave sampling resistor R; an alternating current input connection port (1) and a 4-wire connection port (2) are further arranged; the alternating current input connection port (1) is connected with a 220V alternating current input power line; the connection points in the 4-wire connection port (2) are three T2 output ends of the thyristors BCR1, BCR2 and BCR3 and an alternating current one end connected with one pole of the alternating current input connection port (1) in parallel, which are sequentially connected with the main winding, the auxiliary winding, the phase-shifting capacitor and the common end of the main winding and the auxiliary winding of the electric fan motor; The function implementation mode of the electric fan single-phase asynchronous motor speed regulation module is as follows: when the alternating current input connected to the port (1) is powered on, the thyristor control circuit of the electric fan single-phase asynchronous motor speed regulation module outputs two-phase quasi-alternating current with a frequency of 16.67Hz at the BCR1 and BCR2 output connection points on the 4-wire connection port (2), which is used for the electric fan motor to run at a low speed; by plugging in the power supply or the button switch, the single-chip microcomputer can recognize the instantaneous power-off control command, the thyristors BCR1 and BCR3 are changed to full-wave triggering, and BCR2 is not triggered, and the BCR1 and BCR3 output connection points on the 4-wire connection port (2) output the same full-wave alternating current, that is, the motor becomes the full-speed running mode formed by the original phase-shifting capacitor; For the circuit design of the relay for continuous use, the full-wave conduction state switching of the BCR1 and BCR3 can be replaced by the relay contacts J1 and J2, and the normally closed contacts of the relay J1 and J2 switch the two-phase quasi-low-frequency alternating current mode formed by the BCR1 and BCR2 to run at a low speed; once the instantaneous power-off control is switched, the relay J1 and J2 contacts are switched to the main winding of the motor directly connected with the alternating current input, and the auxiliary winding of the motor is connected with the phase-shifting capacitor C in series to the alternating current input, and the motor enters the full-speed running mode formed by the original phase-shifting capacitor.

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