High-voltage high-frequency sic mosfet novel power transformer

Abstract

Disclosed in the present invention is a high-voltage high-frequency SiC Mosfet novel power transformer, comprising a superordinate computer, a controller, an inverter circuit, and a signal detection circuit. The superordinate computer is connected to the controller; the inverter circuit uses a three-phase T-type inverter topology circuit to convert high-voltage power in a three-phase circuit into three-phase controllable AC power; the inverter circuit comprises a primary rectifier circuit, a primary DC-AC circuit, a three-phase winding transformer, a secondary rectifier circuit, and a secondary DC-AC circuit; a plurality of SiC Mosfets are used in the primary rectifier circuit, the primary DC-AC circuit, the secondary rectifier circuit, and the secondary DC-AC circuit; the signal detection circuit obtains detection data; and a DSP is provided in the controller, the DSP is provided with an algorithm module, the algorithm module performs an operation on the basis of the detection data to generate a specific instruction, and the controller adjusts the inverter circuit on the basis of operating parameters or the specific instruction. In the present invention, a plurality of SiC Mosfets are used, and the structure of the inverter circuit is optimized, thereby improving the working efficiency; and a detection and control feedback mechanism is additionally provided, so that effective regulation within the transformer can be realized, thereby improving the performance.

Description

A new type of power transformer of high-voltage and high-frequency SiC Mosfet TECHNICAL FIELD

[0001] The present application relates to the technical field of transformers, in particular to a new type of power transformer of high-voltage and high-frequency SiC Mosfet. BACKGROUND

[0002] With the rapid development of power electronics technology, the performance of power transformers, as an important part of the power system, directly affects the quality and conversion efficiency of electric energy. The traditional silicon-based power transformer has problems such as low energy efficiency, serious heat generation, and large size in high-voltage and high-frequency environments due to the limitations of the material itself, making it difficult to meet the needs of modern power systems for high efficiency, compactness, and reliability.

[0003] SiC, which is silicon carbide, is a new type of wide-bandgap semiconductor material with excellent properties such as good high-temperature stability, high breakdown field strength, and high thermal conductivity, making it particularly suitable for the manufacture of high-voltage and high-frequency power electronic devices. Mosfet, which is a metal-oxide-semiconductor field-effect transistor, is a key component in power electronic devices, and its performance directly determines the efficiency and stability of power conversion. Therefore, applying SiC material to Mosfet manufacturing to form SiC Mosfet is an effective way to develop new high-voltage and high-frequency power transformers.

[0004] However, there are at least three problems in the prior art when applying SiC Mosfet to transformers:

[0005] 1) High energy loss, more heat generation, affecting the actual running efficiency;

[0006] 2) The transformer is large in size, not small and lightweight, and has high pressure on installation and maintenance;

[0007] 3) When applying SiC Mosfet to the transformer, it is difficult to adjust the performance or function of the transformer, and there is also a lack of effective detection of the actual circuit of the transformer. SUMMARY

[0008] To solve the above three problems, the present application proposes a new type of power transformer of high-voltage and high-frequency SiC Mosfet, which utilizes multiple SiC Mosfets and optimizes the connection structure to reduce heat generation and improve efficiency. At the same time, the circuit structure in the transformer is optimized, a three-phase T-type inverter topology circuit is adopted, and each circuit is set to a similar structure, making the transformer small in size and easy to maintain. In addition, a signal detection circuit and a controller are also provided to obtain circuit data in a timely and effective manner and make adjustments, further improving the performance of the transformer.

[0009] The following technical solutions are implemented:

[0010] The high-voltage high-frequency SiC Mosfet novel power transformer comprises an upper computer, a controller, an inverter circuit and a signal detection circuit; the upper computer is connected with the controller, and the upper computer is used for setting operation parameters and displaying operation states; the inverter circuit adopts a three-phase T-type inverter topology circuit to convert high-voltage electricity in a three-phase circuit into three-phase controllable alternating current, and the inverter circuit comprises, which are connected in sequence, a primary rectifier circuit, a primary DC-AC circuit, a three-phase winding transformer, a secondary rectifier circuit and a secondary DC-AC circuit, and meanwhile, a plurality of SiC Mosfets are used in the primary rectifier circuit, the primary DC-AC circuit, the secondary rectifier circuit and the secondary DC-AC circuit; wherein the primary rectifier circuit performs primary rectification on high-voltage three-phase electricity input into the transformer to obtain first controllable direct current; the primary DC-AC circuit converts the first controllable direct current into first controllable alternating current; the three-phase winding transformer performs voltage regulation on the first controllable alternating current; the secondary rectifier circuit performs secondary rectification on the first controllable alternating current subjected to voltage regulation to obtain second controllable direct current; the secondary DC-AC circuit converts the second controllable direct current into three-phase controllable alternating current conforming to a power frequency; the signal detection circuit is used for performing real-time detection on a plurality of nodes in the inverter circuit to obtain detection data; the controller is built-in with a DSP, and an algorithm module is set in the DSP; the algorithm module performs operation based on the detection data to generate specific instructions; and the controller adjusts the inverter circuit according to the operation parameters or the specific instructions to regulate the three-phase controllable alternating current into required output.

[0011] A plurality of SiC Mosfets are arranged in the inverter circuit and the connection structure is optimized, so that the heat generation is reduced and the efficiency is improved; meanwhile, the three-phase T-type inverter topology circuit is adopted and each circuit is arranged as a similar structure, so that the transformer can be miniaturized and is convenient to maintain; in addition, the signal detection circuit, the algorithm module and the controller are arranged, so that the circuit data can be obtained in time and effectively and adjusted, and the performance of the transformer is further improved.

[0012] Preferably, the signal detection circuit comprises a current detection circuit; wherein the current detection circuit adopts a current sensor CASR 15-NP to perform current detection on the inverter circuit, an input end of the current sensor CASR 15-NP is connected to a 5V power supply through a first filter circuit, and an output end of the current sensor CASR 15-NP is connected to the controller through a first signal amplifier and a grounding capacitor. The current sensor CASR 15-NP has characteristics of high precision and fast response, and the current detection circuit can obtain current data in time and effectively.

[0013] Preferably, the signal detection circuit further comprises a voltage detection circuit; the voltage detection circuit detects the voltage of the inverter circuit by using a second signal amplifier, the second signal amplifier is powered by a 3.3V power supply through an LC filter circuit, a plurality of matching resistors are arranged at the input end of the second signal amplifier, an RC parallel feedback circuit is arranged between the input end and the output end of the second signal amplifier, and the output end is connected to the controller through a voltage stabilizing resistor and a grounding capacitor. The voltage detection circuit can stably and timely obtain voltage data.

[0014] Preferably, the plurality of SiC Mosfets form a plurality of T-type bridge circuits, and each phase bridge arm of any one of the T-type bridge circuits comprises four SiC Mosfets and anti-parallel diodes. The plurality of T-type bridge circuits have high stability, accuracy and adjustability.

[0015] Preferably, the signal detection circuit further comprises a temperature detection circuit, the temperature detection circuit detects a plurality of nodes in the inverter circuit, performs multi-channel temperature sampling, and transmits the results of the multi-channel temperature sampling to the algorithm module. Temperature detection can effectively obtain the temperature of the circuit and timely detect overheating to ensure the safety of the circuit.

[0016] Preferably, the upper computer is built-in with a man-machine interaction system, and the man-machine interaction system can perform bidirectional transmission with the controller. The man-machine interaction system can better understand the situation in the circuit and perform human intervention.

[0017] Preferably, the DSP is further provided with an EPWM module, an ECAN, an ADC and an EXTI; the EPWM module is used for generating and controlling PWM signals and adjusting the inverter circuit by using the PWM signals; the ECAN is used for supporting bidirectional interaction between the DSP and the upper computer; the ADC is used for receiving detection data, converting the detection data into digital signals and transmitting the digital signals to the algorithm module for processing; and the EXTI is used for controlling the shutdown between the DSP and external signals. The DSP is used for control and processing, and the inverter circuit can be controlled efficiently and accurately.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] The technical scheme of the present application uses a plurality of SiC Mosfets and optimizes the connection structure, thereby reducing the heat generation and improving the efficiency; at the same time, the circuit structure in the transformer is optimized, a three-phase T-type inverter topology circuit is adopted, and each circuit is set to a similar structure, so that the transformer can be miniaturized and is convenient to maintain; in addition, a signal detection circuit, an algorithm module and a controller are arranged, circuit data are obtained timely and effectively, and adjustment is performed, and the performance of the transformer is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 is a structural schematic diagram of a high-voltage high-frequency SiC Mosfet new power transformer;

[0021] Fig. 2 is a circuit structure schematic diagram of the transformer inside a high-voltage high-frequency SiC Mosfet new power transformer;

[0022] Fig. 3 is a framework schematic diagram of controlling the transformer in a high-voltage high-frequency SiC Mosfet new power transformer;

[0023] Fig. 4 is a schematic diagram of a current detection circuit in a high-voltage high-frequency SiC Mosfet new power transformer;

[0024] Fig. 5 is a schematic diagram of a voltage detection circuit in a high-voltage high-frequency SiC Mosfet new power transformer. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings in the embodiments of the present application. EMBODIMENT

[0026] As shown in Fig. 1, it is a structural schematic diagram of a high-voltage high-frequency SiC Mosfet new power transformer, which mainly includes a host computer, a controller, an inverter circuit and a signal detection circuit. The host computer is a computer system, and the operating personnel can set the operating parameters of the transformer on the host computer and make the host computer display the operating state of the inverter circuit. The operating parameters can be parameters related to the set voltage, current, operating time and phase, and the operating state includes normal operation, overvoltage, undervoltage, overcurrent, overheating and open phase, etc. At the same time, the position of the circuit with abnormal state is also displayed. The signal detection circuit is used to detect the three-phase controllable alternating current in the three-phase circuit in real time to obtain detection data.

[0027] In this embodiment, the input end of the inverter circuit receives high-voltage three-phase power, and sequentially performs primary rectification, primary inversion, power transformer transformation, secondary rectification and secondary inversion, so as to obtain output three-phase power meeting the power frequency, and then transmit it to the load requiring power. The power frequency is a frequency requirement, which is the power frequency specified by the actual power consumption area or scene; both rectifications are to convert the power from alternating current to direct current, so as to meet the input requirements of multiple SiC Mosfets and more easily adjust the size of the output voltage; both inversions are to convert the direct current into alternating current.

[0028] As shown in Fig. 2, it is a circuit structure schematic diagram of the transformer inside a high-voltage high-frequency SiC Mosfet new power transformer; as shown in Fig. 3, it is a framework schematic diagram of controlling the transformer in a high-voltage high-frequency SiC Mosfet new power transformer.

[0029] In combination with FIG. 1, FIG. 2 and FIG. 3, the inverter circuit adopts a three-phase T-type inverter topology circuit to convert high-voltage electricity in a three-phase circuit into three-phase controllable alternating current. The inverter circuit adopts a three-phase T-type inverter topology circuit to convert high-voltage electricity in a three-phase circuit into three-phase controllable alternating current. The inverter circuit includes, in sequence, a primary rectifier circuit, a primary DC-AC circuit, a three-phase winding transformer, a secondary rectifier circuit and a secondary DC-AC circuit, and at the same time, a plurality of SiC Mosfets are used in the primary rectifier circuit, the primary DC-AC circuit, the secondary rectifier circuit and the secondary DC-AC circuit. The primary rectifier circuit performs primary rectification on the high-voltage three-phase electricity input to the transformer to obtain first controllable direct current. The primary DC-AC circuit converts the first controllable direct current into first controllable alternating current. The three-phase winding transformer is a power transformer transformer operation, which adjusts the voltage of the first controllable alternating current. The secondary rectifier circuit performs secondary rectification on the first controllable alternating current after voltage adjustment to obtain second controllable direct current; the secondary DC-AC circuit converts the second controllable direct current into second controllable alternating current that meets the power frequency, that is, the final required three-phase controllable alternating current.

[0030] Specifically, the grid three-phase electricity is accessed to the system from the R, Y and B of the input end, and then enters the primary rectifier circuit, and is connected to the capacitors C1, C2 and C3 and the inductors L1, L2 and L3, respectively. The capacitors C1, C2 and C3 are mainly used for filtering and coupling, C1 is an input coupling capacitor, used to isolate the direct current components between the front-stage circuit and the back-stage circuit, C2 is a coupling capacitor between two levels, used to connect two different levels of circuits, and C3 is an alternating current bypass capacitor, used to filter out alternating current interference signals in the circuit. The inductors L1, L2 and L3 are all used for current blocking, filtering and ensuring that the current in the circuit flows as designed, thereby achieving three-phase rectification. Then it enters the primary DC-AC circuit in the inverter circuit, which is also the primary inverter circuit, and the 35 switch tubes Q1-Q35 are all SiC Mosfets, which can efficiently and stably perform voltage conversion. The inductor L1 is connected to the drain of Q1 and Q3 and the source of Q2, and the source of Q3 is connected to the source of Q4; the inductor L2 is connected to the drain of Q5 and Q7 and the source of Q6, and the source of Q7 is connected to the source of Q8; the inductor L3 is connected to the drain of Q9 and Q11 and the source of Q10, and the source of Q3 is connected to the source of Q4; the drains of Q4, Q8 and Q12 are connected to the capacitors C4 and C5.

[0031] High-voltage three-phase electricity passes through the primary rectification output 10KV DC BUS to reach test points A1 and A2, and 10KV DC BUS is a DC bus, that is, a DC power supply bus with a voltage level of 10 kilovolts in a DC power supply system. Then, it reaches test points B1 and B2, and capacitors C6 and C7 are connected in series between B1 and B2. Capacitors C6 and C7 are connected to the drains of Q17, Q21 and Q25, and then connected to the sources of Q18, Q22 and Q26, respectively. The drain of Q18 is connected to the source of Q15, the drain of Q16 and inductor L4, respectively; the source of Q22 is connected to the source of Q19, the drain of Q20 and inductor L5, respectively; and the drain of Q26 is connected to the source of Q23, the drain of Q24 and inductor L6, respectively. Inductors L4, L5 and L6 are connected to capacitors C8, C9 and C10, respectively. Then, it reaches three-phase winding transformer T primary side test points D1, D2 and D3. The primary DC-AC circuit can convert DC to AC, that is, convert DC to AC, through the primary inversion of the three-phase T-type bridge.

[0032] Through the step-up and step-down of three-phase winding transformer T, the output ends U1, V1 and W1 on the secondary side are output, and then enter the secondary rectification circuit to output 800KV DC BUS to reach test points E1 and E2. U1, V1 and W1 are connected to inductors L7, L8 and L9, respectively, and then connected in parallel with capacitors C13, C14 and C15, respectively. Inductor L7 is connected to the drains of Q35 and Q37 and the source of Q36, inductor L8 is connected to the drains of Q31 and Q33 and the source of Q32, and inductor L9 is connected to the drains of Q27 and Q33 and the source of Q28. The sources of Q29, Q33 and Q3 are connected to the corresponding drains of Q30, Q34 and Q38, respectively, and the drains of Q30, Q34 and Q38 are connected to test points E1 and E2. Capacitors C11 and C12 are connected in series between E1 and E2. The above circuit converts the AC voltage again to DC. E1 and E2 test points are connected to test points F1 and F2, respectively.

[0033] Then, into the secondary DC-AC circuit. The series capacitor C13 and C14 between test points F1 and F2, the capacitor C13 and C14 connected to the drain of Q37, Q43 and Q47, and then connected to the source of Q40, Q44 and Q48 respectively. The drain of Q40 is connected to the source of Q37, the drain of Q38 and inductance L7; the source of Q44 is connected to the source of Q41, the drain of Q42 and inductance L8; the drain of Q48 is connected to the source of Q45, the drain of Q46 and inductance L9. Inductance L7, L8 and L9, capacitor C13, C14 and C15 are connected in parallel and respectively connected to the output U2, V2 and W2, which will be converted from the DC input from the test points F1 and F2 to 400V AC 3-phase 50HZ three-phase AC power, AC refers to DC, phase refers to phase. U2, V2 and W2 are output terminals for connecting loads.

[0034] In this embodiment, a large number of SiC Mosfet uses multiple groups of T-type bridge circuit, each group has the same working principle, taking the T-type three-level bridge circuit composed of Q1, Q2, Q3 and Q4 as an example, there are four SiC Mosfet and anti-parallel diodes on each bridge arm, assuming that it works in A phase state, Q1 and Q2 form the main circuit power tube, and Q3 and Q4 form the neutral point power tube. Q1 and Q4 are complementary, Q2 and Q3 are complementary, and Q1 and Q2 cannot be turned on at the same time. The voltage of the two capacitors on the DC side is the same as U dc , the neutral point voltage of the two capacitors is used as a reference, and each bridge arm can output-1 / 2U dc , 0, +1 / 2U dc three levels. Switching state and output level, as shown in Table 1 below. 0 and 1 represent the closing and opening state of the corresponding switch tube, and U d represents the output voltage.

[0035] Table 1:

[0036]

[0037] From the switch state in Table 1, A phase has three switch states; and the three switch states correspond to three-level space, that is, there are 3x3x3=27 working states, a large number of different space vectors are obtained through different states, these space vectors reflect the state of the circuit, and these vectors can be analyzed by using the algorithm module, combined with the relevant data obtained by the current detection circuit and the voltage detection circuit, the current parameters and state of the circuit can be accurately and detailedly determined, and the adjustment scheme can be determined, so as to generate specific instructions to send to the controller, and then adjust the circuit to obtain the power supply required by the test personnel.

[0038] It should be noted that the A phase refers to an output state of an electronic device, and there are B phase and C phase two states, here only A phase is taken as a reference, and B phase or C phase can also be analyzed, and the analysis process is the same.

[0039] The controller of the embodiment adjusts the AD-DC circuit and the DC-AC circuit according to the operating parameters and specific instructions, and adjusts the three-phase controllable alternating current into the required output. The controller uses a DSP chip for control, and a human-computer interaction system is built in the upper computer. The tester can control the DSP chip through the human-computer interaction system, and then timely adjust the DC-AC circuit and the AC-DC circuit.

[0040] As shown in FIG. 4, it is a schematic diagram of a current detection circuit in a new type of high-voltage high-frequency SiC Mosfet power transformer. The current detection circuit can sample the current of multiple test points in the inverter circuit, obtain current information in time, effectively monitor the circuit state, and then find the overcurrent position after analysis and calculation of the algorithm module, and adjust in time to protect the circuit. The 5V power supply is connected to the power supply end U3 of the current sensor CASR 15-NP after passing through the filter circuit composed of L1, C1 and C2, the output end VOUT is connected to the resistor R2, the reference ground end VREF is connected to the resistor R1, and the R2 is connected to the R4 and the signal amplifier. The 3.3V power supply is connected to the signal amplifier after passing through the filter circuit composed of L2, C1 and C2, the output end of the signal amplifier is connected to R3, R5 and C3 for filtering, R5 is connected to C4 and the output terminal, and the output terminal is connected to the controller. The current detection circuit uses the current sensor CASR 15-NP to detect the current of the three-phase controllable alternating current, because the input end of the current sensor CASR 15-NP is connected to the 5V power supply through the first filter circuit, and the output end is connected to the controller through the first signal amplifier and the ground capacitor. The input end of the current detection circuit can adopt multiple parallel branches and set switches for control, so as to test multiple nodes in the inverter circuit, that is, multiple test points, and use switches to obtain corresponding current data respectively, to better monitor the circuit.

[0041] As shown in Figure 5, it is a schematic diagram of a voltage detection circuit in a new type of power transformer of high-voltage high-frequency SiC Mosfet, and the signal detection circuit further comprises a voltage detection circuit. The voltage detection circuit can sample the voltage of multiple nodes in the inverter circuit, obtain the voltage information in time, and then determine whether the detected position is under-voltage or over-voltage after analysis and calculation of the algorithm module, so as to effectively monitor the circuit state. The voltage detection circuit detects the voltage of the three-phase controllable alternating current by using a second signal amplifier. The second signal amplifier is powered by a 3.3V power supply through an LC filter circuit. The input end of the second signal amplifier is provided with a plurality of matching resistors. An RC parallel feedback circuit is arranged between the input end and the output end of the second signal amplifier. At the same time, the output end is connected to the controller after passing through a voltage stabilizing resistor and a grounding capacitor. Specifically, the voltage to be measured is between Ph_A and NUE. Ph_A is connected to the signal amplifier after passing through R1-R4. NUE is connected to R10 and the signal amplifier after passing through R5-R8. The 3.3V power supply is connected to the signal amplifier after passing through the filter circuit composed of L2, C1 and C2. The output end of the signal amplifier is connected to R9, R11 and C3 for filtering. R11 is connected to C4 and the output terminal. The output end is connected to the controller. The input end of the voltage detection circuit can also adopt a plurality of parallel branches and be controlled by a switch, so as to test a plurality of nodes in the inverter circuit.

[0042] In this embodiment, the signal detection circuit can also be provided with a temperature detection circuit. The temperature detection circuit detects a plurality of test points in the inverter circuit to perform multi-channel temperature sampling, so as to obtain the current temperature of the circuit, and then determine whether the state of each part of the circuit is overheated after analysis and calculation of the algorithm module. If the temperature of part of the test points is too high, it means that there may be a power transmission safety problem, which needs to be stopped in time or quickly remind the tester to repair.

[0043] In addition, the signal detection circuit can also be provided with a phase detection circuit. The phase detection circuit detects a plurality of test points in the inverter circuit to perform multi-channel phase sampling, so as to determine whether the phase of each part of the circuit exists a phase problem. In addition, phase=frequency x time. Detecting the phase is equivalent to detecting the frequency, so as to know whether the inverter circuit meets the requirement of power frequency.

[0044] In this embodiment, the DSP can adopt a TMS320F28379 digital signal processor, which is internally provided with an EPWM module, an ECAN, an ADC, an EXTI and an algorithm module, is responsible for analyzing and calculating the data provided by the signal detection circuit, determining whether the circuits corresponding to each node of the detection exist problems such as under-voltage, over-voltage, over-current, over-heat and phase loss, and repairing the problems. The EPWM module is an electronic pulse width modulation module, which is used to generate and control PWM signals, and can transmit the PWM signals to the circuit with problems through the interface of the control card, adjust the corresponding SiC Mosfet, so as to repair the circuit problem and make it meet the actual demand. The ECAN is an interface for realizing the interaction between the controller and the upper computer, can interact with the man-machine interaction system in the upper computer, transmit the data of each node of the inverter circuit, the circuit with problems and the actual adjustment operation to be performed to the tester, and at the same time, the man-machine interaction system also allows the tester to actively input the content of the inverter circuit adjustment and send it to the ECAN and then transmit the PWM signal to the EPWM module for actual adjustment. The ADC is an analog-to-digital converter, which converts the analog signal transmitted by the signal detection circuit into a digital signal and then sends it to the algorithm module. The algorithm module first pre-processes the received digital signal, that is, filters, scales and calibrates it to ensure accuracy, and then integrates the data, especially when multiple digital signals are received, which may represent voltage-related data, current-related data, phase-related data and temperature-related data, etc. The multiple digital signals are integrated to form a comprehensive state view of the inverter circuit. Since the electronic devices used in actual use all have threshold values related to specification parameters, the algorithm module compares the threshold-related data and confirms the state of the detection node of the signal detection circuit by using the wavelet analysis method, finally determines the node and circuit with problems, and then generates specific instructions to solve these problems and sends them to the EPWM module for processing. The EXTI is an external interrupt and event controller, which is used to control whether the DSP interrupts the external signal and determine which circuit problems are indicated by the digital signal converted by the ADC.

[0045] In summary, the present application utilizes multiple SiC Mosfets and optimizes the connection structure, thereby reducing the heat generation and improving the efficiency; at the same time, the circuit structure in the transformer is optimized, a three-phase T-type inverter topology circuit is adopted and each circuit is set to a similar structure, so that the transformer can be miniaturized and is also convenient to maintain; in addition, the signal detection circuit, the algorithm module and the controller are also set to obtain the circuit data in time and effectively and adjust them, which further improves the performance of the transformer and has significant progressiveness.

[0046] The above examples only illustrate the technical idea of the present application, and cannot be used to limit the protection scope of the present application. Any modification made according to the technical idea of the present application on the basis of the technical scheme falls within the protection scope of the present application.

Claims

1. A new type of power transformer for high voltage high frequency SiC Mosfet, characterized by, The application relates to a high-voltage inverter system. The upper computer is connected with the controller, and the upper computer is used for setting operation parameters and displaying operation states; the inverter circuit adopts a three-phase T-type inverter topology circuit to convert high-voltage electricity in a three-phase circuit into three-phase controllable alternating current, and the inverter circuit comprises, which are connected in sequence, a primary rectification circuit, a primary DC-AC circuit, a three-phase winding transformer, a secondary rectification circuit and a secondary DC-AC circuit, and a plurality of SiC Mosfets are used in the primary rectification circuit, the primary DC-AC circuit, the secondary rectification circuit and the secondary DC-AC circuit; wherein the primary rectification circuit performs primary rectification on high-voltage three-phase electricity input into the transformer to obtain first controllable direct current; the primary DC-AC circuit converts the first controllable direct current into first controllable alternating current; the three-phase winding transformer performs voltage regulation on the first controllable alternating current; the secondary rectification circuit performs secondary rectification on the first controllable alternating current subjected to voltage regulation to obtain second controllable direct current; and the secondary DC-AC circuit converts the second controllable direct current into three-phase controllable alternating current conforming to a power frequency. The signal detection circuit is used for detecting a plurality of nodes in the inverter circuit in real time to obtain detection data; the controller is internally provided with a DSP, an algorithm module is arranged in the DSP, the algorithm module performs operation based on the detection data to generate specific instructions, and the controller adjusts the inverter circuit according to the operation parameters or the specific instructions to adjust the three-phase controllable alternating current into required output.

2. A new type of power transformer of high-voltage high-frequency SiC Mosfet according to claim 1, characterized in that, The signal detection circuit comprises a current detection circuit. The current detection circuit adopts a current sensor CASR 15-NP to detect the current of the inverter circuit, the input end of the current sensor CASR 15-NP is connected to a 5V power supply through a first filter circuit, and the output end is connected to the controller through a first signal amplifier and a grounding capacitor.

3. A new type of power transformer of high-voltage high-frequency SiC Mosfet according to claim 1, characterized in that, The signal detection circuit further comprises a voltage detection circuit; the voltage detection circuit detects the voltage of the inverter circuit by using a second signal amplifier, the second signal amplifier is powered by a 3.3V power supply through an LC filter circuit, a plurality of matching resistors are arranged at the input end of the second signal amplifier, an RC parallel feedback circuit is arranged between the input end and the output end of the second signal amplifier, and the output end is connected to the controller after passing through a voltage stabilizing resistor and a grounding capacitor.

4. A new type of power transformer of high-voltage high-frequency SiC Mosfet according to claim 1, characterized by, The plurality of SiC Mosfets form a plurality of T-type bridge circuits, and each phase bridge arm of any one of the T-type bridge circuits comprises four SiC Mosfets and anti-parallel diodes.

5. A new type of power transformer of high voltage and high frequency SiC Mosfet according to claim 1 characterized by, The signal detection circuit further comprises a temperature detection circuit, the temperature detection circuit detects a plurality of nodes in the inverter circuit to perform multi-channel temperature sampling, and transmits the results of the multi-channel temperature sampling to the algorithm module.

6. A new type of power transformer of high voltage and high frequency SiC Mosfet according to claim 1 characterized by, The upper computer is internally provided with a man-machine interaction system, and the man-machine interaction system can perform bidirectional transmission with the controller.

7. A new type of power transformer of high voltage and high frequency SiC Mosfet according to claim 1 characterized by, The DSP is further provided with an EPWM module, an ECAN, an ADC and an EXTI; the EPWM module is used for generating and controlling a PWM signal, and the PWM signal is used for adjusting an inverter circuit; the ECAN is used for supporting bidirectional interaction between the DSP and an upper computer; the ADC is used for receiving detection data, converting the detection data into a digital signal and transmitting the digital signal to an algorithm module for processing; and the EXTI is used for controlling the DSP and an external signal to be turned off.

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