Three-phase full-voltage AA type safety power supply

Abstract

The invention discloses a three-phase full-voltage AA type safety power supply, which comprises an input voltage selection unit, a relay allocation unit, a central control processing module, an output power supply detection unit and a three-phase double-H-bridge transformation reduction circuit, the central control processing module is electrically connected with the input voltage selection unit, the relay allocation unit, the output power supply detection unit and the three-phase double-H-bridge transformation reduction circuit respectively; each phase of double-H-bridge transformation reduction circuit comprises a front-stage common-source silicon carbide H bridge, a transformer, a rear-stage common-source silicon carbide H bridge and a phase-shift driving synchronous reduction group, the input end of the front-stage common-source silicon carbide H bridge is electrically connected with the relay deploying unit, and the output end of the front-stage common-source silicon carbide H bridge is electrically connected with the transformer and the phase-shift driving synchronous reduction group respectively; the transformer is electrically connected with the post-stage common-source silicon carbide H-bridge, and the post-stage common-source silicon carbide H-bridge is further electrically connected with the output power supply detection unit and the post-stage common-source silicon carbide H-bridge. According to the invention, the effects of reducing the size, reducing the loss and saving the cost can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of smart grid safety power supplies, and in particular to a three-phase full-voltage AA type safety power supply. Background Art

[0002] When traditional IT systems, smart grids, and other power supply systems need to be isolated, most of them use three-phase power frequency isolation transformers and three-phase isolation inverters. Since the power frequency voltage is low and cannot be high-frequency, the isolation transformer is very large, heavy, expensive, and inefficient. These are all defects of the power frequency transformer. When using a three-phase isolation inverter, although the volume is reduced, the three-phase isolation inverter must go through a complex process of rectification, filtering, PFC boost, LLC modulation, and then rectification, filtering, and inversion to obtain isolated three-phase power. In addition, the circuit structure of the three-phase isolation inverter is very complex, resulting in high cost and many failure points. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a three-phase full-voltage AA type safety power supply.

[0004] The object of the present invention is achieved through the following technical solutions: A three-phase full-voltage AA-type safety power supply, comprising: an input voltage selection unit, a relay allocation unit, a central control processing module, an output power detection unit, and a three-phase double H-bridge transformer reduction circuit, wherein the central control processing module is electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit, and the three-phase double H-bridge transformer reduction circuit respectively; The input voltage selection unit is used to connect to the power supply and input the voltage source signal into the central control processing module. The central control processing module controls the on / off of the relay allocation unit according to the voltage source signal. The output end of the relay allocation unit is electrically connected to the three-phase double H-bridge transformer-reduction circuit. The output end of the three-phase double H-bridge transformer-reduction circuit outputs a voltage signal via the output power detection unit. The dual H-bridge transformer-reduction circuit of each phase includes a front-stage common-source silicon carbide H-bridge, a transformer, a rear-stage common-source silicon carbide H-bridge and a phase-shift driven synchronous reduction group. The input end of the front-stage common-source silicon carbide H-bridge is electrically connected to the relay allocation unit, the output end of the front-stage common-source silicon carbide H-bridge is electrically connected to the primary of the transformer and the input end of the phase-shift driven synchronous reduction group, the secondary of the transformer is electrically connected to the rear-stage common-source silicon carbide H-bridge, and the output end of the rear-stage common-source silicon carbide H-bridge is electrically connected to the output power detection unit and the rear-stage common-source silicon carbide H-bridge, respectively.

[0005] In one embodiment, a circuit breaker is provided between the input end of the input voltage selection unit and the input power supply.

[0006] In one embodiment, in the three-phase double H-bridge transformer reduction circuit, the phase lead angle between every two transformers is 120 degrees.

[0007] In one embodiment, the input voltage selection unit includes a synchronous signal sampling circuit and a synchronous square wave locking circuit, the input end of the synchronous signal sampling circuit is used to access the synchronous power supply signal, the output end of the synchronous signal sampling circuit is electrically connected to the synchronous square wave locking circuit, and the synchronous square wave locking circuit is electrically connected to the relay allocation unit and the phase shift drive synchronous restoration group respectively.

[0008] In one embodiment, the phase-shift drive synchronous restoration group includes a phase-shift drive synchronization circuit, a secondary side restoration drive circuit, a front-stage drive circuit and a rear-stage drive circuit, the input end of the phase-shift drive synchronization circuit is electrically connected to the output end of the synchronous square wave locking circuit, the output end of the phase-shift drive synchronization circuit is electrically connected to the secondary side restoration drive circuit and the front-stage drive circuit respectively, and the front-stage drive circuit is used to drive the front-stage common-source silicon carbide H-bridge to work; The input end of the secondary side reduction drive circuit is also electrically connected to the transformer, the output end of the subsequent drive circuit is electrically connected to the subsequent drive circuit, and the subsequent drive circuit is used to drive the subsequent common source silicon carbide H-bridge to operate.

[0009] In one embodiment, the central control processing module includes a CPU processor, a differential acquisition circuit and a DC acquisition circuit. The CPU processor is electrically connected to the differential acquisition circuit and the DC acquisition circuit respectively, and the CPU processor is also electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit and the three-phase dual H-bridge transformer reduction circuit respectively.

[0010] In one embodiment, the central control processing module further includes a phase shift control circuit, which is electrically connected to the CPU processor, and the output end of the phase shift control circuit is also electrically connected to the input end of the phase shift drive synchronous reduction group.

[0011] In one embodiment, the front-stage common-source silicon carbide H-bridge includes eight silicon carbide switching tubes, where every two of the silicon carbide switching tubes are connected in series to form a control tube group of the H-bridge, and four of the control tube groups are further connected in series to form an H-bridge; The series connection node of two of the control tube groups is electrically connected to one primary input end of the transformer, and the series connection node of the other two of the control tube groups is electrically connected to the other primary input end of the transformer.

[0012] In one embodiment, the rear-stage common-source silicon carbide H-bridge includes four independently controlled dual silicon carbide MOS tube groups, and the four dual silicon carbide MOS tube groups are sequentially connected in series; The series connection nodes of two of the dual silicon carbide MOS tube groups are electrically connected to one secondary output end of the transformer, and the series connection nodes of the other two dual silicon carbide MOS tube groups are electrically connected to the other secondary output end of the transformer.

[0013] The advantages and beneficial effects of the present invention compared to the prior art are as follows: The present invention provides a three-phase full-voltage AA-type safety power supply. By providing a front-stage common-source silicon carbide H-bridge, a transformer, a rear-stage common-source silicon carbide H-bridge, and a phase-shift drive synchronous reduction group, the present invention utilizes a common-source silicon carbide MOS transistor to form a bidirectional electronic switch. Power directly enters the MOS transistor without requiring complex circuits such as rectification, filtering, and PFC. High-frequency phase-shift drive synchronization is employed to directly modulate various voltages, such as alternating current, square wave power, and triangular wave power. A high-frequency transformer generates a four-quadrant power supply, which is then restored and output by a synchronous reduction circuit. This overcomes the drawback of the isolation transformer, which can only input sinusoidal AC power. The power supply achieves an efficiency exceeding 95%, far exceeding the efficiency of three-phase power frequency transformers and three-phase isolation inverters. In a sense, the power supply can achieve 1:1 isolation and reduction of various voltage sources, overcoming the drawback of the transformer's single function, reducing size, lowering losses, and saving costs. The power supply can be widely used in the fields of new energy, smart grids, and safe electricity use, particularly as a power supply requiring isolation in scientific research laboratories and hospitals. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a functional block diagram of a three-phase full-voltage AA-type safety power supply according to one embodiment of the present invention; Figure 2 for Figure 1 The circuit diagram of the input voltage selection unit shown; Figure 3 for Figure 1 The circuit diagram of the phase-shift drive synchronization circuit shown in (1); Figure 4 for Figure 1 The circuit diagram of the phase-shift drive synchronization circuit shown in FIG. Figure 5 for Figure 1 The circuit diagram of the secondary side restoration drive circuit shown; Figure 6 for Figure 1 The circuit diagram of the front-stage driving circuit shown; Figure 7 for Figure 1 The circuit diagram of the phase shift control circuit shown; Figure 8 for Figure 1 The circuit diagram of the differential acquisition circuit shown; Figure 9 for Figure 1 The circuit diagram of the DC acquisition circuit shown; Figure 10 for Figure 1 The circuit diagram of the front-stage common-source silicon carbide H-bridge, transformer and rear-stage common-source silicon carbide H-bridge is shown; Figure 11 for Figure 1 The waveform diagram of the phase-shift drive shown; Figure 12 This is a circuit diagram of the present invention when the three-phase AC input B is 120 degrees ahead, C is 120 degrees behind, and A is 0 degrees; Figure 13 for Figure 1 The waveform diagram of the three-phase AC four-quadrant output power supply shown; Figure 14 for Figure 1 The waveform diagram of the three-phase AC composite power supply shown; Figure 15 for Figure 1 The waveform diagram of the triangular wave and square wave AC composite power supply shown; Figure 16 for Figure 1 The waveform diagrams of short-circuit arc extinguishing and fault arc extinguishing shown in the figure are as follows: Figure 17 for Figure 1 The functional block diagram of the three-phase full voltage AA type safety power supply is shown. DETAILED DESCRIPTION

[0015] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0016] This is a three-phase full-voltage AA-type safety power supply that uses 12 groups of silicon carbide (SIC) MOS tubes in a common-source manner to form a bidirectional electronic switch, and is composed of a high-frequency phase-shift modulation and synchronous restoration method. It fundamentally changes the need for large transformers and complex three-phase inverters when isolating three-phase power, and at the same time solves the problem of being unable to isolate three-phase square waves and triangular waves.

[0017] Traditional transformers require output voltage changes only through taps. The three-phase full-voltage AA-type safety power supply, however, simply changes the phase shift angle. Its efficiency exceeds 95%, far exceeding that of three-phase power frequency transformers and three-phase isolation inverters. In a sense, it can isolate and restore various voltage sources 1:1, overcoming the single-function limitations of transformers, reducing size, losses, and costs. This device is widely used in new energy, smart grid, and power safety applications, particularly as an isolated power source in research laboratories and hospitals. The output restoration stage of the three-phase full-voltage AA-type safety power supply also utilizes 12 sets of bidirectional electronic switches. These 12 bidirectional switches form a high-speed electronic circuit breaker, capable of shutting off in microseconds (µs) between neutral and phase lines, and between phase lines, in the event of a load or equipment short-circuit. The low-pass filtering creates an LC channel that dissipates residual current, eliminating sparks in the event of a load or line short-circuit, thereby improving electrical fire safety.

[0018] The three-phase, full-voltage, AA-type safety power supply can be used in various power supply applications requiring three-phase electrical isolation. It can provide AC-AC, DC-DC, square-wave-square-wave, triangle-wave-triangle, and any other voltage source waveform requiring isolation. It utilizes DSP or MCU phase-shifting for closed-loop voltage regulation, enabling stable output voltage even in environments with large voltage fluctuations. It also incorporates a waveform correction function, controlling the phase shift angle to adjust the output power waveform in real time if the voltage waveform is non-standard. It can fundamentally replace isolated power-frequency transformers, achieving higher frequencies. The output LC filter channel filters out interference from grid harmonics that could affect equipment.

[0019] The three-phase, full-voltage, AA-type safety power supply utilizes a high-frequency three-phase power frequency transformer, replacing the direct power frequency transformer conversion method. This fundamentally addresses the bulk, weight, and low efficiency of three-phase power frequency transformers, transforming low-voltage IT power distribution systems. In the new energy sector, it can isolate and restore DC power, while also providing step-up and step-down functions, achieving isolation and voltage stability in industrial and commercial energy storage power supplies. However, in safety power supply applications, the large number of windings and the large effective area of ​​copper wire in power frequency transformers result in significant distributed capacitance, leading to significant residual currents that pose a threat to human life. The high-frequency operation of the three-phase, full-voltage, AA-type safety power supply, reaching frequencies ranging from tens to hundreds of kHz, minimizes transformer copper usage, reduces distributed capacitance, and therefore minimizes residual currents. In the civilian sector, it can be used as a power supply for home distribution systems, in military applications as a safety power supply to ensure network security, and in the commercial sector, it can be used in shopping malls, shops, office buildings, residential buildings, hospitals, schools, government agencies, banks, and fire protection systems. In industrial applications, it can be used in power distribution systems such as mining, metallurgy, factories, and smart grids.

[0020] This specialized power supply integrates a three-phase power frequency transformer, a universal voltage source, AC / DC input capabilities, voltage regulation, and isolation. It addresses the complex structure, large size, and high cost of three-phase power frequency transformers through high-frequency phase-shifted synchronous restoration, resolving fundamental issues of volume, weight, and efficiency. The use of AA conversion technology eliminates numerous steps involved in the three-phase power frequency inverter, including rectification, filtering, PFC, and boost / inversion, reducing components and points of failure. The power supply directly enters an H-bridge bidirectional electronic switch for phase-shift modulation. The high-frequency transformer splits the input voltage into three four-quadrant voltages with phases staggered by 120 degrees. A synchronous restoration circuit then restores the voltage to the same value as the input voltage.

[0021] Specifically, see Figures 1-17 A three-phase full-voltage AA-type safety power supply includes: an input voltage selection unit, a relay allocation unit, a central control processing module, an output power detection unit, and a three-phase dual H-bridge transformer-reduction circuit. The central control processing module is electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit, and the three-phase dual H-bridge transformer-reduction circuit respectively. In this embodiment, a circuit breaker is provided between the input end of the input voltage selection unit and the input power supply.

[0022] The input voltage selection unit is used to connect to the power supply and input the voltage source signal into the central control processing module. The central control processing module controls the on / off of the relay allocation unit according to the voltage source signal. The output end of the relay allocation unit is electrically connected to the three-phase double H-bridge transformer-reduction circuit. The output end of the three-phase double H-bridge transformer-reduction circuit outputs a voltage signal via the output power detection unit. The dual H-bridge transformer-reduction circuit of each phase includes a front-stage common-source silicon carbide H-bridge, a transformer, a rear-stage common-source silicon carbide H-bridge and a phase-shift driven synchronous reduction group. The input end of the front-stage common-source silicon carbide H-bridge is electrically connected to the relay allocation unit, the output end of the front-stage common-source silicon carbide H-bridge is electrically connected to the primary of the transformer and the input end of the phase-shift driven synchronous reduction group, the secondary of the transformer is electrically connected to the rear-stage common-source silicon carbide H-bridge, and the output end of the rear-stage common-source silicon carbide H-bridge is electrically connected to the output power detection unit and the rear-stage common-source silicon carbide H-bridge, respectively.

[0023] It should be noted that the voltage source enters the input voltage selection unit through the circuit breaker Q1 and sends the obtained input voltage source signal to the CPU. After detecting the voltage source, the CPU controls the relay allocation unit to send the voltage to the three groups of H-bridges A / B / C. Group A phase-shift drive and synchronous restoration group is responsible for the AB voltage source, group B phase-shift drive and synchronous restoration group is responsible for the BC voltage source, and group C phase-shift drive and synchronous restoration group is responsible for the CA voltage source.

[0024] The driving signal of the post-stage synchronous restoration group comes from the transformer. When not working or stopping working, the three groups of H-bridge switches K9-K12, K21-K24, and K33-K36 of the A / B / C post-stages are always in the on state to discharge the residual current output by the post-stages.

[0025] Preferably, in the three-phase double H-bridge transformer reduction circuit, the phase lead angle between every two transformers is 120 degrees.

[0026] See also Figure 2 The input voltage selection unit includes a synchronous signal sampling circuit and a synchronous square wave locking circuit. The input end of the synchronous signal sampling circuit is used to access the synchronous power supply signal. The output end of the synchronous signal sampling circuit is electrically connected to the synchronous square wave locking circuit. The synchronous square wave locking circuit is electrically connected to the relay allocation unit and the phase-shift drive synchronous restoration group respectively.

[0027] Specifically, input terminal J1 is the synchronous signal sampling input. The A / B / C signals are fed to voltage-divider resistors R12 / R12 / R18 / R21, R35 / R36 / R42 / R43, and R58 / R59 / R66 / R67, respectively, to separate the +VA / +VB / +VC signals. These signals are then fed to comparators U3, U6, and U9, generating six drive signal groups that are then fed into the synchronous square-wave lock circuit. This circuit then outputs synchronized square-wave drive signals (+APWM / -APWM / +BPWM / -BPWM / +CPWM / -CPWM) with 120-degree phase shifts. When any two input groups from terminals J1-A / B / C receive DC voltages, only the corresponding input group operates, while the other group deactivates. At this point, the positive and negative comparison voltages corresponding to comparators U3, U6, and U9 are separated and transferred to the corresponding comparators. When the input terminal J1-A / B / C collects the AC input signal U3 / U6 / U9, the AC upper half cycle and the negative half cycle are stripped to generate a synchronization signal. When any one group of synchronous square waves is locked and working, the other group is prohibited from working.

[0028] See also Figure 2 The phase-shift drive synchronous restoration group includes a phase-shift drive synchronization circuit, a secondary side restoration drive circuit, a front-stage drive circuit and a rear-stage drive circuit. The input end of the phase-shift drive synchronization circuit is electrically connected to the output end of the synchronous square wave locking circuit. The output end of the phase-shift drive synchronization circuit is electrically connected to the secondary side restoration drive circuit and the front-stage drive circuit respectively. The front-stage drive circuit is used to drive the front-stage common-source silicon carbide H-bridge to work; The input end of the secondary side reduction drive circuit is also electrically connected to the transformer, the output end of the subsequent drive circuit is electrically connected to the subsequent drive circuit, and the subsequent drive circuit is used to drive the subsequent common source silicon carbide H-bridge to operate.

[0029] The phase-shift drive synchronization circuit consists of gate drivers U1 / U2. For example, when the A / B phase voltages are positive and B negative, the synchronous square wave passes directly through diodes D1 / D3 / D5 / D7 and resistors R1 / R3 / R5 / R7, sending it directly to the pre-stage drive circuits of Q2 / Q4 / Q6 / Q8 to drive MOS transistors K3 / K4 / K7 / K8. Since pins 1 / 5 / 8 / 12 of the gate circuits are high, the phase-shifted signal enters the gate drivers via pins 2 / 6 / 9 / 13 of the gate circuits, is amplified by the push-pull circuit, and then sent directly to the pre-stage drive circuits of Q1 / Q3 / Q5 / Q7 to drive MOS transistors K1 / K2 / K5 / K6. When the A / B phase voltages B are positive and A is negative, the above process is reversed. The driving methods of groups B and C are the same as those of group A.

[0030] See also Figure 3 The secondary-side restoration drive circuit includes a transformer drive winding, an inverter U3, and a push-pull circuit. When the three-phase full-voltage AA safety power supply is stopped and inverter U3 is in operation, A+ / B+ transmit drive signals through H9 / H10 / H11 / H12 to the subsequent drive circuit, which then drives the secondary-side restoration MOS transistors to shut down accordingly. When A+ is positive, MOS groups K9 / K12 are turned off, and when B+ is positive, MOS groups K10 / K11 are turned off. At this point, the four-quadrant power supply is restored to a two-quadrant power supply and fed to an LC low-pass filter. The output power detection unit includes an LC low-pass filter.

[0031] See also Figure 4 The subsequent driver circuits are powered by an isolated push-pull power supply. The 15V voltage is generated by a switching power supply and then passes through a push-pull transformer to generate four power supplies. These four power supplies provide the main voltages VCC1 / VCC2 for the buck circuits. Chip U28 steps down VCC1 to a +20V drive voltage, and chip U30 generates a -5V drive voltage from VCC2, which powers the forward and backward driver circuits and driver chip U17, respectively. Since the other groups are similar to Group A, they are only described once.

[0032] See also Figure 5 The central control processing module includes a CPU processor, a differential acquisition circuit and a DC acquisition circuit. The CPU processor is electrically connected to the differential acquisition circuit and the DC acquisition circuit respectively, and the CPU processor is also electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit and the three-phase dual H-bridge transformer reduction circuit respectively.

[0033] It should be noted that the differential acquisition circuit uses integrated chip U10 to collect AC voltage and current. After the AC current enters the voltage divider resistors through J19 / J21 / J22, it generates IAP / IAN / IBP / IPN / ICP / ICN and enters the acquisition chip. The AC voltage then passes through voltage acquisition transformer T5 / T6 / T7, through the voltage divider resistors, and enters the acquisition chip. The acquisition chip communicates with the CPU via SPI. The input voltage and current circuits are identical. The DC acquisition circuit, namely the DC voltage and current acquisition circuit, uses an isolated power supply. Transformer T8 generates an isolated voltage of 5V-1, which powers chip U13. DC voltage input can only be input from channels A / C and B / C; input from channels A / B is invalid. After voltage division by resistors R57 / R63 / R71 / R77 / R82 / R87 / R92, the DC voltage enters the ADC acquisition chip U12. U13 is an I2C isolated communication chip connected to the CPU.

[0034] The CPU uses the STM32 series. Since the phase shifting is handled by hardware, the CPU's processing is simplified. Pins 1, 2, and 3 of the CPU handle relay operations, while SPI processes data from the RN83 chip. I2C communication handles data from the memory and DC power input. External communications utilize RS485 and RS232.

[0035] See also Figure 6 The central control processing module also includes a phase-shift control circuit, which is electrically connected to the CPU processor. The output of the phase-shift control circuit is also electrically connected to the input of the phase-shift drive synchronization reduction group. It should be noted that the phase-shift control circuit is composed of a phase-shift control chip U1. The adjustable potentiometer R2 is for manual voltage adjustment. When automatic voltage adjustment is enabled, the adjustable resistor R2 is removed. DISB is the enable signal. Pins 13 / 14 / 17 / 18 of chip U1 are the phase-shift drive output pins, which send the drive signal to the gate driver for processing.

[0036] Furthermore, the front-stage common-source silicon carbide H-bridge includes eight silicon carbide switching tubes, where every two of the silicon carbide switching tubes are connected in series to form a control tube group of the H-bridge, and four of the control tube groups are further connected in series to form an H-bridge; wherein the series connection nodes of two of the control tube groups are electrically connected to one primary input terminal of the transformer, and the series connection nodes of the other two control tube groups are electrically connected to the other primary input terminal of the transformer.

[0037] It should also be noted that the rear-stage common-source SiC H-bridge includes four independently controlled dual SiC MOS tube groups, which are connected in series in sequence; the series connection nodes of two of the dual SiC MOS tube groups are electrically connected to one secondary output terminal of the transformer, and the series connection nodes of the other two dual SiC MOS tube groups are electrically connected to the other secondary output terminal of the transformer.

[0038] During operation, when phase A receives AC input and its starting point coincides with the zero-crossing point, MOSs K3 / K4 / K7 / K8 enter the positive half-cycle direct-through state with a synchronized square wave. To reduce switching losses, MOSs K1 / K2 / K5 / K6 perform phase-shifted SPWM modulation. When MOSs K2 / K5 are enabled for transmission, MOS groups K9 / K12 are disabled, and transformer secondary energy is transferred by MOS groups K10 / K11. When energy is transferred to MOSs K1 / K6, MOS groups K10 / K11 are disabled, and energy is transferred by MOS groups K9 / K12. The operating ranges of phases B and C are similar to those of phase A and are not repeated here. When phase A receives the negative half-cycle of AC input, the above operating mode is reversed. The same applies to the DC input.

[0039] When a short circuit occurs between any phase or line of the A / B / C output terminals, or when a load short circuit occurs, all power switches on the secondary side are turned on, while all switches on the primary side are turned off. This action is completed within 200 nanoseconds. When the secondary switches are closed, they consume all the remaining current in the line. If a fault arc occurs on the secondary side, the frequency of oscillations within the time period will differ from the actual output current frequency. The CPU will then collect the current and compare it with the primary current. If the oscillation frequency is greater than the CPU comparison frequency, it is considered a fault arc; if it is less than the CPU comparison frequency, it is considered normal, and the spark generated by the short circuit is suppressed.

[0040] The three-phase full-voltage AA-type safety power supply of the present invention is applicable to various power supply types, such as DC, sinusoidal AC, square wave, pulse, triangle wave voltage, step wave voltage, etc., and is suitable for various power supply systems such as IT systems, smart grids, etc.

[0041] The present invention changes the fundamental problems of weight, volume and price of traditional three-phase industrial frequency transformers, changing from industrial frequency to high frequency; the present invention changes the traditional three-phase industrial frequency transformer to change the voltage into a step mode to achieve linear voltage regulation without wave; the present invention changes the function of traditional transformers that cannot achieve conversion due to triangular wave and square wave voltage harmonics; the present invention changes the function of traditional transformers that cannot achieve DC isolation transformers; the present invention improves the efficiency of traditional transformers; the present invention adds an arc extinguishing function when the transformer output is short-circuited or fails; the present invention realizes the ability of the transformer to have unlimited input and unlimited output.

[0042] The above-described embodiments merely represent several embodiments of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A three-phase full voltage AA type safety power supply, characterized in that: include: An input voltage selection unit, a relay allocation unit, a central control processing module, an output power detection unit, and a three-phase double H-bridge transformer reduction circuit, wherein the central control processing module is electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit, and the three-phase double H-bridge transformer reduction circuit respectively; The input voltage selection unit is used to connect to the power supply and input the voltage source signal into the central control processing module. The central control processing module controls the on / off of the relay allocation unit according to the voltage source signal. The output end of the relay allocation unit is electrically connected to the three-phase double H-bridge transformer-reduction circuit. The output end of the three-phase double H-bridge transformer-reduction circuit outputs a voltage signal via the output power detection unit. The dual H-bridge transformer-reduction circuit of each phase includes a front-stage common-source silicon carbide H-bridge, a transformer, a rear-stage common-source silicon carbide H-bridge and a phase-shift driven synchronous reduction group. The input end of the front-stage common-source silicon carbide H-bridge is electrically connected to the relay allocation unit, the output end of the front-stage common-source silicon carbide H-bridge is electrically connected to the primary of the transformer and the input end of the phase-shift driven synchronous reduction group, the secondary of the transformer is electrically connected to the rear-stage common-source silicon carbide H-bridge, and the output end of the rear-stage common-source silicon carbide H-bridge is electrically connected to the output power detection unit and the rear-stage common-source silicon carbide H-bridge, respectively.

2. The three-phase full-voltage AA type safety power supply according to claim 1, characterized in that: A circuit breaker is provided between the input end of the input voltage selection unit and the input power supply.

3. The three-phase full-voltage AA type safety power supply according to claim 2, characterized in that: In the three-phase double H-bridge transformer reduction circuit, the phase lead angle between every two transformers is 120 degrees.

4. The three-phase full-voltage AA type safety power supply according to claim 1, characterized in that: The input voltage selection unit includes a synchronous signal sampling circuit and a synchronous square wave locking circuit. The input end of the synchronous signal sampling circuit is used to access the synchronous power supply signal. The output end of the synchronous signal sampling circuit is electrically connected to the synchronous square wave locking circuit. The synchronous square wave locking circuit is electrically connected to the relay allocation unit and the phase shift drive synchronous restoration group respectively.

5. The three-phase full-voltage AA type safety power supply according to claim 4, characterized in that: The phase-shift drive synchronous restoration group includes a phase-shift drive synchronization circuit, a secondary side restoration drive circuit, a front-stage drive circuit and a rear-stage drive circuit. The input end of the phase-shift drive synchronization circuit is electrically connected to the output end of the synchronous square wave locking circuit. The output end of the phase-shift drive synchronization circuit is electrically connected to the secondary side restoration drive circuit and the front-stage drive circuit respectively. The front-stage drive circuit is used to drive the front-stage common-source silicon carbide H-bridge to work; The input end of the secondary side reduction drive circuit is also electrically connected to the transformer, the output end of the subsequent drive circuit is electrically connected to the subsequent drive circuit, and the subsequent drive circuit is used to drive the subsequent common source silicon carbide H-bridge to operate.

6. The three-phase full voltage AA type safety power supply according to claim 1, characterized in that: The central control processing module includes a CPU processor, a differential acquisition circuit and a DC acquisition circuit. The CPU processor is electrically connected to the differential acquisition circuit and the DC acquisition circuit respectively, and the CPU processor is also electrically connected to the input voltage selection unit, the relay allocation unit, the output power detection unit and the three-phase dual H-bridge transformer reduction circuit respectively.

7. The three-phase full-voltage AA type safety power supply according to claim 6, characterized in that: The central control processing module further includes a phase shift control circuit, which is electrically connected to the CPU processor. The output end of the phase shift control circuit is also electrically connected to the input end of the phase shift drive synchronous restoration group.

8. The three-phase full-voltage AA type safety power supply according to claim 1, characterized in that: The front-stage common-source silicon carbide H-bridge includes eight silicon carbide switching tubes, where every two of the silicon carbide switching tubes are connected in series to form a control tube group of the H-bridge, and four of the control tube groups are further connected in series to form an H-bridge; The series connection node of two of the control tube groups is electrically connected to one primary input end of the transformer, and the series connection node of the other two of the control tube groups is electrically connected to the other primary input end of the transformer.

9. The three-phase full-voltage AA type safety power supply according to claim 1, characterized in that: The rear-stage common-source silicon carbide H-bridge includes four independently controlled dual silicon carbide MOS tube groups, and the four dual silicon carbide MOS tube groups are sequentially connected in series; The series connection nodes of two of the dual silicon carbide MOS tube groups are electrically connected to one secondary output end of the transformer, and the series connection nodes of the other two dual silicon carbide MOS tube groups are electrically connected to the other secondary output end of the transformer.

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