A high-voltage AC chopper sampling circuit, control method and device

Abstract

The present invention discloses a high-voltage AC chopping sampling circuit, a control method, and a device. The circuit includes: an input filter module, a current limiting switching module, a pulse width modulation module, and a low-pass filter module; the input filter module is used to rectify and filter the input voltage; the current limiting switching module is used to switch and match different input voltages and perform current limiting on the filtered voltage output by the input filter module; the pulse width modulation module is used to perform inverse shaping on the current limiting voltage output by the current limiting switching module; and the low-pass filter module is used to perform low-pass filtering on the in-phase voltage output by the pulse width modulation module. The present invention switches and adjusts different operating voltages to adapt to different loads through a current limiting switching circuit, and adjusts different load types through a pulse width modulation circuit. While simplifying the circuit, the difficulty of control is reduced, and the stability and anti-interference ability of the output voltage are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of sampling circuits, and in particular to a high-voltage AC chopper sampling circuit, a control method, and a device. Background Art

[0002] With the advancement of electronic technology, a growing number of electronic devices and products are now available for public use. One common electronic device is the LED light. Due to their sealing, shock resistance, and ability to directly emit red, yellow, blue, green, cyan, orange, purple, and white light, LEDs have become a commonly used light-emitting device.

[0003] To meet the user's lighting needs, dimming settings are required before use. Currently, the most commonly used dimming device is a thyristor controller. This controller adjusts the voltage of the LED lamp's integrated circuit, thereby changing the conduction angle of the AC output voltage and the average RMS value of the AC output. This allows loads such as LED lamps to directly use this average RMS voltage to adjust the amount of power they receive, thereby achieving the purpose of dimming.

[0004] However, the commonly used thyristor controllers currently have the following technical problems: First, the voltage modulated by the thyristor controller is only suitable for purely resistive loads and loads whose working voltage matches the mains power. It is difficult to adapt to capacitive loads, inductive loads or loads working at low voltage. If a capacitive, inductive or low-voltage matching circuit is added to the output end of the thyristor controller, the output voltage is likely to change easily once interference occurs in the circuit due to multiple processing of the electrical signal, which reduces the voltage stability and increases the difficulty of regulation. Moreover, adding a configuration circuit will increase the difficulty and cost of the integrated circuit, which is not suitable for widespread use. Summary of the Invention

[0005] The present invention proposes a high-voltage AC chopper sampling circuit, a control method, and a device. The sampling circuit is provided with a current limiting switching circuit and a pulse width modulation circuit. Different operating voltages are switched and adjusted by the current limiting switching circuit to adapt to different loads, and different load types are adjusted by the pulse width modulation circuit. While simplifying the circuit, the stability of the output voltage is improved.

[0006] A first aspect of an embodiment of the present invention provides a high-voltage AC chopping sampling circuit, the high-voltage AC chopping sampling circuit comprising: an input filtering module, a current limiting switching module, a pulse width modulation module and a low-pass filtering module;

[0007] The input filter module, current limiting switching module, pulse width modulation module and low-pass filter module are connected in sequence;

[0008] The input filtering module is used to perform rectification and filtering on the input voltage;

[0009] The current limiting switching module is used to switch and match different input voltages and perform current limiting processing on the filtered voltage output by the input filtering module;

[0010] The pulse width modulation module is used to perform inverse shaping processing on the current limiting voltage output by the current limiting switching module;

[0011] The low-pass filtering module is used to perform low-pass filtering on the in-phase voltage output by the pulse width modulation module.

[0012] In a possible implementation of the first aspect, the current limiting switching module includes: a switching switch, a first switching resistor, a second switching resistor, a voltage stabilizing diode, a switching filter capacitor, and a current limiting resistor;

[0013] Among them, one end of the switching switch is connected to the input end of the current limiting switching module, the other end of the switching switch is respectively connected to one end of the first switching resistor or one end of the second switching resistor, the other end of the first switching resistor or the other end of the second switching resistor is respectively connected to the negative end of the voltage-regulating diode, one end of the switching filter capacitor and one end of the current-limiting resistor, the positive end of the voltage-regulating diode and the other end of the switching filter capacitor are connected to the ground end, the other end of the current-limiting resistor is connected to the output end of the current-limiting switching module, and the connection end of the switching filter capacitor and the current-limiting resistor is provided with a pulse width debugging input port for inputting a pulse width debugging signal.

[0014] In a possible implementation of the first aspect, the pulse width modulation module includes: a photocoupler, a first modulation resistor, a second modulation resistor, a modulation capacitor, and an NMOS transistor;

[0015] The positive emitter terminal of the photoelectric coupler is connected to the input terminal of the pulse width modulation module, the negative emitter terminal and the receiving E terminal of the photoelectric coupler are respectively connected to the ground terminal, the receiving C terminal of the photoelectric coupler is respectively connected to one end of the first modulation resistor, one end of the modulation capacitor and the gate terminal of the NMOS tube, the other end of the modulation capacitor and the source terminal of the NMOS tube are respectively connected to the ground terminal, the drain terminal of the NMOS tube is connected to one end of the second modulation resistor, the other end of the first modulation resistor and the other end of the second modulation resistor are respectively connected to the power supply terminal, the connection end of the NMOS tube and the second modulation resistor is connected to the output terminal of the pulse width modulation module, and the output terminal of the pulse width modulation module is provided with a pulse width sampling port for collecting pulse width time.

[0016] In a possible implementation of the first aspect, the low-pass filter module includes: a constant current source, a first low-pass filter resistor, a second low-pass filter resistor, a third low-pass filter resistor, a first low-pass filter capacitor, and a second low-pass filter capacitor;

[0017] The switch input end of the constant current source is connected to the input end of the low-pass filter module, the voltage input end of the constant current source is connected to the power supply end, the voltage output end of the constant current source is respectively connected to one end of the first low-pass filter resistor and one end of the second low-pass filter resistor, the other end of the second low-pass filter resistor is respectively connected to one end of the third low-pass filter resistor and one end of the first low-pass filter capacitor, the other end of the third low-pass filter resistor is connected to one end of the second low-pass filter capacitor, the other end of the first low-pass filter resistor, the other end of the first low-pass filter capacitor and the other end of the second low-pass filter capacitor are respectively connected to the ground end, and the connection end of the third low-pass filter resistor and the second low-pass filter capacitor is provided with a voltage sampling port for collecting the average voltage.

[0018] In a possible implementation of the first aspect, the input filter module includes: an input filter resistor, a rectifier bridge stack, and an input filter capacitor;

[0019] The first end and the second end of the rectifier bridge stack are respectively connected to the input end of the input filter module for receiving AC chopping, the third end of the rectifier bridge stack is connected to one end of the input filter resistor, the other end of the input filter resistor is connected to one end of the input filter capacitor, the fourth end of the rectifier bridge stack and the other end of the input filter capacitor are respectively connected to the ground end, and the connection end of the input filter resistor and the input filter capacitor is connected to the output end of the input filter module.

[0020] A second aspect of an embodiment of the present invention provides a control method based on the high-voltage AC chopper sampling circuit as described above, the method comprising:

[0021] After inputting a pulse width modulation signal into the high-voltage AC chopping sampling circuit, collecting and adjusting a time error parameter from the high-voltage AC chopping sampling circuit;

[0022] After the high-voltage AC chopping voltage is input to the high-voltage AC chopping sampling circuit, real-time parameters are collected from the high-voltage AC chopping sampling circuit, the real-time parameters including: real-time pulse width time parameters and real-time average voltage parameters;

[0023] The adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter are analyzed and calculated to obtain a pulse width modulation signal.

[0024] In a possible implementation of the second aspect, the computational analysis includes:

[0025] According to the level value of the real-time average voltage parameter, searching for the error time value corresponding to the level value in the adjustment time error parameter;

[0026] Calculate the modulation time difference between the pulse width time value corresponding to the real-time pulse width time parameter and the error time value;

[0027] A pulse width modulation signal is generated based on the modulation time difference adjustment.

[0028] In a possible implementation manner of the second aspect, the adjusting and generating a pulse width modulation signal based on the time difference includes:

[0029] If the time difference is less than the preset difference, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and an effective pulse width time value and an effective average level value corresponding to the generated pulse width modulation signal are recorded;

[0030] If the time difference is greater than a preset difference, determining the real-time change trend of the circuit at the current time node;

[0031] If the change trend is that the change direction is the same, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and the effective pulse width time value and the effective average level value corresponding to the generated pulse width modulation signal are recorded;

[0032] If the change trend is that the change direction is different, the historical pulse width modulation signal generated at the previous time node is used as the pulse width modulation signal.

[0033] In a possible implementation of the second aspect, determining the real-time change trend of the circuit at the current time node includes:

[0034] Obtaining historical time parameters and historical voltage parameters respectively, wherein the historical time parameters are time values ​​corresponding to previous time nodes, and the historical voltage parameters are voltage values ​​corresponding to previous time nodes;

[0035] Calculating a time difference between the real-time pulse width time parameter and the historical time parameter, and calculating a voltage difference between the real-time average voltage parameter and the historical voltage parameter;

[0036] When the comparison time difference and the comparison voltage difference are both greater than zero, or the comparison time difference and the comparison voltage difference are both less than zero, it is determined that the change trends are in the same change direction;

[0037] Otherwise, it is determined that the change trend is different in the change direction.

[0038] A third aspect of the embodiments of the present invention provides a control device based on the high-voltage AC chopper sampling circuit described above, the device comprising:

[0039] a debugging and collecting module, configured to collect and adjust a time error parameter from the high-voltage AC chopping sampling circuit after inputting a pulse width modulation signal into the high-voltage AC chopping sampling circuit;

[0040] an actual acquisition module, configured to acquire real-time parameters from the high-voltage AC chopping sampling circuit after inputting the high-voltage AC chopping voltage into the high-voltage AC chopping sampling circuit, the real-time parameters including: a real-time pulse width time parameter and a real-time average voltage parameter;

[0041] The analysis and control module is used to perform operation analysis on the adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter to obtain a pulse width modulation signal.

[0042] Compared with the prior art, the high-voltage AC chopper sampling circuit, control method, and device provided by the embodiments of the present invention have the following beneficial effects: the sampling circuit of the present invention is provided with a current limiting switching circuit and a pulse width modulation circuit. Different operating voltages are switched and adjusted by the current limiting switching circuit to adapt to different loads, and different load types are adjusted by the pulse width modulation circuit. While simplifying the circuit, the difficulty of control is reduced, and the stability and anti-interference ability of the output voltage are also improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a structural diagram of a high-voltage AC chopping sampling circuit provided by one embodiment of the present invention;

[0044] Figure 2 This is a circuit schematic diagram of a high-voltage AC chopper sampling circuit provided by one embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the application structure of a high-voltage AC chopper sampling circuit provided by one embodiment of the present invention;

[0046] Figure 4 This is a flow chart of a control method based on a high-voltage AC chopper sampling circuit provided by one embodiment of the present invention;

[0047] Figure 5 The diagram is a structural diagram of a control device based on a high-voltage AC chopper sampling circuit provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0048] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0049] The currently commonly used thyristor controllers have the following technical problems: First, the voltage modulated by the thyristor controller is only suitable for purely resistive loads and loads whose working voltage matches the mains power. It is difficult to adapt to capacitive loads, inductive loads or loads working at low voltage. If a capacitive, inductive or low-voltage matching circuit is added to the output end of the thyristor controller, the electrical signal undergoes multiple processing. Once interference occurs in the circuit, the output voltage is prone to change, which reduces the voltage stability and increases the difficulty of regulation. Moreover, adding a configuration circuit will increase the difficulty and cost of the integrated circuit, which is not suitable for widespread use.

[0050] In order to solve the above problems, a high-voltage AC chopper sampling circuit provided by an embodiment of the present application will be introduced and explained in detail through the following specific embodiments.

[0051] Reference Figure 1 , shows a structural schematic diagram of a high-voltage AC chopper sampling circuit provided by an embodiment of the present invention.

[0052] In one embodiment, the high-voltage AC chopping sampling circuit may include:

[0053] Input filter module, current limiting switching module, pulse width modulation module and low-pass filter module;

[0054] The input filter module, current limiting switching module, pulse width modulation module and low-pass filter module are connected in sequence;

[0055] The input filtering module is used to perform rectification and filtering on the input voltage;

[0056] The current limiting switching module is used to switch and match different input voltages and perform current limiting processing on the filtered voltage output by the input filtering module;

[0057] The pulse width modulation module is used to perform inverse shaping processing on the current limiting voltage output by the current limiting switching module;

[0058] The low-pass filtering module is used to perform low-pass filtering on the in-phase voltage output by the pulse width modulation module.

[0059] During use, the input AC voltage can first pass through the input filtering module, which performs rectification and filtering on the input AC voltage and inputs the filtered voltage into the current limiting switching module; then the current limiting switching module can switch and match different input voltages based on actual use needs, and perform current limiting on the filtered voltage, and send the current-limited voltage to the pulse width modulation module; then the pulse width modulation module can perform inverse shaping on the current-limited voltage to adjust it to the corresponding phase, and transmit the voltage after phase adjustment to the low-pass filtering module; finally, the low-pass filtering module performs low-pass filtering on the adjusted voltage and generates a pulse width modulation signal for subsequent regulation and control to control the lighting of different LED lights.

[0060] In this embodiment, different operating voltages are switched and adjusted to adapt to different loads through a current limiting switching circuit, and different load types are adjusted through a pulse width modulation circuit, thereby improving the stability of the output voltage while simplifying the circuit.

[0061] Reference Figure 2 , shows a circuit schematic diagram of a high-voltage AC chopper sampling circuit provided by an embodiment of the present invention.

[0062] In one embodiment, the input filter module includes: an input filter resistor R1, a rectifier bridge BD1 and an input filter capacitor C1;

[0063] The first end and the second end of the rectifier bridge stack BD1 are respectively connected to the input end of the input filter module for receiving AC chopping. The third end of the rectifier bridge stack BD1 is connected to one end of the input filter resistor R1, and the other end of the input filter resistor R1 is connected to one end of the input filter capacitor C1. The fourth end of the rectifier bridge stack BD1 and the other end of the input filter capacitor C1 are respectively connected to the ground end, and the connection end of the input filter resistor R1 and the input filter capacitor C1 is connected to the output end of the input filter module.

[0064] In one embodiment, the current limiting switching module includes: a switching switch S1, a first switching resistor R2, a second switching resistor R3, a voltage stabilizing diode D1, a switching filter capacitor C2 and a current limiting resistor R4;

[0065] In which, one end of the switching switch S1 is connected to the input end of the current limiting switching module, the other end of the switching switch S1 is respectively connected to one end of the first switching resistor R2 or one end of the second switching resistor R3, the other end of the first switching resistor R2 or the other end of the second switching resistor R3 is respectively connected to the negative end of the voltage-regulating diode D1, one end of the switching filter capacitor C2 and one end of the current-limiting resistor R4, the positive end of the voltage-regulating diode D1 and the other end of the switching filter capacitor C2 are connected to the ground end, the other end of the current-limiting resistor R4 is connected to the output end of the current limiting switching module, and the connection end of the switching filter capacitor C2 and the current-limiting resistor R4 is provided with a pulse width debugging input port for inputting a stable pulse width debugging signal.

[0066] Specifically, the pulse width debugging signal may be a PWM reference debugging signal.

[0067] In one embodiment, the pulse width modulation module includes: a photocoupler OP1, a first modulation resistor R5, a second modulation resistor R6, a modulation capacitor C3 and an NMOS transistor Q1;

[0068] The positive emitter terminal of the photoelectric coupler OP1 is connected to the input terminal of the pulse width modulation module, the negative emitter terminal and the receiving E terminal of the photoelectric coupler OP1 are respectively connected to the ground terminal, the receiving C terminal of the photoelectric coupler OP1 is respectively connected to one end of the first modulation resistor R5, one end of the modulation capacitor C3 and the gate terminal of the NMOS transistor Q1, the other end of the modulation capacitor C3 and the source terminal of the NMOS transistor Q1 are respectively connected to the ground terminal, the drain terminal of the NMOS transistor Q1 is connected to one end of the second modulation resistor R6, the other end of the first modulation resistor R5 and the other end of the second modulation resistor R6 are respectively connected to the power supply terminal, and the connection terminal between the NMOS transistor Q1 and the second modulation resistor R6 is connected to the output terminal of the pulse width modulation module. The output terminal of the pulse width modulation module is provided with a pulse width sampling port for collecting pulse width time.

[0069] The pulse width sampling port can be used to collect real-time pulse width modulation time.

[0070] In one embodiment, the low-pass filter module includes: a constant current source I1, a first low-pass filter resistor R7, a second low-pass filter resistor R8, a third low-pass filter resistor R9, a first low-pass filter capacitor C4 and a second low-pass filter capacitor C5;

[0071] The switch input end of the constant current source I1 is connected to the input end of the low-pass filter module, the voltage input end of the constant current source I1 is connected to the power supply end, the voltage output end of the constant current source I1 is respectively connected to one end of the first low-pass filter resistor R7 and one end of the second low-pass filter resistor R8, the other end of the second low-pass filter resistor R8 is respectively connected to one end of the third low-pass filter resistor R9 and one end of the first low-pass filter capacitor C4, the other end of the third low-pass filter resistor R9 is connected to one end of the second low-pass filter capacitor C5, the other end of the first low-pass filter resistor R7, the other end of the first low-pass filter capacitor C4 and the other end of the second low-pass filter capacitor C5 are respectively connected to the ground end, and the connection end of the third low-pass filter resistor R9 and the second low-pass filter capacitor C5 is provided with a voltage sampling port for collecting the average voltage.

[0072] Specifically, the voltage sampling port can be used to collect real-time average voltage.

[0073] In one embodiment, the high-voltage AC chopped voltage can be rectified by the rectifier bridge BD1, and then passed through the resistor-capacitor filter circuit of the input filter resistor R1 and the input filter capacitor C1, and connected to the common end of the voltage switching switch S1. One end of the S1 switch is connected to the 110V first switching resistor R2, and the other end is connected to the 220V second switching resistor R3. The switch is switched when using different working voltages.

[0074] The voltage-stabilizing diode D1 limits the operating voltage and, together with the current-limiting resistor R4, acts as a current limiter, preventing overcurrent damage to the light-emitting diode (LED) of the optocoupler OP1. The output of the optocoupler OP1 is connected to the NMOS transistor Q1, which inverts and shapes the output voltage to produce a pulse-width modulated voltage in phase. This pulse-width modulated voltage is connected to the switch input of the constant current source I1. The voltage output of the constant current source I1 is connected to the first low-pass filter resistor R7 and the low-pass filter circuit consisting of the second low-pass filter resistor R8, the third low-pass filter resistor R9, the first low-pass filter capacitor C4, and the second low-pass filter capacitor C5.

[0075] The constant current source I1 may be composed of a MOS device or a transistor device.

[0076] Reference Figure 3 , shows a schematic diagram of the application structure of a high-voltage AC chopper sampling circuit provided by an embodiment of the present invention.

[0077] In one embodiment, the input end of the high-voltage AC chopping sampling circuit can be connected to the AC chopping voltage, and the AC chopping voltage can be adjusted and sampled to obtain the pulse width time and voltage level. Finally, the pulse width time and voltage level are analyzed and processed to calculate the final control signal, and then dimming or voltage regulation control is performed through the controller.

[0078] In this embodiment, an embodiment of the present invention provides a high-voltage AC chopper sampling circuit, which has the beneficial effect of: the sampling circuit of the present invention is provided with a current limiting switching circuit and a pulse width modulation circuit, and different operating voltages are switched and adjusted to adapt to different loads through the current limiting switching circuit, and different load types are adjusted through the pulse width modulation circuit. While simplifying the circuit, the difficulty of regulation is reduced, and the stability and anti-interference ability of the output voltage are also improved.

[0079] Reference Figure 4 , shows a flow chart of a control method based on a high-voltage AC chopper sampling circuit provided by an embodiment of the present invention.

[0080] As an example, the control method based on the high-voltage AC chopper sampling circuit may include:

[0081] S11 , after inputting a pulse width modulation signal into the high-voltage AC chopping sampling circuit, collecting and adjusting a time error parameter from the high-voltage AC chopping sampling circuit.

[0082] In one embodiment, the high-voltage AC chopping sampling circuit is provided with a pulse width debugging input port, through which a user can input a PWM reference debugging signal into the high-voltage AC chopping sampling circuit. After the PWM reference debugging signal is input, debugging pulse width parameters and debugging voltage parameters can be collected from the pulse width sampling port and voltage sampling port of the high-voltage AC chopping sampling circuit, respectively, and the debugging pulse width parameters and debugging voltage parameters can be used to calculate the adjustment time error parameter.

[0083] For example, when the circuit parameters are determined, the parameters of the input pulse width modulation signal are specifically: frequency f = 100 Hz, grayscale G = 100, duty cycle n = 0 to 100. After the pulse width modulation signal is input through the pulse width debugging input port, the pulse width time value Push[n] corresponding to each input duty cycle n is sampled through the pulse width sampling port. Among them, the pulse width time unit is microseconds us, and 100 pulse width time values ​​are generated to form the reference pulse width time set Push

[100] = {T0, T1, T2, .....T100} to obtain the debugging pulse width parameters. In the above set, T0, T1, T2, .....T100 represent 0 microseconds, 1 microsecond, 2 microseconds...100 microseconds respectively.

[0084] Similarly, the average voltage level value Volt[n] corresponding to each input duty cycle n is sampled through the voltage sampling port. The average voltage level unit is millivolts (mV). 100 average voltage values ​​are generated to form the reference average voltage set Volt

[100] = {V0, V1, V2, .....V100}, thereby obtaining the debugging voltage parameter. In the above set, V0, V1, V2, .....V100 represent 0 mV, 1 mV, 2 mV, .....100 mV, respectively.

[0085] It should be noted that the 100 times of the debugging pulse width parameter and the 100 voltage values ​​of the debugging voltage parameter are in one-to-one correspondence, and each time corresponds to a voltage value.

[0086] Based on the value of the debug pulse width parameter, a set of pulse width time error sets Du

[100] = {D0, D1, D2, .....D100} with an allowable fluctuation range that corresponds one-to-one with each pulse width time set Push[n] is determined. The unit of the pulse width time error is microseconds (us). This set of pulse width time error values ​​is the adjusted time error parameter. In the above set, since each voltage value corresponds to a time of the debug pulse width parameter, and each time corresponds to a time error value, each voltage value corresponds to a time error value.

[0087] Optionally, the adjustment time error parameter can be estimated based on the value of the debugging pulse width parameter (eg, Push

[100] ).

[0088] Specifically, the estimation method for adjusting the time error parameter can be performed during the debugging signal circuit. The method is to calculate the difference between the duty cycle time of each input PWM signal and the pulse width time of the detected output PWM after inputting the debugging signal. This difference is allowed to fluctuate within a small range. This series of differences forms the pulse width time error set Du

[100] .

[0089] S12. After inputting the high-voltage AC chopping voltage to the high-voltage AC chopping sampling circuit, real-time parameters are collected from the high-voltage AC chopping sampling circuit. The real-time parameters include: real-time pulse width time parameters and real-time average voltage parameters.

[0090] After obtaining and recording the debugging data, the AC chopping voltage can be started and connected, and then the actual AC chopping voltage can be input into the circuit to collect the circuit parameters output by the circuit after the actual AC chopping voltage is input.

[0091] Specifically, after inputting the AC chopping voltage, the corresponding pulse width time and voltage value can also be collected through the pulse width sampling port and the voltage sampling port respectively, so as to obtain the real-time pulse width time parameter and the real-time average voltage parameter respectively.

[0092] It should be noted that the sampling method of the real-time pulse width time parameter and the real-time average voltage parameter is the same as the sampling method of the debugging pulse width parameter and the debugging voltage parameter in step S11. In order to avoid repetition, they will not be described here. For details, please refer to the above description.

[0093] S13, performing calculation and analysis on the adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter to obtain a pulse width modulation signal.

[0094] After obtaining the adjustment time error parameter, real-time pulse width time parameter and real-time average voltage parameter, the above three parameters can be used to perform corresponding logical calculations to adjust and generate the corresponding pulse width modulation signal, so that the LED lamp can be dimmed and the voltage adjusted according to the pulse width modulation signal.

[0095] In order to adapt to actual conditions and improve the accuracy of calculation and analysis, in one embodiment, step S13 may include the following sub-steps:

[0096] Sub-step S131 : searching for an error time value corresponding to the level value in the adjustment time error parameter according to the level value of the real-time average voltage parameter.

[0097] Referring to the above example, since the voltage value and the time error value are in a one-to-one correspondence, the numerical value of the real-time average voltage parameter is first determined, and then the error time value of the corresponding level value in the time error parameter is adjusted according to the numerical value of the real-time average voltage parameter.

[0098] Sub-step S132: Calculate the modulation time difference between the pulse width time value corresponding to the real-time pulse width time parameter and the error time value.

[0099] The difference between the pulse width time value corresponding to the real-time pulse width time parameter and the error time value can be directly calculated to obtain the modulation time difference.

[0100] Sub-step S133: adjusting and generating a pulse width modulation signal based on the modulation time difference.

[0101] Optionally, a corresponding pulse width modulation signal may be generated based on the numerical value of the modulation time difference.

[0102] In one embodiment, sub-step S133 may include the following sub-steps:

[0103] Sub-step S1331: If the time difference is less than the preset difference, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and the effective pulse width time value and the effective average level value corresponding to the generated pulse width modulation signal are recorded.

[0104] If the time difference is less than the preset difference, it means that the sampled value is valid. The value of the level of the real-time average voltage parameter can be used as the duty cycle output pulse width modulation signal Pt at time t. At the same time, the effective pulse width time value Tt and the effective average level value Vt at time t can also be recorded, where t can be the pulse width time.

[0105] Sub-step S1332: If the time difference is greater than the preset difference, determine the real-time change trend of the circuit at the current time node.

[0106] If the time difference is greater than the preset difference, it means that the sampled value exceeds the predetermined error time range, and it is necessary to determine whether the sampled value is valid.

[0107] Specifically, the real-time change trend of the circuit parameters at the current time node can be determined, and then whether the sampling parameters are valid can be determined based on the change trend, and then whether the sampling parameters should be used for subsequent calculations can be determined.

[0108] In order to accurately determine the specific change trend, in one embodiment, step S1332 may include the following sub-steps:

[0109] Sub-step S13321: Obtain historical time parameters and historical voltage parameters respectively, wherein the historical time parameters are time values ​​corresponding to previous time nodes, and the historical voltage parameters are voltage values ​​corresponding to previous time nodes.

[0110] Specifically, the previous time node may be the time node at which sampling was performed at the previous moment. Correspondingly, the historical time parameter is the time value collected at the previous moment, specifically the pulse width time; and the historical voltage parameter is the voltage value collected at the previous moment.

[0111] Sub-step S13322: Calculate the time difference between the real-time pulse width time parameter and the historical time parameter, and calculate the voltage difference between the real-time average voltage parameter and the historical voltage parameter.

[0112] Specifically, the difference between the real-time pulse width time parameter and the historical time parameter can be calculated to obtain the comparative time difference; similarly, the difference between the real-time average voltage parameter and the historical voltage parameter can be calculated to obtain the comparative voltage difference.

[0113] Sub-step S13323: When the comparison time difference and the comparison voltage difference are both greater than zero, or the comparison time difference and the comparison voltage difference are both less than zero, it is determined that the change trends are in the same direction.

[0114] Sub-step S13324: Otherwise, determine that the change trend is that the change direction is different.

[0115] Specifically, when the comparison time difference is greater than zero, it indicates that the time is in an increasing direction, otherwise, it indicates that the time is in a decreasing direction; similarly, when the comparison voltage difference is greater than zero, it indicates that the voltage is in an increasing direction, otherwise, it indicates that the voltage is in a decreasing direction.

[0116] When the pulse width time and the average level increase or decrease at the same time, that is, the change direction is the same, then it can be judged that the value sampled at time t is valid; when the pulse width time is in an increasing change direction and the average level is in a decreasing change direction, or when the pulse width time is in a decreasing change direction and the average level is in an increasing change direction, then the change directions are different and the collected data is invalid.

[0117] Sub-step S1333: If the change trend is the same change direction, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and the effective pulse width time value and the effective average level value corresponding to the generated pulse width modulation signal are recorded.

[0118] Sub-step S1334: If the change trend is that the change direction is different, then the historical pulse width modulation signal generated at the previous time node is used as the pulse width modulation signal.

[0119] When the changing trend is that the changing direction is the same, the pulse width modulation signal can be directly generated using the level value of the real-time average voltage parameter as the duty cycle time; when the changing trend is that the changing direction is different, the pulse width modulation signal sampled at the previous time t-1 is used as the pulse width modulation signal at the current time t.

[0120] In one embodiment, the method may further include:

[0121] S14: Transmitting the pulse width modulation signal to a preset control unit so that the preset control unit can control the light source.

[0122] After the pulse width modulation signal is obtained, the pulse width modulation signal can be transmitted to a corresponding control unit for the corresponding control unit to perform corresponding regulation processing.

[0123] Reference Figure 3 In one embodiment, the preset control unit may be an MCU control unit.

[0124] In this embodiment, an embodiment of the present invention provides a control method based on a high-voltage AC chopper sampling circuit. Its beneficial effect is that the present invention can collect two corresponding parameters, pulse width time and average voltage, when the high-voltage AC chopper sampling circuit is in two states: debugging and actual use. Based on the circuit parameters collected in the two different states, analysis and calculation are performed to screen and determine the corresponding duty cycle time. Therefore, an effective modulation signal can be generated based on the duty cycle time conversion to accurately control the circuit back-end devices to perform corresponding operations. The present invention not only reduces the difficulty of control, but also improves the accuracy and control effect of control.

[0125] The embodiment of the present invention also provides a control device based on a high voltage AC chopper sampling circuit, see Figure 5 , shows a structural schematic diagram of a control device based on a high-voltage AC chopper sampling circuit provided by an embodiment of the present invention.

[0126] As an example, the control device based on the high-voltage AC chopper sampling circuit may include:

[0127] The debugging and collecting module 501 is used to collect and adjust the time error parameter from the high-voltage AC chopping sampling circuit after inputting the pulse width modulation signal into the high-voltage AC chopping sampling circuit;

[0128] The actual acquisition module 502 is configured to acquire real-time parameters from the high-voltage AC chopping sampling circuit after inputting the high-voltage AC chopping voltage into the high-voltage AC chopping sampling circuit. The real-time parameters include: a real-time pulse width time parameter and a real-time average voltage parameter;

[0129] The analysis and control module 503 is used to perform calculation and analysis on the adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter to obtain a pulse width modulation signal.

[0130] Optionally, the analysis and control module is further used to:

[0131] According to the level value of the real-time average voltage parameter, searching for the error time value corresponding to the level value in the adjustment time error parameter;

[0132] Calculate the modulation time difference between the pulse width time value corresponding to the real-time pulse width time parameter and the error time value;

[0133] A pulse width modulation signal is generated based on the modulation time difference adjustment.

[0134] Optionally, the analysis and control module is further used to:

[0135] If the time difference is less than the preset difference, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and an effective pulse width time value and an effective average level value corresponding to the generated pulse width modulation signal are recorded;

[0136] If the time difference is greater than a preset difference, determining the real-time change trend of the circuit at the current time node;

[0137] If the change trend is that the change direction is the same, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and the effective pulse width time value and the effective average level value corresponding to the generated pulse width modulation signal are recorded;

[0138] If the change trend is that the change direction is different, the historical pulse width modulation signal generated at the previous time node is used as the pulse width modulation signal.

[0139] Optionally, the analysis and control module is further used to:

[0140] Obtaining historical time parameters and historical voltage parameters respectively, wherein the historical time parameters are time values ​​corresponding to previous time nodes, and the historical voltage parameters are voltage values ​​corresponding to previous time nodes;

[0141] Calculating a time difference between the real-time pulse width time parameter and the historical time parameter, and calculating a voltage difference between the real-time average voltage parameter and the historical voltage parameter;

[0142] When the comparison time difference and the comparison voltage difference are both greater than zero, or the comparison time difference and the comparison voltage difference are both less than zero, it is determined that the change trends are in the same change direction;

[0143] Otherwise, it is determined that the change trend is different in the change direction.

[0144] Those skilled in the art can clearly understand that, for the sake of convenience and brevity, the specific working process of the device described above can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0145] Furthermore, an embodiment of the present application also provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the control method based on the high-voltage AC chopper sampling circuit as described in the above embodiment is implemented.

[0146] Furthermore, an embodiment of the present application also provides a computer-readable storage medium, which stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the control method based on the high-voltage AC chopper sampling circuit as described in the above embodiment.

[0147] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A high voltage AC chopper sampling circuit, characterized in that: The high-voltage AC chopping sampling circuit includes: an input filter module, a current limiting switching module, a pulse width modulation module and a low-pass filter module; The input filter module, current limiting switching module, pulse width modulation module and low-pass filter module are connected in sequence; The input filtering module is used to perform rectification and filtering on the input voltage; The current limiting switching module is used to switch and match different input voltages and perform current limiting processing on the filtered voltage output by the input filtering module; The pulse width modulation module is used to perform inverse shaping processing on the current limiting voltage output by the current limiting switching module; The low-pass filtering module is used to perform low-pass filtering on the in-phase voltage output by the pulse width modulation module; The current limiting switching module includes: a switching switch, a first switching resistor, a second switching resistor, a voltage stabilizing diode, a switching filter capacitor and a current limiting resistor; Among them, one end of the switching switch is connected to the input end of the current limiting switching module, the other end of the switching switch is respectively connected to one end of the first switching resistor or one end of the second switching resistor, the other end of the first switching resistor or the other end of the second switching resistor is respectively connected to the negative end of the voltage-regulating diode, one end of the switching filter capacitor and one end of the current-limiting resistor, the positive end of the voltage-regulating diode and the other end of the switching filter capacitor are connected to the ground end, the other end of the current-limiting resistor is connected to the output end of the current-limiting switching module, and the connection end of the switching filter capacitor and the current-limiting resistor is provided with a pulse width debugging input port for inputting a pulse width debugging signal.

2. The high-voltage AC chopper sampling circuit according to claim 1, characterized in that: The pulse width modulation module includes: a photoelectric coupler, a first modulation resistor, a second modulation resistor, a modulation capacitor and an NMOS tube; The positive emitter terminal of the photoelectric coupler is connected to the input terminal of the pulse width modulation module, the negative emitter terminal and the receiving E terminal of the photoelectric coupler are respectively connected to the ground terminal, the receiving C terminal of the photoelectric coupler is respectively connected to one end of the first modulation resistor, one end of the modulation capacitor and the gate terminal of the NMOS tube, the other end of the modulation capacitor and the source terminal of the NMOS tube are respectively connected to the ground terminal, the drain terminal of the NMOS tube is connected to one end of the second modulation resistor, the other end of the first modulation resistor and the other end of the second modulation resistor are respectively connected to the power supply terminal, the connection end of the NMOS tube and the second modulation resistor is connected to the output terminal of the pulse width modulation module, and the output terminal of the pulse width modulation module is provided with a pulse width sampling port for collecting pulse width time.

3. The high-voltage AC chopping sampling circuit according to claim 1, characterized in that: The low-pass filter module includes: a constant current source, a first low-pass filter resistor, a second low-pass filter resistor, a third low-pass filter resistor, a first low-pass filter capacitor and a second low-pass filter capacitor; The switch input end of the constant current source is connected to the input end of the low-pass filter module, the voltage input end of the constant current source is connected to the power supply end, the voltage output end of the constant current source is respectively connected to one end of the first low-pass filter resistor and one end of the second low-pass filter resistor, the other end of the second low-pass filter resistor is respectively connected to one end of the third low-pass filter resistor and one end of the first low-pass filter capacitor, the other end of the third low-pass filter resistor is connected to one end of the second low-pass filter capacitor, the other end of the first low-pass filter resistor, the other end of the first low-pass filter capacitor and the other end of the second low-pass filter capacitor are respectively connected to the ground end, and the connection end of the third low-pass filter resistor and the second low-pass filter capacitor is provided with a voltage sampling port for collecting the average voltage.

4. The high-voltage AC chopping sampling circuit according to claim 1, characterized in that: The input filter module includes: an input filter resistor, a rectifier bridge stack and an input filter capacitor; The first end and the second end of the rectifier bridge stack are respectively connected to the input end of the input filter module for receiving AC chopping, the third end of the rectifier bridge stack is connected to one end of the input filter resistor, the other end of the input filter resistor is connected to one end of the input filter capacitor, the fourth end of the rectifier bridge stack and the other end of the input filter capacitor are respectively connected to the ground end, and the connection end of the input filter resistor and the input filter capacitor is connected to the output end of the input filter module.

5. A control method based on the high-voltage AC chopper sampling circuit according to any one of claims 1 to 4, characterized in that: The method comprises: After inputting a pulse width modulation signal into the high-voltage AC chopping sampling circuit, collecting and adjusting a time error parameter from the high-voltage AC chopping sampling circuit; After the high-voltage AC chopping voltage is input to the high-voltage AC chopping sampling circuit, real-time parameters are collected from the high-voltage AC chopping sampling circuit, the real-time parameters including: real-time pulse width time parameters and real-time average voltage parameters; The adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter are analyzed and calculated to obtain a pulse width modulation signal.

6. The control method according to claim 5, characterized in that: The operational analysis includes: According to the level value of the real-time average voltage parameter, searching for the error time value corresponding to the level value in the adjustment time error parameter; Calculate the modulation time difference between the pulse width time value corresponding to the real-time pulse width time parameter and the error time value; A pulse width modulation signal is generated based on the modulation time difference adjustment.

7. The control method according to claim 6, characterized in that: The step of adjusting and generating a pulse width modulation signal based on the time difference comprises: If the time difference is less than the preset difference, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and an effective pulse width time value and an effective average level value corresponding to the generated pulse width modulation signal are recorded; If the time difference is greater than a preset difference, determining the real-time change trend of the circuit at the current time node; If the change trend is that the change direction is the same, a pulse width modulation signal is generated with the level value of the real-time average voltage parameter as the duty cycle time, and the effective pulse width time value and the effective average level value corresponding to the generated pulse width modulation signal are recorded; If the change trend is that the change direction is different, the historical pulse width modulation signal generated at the previous time node is used as the pulse width modulation signal.

8. The control method according to claim 7, characterized in that: Determining the real-time change trend of the circuit at the current time node includes: Obtaining historical time parameters and historical voltage parameters respectively, wherein the historical time parameters are time values ​​corresponding to previous time nodes, and the historical voltage parameters are voltage values ​​corresponding to previous time nodes; Calculating a time difference between the real-time pulse width time parameter and the historical time parameter, and calculating a voltage difference between the real-time average voltage parameter and the historical voltage parameter; When the comparison time difference and the comparison voltage difference are both greater than zero, or the comparison time difference and the comparison voltage difference are both less than zero, it is determined that the change trends are in the same change direction; Otherwise, it is determined that the change trend is different in the change direction.

9. A control device based on the high-voltage AC chopper sampling circuit according to any one of claims 1 to 4, characterized in that: The device comprises: a debugging and collecting module, configured to collect and adjust a time error parameter from the high-voltage AC chopping sampling circuit after inputting a pulse width modulation signal into the high-voltage AC chopping sampling circuit; an actual acquisition module, configured to acquire real-time parameters from the high-voltage AC chopping sampling circuit after inputting the high-voltage AC chopping voltage into the high-voltage AC chopping sampling circuit, the real-time parameters including: a real-time pulse width time parameter and a real-time average voltage parameter; The analysis and control module is used to perform operation analysis on the adjustment time error parameter, the real-time pulse width time parameter and the real-time average voltage parameter to obtain a pulse width modulation signal.

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