Wave sending method and system of DC-DC converter

Abstract

The invention discloses a wave sending method and system for a DC-DC converter, and belongs to the technical field of power electronics, and the method comprises the steps: initializing a chip, and setting the related parameters of a carrier signal; based on the carrier signal and a preset condition, respectively setting a plurality of PWM wave signal waveforms output by the chip; based on the plurality of PWM wave signals after setting, establishing different wave sending modes; a duty ratio value is input and updated, and a plurality of updated PWM wave signals are output according to the updated duty ratio value; and selecting a corresponding wave sending mode according to the plurality of updated PWM wave signals so as to control the output voltage of the DC-DC converter. According to the invention, through flexible setting and mode switching of a plurality of PWM wave signals, the amplitude and frequency of the output voltage can be dynamically adjusted according to the input duty ratio value, thereby realizing fine regulation and control of the performance of the DC-DC converter.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to a wave generation method and system for a DC-DC converter. Background Art

[0002] As a key power conversion device, DC-DC converter is widely used in various DC power supply systems. Its main function is to convert a fixed DC voltage into another variable DC voltage to meet the specific voltage requirements of different electronic devices. The working principle of DC-DC converter is based on the periodic conduction and disconnection of electronic switching devices. By adjusting the working state of the switching devices, the output voltage can be accurately controlled and adjusted.

[0003] The existing DC-DC control circuit is the PWM control of the MCU. A total of 18 groups of registers are required to realize six-channel PWM output, which are the period register, duty cycle register, and count register of each PWM. In order to realize the alignment relationship between the PWM signals of the control circuit, it is necessary to configure 6 channels of the timer output module. At the same time, in order to realize the reference relationship, the channel resources of the timer output module of the inverter tube Q1 / Q3PWM signal, the inverter tube Q2 / Q4PWM signal, the rectifier tube S1PWM signal, the rectifier tube S2PWM signal, the absorption tube VT1PWM signal, and the absorption tube VT2PWM signal all need the reference carrier period channel. This control circuit occupies a large amount of resources and is difficult to meet the needs of fine control of multiple PWM signals. At the same time, the frequency and amplitude adjustment of the PWM signal are greatly restricted, making it difficult to realize flexible regulation of the performance of the DC-DC converter. Summary of the invention

[0004] To solve the above problems, the present invention provides a wave generation method and system for a DC-DC converter. Through flexible setting and mode switching of multiple PWM wave signals, the amplitude and frequency of the output voltage can be dynamically adjusted according to the input duty cycle value, thereby achieving fine control of the performance of the DC-DC converter.

[0005] The above objectives can be achieved through the following solutions:

[0006] A wave generation method for a DC-DC converter comprises: initializing a chip and setting carrier signal related parameters; setting the waveforms of a plurality of PWM wave signals output by the chip respectively based on the carrier signal and preset conditions; establishing different wave generation modes based on the set plurality of PWM wave signals; inputting and updating a duty cycle value, and outputting the updated plurality of PWM wave signals according to the updated duty cycle value; and selecting the corresponding wave generation mode according to the updated plurality of PWM wave signals to realize control of the output voltage of the DC-DC converter.

[0007] Optionally, the multiple PWM wave signals include: Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT2 absorption tube PWM wave signal; wherein, the high level centers of the Q1 / Q3 inverter tube PWM wave signal, the S2 rectifier tube PWM wave signal and the VT2 absorption tube PWM wave signal all fall at the center position of the carrier signal; the high level centers of the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal and the VT1 absorption tube PWM wave signal all fall at the sending position of the carrier signal.

[0008] Optionally, the preset conditions include: the phase difference between the high-level signal of the Q1 / Q3 inverter tube PWM wave and the high-level signal of the Q2 / Q4 inverter tube PWM wave is 180 degrees; the Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal both refer to the carrier signal period, and the Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal are complementary and have a dead zone; the Q1 / Q3 inverter tube PWM wave signal and the VT1 absorption tube PWM wave signal both refer to the carrier period, and the Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal are complementary and have a dead zone. The PWM wave signal of the Q2 / Q4 inverter tube is complementary to the PWM wave signal of the VT1 absorption tube, and there is no dead zone; the PWM wave signal of the Q2 / Q4 inverter tube and the PWM wave signal of the S2 rectifier tube both refer to the carrier cycle, and the PWM wave signal of the Q2 / Q4 inverter tube is complementary to the PWM wave signal of the S2 rectifier tube, and there is a dead zone; the PWM wave signal of the Q2 / Q4 inverter tube and the PWM wave signal of the VT2 absorption tube both refer to the carrier cycle, and the PWM wave signal of the Q2 / Q4 inverter tube is complementary to the PWM wave signal of the VT2 absorption tube, and there is no dead zone.

[0009] Optionally, the method further includes: initializing a CPU module of the chip; and setting channels and switching states of the carrier signal and the multiple PWM wave signals.

[0010] Optionally, the wave-generating mode includes: a full-off mode, a full-wave-generating mode, a mode in which the inverter tube absorber tube generates waves and the rectifier tube does not generate waves, a mode in which the rectifier tube generates waves and the inverter tube absorber tube does not generate waves, and a mode in which the rectifier tube absorber tube generates waves and the inverter tube does not generate waves; wherein the full-off mode is the mode in which the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorber tube PWM wave signal and the VT2 absorber tube P are generated. The waveforms of the WM wave signals are all low level; the full wave transmission mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally transmitted and meet the preset conditions; the inverter tube absorption tube wave transmission and rectifier tube non-wave transmission mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube The PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions, and the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both low level; the rectifier tube wave-generating inverter tube absorption tube non-wave-generating mode is that the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are all normally emitted and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all low level; the rectifier tube absorption tube wave-generating inverter tube non-wave-generating mode is that the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal are all low level.

[0011] Optionally, the inputting and updating the duty cycle value includes: inputting a new duty cycle value; and updating the duty cycle values ​​of the multiple PWM wave signals to the new duty cycle value in the next cycle.

[0012] Optionally, outputting the updated multiple PWM wave signals according to the updated duty cycle values ​​includes: the updated multiple PWM wave signals are output in the next cycle after the duty cycle values ​​of the multiple PWM wave signals are updated; and the updated multiple PWM wave signals can meet the preset conditions.

[0013] Optionally, the method also includes: the S1 rectifier, the S2 rectifier, the Q1 / Q3 inverter, and the Q2 / Q4 inverter are controlled by registers of the same group but different channels; the periods of the Q1 / Q3 inverter PWM wave signal, the Q2 / Q4 inverter PWM wave signal, the S1 rectifier PWM wave signal, the S2 rectifier PWM wave signal, the VT1 absorption tube PWM wave signal, and the VT2 absorption tube PWM wave signal all refer to the period of the carrier signal.

[0014] Based on the same inventive concept, the present invention also provides a wave generation system for a DC-DC converter, the system comprising: an initialization module, used to initialize the chip and set the carrier signal; a PWM wave signal setting module, used to set multiple PWM wave signals respectively based on the carrier signal and preset conditions; the PWM wave signal setting module is also used to establish different wave generation modes based on the multiple PWM wave signals after setting; a PWM wave signal generation module, used to input and update the duty cycle value, and output the updated multiple PWM wave signals according to the updated duty cycle value; a control module, used to select the corresponding wave generation mode according to the updated multiple PWM wave signals, so as to realize the control of the output voltage of the DC-DC converter.

[0015] Optionally, the PWM wave signal generating module includes: a TOM submodule, which is used to monitor time and trigger an update operation at the end of each carrier signal cycle; a duty cycle shadow register, which is used to receive and store the duty cycle value to be applied in the next carrier signal cycle; a duty cycle register, which is used to store the duty cycle value actually used in the current carrier signal cycle; the duty cycle register is also used to receive the duty cycle value sent by the duty cycle shadow register before the start of each carrier signal cycle; a period shadow register, which is used to receive and store the period value to be applied in the next carrier signal cycle; a period register, which is used to store the period value actually used in the current carrier signal cycle; the period register is also used to receive the period value sent by the period shadow register before the start of each carrier signal cycle; a GTM submodule, which is used to generate the carrier signal; the GTM module is also used to read the duty cycle value in the duty cycle register and the period value in the period register at the beginning of each carrier signal cycle, and generate a PWM wave signal according to the read duty cycle value and period value.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. The present invention realizes refined control of PWM wave at the software level, and can conveniently realize precise control of the output voltage of the DC-DC converter by adjusting the duty cycle and period of the PWM wave. This control method provides high flexibility and programmability;

[0018] 2. The present invention utilizes the GTM submodule of the Infineon microprocessor AURIX series products to realize the output of multiple PWM waves by means of the counter counting up and overflowing to zero, while reducing the use of register resources. Each PWM wave is controlled by a separate channel of the TOM submodule, thereby optimizing resource allocation; by calculating and updating the duty ratio and period registers of different channels of the TOM submodule, no additional timer is required for alignment, thereby simplifying the PWM structure and reducing the complexity and cost of the circuit;

[0019] 3. The present invention effectively avoids the problem of direct connection of the upper and lower bridge arms at each stage by adjusting the switching states of multiple PWM wave channels, thereby improving the stability and safety of the circuit;

[0020] 4. The present invention provides five different wave-generating modes, including a full-off mode, a full-wave-generating mode, a mode in which the inverter tube and the absorber tube generate waves and the rectifier tube does not generate waves, a mode in which the rectifier tube generates waves and the inverter tube and the absorber tube does not generate waves, and a mode in which the rectifier tube and the absorber tube generate waves and the inverter tube does not generate waves. These modes can be selected and switched according to actual needs to meet the needs of different application scenarios;

[0021] 5. The present invention improves the quality of the output waveform, reduces problems such as overshoot voltage and electromagnetic interference, and improves the performance and reliability of the circuit through precise timing control and dead time design.

[0022] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 The present invention is a flowchart of a method for generating a wave of a DC-DC converter according to an embodiment of the present invention.

[0025] Figure 2 The present invention is a flowchart of a DC-DC converter wave generation method according to an embodiment of the present invention.

[0026] Figure 3It is a waveform diagram of the PWM wave signal of the Q1 / Q3 inverter tube and the PWM wave signal of the Q2 / Q4 inverter tube according to the embodiment of the present invention.

[0027] Figure 4 It is a waveform diagram of the PWM wave signal of the Q1 / Q3 inverter tube, the PWM wave signal of the S1 rectifier tube, and the PWM wave signal of the VT1 absorption tube in the embodiment of the present invention.

[0028] Figure 5 It is a waveform diagram of the PWM wave signal of the Q2 / Q4 inverter tube, the PWM wave signal of the S2 rectifier tube, and the PWM wave signal of the VT2 absorption tube in the embodiment of the present invention.

[0029] Figure 6 It is a timing diagram of the wave generation in the full-off mode of an embodiment of the present invention.

[0030] Figure 7 It is a timing diagram of the full-wave transmission mode of an embodiment of the present invention.

[0031] Figure 8 It is a wave generation timing diagram of the inverter tube, the absorption tube, the wave generation, and the rectifier tube in the non-wave generation mode of the embodiment of the present invention.

[0032] Fig. 9 It is a wave generation timing diagram of a mode in which a rectifier tube generates waves and an inverter tube does not generate waves according to an embodiment of the present invention.

[0033] Fig.10 It is a wave generation timing diagram of the rectifier tube, the absorption tube, the wave generation, and the inverter tube non-wave generation mode in an embodiment of the present invention.

[0034] Fig.11 It is a structural schematic diagram of a wave generating system of a DC-DC converter according to an embodiment of the present invention.

[0035] Fig.12 It is a structural diagram of a PWM wave signal generating module according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Reference Figure 1An embodiment of the present invention proposes a wave generation method for a DC-DC converter. Through flexible setting and mode switching of multiple PWM wave signals, the amplitude and frequency of the output voltage can be dynamically adjusted according to the input duty cycle value, thereby achieving fine control of the performance of the DC-DC converter.

[0038] The method of this embodiment specifically includes:

[0039] Initialize the chip and set the carrier signal related parameters;

[0040] Based on the carrier signal and preset conditions, the waveforms of multiple PWM wave signals output by the chip are respectively set;

[0041] Based on the set multiple PWM wave signals, different wave generation modes are established;

[0042] Inputting and updating the duty cycle value, and outputting the updated multiple PWM wave signals according to the updated duty cycle value;

[0043] The corresponding wave generation mode is selected according to the updated multiple PWM wave signals to achieve control of the output voltage of the DC-DC converter.

[0044] For example, Figure 2 As shown, the chip may be a CPU of an Infineon AURIX series microprocessor, the CPU of the Infineon AURIX series microprocessor is initialized, and a carrier signal with a fixed frequency and duty cycle is set to be generated as a reference signal; with the carrier signal as the reference signal, multiple PWM wave signals are set according to preset conditions, and the periods of the multiple PWM wave signals will be the same as the period of the carrier signal, wherein the preset conditions may be a specific relationship between the multiple PWM wave signals; according to the set Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT 2. The PWM wave signal of the absorbing tube is used to establish five wave generation modes. Different wave generation modes correspond to different control effects of the DC-DC converter on the output voltage. When the output voltage of the DC-DC converter needs to be adjusted, the duty cycle value is input to update the duty cycle of multiple PWM waves to output multiple new PWM wave signals. According to the edge signal of the carrier signal cycle, the level rising edge and falling edge of each PWM wave signal are generated by calculation. The corresponding wave generation mode is selected according to the level rising edge and falling edge of each PWM wave signal. By selecting the duty cycle and phase relationship of the PWM wave signal under different wave generation modes, the output voltage of the DC-DC converter can be accurately controlled.

[0045] Optionally, the multiple PWM wave signals include: Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT2 absorption tube PWM wave signal; wherein,

[0046] The high level centers of the Q1 / Q3 inverter tube PWM wave signal, the S2 rectifier tube PWM wave signal and the VT2 absorption tube PWM wave signal all fall at the center position of the carrier signal;

[0047] Exemplarily, the carrier signal is set to a periodic square wave signal with a frequency of 80KHz and a duty cycle of 50%, which means that the high level and low level of the carrier signal each occupy half a cycle; the high level center of the PWM wave signal of the Q1 / Q3 inverter tube is set to align with the center position of the carrier signal; assuming that the period of the carrier signal is 12.5 microseconds (1 / 80KHz), the high level center is located at 6.25 microseconds, therefore, the high level center of the PWM wave signal of the Q1 / Q3 inverter tube is also set at 6.25 microseconds, but its duty cycle will be adjusted as needed; the high level center of the PWM wave signal of the S2 rectifier tube and the VT2 absorption tube is also set to align with the center position of the carrier signal, which means that their high level centers are also located at 6.25 microseconds, but their duty cycle and phase relationship will be adjusted according to the complementary relationship with the PWM wave signal of the Q1 / Q3 inverter tube.

[0048] The high level centers of the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal and the VT1 absorption tube PWM wave signal all fall on the sending position of the carrier signal.

[0049] Exemplarily, the carrier signal is set to a periodic square wave signal with a frequency of 80KHz and a duty cycle of 50%, which means that the high level and low level of the carrier signal each occupy half a period; the high level center of the PWM wave signal of the Q2 / Q4 inverter tube is set to align with the emission position of the carrier signal. Assuming that the period of the carrier signal is 12.5 microseconds (1 / 80KHz), the high level center is located at 6.25 microseconds, therefore, the high level center of the PWM wave signal of the Q2 / Q4 inverter tube is set at 0 microseconds; the high level centers of the S1 rectifier tube PWM wave signal and the VT1 absorption tube PWM wave signal are also set to align with the emission position of the carrier signal, so their high level centers are also located at 0 microseconds.

[0050] Optionally, the preset conditions include:

[0051] The phase difference between the high level signal of the Q1 / Q3 inverter tube PWM wave and the high level signal of the Q2 / Q4 inverter tube PWM wave is 180 degrees;

[0052] For example, Figure 3 As shown, the phase difference between the high-level signal of the Q1 / Q3 inverter tube PWM wave and the high-level signal of the Q2 / Q4 inverter tube PWM wave is 180 degrees, which means that when the Q1 / Q3 inverter tube PWM wave is at a high level, the Q2 / Q4 inverter tube PWM wave should be at a low level, and vice versa.

[0053] The Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal both refer to the carrier signal period, and the Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal are complementary and have a dead zone;

[0054] For example, Figure 4 As shown, the PWM wave of the Q1 / Q3 inverter tube and the PWM wave of the S1 rectifier tube will not be at a high level at the same time, and will be staggered by a certain time, which is the dead time; the dead time is set to prevent the inverter tube and the rectifier tube from being turned on at the same time, causing a short circuit.

[0055] The Q1 / Q3 inverter tube PWM wave signal and the VT1 absorption tube PWM wave signal both refer to the carrier cycle, and the Q1 / Q3 inverter tube PWM wave signal and the VT1 absorption tube PWM wave signal are complementary, and there is no dead zone;

[0056] For example, Figure 4 As shown, the PWM wave of the Q1 / Q3 inverter tube and the PWM wave of the VT1 absorption tube will be at a high level at the same time, and will be staggered with each other, but there will be no dead time; this is because the main function of the absorption tube is to absorb the peak voltage generated when the rectifier tube is turned off, so it needs to be turned on immediately at the moment the rectifier tube is turned off, so there can be no dead time; when the high level of the Q1 / Q3 inverter tube PWM wave ends, the high level of the VT1 absorption tube PWM wave should start immediately to ensure that it can absorb the peak voltage generated when the rectifier tube S1 is turned off.

[0057] The Q2 / Q4 inverter tube PWM wave signal and the S2 rectifier tube PWM wave signal both refer to the carrier cycle, and the Q2 / Q4 inverter tube PWM wave signal and the S2 rectifier tube PWM wave signal are complementary, and there is a dead zone;

[0058] For example, Figure 5 As shown in the figure, the PWM wave of the Q2 / Q4 inverter tube and the PWM wave of the S2 rectifier tube will not be at a high level at the same time, and will be staggered for a certain period of time. This time is the dead time. The dead time is set to prevent the inverter tube and the rectifier tube from being turned on at the same time, causing a short circuit.

[0059] The Q2 / Q4 inverter tube PWM wave signal and the VT2 absorption tube PWM wave signal both refer to the carrier cycle, and the Q2 / Q4 inverter tube PWM wave signal and the VT2 absorption tube PWM wave signal are complementary to each other, and there is no dead zone.

[0060] For example, Figure 5 As shown, the PWM wave of the Q2 / Q4 inverter tube and the PWM wave of the VT2 absorption tube will be at a high level at the same time, and will be staggered with each other, but there will be no dead time; this is because the main function of the absorption tube is to absorb the peak voltage generated when the rectifier tube is turned off, so it needs to be turned on immediately at the moment the rectifier tube is turned off, so there can be no dead time; when the high level of the Q2 / Q4 inverter tube PWM wave ends, the high level of the VT2 absorption tube PWM wave should start immediately to ensure that it can absorb the peak voltage generated when the rectifier tube S2 is turned off.

[0061] Optionally, the method further comprises:

[0062] Initialize the CPU module of the chip;

[0063] Exemplarily, the CPU module of the chip is initialized, which usually includes configuring the CPU's basic clock, memory, interrupt system, etc. to ensure that the CPU can work normally; for example, turning on the CPU's clock source and configuring the clock frequency; configuring the CPU's memory area, including the data area, program area, etc.; configuring the interrupt system, setting the interrupt priority and interrupt handling function.

[0064] Set the carrier signal and the channels and switching states of the multiple PWM wave signals.

[0065] For example, the carrier signal serves as a reference for the other six PWM signals, and its setting is crucial; a certain channel (such as channel 1) can be selected as the channel of the carrier signal, and channels 2 to 7 can be set as output channels of multiple PWM wave signals respectively; then the switching states of multiple PWM wave signals are set, which includes determining the configuration frequency and duty cycle of each PWM signal, and setting their relationship with the carrier signal; setting a specific frequency and duty cycle for each PWM signal, and these values ​​are usually pre-calculated according to the needs of the DC-DC converter; according to the working mode of the DC-DC converter, the switching states of multiple PWM wave channels are adjusted to avoid direct passage of the upper and lower bridge arms at each stage.

[0066] Optionally, the wave-generating mode includes: a full-off mode, a full-wave-generating mode, a mode in which the inverter tube and the absorption tube generate waves and the rectifier tube does not generate waves, a mode in which the rectifier tube generates waves and the inverter tube and the absorption tube does not generate waves, and a mode in which the rectifier tube and the absorption tube generate waves and the inverter tube does not generate waves; wherein,

[0067] The fully closed mode is that the waveforms of the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all low level;

[0068] For example, Figure 6 As shown, all PWM wave signals are set to low level to ensure that the circuit is in a safe, non-working state; the carrier signal is output normally according to the cycle, and the Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT2 absorption tube PWM wave signal all output low level.

[0069] The full-wave mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions;

[0070] For example, Figure 7 As shown in the figure, the carrier signal is used as the reference of these multiple PWM wave signals. Its period and duty cycle will directly affect the wave transmission of other PWM wave signals. In the full wave transmission mode, the carrier signal will maintain a stable period and duty cycle to provide a stable reference for other PWM wave signals; Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT2 absorption tube PWM wave signal, these multiple PWM wave signals will be generated according to preset conditions (such as phase difference, duty cycle, period, etc.). These conditions have been set in the initialization stage and will be maintained in the full wave transmission mode. unchanged; for example, the high-level signals of the PWM wave signal of the Q1 / Q3 inverter tube and the PWM wave signal of the Q2 / Q4 inverter tube will have a fixed phase difference (usually 180 degrees) to ensure that the upper and lower bridge arms in the circuit will not pass directly; at the same time, each PWM wave signal will maintain a complementary relationship with its corresponding rectifier tube or absorption tube PWM wave signal (with or without dead zone) to ensure the normal operation of the circuit; in practical applications, the full-wave mode is usually used for the normal working state of the DC-DC converter. In this state, the DC-DC converter will adjust the duty cycle and period and other parameters of these multiple PWM wave signals according to the input DC voltage and the required output DC voltage to achieve precise voltage conversion and control.

[0071] The inverter tube absorption tube wave-generating and rectifier tube non-generating mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally generated and meet the preset conditions, and the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both low level;

[0072] For example, Figure 8 As shown, the PWM wave signal of the Q1 / Q3 inverter tube is in a normal state. It will be modulated according to the preset carrier cycle to ensure that it maintains a specific phase relationship with the carrier signal. In this mode, the Q1 / Q3 inverter tube will switch according to the duty cycle of the PWM signal and participate in the inverter process of the DC-DC converter; the PWM wave signal of the Q2 / Q4 inverter tube is also in a normal state, and maintains a phase difference of 180 degrees with the PWM wave signal of the Q1 / Q3 inverter tube, ensuring that the two groups of inverter tubes will not be turned on at the same time during the inverter process, thereby avoiding short circuit; the VT1 absorption tube PW The M wave signal maintains a specific phase relationship with the Q1 / Q3 inverter tube PWM wave signal, which is used to absorb the peak voltage generated when the Q1 / Q3 inverter tube is turned off to protect the stable operation of the circuit; the VT2 absorption tube PWM wave signal maintains a specific phase relationship with the Q2 / Q4 inverter tube PWM wave signal, which is used to absorb the peak voltage generated when the Q2 / Q4 inverter tube is turned off; the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal remain in a low level state, which means that the S1 rectifier tube and the S2 rectifier tube will not participate in the rectification process of the DC-DC converter and are in a closed state.

[0073] The rectifier tube wave-generating inverter tube absorption tube non-wave-generating mode is that the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both normally generated and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all low level;

[0074] For example, Fig. 9As shown in the figure, the PWM wave signal of the S1 rectifier tube is normally sent out according to the preset carrier period and duty cycle, and its waveform shows regular changes in high and low levels. In this mode, the S1 rectifier tube is responsible for rectifying the AC square wave voltage obtained from the secondary side of the transformer to obtain a DC square wave voltage; the PWM wave signal of the S2 rectifier tube is also normally sent out according to the preset carrier period and duty cycle, and maintains similar waveform characteristics to the PWM wave signal of the S1 rectifier tube. The S2 rectifier tube also participates in the rectification process to ensure the stability of the output DC voltage; in this mode, the PWM wave signals of the Q1, Q2, Q3, and Q4 inverter tubes all maintain a low level. state, does not participate in the switching action of the circuit, which means that the Q1, Q2, Q3, and Q4 inverter tubes are in the off state and will not provide AC square wave voltage to the primary side of the transformer; in this mode, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal also remain in a low level state; due to the normal rectifier tubes S1 and S2, spike voltages may be generated during the shutdown process, but since the VT1 absorption tube is in the off state, these spike voltages will not be absorbed; however, in actual applications, there are usually other mechanisms (such as capacitors, etc.) to absorb these spike voltages to protect the safe operation of the circuit.

[0075] The rectifier tube absorption tube generates waves and the inverter tube does not generate waves in the mode in which the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal are all low level.

[0076] For example, Fig.10 As shown, the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both sent out normally, they are modulated with reference to the carrier cycle and meet the preset waveform relationship (such as duty cycle, phase, etc.); the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are also sent out normally, they are also modulated with reference to the carrier cycle and meet the preset waveform relationship; the Q1 / Q3 inverter tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal remain in a low level state and do not participate in the current waveform output; the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal both send out waveforms normally, while the Q1 / Q3 inverter tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal remain in a low level state. At the same time, the complementary waveforms of the Q1 / Q3 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal, the complementary waveforms of the VT2 absorption tube PWM wave signal, also send out waveforms normally.

[0077] Optionally, inputting and updating the duty cycle value includes:

[0078] Enter a new duty cycle value;

[0079] The duty cycle values ​​of the multiple PWM wave signals are updated to new duty cycle values ​​in the next cycle.

[0080] Exemplarily, first, according to the output voltage requirement of the DC-DC converter, the required new duty cycle value is calculated, and this value can be obtained by table lookup, calculation or using an algorithm; the calculated new duty cycle value is input; wait for the current PWM cycle to end, and once the current cycle ends, the new duty cycle value will be updated at the beginning of the next cycle, thereby changing the duty cycle of the PWM wave; the duty cycle value is updated in the next cycle, ensuring that the PWM waveform in the current cycle is not affected, thereby avoiding instantaneous voltage fluctuations caused by sudden changes in the duty cycle, and ensuring the stability of the output voltage; the new duty cycle value takes effect at the beginning of the next cycle, providing a smooth transition process for the system, helping to reduce the system impact caused by duty cycle changes, and improving the stability and reliability of the system.

[0081] Optionally, outputting the updated multiple PWM wave signals according to the updated duty cycle value includes:

[0082] The updated plurality of PWM wave signals are outputted in a next cycle after the duty cycle values ​​of the plurality of PWM wave signals are updated;

[0083] The updated multiple PWM wave signals can meet the preset conditions.

[0084] For example, a new duty cycle value is input and the new duty cycle value is updated at the beginning of the next cycle; at the beginning of the next cycle after the duty cycle value is updated, the duty cycle of the PWM wave is updated according to the updated duty cycle value; since the update takes effect in the next cycle, instantaneous voltage fluctuations can be avoided to ensure stable operation of the system.

[0085] Optionally, the method further comprises:

[0086] The S1 rectifier tube, S2 rectifier tube, Q1 / Q3 inverter tube, and Q2 / Q4 inverter tube are controlled by registers of the same group but different channels;

[0087] The periods of the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal all refer to the period of the carrier signal.

[0088] Exemplarily, the use of register control in the same group but different channels and a periodic reference carrier signal can reduce the overall demand for register resources; since the registers are in the same group, the control logic can be more centralized and simplified, making it easier to manage and maintain; the S1 rectifier, S2 rectifier, Q1 / Q3 inverter, and Q2 / Q4 inverter use registers of different channels to avoid conflicts in control signals between different components and ensure stable operation of the system.

[0089] Based on the same inventive concept, Fig.11 As shown, the present invention provides a wave generation system of a DC-DC converter, the system comprising:

[0090] Initialization module, used to initialize the chip and set the carrier signal;

[0091] A PWM wave signal setting module is used to set a plurality of PWM wave signals respectively based on the carrier signal and preset conditions; the PWM wave signal setting module is also used to establish different wave transmission modes based on the plurality of PWM wave signals after setting;

[0092] A PWM wave signal generating module, used for inputting and updating a duty cycle value, and outputting updated multiple PWM wave signals according to the updated duty cycle value;

[0093] The control module is used to select the corresponding wave generation mode according to the updated multiple PWM wave signals to achieve control of the output voltage of the DC-DC converter.

[0094] Alternatively, if Fig.12 As shown, the PWM wave signal generating module includes:

[0095] The TOM submodule is used to monitor the time and trigger the update operation at the end of each carrier signal cycle;

[0096] A duty cycle shadow register, for receiving and storing a duty cycle value to be applied in the next carrier signal cycle;

[0097] A duty cycle register, used to store the duty cycle value actually used in the current carrier signal cycle; the duty cycle register is also used to receive the duty cycle value sent by the duty cycle shadow register before the start of each carrier signal cycle;

[0098] A cycle shadow register, used to receive and store a cycle value to be applied in the next carrier signal cycle;

[0099] A cycle register, used to store the cycle value actually used by the current carrier signal cycle; the cycle register is also used to receive the cycle value sent by the cycle shadow register before each carrier signal cycle starts;

[0100] The GTM submodule is used to generate the carrier signal; the GTM module is also used to read the duty cycle value in the duty cycle register and the period value in the period register at the beginning of each carrier signal cycle, and generate a PWM wave signal according to the read duty cycle value and period value.

[0101] It should be noted that the electrical connection between the above-mentioned units does not necessarily mean the connection between lines. An indirect connection method can be applied to the embodiments of the present invention as long as the purpose of the present invention is achieved.

[0102] The above is only an exemplary embodiment of the present invention and cannot be used to limit the scope of the present invention. That is, any equivalent changes and modifications made according to the teachings of the present invention are still within the scope of the present invention. After considering the disclosure of the specification and the truth of practice, it will be easy for those skilled in the art to think of other embodiments of the present invention. This application is intended to cover any variation, use or adaptive change of the present invention, which follows the general principles of the present invention and includes common knowledge or customary technical means in the technical field not recorded in the present invention.

Claims

1. A wave generation method for a DC-DC converter, characterized in that: The method comprises: Initialize the chip and set the carrier signal related parameters; Based on the carrier signal and preset conditions, the waveforms of multiple PWM wave signals output by the chip are respectively set; Based on the set multiple PWM wave signals, different wave generation modes are established; Inputting and updating the duty cycle value, and outputting the updated multiple PWM wave signals according to the updated duty cycle value; The corresponding wave generation mode is selected according to the updated multiple PWM wave signals to achieve control of the output voltage of the DC-DC converter.

2. A method for generating a wave of a DC-DC converter according to claim 1, characterized in that: The multiple PWM wave signals include: Q1 / Q3 inverter tube PWM wave signal, Q2 / Q4 inverter tube PWM wave signal, S1 rectifier tube PWM wave signal, S2 rectifier tube PWM wave signal, VT1 absorption tube PWM wave signal and VT2 absorption tube PWM wave signal; among them, The high level centers of the Q1 / Q3 inverter tube PWM wave signal, the S2 rectifier tube PWM wave signal and the VT2 absorption tube PWM wave signal all fall at the center position of the carrier signal; The high level centers of the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal and the VT1 absorption tube PWM wave signal all fall on the sending position of the carrier signal.

3. The method for generating a wave of a DC-DC converter according to claim 2, characterized in that: The preset conditions include: The phase difference between the high level signal of the Q1 / Q3 inverter tube PWM wave and the high level signal of the Q2 / Q4 inverter tube PWM wave is 180 degrees; The Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal both refer to the carrier signal period, and the Q1 / Q3 inverter tube PWM wave signal and the S1 rectifier tube PWM wave signal are complementary and have a dead zone; The Q1 / Q3 inverter tube PWM wave signal and the VT1 absorption tube PWM wave signal both refer to the carrier cycle, and the Q1 / Q3 inverter tube PWM wave signal and the VT1 absorption tube PWM wave signal are complementary, and there is no dead zone; The Q2 / Q4 inverter tube PWM wave signal and the S2 rectifier tube PWM wave signal both refer to the carrier cycle, and the Q2 / Q4 inverter tube PWM wave signal and the S2 rectifier tube PWM wave signal are complementary, and there is a dead zone; The Q2 / Q4 inverter tube PWM wave signal and the VT2 absorption tube PWM wave signal both refer to the carrier cycle, and the Q2 / Q4 inverter tube PWM wave signal and the VT2 absorption tube PWM wave signal are complementary to each other, and there is no dead zone.

4. The method for generating a wave of a DC-DC converter according to claim 1, characterized in that: The method further comprises: Initialize the CPU module of the chip; Set the carrier signal and the channels and switching states of the multiple PWM wave signals.

5. The method for generating a wave of a DC-DC converter according to claim 2, characterized in that: The wave-generating modes include: full-off mode, full-wave-generating mode, inverter tube absorption tube wave-generating mode and rectifier tube non-wave-generating mode, rectifier tube wave-generating mode and inverter tube absorption tube non-wave-generating mode, rectifier tube absorption tube wave-generating mode and inverter tube non-wave-generating mode; wherein, The fully closed mode is that the waveforms of the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all low level; The full-wave mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions; The inverter tube absorption tube wave-generating and rectifier tube non-generating mode is that the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally generated and meet the preset conditions, and the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both low level; The rectifier tube wave-generating inverter tube absorption tube non-wave-generating mode is that the S1 rectifier tube PWM wave signal and the S2 rectifier tube PWM wave signal are both normally generated and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all low level; The rectifier tube absorption tube generates waves and the inverter tube does not generate waves in the mode in which the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal are all normally emitted and meet the preset conditions, and the Q1 / Q3 inverter tube PWM wave signal and the Q2 / Q4 inverter tube PWM wave signal are all low level.

6. The method for generating a wave of a DC-DC converter according to claim 1, characterized in that: The inputting and updating of the duty cycle value comprises: Enter a new duty cycle value; The duty cycle values ​​of the multiple PWM wave signals are updated to new duty cycle values ​​in the next cycle.

7. The method for generating a wave of a DC-DC converter according to claim 1, characterized in that: Outputting the updated plurality of PWM wave signals according to the updated duty cycle value comprises: The updated plurality of PWM wave signals are outputted in a next cycle after the duty cycle values ​​of the plurality of PWM wave signals are updated; The updated multiple PWM wave signals can meet the preset conditions.

8. The method for generating a wave of a DC-DC converter according to claim 2, characterized in that: The method comprises: The S1 rectifier tube, S2 rectifier tube, Q1 / Q3 inverter tube, and Q2 / Q4 inverter tube are controlled by registers of the same group but different channels; The periods of the Q1 / Q3 inverter tube PWM wave signal, the Q2 / Q4 inverter tube PWM wave signal, the S1 rectifier tube PWM wave signal, the S2 rectifier tube PWM wave signal, the VT1 absorption tube PWM wave signal and the VT2 absorption tube PWM wave signal all refer to the period of the carrier signal.

9. A wave generating system of a DC-DC converter, characterized in that: The system comprises: Initialization module, used to initialize the chip and set the carrier signal; A PWM wave signal setting module is used to set a plurality of PWM wave signals respectively based on the carrier signal and preset conditions; the PWM wave signal setting module is also used to establish different wave transmission modes based on the plurality of PWM wave signals after setting; A PWM wave signal generating module, used for inputting and updating a duty cycle value, and outputting updated multiple PWM wave signals according to the updated duty cycle value; The control module is used to select the corresponding wave generation mode according to the updated multiple PWM wave signals to achieve control of the output voltage of the DC-DC converter.

10. A DC-DC converter wave generating system according to claim 9, characterized in that: The PWM wave signal generating module comprises: The TOM submodule is used to monitor the time and trigger the update operation at the end of each carrier signal cycle; A duty cycle shadow register, for receiving and storing a duty cycle value to be applied in the next carrier signal cycle; A duty cycle register, used to store the duty cycle value actually used in the current carrier signal cycle; the duty cycle register is also used to receive the duty cycle value sent by the duty cycle shadow register before the start of each carrier signal cycle; A cycle shadow register, used to receive and store a cycle value to be applied in the next carrier signal cycle; A cycle register, used to store the cycle value actually used by the current carrier signal cycle; the cycle register is also used to receive the cycle value sent by the cycle shadow register before each carrier signal cycle starts; The GTM submodule is used to generate the carrier signal; the GTM module is also used to read the duty cycle value in the duty cycle register and the period value in the period register at the beginning of each carrier signal cycle, and generate a PWM wave signal according to the read duty cycle value and period value.

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