Voltage stabilizer based on alternating current-alternating current direct signal conversion and signal conversion method thereof

Abstract

The invention discloses a voltage stabilizer based on alternating current-alternating current direct signal conversion and a signal conversion method thereof. The voltage stabilizer based on alternating current-alternating current direct signal conversion comprises at least one master control switch, a first rectification branch and a second rectification branch. The master control switch is used for controlling the output voltage based on the duty ratio; the first rectification branch is connected in series with the master control switch and comprises a first diode and a first branch switch which are connected in series and further comprises a first capacitor, one end of the first capacitor is connected between the first diode and the first branch switch, and the other end of the first capacitor is grounded; the second rectification branch is connected with the first rectification branch in parallel and comprises a second diode and a second branch switch which are connected in series and further comprises a second capacitor, one end of the second capacitor is connected between the second diode and the second branch switch, and the other end of the second capacitor is grounded. Therefore, the voltage stabilizer can realize direct alternating current-alternating current signal conversion, simplifies a signal conversion device and a signal conversion process, and improves conversion efficiency and reliability.

Description

Technical Field

[0001] This application relates to the field of voltage regulator control, specifically to a voltage regulator based on AC-AC direct signal conversion and its signal conversion method. Background Technology

[0002] The AC voltage in the power grid often fluctuates due to factors such as load changes and line losses. This unstable power supply quality can threaten the normal operation, lifespan, and safety of various sensitive electrical equipment. Therefore, voltage regulators, as key power electronic devices, play a vital role in industrial production, scientific research experiments, and daily life by converting and regulating input AC signals to provide stable and high-quality AC power to the load. Constructing an efficient and reliable AC-AC signal conversion scheme is the core requirement of voltage regulator design.

[0003] Currently, traditional AC voltage regulation technologies typically employ an indirect AC-DC-AC conversion architecture. This architecture first converts the input AC power into DC power through a rectification stage, storing it in an intermediate DC stage (usually a large-capacity electrolytic capacitor). Then, an inverter stage converts this DC power back into a stable AC output with controllable amplitude and frequency. However, this indirect conversion architecture has inherent drawbacks: First, the presence of two main power conversion stages—AC-DC rectification and DC-AC inversion—increases the overall system complexity, requiring more power semiconductor devices and control circuits, thus increasing manufacturing costs and equipment size. Second, the energy undergoes two conversions, with power losses inevitable at each stage, resulting in low overall system efficiency. Furthermore, the large-capacity energy storage capacitor required for the intermediate DC stage is not only bulky but also a weak point with a high system failure rate, affecting the long-term reliability of the voltage regulator. Therefore, developing a direct AC-AC signal conversion technology that simplifies the circuit structure and improves conversion efficiency and reliability has become an important research direction in the industry. Summary of the Invention

[0004] One advantage of this application is that it provides a voltage regulator based on AC-AC direct signal conversion and a signal conversion method thereof. The voltage regulator based on AC-AC direct signal conversion can realize direct AC-AC signal conversion, simplifying the signal conversion device and process, and improving conversion efficiency and reliability.

[0005] According to one aspect of this application, a voltage regulator based on AC-AC direct signal conversion is provided, comprising:

[0006] At least one master control switch is used to control its output voltage based on the duty cycle; The first rectifier branch is connected in series with the main control switch and includes a first diode and a first branch switch connected in series. It also includes a first capacitor, wherein one end of the first capacitor is connected between the first diode and the first branch switch, and the other end is grounded. The second rectifier branch, connected in parallel with the first rectifier branch, includes a second diode and a second branch switch connected in series, and a second capacitor, wherein one end of the second capacitor is connected between the second diode and the second branch switch, and the other end is grounded.

[0007] In one embodiment of the voltage regulator based on AC-AC direct signal conversion according to this application, the first rectifier branch and the second rectifier branch are configured to be switched on in turn.

[0008] In one embodiment of the voltage regulator based on AC-AC direct signal conversion according to this application, the electrodes of the first diode and the second diode are connected in opposite directions.

[0009] In one embodiment of the voltage regulator based on AC-AC direct signal conversion according to this application, at least one main control switch includes a first main control switch and a second main control switch connected in series.

[0010] In one embodiment of the voltage regulator based on AC-AC direct signal conversion according to this application, the voltage regulator based on AC-AC direct signal conversion further includes a low-pass filter connected to the first rectifier branch and the second rectifier branch, the low-pass filter being an LC inductor filter.

[0011] According to another aspect of this application, an AC-AC direct signal conversion method for a voltage regulator is provided, comprising: Control the duty cycle of the first AC signal output by at least one master control switch; Based on the positive or negative sign of the first AC signal, the first rectifier branch or the second rectifier branch is controlled to rectify the first AC signal to output the second AC signal; The first rectifier branch is connected in series with the main control switch, including a first diode and a first branch switch connected in series, and a first capacitor, wherein one end of the first capacitor is connected between the first diode and the first branch switch, and the other end is grounded; The second rectifier branch is connected in parallel with the first rectifier branch. It includes a second diode and a second branch switch connected in series, and a second capacitor. One end of the second capacitor is connected between the second diode and the second branch switch, and the other end is grounded.

[0012] In one embodiment of the AC-AC direct signal conversion method for a voltage regulator according to this application, controlling a first rectifier branch or a second rectifier branch to rectify the first AC signal based on the positive or negative sign of the first AC signal to output a second AC signal includes: in response to the first AC signal being in the positive half-cycle, controlling the first rectifier branch to perform preliminary rectification of the first AC signal to form the positive half-cycle portion of the pre-filtered modulation signal, and then controlling a low-pass filter to filter the positive half-cycle portion of the pre-filtered modulation signal to output the positive half-cycle portion of the second AC signal; or, in response to the first AC signal being in the negative half-cycle, controlling the second rectifier branch to perform preliminary rectification of the first AC signal to form the negative half-cycle portion of the pre-filtered modulation signal, and then controlling a low-pass filter to filter the negative half-cycle portion of the pre-filtered modulation signal to output the negative half-cycle portion of the second AC signal.

[0013] In one embodiment of the AC-AC direct signal conversion method for a voltage regulator according to this application, the anode of a first diode is connected to a main control switch, and the cathode is connected to a first branch switch; the cathode of a second diode is connected to a main control switch, and the anode is connected to a second branch switch; in response to the first AC signal being in the positive half-cycle, controlling the first rectifier branch to perform preliminary rectification of the first AC signal to form the positive half-cycle portion of the pre-filtered modulation signal includes: in response to the first AC signal being in the positive half-cycle, controlling the first branch switch to be turned on and the second branch switch to be turned off, so that the first branch rectifier branch performs preliminary rectification of the first AC signal; in response to the first AC signal being in the negative half-cycle, controlling the second rectifier branch to perform preliminary rectification of the first AC signal to form the negative half-cycle portion of the pre-filtered modulation signal includes: in response to the first AC signal being in the negative half-cycle, controlling the second branch switch to be turned on and the first branch switch to be turned off, so that the second branch rectifier branch performs preliminary rectification of the first AC signal.

[0014] In one embodiment of the AC-AC direct signal conversion method for a voltage regulator according to this application, a controller controls the first branch switch and the second branch switch. The controller is further configured to receive a periodic positive / negative flag signal, a standard sinusoidal reference signal, and a high-frequency triangular wave carrier signal representing the positive / negative nature of the first AC signal. The control signals for the first branch switch and the second branch switch are both sinusoidal pulse width modulation (PWM) signals, wherein the duty cycle of the PWM signal varies sinusoidally. In response to the first AC signal being in its positive half-cycle, the first branch switch is controlled... The first branch switch is turned on and the second branch switch is turned off, including: generating a sinusoidal pulse width modulation signal for controlling the first branch switch in response to the first AC signal being in the positive half-cycle and the absolute value of the voltage of the standard sinusoidal reference signal being greater than the absolute value of the voltage of the high-frequency triangular wave carrier signal; controlling the second branch switch to turn on and the first branch switch to turn off in response to the first AC signal being in the positive half-cycle, including: generating a sinusoidal pulse width modulation signal for controlling the first branch switch in response to the first AC signal being in the positive half-cycle and the absolute value of the voltage of the standard sinusoidal reference signal being less than the absolute value of the voltage of the high-frequency triangular wave carrier signal.

[0015] The further objectives and advantages of this application will become fully apparent from the following description and accompanying drawings. Attached Figure Description

[0016] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0017] Figure 1 The figure shows a circuit diagram of a voltage regulator based on AC-AC direct signal conversion and its signal conversion method according to an embodiment of this application.

[0018] Figure 2 The figure shows a flowchart of an AC-AC direct signal conversion method for a voltage regulator according to an embodiment of the present application. Detailed Implementation

[0019] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein.

[0020] It is understood that the term "a" should be understood as "at least one" or "one or more," meaning that in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. The term "a" should not be construed as a limitation on the quantity. "Multiple" means two or more.

[0021] While ordinal numbers such as “first,” “second,” etc., will be used to describe various components, there is no limitation on those components herein. The term is used only to distinguish one component from another; for example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component, without departing from the teachings of this application. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0022] The terminology used herein is for the purpose of describing various embodiments only and is not intended to be limiting. As used herein, the singular form also includes the plural form, unless the context clearly indicates otherwise. It will also be understood that the terms “comprising” and / or “having” as used in this specification specify the presence of the described features, numbers, operations, components, elements or combinations thereof, without excluding the presence or addition of one or more other features, numbers, operations, components, elements or combinations thereof.

[0023] As mentioned above, traditional techniques for AC voltage regulation typically employ an indirect AC-DC-AC conversion architecture. This architecture first converts the input AC power into DC power through a rectifier, storing it in an intermediate DC link (usually a large-capacity electrolytic capacitor). Then, an inverter converts this DC power back into a stable AC power output with controllable amplitude and frequency. However, this indirect conversion architecture has inherent drawbacks.

[0024] Based on this, this application abandons the traditional indirect AC-DC-AC conversion architecture and instead adopts a direct AC-AC conversion topology. Specifically, a master control switch is used to perform high-frequency chopping on the input AC signal to achieve basic adjustment of the output voltage amplitude. More importantly, the subsequent circuit is innovatively designed with two parallel and complementary rectifier branches. The first rectifier branch is specifically responsible for processing the positive half-cycle of the AC signal, while the second rectifier branch is specifically responsible for processing the negative half-cycle. By precisely and selectively activating the corresponding rectifier branch according to the real-time polarity of the input AC signal, the duty cycle modulated signal is half-wave rectified, ultimately combining into a complete, stable, and continuous AC waveform at the output.

[0025] By eliminating the traditional intermediate DC energy storage stage and the corresponding rectifier-inverter power conversion stages, this scheme directly processes and reconstructs the AC signal, significantly simplifying the overall system circuit structure and reducing the number of power devices required. This structural simplification directly translates into lower manufacturing costs, smaller device size, and higher power density. Simultaneously, the shortened energy conversion path avoids the cumulative losses caused by multi-stage conversion, effectively improving the system's energy conversion efficiency. Furthermore, eliminating the large-capacity electrolytic capacitor, a weak point in traditional schemes, fundamentally enhances the long-term operational reliability and lifespan of the voltage regulator.

[0026] Specifically, such as Figure 1 and Figure 2 As shown, a voltage regulator based on AC-AC direct signal conversion and its signal conversion method according to an embodiment of this application are illustrated. The voltage regulator based on AC-AC direct signal conversion includes at least one main control switch, a first rectifier branch 20, and a second rectifier branch 30. The main control switch is used to control its output voltage based on the duty cycle; the first rectifier branch 20 is connected in series with the main control switch and includes a first diode 21 and a first branch switch 22 connected in series, and also includes a first capacitor 23, wherein one end of the first capacitor 23 is connected between the first diode 21 and the first branch switch 22, and the other end is grounded; the second rectifier branch 30 is connected in parallel with the first rectifier branch 20 and includes a second diode 31 and a second branch switch 32 connected in series, and also includes a second capacitor 33, wherein one end of the second capacitor 33 is connected between the second diode 31 and the second branch switch 32, and the other end is grounded.

[0027] More specifically, the master control switch is a semiconductor power device, which can be implemented as a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or an IGBT (Insulated-Gate Bipolar Transistor), and can be controlled by a weak electrical signal to switch between on and off at an extremely high speed, reaching thousands to hundreds of thousands of times per second (i.e., at the kHz level). The signal controlling the master control switch is an AC signal. Accordingly, the signal output by the master control switch is also an AC signal, defined as the first AC signal.

[0028] The number of the main control switches is set according to the requirements. In one embodiment of this application, the voltage regulator based on AC-AC direct signal conversion includes only one main control switch. In other embodiments of this application, the voltage regulator based on AC-AC direct signal conversion may include two main control switches (e.g., a first main control switch 10 and a second main control switch 60 connected in series), or more than two main control switches.

[0029] Both the first diode 21 and the second diode 31 are semiconductor power devices, which can be implemented as MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) or IGBTs (Insulated-Gate Bipolar Transistors). The electrodes of the first diode 21 and the second diode 31 are connected in opposite directions. For example, the anode of the first diode 21 is connected to the main control switch, and the cathode is connected to the voltage output terminal; the anode of the second diode 31 is connected to the voltage output terminal, and the cathode is connected to the main control switch.

[0030] The first rectifier branch 20 and the second rectifier branch 30 are configured to be switched on and off, wherein the second rectifier branch 30 is disconnected when the first rectifier branch 20 is switched on, and the first rectifier branch 20 is disconnected when the second rectifier branch 30 is switched on.

[0031] When the first AC signal output by the main control switch is in the positive half-cycle, the first branch switch 22 is turned on, causing the first rectifier branch 20 to be turned on, thereby causing the first rectifier branch 20 to rectify the first AC signal in the positive half-cycle to output the positive half-cycle portion of the second AC signal; when the first AC signal is in the negative half-cycle, the second branch switch 32 is turned on, causing the second rectifier branch 30 to be turned on, thereby causing the second rectifier branch 30 to rectify the second AC signal in the negative half-cycle to output the negative half-cycle portion of the second AC signal.

[0032] Specifically, the on / off state and duty cycle of the main control switch, the first branch switch 22, and the second branch switch 32 can be precisely controlled by a controller 50, such as a microcontroller (MCU) or a digital signal processor (DSP). Accordingly, the main control switch, the first branch switch 22, and the second branch switch 32 are each connected to a controller 50.

[0033] In one embodiment of this application, the voltage regulator based on AC-AC direct signal conversion further includes a low-pass filter 40 connected to the first rectifier branch 20 and the second rectifier branch 30. The low-pass filter 40 can be implemented as an LC inductor filter. Specifically, as... Figure 1 As shown in one example of this application, the low-pass filter 40 includes a filter inductor 41 and a filter capacitor 42. The filter inductor 41 is connected in series with the first rectifier branch 20 and the second rectifier branch 30, with one end connected to the output terminal of the first rectifier branch 20 and the second rectifier branch 30, and the other end connected to the voltage output terminal.

[0034] Accordingly, the first AC signal in the positive half-cycle is initially rectified by the first rectifier branch 20 to form the positive half-cycle portion of the pre-filtered modulation signal; the positive half-cycle portion of the pre-filtered modulation signal is filtered by the low-pass filter 40 to form the positive half-cycle portion of the second AC signal; the first AC signal in the negative half-cycle is initially rectified by the second rectifier branch 30 to form the negative half-cycle portion of the pre-filtered modulation signal; the negative half-cycle portion of the pre-filtered modulation signal is filtered by the low-pass filter 40 to form the negative half-cycle portion of the second AC signal.

[0035] It is worth mentioning that for the positive and negative half-cycle signals of the second AC signal, it is necessary to suppress waveform crossover distortion at the zero-crossing point. That is, when hard switching is performed based on the periodicity, the output voltage will experience a step jump or a brief dead zone at the moment of alternation between the positive and negative half-cycles. This will seriously affect the quality of the output AC power, introduce high-order harmonics, and damage precision loads. In other words, at any given time, the output voltage is either equal to the discharge voltage of the first capacitor 23 or the discharge voltage of the second capacitor 33. This means that if the discharge voltage of the first capacitor 23 is not exactly zero at 180° during the zero-crossing switching, and the system switches to the branch of the second capacitor 33, the initial output of the discharge voltage of the second capacitor 33 will also not be exactly zero, resulting in a voltage jump and crossover distortion.

[0036] Therefore, this application introduces active waveform synthesis based on sinusoidal pulse width modulation (SPWM), upgrading the process of applying capacitor voltage to the load from a passive process determined by branch on / off states to an active, high-frequency modulated waveform synthesis process. Here, SPWM generates a pulse sequence with a width varying sinusoidally by comparing a sinusoidal reference signal with a high-frequency triangular carrier wave. Its core idea is the principle of area equivalence—within the same time interval, rectangular pulses of different widths with the same area have equivalent average effects on the load. After the pulse sequence is filtered by LC, an AC voltage close to an ideal sinusoidal voltage can be reconstructed.

[0037] Correspondingly, the core of sinusoidal pulse width modulation is area equivalence, that is, within the high-frequency switching cycle Tc, by controlling the on-time Ton of the switch, the average value of the output voltage can be controlled. This average value is proportional to the DC input voltage Vdc and the duty cycle (D=Ton / Tc), and the average output voltage Vavg=D within the switching cycle. Vdc, while for SPWM, the duty cycle D is set to change sinusoidally with time.

[0038] First, VC1 is set as the voltage of the first capacitor 23, serving as the DC bus voltage for the positive half-cycle; VC2 is set as the voltage of the second capacitor 33, serving as the DC bus voltage for the negative half-cycle; Pflag is a periodicity flag signal representing the first AC signal; Vrefsin is a standard sinusoidal reference signal, whose amplitude corresponds to the target output voltage, and whose frequency is the mains frequency (50Hz in China); and Vcarriertri is a high-frequency triangular wave carrier signal. Here, the capacitor voltage after passive switching is not directly used as the output, but rather regarded as a pseudo-DC source within the half-cycle to actively obtain a precise sinusoidal waveform using high-frequency sinusoidal pulse width modulation technology, thereby ensuring a smooth transition between half-cycles.

[0039] Standard sinusoidal reference signal (modulated wave) voltage value Vrefsin=Vm sin(ωm t), where Vm is the amplitude of the modulating wave, which determines the amplitude of the final output AC current; ωm is the angular frequency of the modulating wave, which determines the frequency of the output AC current (e.g., ωm=2). π 50 rad / s). The amplitude of the high-frequency triangular wave carrier signal voltage Vcarriertri is Vc, and the frequency is ωc, and ωc is much greater than ωm (ωc >> ωm).

[0040] Then, the absolute value of Vrefsin is continuously compared with the absolute value of Vcarriertri. If the absolute value of Vrefsin is greater than the absolute value of Vcarriertri, a high-level pulse is generated; if the absolute value of Vrefsin is less than the absolute value of Vcarriertri, a low-level pulse is generated. This process generates the original sinusoidal pulse width modulation signal Spwmraw, whose duty cycle varies sinusoidally, in real time. That is, the instantaneous duty cycle D(t) is calculated as:

[0041] Among them, the definition To regulate the modulation, in practical applications, to avoid overmodulation, a setting is usually set. .

[0042] Accordingly, the controller 50 is also configured to receive a periodic positive / negative flag signal Pflag, a standard sinusoidal reference signal Vrefsin, and a high-frequency triangular wave carrier signal Vcarriertri, representing the positive or negative nature of the first AC signal. The amplitude Vm of the standard sinusoidal reference signal Vrefsin can be adjusted by the controller 50.

[0043] Then, Pflag is used to gating Spwmraw. When Pflag is high (positive half-cycle), Spwmraw is assigned to the control signal Spwm1 of the first branch switch 22, and the control signal Spwm2 of the second branch switch 32 is set to low level (off). When Pflag is low (negative half-cycle), Spwmraw is assigned to the control signal Spwm2 of the second branch switch 32, and the control signal Spwm1 of the first branch switch 22 is set to low level (off).

[0044] Thus, during the positive half-cycle of the first AC signal, the high-frequency Spwm1 drives the first branch switch 22 to switch on and off rapidly, outputting the energy of VC1 in pulse form. The width (duty cycle) of these pulses follows a sinusoidal law, thereby forming the positive half-cycle portion of the pre-filter modulation signal V2acprefilter at the output. During the negative half-cycle, the high-frequency Spwm2 drives the second branch switch 32 to switch on and off rapidly, outputting the energy of VC2 in pulse form, forming the negative half-cycle portion of the pre-filter modulation signal V2acprefilter. Since the value of Vrefsin approaches zero near 0° and 180° (i.e., zero crossings), the width of the SPWM pulses generated at these moments also approaches zero.

[0045] Finally, the pre-filtered modulation signal V2acprefilter is passed through a low-pass filter 40 (usually an LC filter composed of an inductor and a capacitor; in practical applications, the load of the voltage regulator itself also has a filtering effect) to filter out the high-frequency components of Vcarriertri frequency, retaining only its low-frequency envelope, i.e., the fundamental component represented by V_ref_sin, to obtain a smooth and continuous second AC signal.

[0046] That is, within one switching cycle, the average value of the output voltage, Vavg(t), is: Positive half-cycle (0≤ωm) t≤π): At this time When Pflag is positive and high, the first branch is active, with an input voltage of VC1. Vavg(t) = D(t) VC1=(M VC1) sin(ωm t); Negative half-cycle (π<ωm) t≤2π): At this time When the value is negative, Pflag is low, the second branch operates, and its input voltage is VC2. The calculated value of D(t) is negative, but physically the duty cycle cannot be negative. The control logic uses a comparison... The absolute value of Vcarriertri(t) is used to generate a pulse, which is then applied to the second rectifier branch 30 that can generate a negative voltage. Therefore, the average output voltage is Vavg(t) = D(t). VC2=(M VC2) sin(ωm (t). Here, we can assume that the values ​​of VC1 and VC2 are approximately equal and stable, both being DC bus voltages.

[0047] After passing through the low-pass filter 40, the high-frequency carrier component is filtered out, and the output second AC signal will be very close to Vavg(t)≈(M). Vdcbus) sin(ωm t), where Vdcbus is the DC bus voltage mentioned above.

[0048] This achieves a smooth zero-crossing transition for the second AC signal, that is, from the formula D(t)=M sin(ωm It can be seen that at zero-crossing moments such as t=0 and t=π / ωm, sin(ωm) The value of t) is zero, so the instantaneous duty cycle D(t) is also zero. This means that the on-time of the switch is zero at the beginning and end of the half-cycle, and the output voltage naturally starts from zero or smoothly drops to zero, fundamentally eliminating crossover distortion.

[0049] Furthermore, since SPWM pushes harmonic components to the high-frequency band centered on the carrier frequency ωc, these high-frequency harmonics are easily filtered out by small-sized LC filters, resulting in a very pure fundamental frequency (50 / 60Hz) at the final output, extremely low total harmonic distortion (THD), and greatly improved output power quality.

[0050] In addition, due to the amplitude of the final output voltage (M) The amplitude Vm of the reference signal is proportional to the modulation index M. By precisely adjusting the amplitude Vm of the reference signal through a microcontroller 50 (MCU) or a digital signal processor (DSP), M can be quickly and accurately adjusted, thereby achieving precise dynamic closed-loop control of the output voltage and achieving excellent voltage regulation.

[0051] Based on the structure and working principle of the voltage regulator based on AC-AC direct signal conversion, as follows: Figure 2As shown, this application proposes an AC-AC direct signal conversion method for a voltage regulator, which includes: S1, controlling the duty cycle of a first AC signal output by at least one main control switch; S2, controlling a first rectifier branch 20 or a second rectifier branch 30 to rectify the first AC signal based on the positive or negative sign of the first AC signal to output a second AC signal.

[0052] In step S1, the duty cycle of the first AC signal output by at least one master control switch is controlled. Specifically, the duty cycle of the first AC signal output by at least one master control switch is controlled by controller 50. The duty cycle of the first AC signal affects the average output voltage of controller 50, and thus affects the average output voltage of the voltage regulator.

[0053] In step S2, the first rectifier branch 20 or the second rectifier branch 30 is controlled to rectify the first AC signal based on the positive or negative sign of the first AC signal to output a second AC signal. Specifically, in one embodiment of this application, in response to the first AC signal being in the positive half-cycle, the first rectifier branch 20 is controlled to rectify the first AC signal to form the positive half-cycle portion of the second AC signal; in response to the first AC signal being in the negative half-cycle, the second rectifier branch 30 is controlled to rectify the first AC signal to form the negative half-cycle portion of the second AC signal.

[0054] In one embodiment of this application, in response to the first AC signal being in the positive half-cycle, the first rectifier branch 20 is controlled to perform preliminary rectification on the first AC signal to form the positive half-cycle portion of the pre-filtered modulation signal, and then the low-pass filter 40 is controlled to filter the positive half-cycle portion of the pre-filtered modulation signal to output the positive half-cycle portion of the second AC signal. Alternatively, in response to the first AC signal being in the negative half-cycle, the second rectifier branch 30 is controlled to perform preliminary rectification on the first AC signal to form the negative half-cycle portion of the pre-filtered modulation signal, and then the low-pass filter 40 is controlled to filter the negative half-cycle portion of the pre-filtered modulation signal to output the negative half-cycle portion of the second AC signal.

[0055] More specifically, in response to the first AC signal being in the positive half-cycle, the first branch switch 22 is turned on and the second branch switch 32 is turned off, so that the first branch rectifier branch performs preliminary rectification of the first AC signal; in response to the first AC signal being in the negative half-cycle, the second branch switch 32 is turned on and the first branch switch 22 is turned off, so that the second branch rectifier branch performs preliminary rectification of the first AC signal.

[0056] In one embodiment of this application, the control signals for controlling the first branch switch 22 and the second branch switch 32 are both sinusoidal pulse width modulation (PWM) signals, wherein the duty cycle of the PWM signal varies according to a sinusoidal law. The PWM signals controlling the first branch switch 22 and the second branch switch 32 are mainly output based on the sign of the first AC signal and the comparison between the absolute voltage value of the standard sinusoidal reference signal and the absolute voltage value of the high-frequency triangular wave carrier signal.

[0057] In response to the first AC signal being in its positive half-cycle and the absolute value of the standard sinusoidal reference signal being greater than the absolute value of the high-frequency triangular wave carrier signal, a sinusoidal pulse width modulation (PWM) signal is generated to control the duty cycle of the first branch switch 22 to change sinusoidally. In response to the first AC signal being in its positive half-cycle and the absolute value of the standard sinusoidal reference signal being less than the absolute value of the high-frequency triangular wave carrier signal, a sinusoidal pulse width modulation (PWM) signal is generated to control the duty cycle of the first branch switch 22 to change sinusoidally.

[0058] In summary, the voltage regulator based on direct AC-AC signal conversion and its signal conversion method have been elucidated. The voltage regulator based on direct AC-AC signal conversion and its signal conversion method can achieve direct AC-AC signal conversion, simplifying the signal conversion device and process, and improving conversion efficiency and reliability.

[0059] The present application and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present application. The actual structure is not limited to this. In conclusion, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the spirit of the present application, such design should fall within the protection scope of the present application.

Claims

1. A regulated power supply based on AC-AC direct signal conversion, characterized by include: At least one master control switch is used to control its output voltage based on the duty cycle; The first rectifier branch is connected in series with the main control switch and includes a first diode and a first branch switch connected in series. It also includes a first capacitor, wherein one end of the first capacitor is connected between the first diode and the first branch switch, and the other end is grounded. The second rectifier branch, connected in parallel with the first rectifier branch, includes a second diode and a second branch switch connected in series, and a second capacitor, wherein one end of the second capacitor is connected between the second diode and the second branch switch, and the other end is grounded.

2. The AC-AC direct signal conversion based regulator according to claim 1, characterized in that, The first and second rectifier branches are configured to be switched on and off.

3. The AC-AC direct signal conversion based regulator according to claim 2, characterized in that, The electrodes of the first diode and the second diode are connected in opposite directions.

4. The AC-AC direct signal conversion based regulator of claim 1, wherein, At least one master control switch includes a first master control switch and a second master control switch connected in series.

5. The AC-AC direct signal conversion based regulator according to claim 3, characterized in that, The voltage regulator based on AC-AC direct signal conversion further includes a low-pass filter connected to the first rectifier branch and the second rectifier branch, wherein the low-pass filter is an LC inductor filter.

6. An AC-AC direct signal conversion method for a voltage regulator, characterized by, include: Control the duty cycle of the first AC signal output by at least one master control switch; Based on the positive or negative sign of the first AC signal, the first rectifier branch or the second rectifier branch is controlled to rectify the first AC signal to output the second AC signal; The first rectifier branch is connected in series with the main control switch, including a first diode and a first branch switch connected in series, and a first capacitor, wherein one end of the first capacitor is connected between the first diode and the first branch switch, and the other end is grounded; The second rectifier branch is connected in parallel with the first rectifier branch. It includes a second diode and a second branch switch connected in series, and a second capacitor. One end of the second capacitor is connected between the second diode and the second branch switch, and the other end is grounded.

7. The AC-AC direct signal conversion method for a voltage regulator according to claim 6, characterized in that, Controlling a first rectifier branch or a second rectifier branch to rectify the first AC signal based on the positive or negative sign of the first AC signal to output a second AC signal includes: responding to the first AC signal being in the positive half-cycle, controlling the first rectifier branch to perform preliminary rectification of the first AC signal to form the positive half-cycle portion of the pre-filtered modulation signal, and then controlling a low-pass filter to filter the positive half-cycle portion of the pre-filtered modulation signal to output the positive half-cycle portion of the second AC signal; or, responding to the first AC signal being in the negative half-cycle, controlling the second rectifier branch to perform preliminary rectification of the first AC signal to form the negative half-cycle portion of the pre-filtered modulation signal, and then controlling a low-pass filter to filter the negative half-cycle portion of the pre-filtered modulation signal to output the negative half-cycle portion of the second AC signal.

8. The AC-AC direct signal conversion method for a voltage regulator according to claim 7, characterized in that, The positive terminal of the first diode is connected to the main control switch, and the negative terminal is connected to the first branch switch; the negative terminal of the second diode is connected to the main control switch, and the positive terminal is connected to the second branch switch. In response to the first AC signal being in the positive half-cycle, controlling the first rectifier branch to perform preliminary rectification on the first AC signal to form the positive half-cycle portion of the pre-filtered modulation signal includes: in response to the first AC signal being in the positive half-cycle, controlling the first branch switch to be turned on and the second branch switch to be turned off, so that the first branch rectifier branch performs preliminary rectification on the first AC signal. In response to the first alternating current signal being in a negative half cycle, the second rectification branch is controlled to perform preliminary rectification on the first alternating current signal to form a negative half cycle part of the pre-filtered modulation signal, including: in response to the first alternating current signal being in a negative half cycle, the second branch switch is controlled to be turned on and the first branch switch is controlled to be turned off, so that the second branch rectification branch performs preliminary rectification on the first alternating current signal.

9. The AC-AC direct signal conversion method for a voltage regulator according to claim 8, characterized in that, The controller is further configured to receive a cycle polarity flag signal representing the positive and negative of the first alternating current signal, a standard sine reference signal, and a high-frequency triangular wave carrier signal. The control signals for controlling the first branch switch and the second branch switch are both sine pulse width modulation signals, and the duty cycles of the sine pulse width modulation signals change according to a sine law. In response to the first alternating current signal being in a positive half cycle, the first branch switch is controlled to be turned on and the second branch switch is controlled to be turned off, including: in response to the first alternating current signal being in a positive half cycle, and the absolute value of the voltage of the standard sine reference signal being greater than the absolute value of the voltage of the high-frequency triangular wave carrier signal, a sine pulse width modulation signal for controlling the first branch switch is generated. In response to the first alternating current signal being in a positive half cycle, the second branch switch is controlled to be turned on and the first branch switch is controlled to be turned off, including: in response to the first alternating current signal being in a positive half cycle, and the absolute value of the voltage of the standard sine reference signal being less than the absolute value of the voltage of the high-frequency triangular wave carrier signal, a sine pulse width modulation signal for controlling the first branch switch is generated.

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