Equivalent measuring method and device for power consumption of high-voltage pulse circuit

Abstract

This invention discloses an equivalent measurement method and apparatus for power consumption in high-voltage pulse circuits. The method calibrates the thermal parameters of the insulating liquid system using a constant-power heating source, transforming circuit losses, which are difficult to measure directly, into precise temperature changes, thereby accurately calibrating static losses. Based on this, by recording stable temperature rises under dynamic operating conditions and combining thermal parameters, the equivalent total power consumption is inferred. Furthermore, through experiments with multiple sets of parameters, the distribution patterns of conduction and switching losses are analyzed, constructing a power consumption prediction model that balances accuracy and practicality. This method eliminates the need for direct sampling on the high-voltage side, effectively avoiding electromagnetic interference, significantly reducing equipment costs and implementation difficulty, and improving the accuracy and repeatability of power consumption assessment. Through equivalent measurement and calculation, this method can determine the power consumption under actual operating conditions and separate static, switching, and conduction losses to obtain experimental formulas for predicting power consumption under all operating conditions, providing effective support for the thermal design and reliability optimization of high-voltage pulse circuits.

Description

Technical Field

[0001] This invention belongs to the field of power electronics measurement technology, and relates to an equivalent measurement method and device for the power consumption of a high-voltage pulse circuit. Background Technology

[0002] With the rapid development of power electronics technology, solid-state switching devices, represented by Insulated Gate Bipolar Transistors (IGBTs) and Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs), have become core components for constructing high-voltage pulse circuits due to their advantages of high efficiency, fast response, and ease of control. However, accurately evaluating the power consumption of switching modules remains a major technical challenge in the research and development and experimentation of these high-voltage, high-power circuits. Currently, the industry generally relies on theoretical formulas to calculate power consumption based on the parameters and operating conditions provided in the device datasheets. While this method is simple, the calculated results often have significant errors compared to actual power consumption. The main reason for this is that the test conditions in the datasheets are limited and cannot fully cover the parameter performance of devices under complex actual operating conditions. Furthermore, when multiple devices are connected in series and parallel, due to individual differences and circuit layout, the actual operating parameters of each device are difficult to be completely consistent, leading to distortion of the calculation results based on uniform nominal parameters. More importantly, the electromagnetic interference, temperature gradient, parasitic parameters, and other factors in the actual working environment are far more complex than the test environment in the manual. These factors, which are not taken into account, greatly affect the accuracy of power consumption.

[0003] On the other hand, the technical parameters of high-voltage pulse circuits are extremely high, making direct experimental measurement and verification exceptionally difficult and costly. For example, for a 15kV / 50A high-voltage switching module based on IGBT series connection, the experimental conditions for real-world power consumption testing and evaluation are extremely stringent: a DC power supply capable of outputting 15kV / 50A with a power capacity of up to 750kW is required, along with a resistive load capable of withstanding the same voltage and current surges. These extreme experimental conditions not only place extremely high technical demands on the equipment but also result in extremely high costs for building and maintaining the test system, significantly limiting R&D progress and cost control. Therefore, whether from the perspective of improving computational accuracy or reducing experimental costs, the industry urgently needs a new technological approach—namely, developing a method and device that has lower requirements for experimental conditions while accurately evaluating the power consumption and technical performance of high-performance IGBT and MOSFET switching modules—to overcome existing technological bottlenecks and promote the further development of high-voltage pulse technology. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides an equivalent measurement method and apparatus for the power consumption of high-voltage pulse circuits, thereby solving the technical problems of large errors, high costs and difficulties in implementation of existing high-voltage pulse circuit power consumption assessment.

[0005] This invention is achieved through the following technical solution: An equivalent measurement method for power consumption in a high-voltage pulse circuit includes the following steps: S1: Obtain the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static loss of the high-voltage pulse circuit under test in the insulating liquid system. S2: Based on the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static losses of the high-voltage pulse circuit under test, and in conjunction with the pre-built power consumption prediction model, determine the total power consumption of the high-voltage pulse circuit under test. The power consumption prediction model is constructed as follows: S21: A natural cooling experiment is conducted on the insulating liquid system using a constant power heating source to determine the thermal parameters of the insulating liquid system. Then, the high-voltage pulse circuit to be tested is placed in the insulating liquid system, and static operating conditions are applied to the high-voltage pulse circuit to be tested. Based on the temperature rise of the insulating liquid system and the thermal parameters, the static loss of the high-voltage pulse circuit to be tested is determined. S22: Run the high-voltage pulse circuit under test under a preset dynamic operating condition until the insulating liquid system reaches a stable temperature rise, record its total temperature change, and determine the equivalent total power consumption of the high-voltage pulse circuit under test based on the thermal parameters. S23: Based on the equivalent total power consumption and static loss, change the operating parameters of the high-voltage pulse circuit under test to conduct multiple power consumption tests, analyze the influence of different parameters on conduction loss and switching loss, and establish the power consumption prediction model.

[0006] Preferably, the operating condition parameters include switching frequency, conduction current, and duty cycle; the hardware configuration parameters include the number of series devices; and the device characteristic parameters include threshold voltage, dynamic on-resistance, thermal loss factor, and switching energy coefficient.

[0007] Preferably, the thermal parameters include the overall heat dissipation coefficient and the pure heat capacity.

[0008] Preferably, the comprehensive heat dissipation coefficient is obtained by: heating the insulating liquid system to a stable temperature using a constant power heat source and then turning it off; recording the temperature-time data of the insulating liquid system during the natural cooling process from the stable temperature to the initial reference temperature to obtain a natural cooling curve; and performing exponential fitting on the natural cooling curve to obtain the comprehensive heat dissipation coefficient.

[0009] Preferably, the pure heat capacity is obtained by: heating the insulating liquid system with a constant power heating source, recording the temperature-time data during the process of rising from the initial reference temperature to a stable temperature, and obtaining a temperature rise curve; and using the temperature rise curve data and the comprehensive heat dissipation coefficient to obtain the pure heat capacity.

[0010] Preferably, before step S21, the method further includes: allowing the insulating liquid system to stand until its temperature is fully balanced with room temperature, and recording this balanced temperature as the initial reference temperature.

[0011] Preferably, step S23 specifically includes: First, a baseline power consumption test is conducted under short pulse width conditions. Then, while keeping other operating parameters unchanged, a single operating parameter is changed to conduct a power consumption test. The impact of this parameter on the total loss is analyzed, and its calculation factor in the power consumption prediction model is determined. Finally, when the changes of multiple parameters can be combined into a single comprehensive parameter, this comprehensive parameter is used to construct the power consumption prediction model.

[0012] Preferably, after step S23, the method further includes: using the power consumption prediction model to predict the power consumption under preset dynamic operating conditions, comparing the prediction results with the actual measurement results, evaluating the accuracy of the power consumption prediction model based on the error, and if the accuracy does not meet the preset conditions, returning to step S23 to add test conditions and continue to optimize the power consumption prediction model.

[0013] Preferably, the preset condition is that the relative error between the predicted result and the actual measurement result is less than 10%.

[0014] An equivalent measurement device for the power consumption of a high-voltage pulse circuit includes a pulse parameter measurement module, a constant power heating source module, a load circuit module, an insulating liquid module, and a temperature measurement system module; the temperature sensing unit of the temperature measurement system module is placed in the insulating liquid of the insulating liquid module. During measurement, the constant power heating source module and the high voltage pulse circuit module under test are independently immersed in the insulating liquid module; and the pulse parameter measurement module and the load circuit module are connected to the high voltage pulse circuit module under test.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses an equivalent measurement method for the power consumption of a high-voltage pulse circuit. It employs a constant-power heat source to calibrate the system's thermal parameters. Through natural cooling and temperature rise experiments, circuit losses, which are difficult to measure directly, are transformed into accurately measurable temperature changes, thus achieving accurate calibration of static losses. Based on this, by recording stable temperature rises under dynamic operating conditions and combining thermal parameters, the equivalent total power consumption is inferred. Furthermore, through multi-set parameter experiments, the distribution patterns of conduction and switching losses are analyzed, constructing a power consumption prediction model that balances accuracy and practicality. This method eliminates the need for direct sampling on the high-voltage side, reducing equipment costs and implementation difficulty. It also avoids the influence of electromagnetic interference on the measurement results, significantly improving the accuracy and repeatability of power consumption assessment, and providing effective support for the thermal design and reliability optimization of high-voltage pulse circuits. This method, through equivalent power consumption measurement and calculation, can determine the power consumption of a high-voltage pulse circuit under actual operating conditions. By changing the test conditions, it can separate the static losses, switching losses, and conduction losses of solid-state switches, obtaining experimental formulas for predicting the power consumption of the high-voltage pulse circuit under all operating conditions. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the equivalent measurement device for power consumption of a high-voltage pulse circuit according to the present invention. Figure 2 A schematic diagram of a high-voltage switching circuit for connecting the load to the low-level terminal; Figure 3 A schematic diagram of a high-voltage switching circuit for connecting a load to a high-level terminal; Figure 4 This is a schematic diagram of a high-voltage half-bridge circuit; Figure 5 This is a schematic diagram of a high-voltage full-bridge circuit; Figure 6 This is a flowchart of an equivalent measurement method for the power consumption of a high-voltage pulse circuit according to the present invention.

[0018] The system comprises: 1. Pulse parameter measurement module; 2. High-voltage pulse circuit module under test; 3. Constant power heating source module; 4. Load circuit module; 5. Insulating liquid module; 6. Temperature measurement system module; 11. First drive circuit; 12. First switch module; 21. Second drive circuit; 22. Second switch module; 31. Third drive circuit; 32. Half-bridge circuit module; 41. Fourth drive circuit; 42. Full-bridge circuit module. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0024] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0025] The present invention will now be described in further detail with reference to the accompanying drawings: Example 1 like Figure 1 As shown, this invention discloses an equivalent measurement device for the power consumption of a high-voltage pulse circuit. The measurement device includes a pulse parameter measurement module 1, a constant power heating source module 3, a load circuit module 4, an insulating liquid module 5, and a temperature measurement system module 6; the temperature sensing unit of the temperature measurement system module 6 is placed in the insulating liquid of the insulating liquid module 5. During measurement, the constant power heating source module 3 and the high voltage pulse circuit module 2 under test are independently immersed in the insulating liquid module 5; and the pulse parameter measurement module 1 and the load circuit module 4 are connected to the high voltage pulse circuit module 2 under test; specifically, the output terminal of the high voltage pulse circuit module 2 under test is connected to the input terminal of the load circuit module 4, and the high voltage pulse circuit module 2 under test generates a high voltage pulse to drive the load circuit module 4 to work. The pulse parameter measurement module 1 mainly includes an oscilloscope, a high-voltage probe, and a current probe. It is primarily used to measure the voltage amplitude, rise and fall time, pulse width, pulse overshoot, pulse frequency, and pulse duty cycle of the high-voltage pulse output by the high-voltage pulse circuit module 2 under test; as well as the amplitude, rise and fall time, and overshoot of the pulse current. The pulse parameter measurement module 1 is connected to the high-voltage pulse circuit module 2 under test and is used to measure the various technical parameters of the high-voltage pulse output by the high-voltage pulse circuit module 2 under test.

[0026] The high-voltage pulse circuit module 2 under test includes three types: high-voltage switching circuit, high-voltage half-bridge circuit, and high-voltage full-bridge circuit. All three types can generate different forms of high-voltage pulses to drive the load circuit module 4.

[0027] in, Figure 2 A schematic diagram of a high-voltage switching circuit for connecting the load to the low-level terminal; Figure 3 This is a schematic diagram of a high-voltage switching circuit with the load connected to a high-level terminal; the high-voltage switching circuit with the load connected to a low-level terminal includes a first driving circuit 11 and a first switching module 12; the high-voltage switching circuit with the load connected to a high-level terminal includes a second driving circuit 21 and a second switching module 22.

[0028] The first driving circuit 11 and the second driving circuit 21 are respectively used to generate driving signals for multiple switches in the first switching module 12 and the second switching module 22. Specifically, the first driving circuit 11 and the second driving circuit 21 are driven by switch S. n (n=1,2,3…) are connected in series and connected to a high voltage V P Used to achieve high voltage pulses, S nIt can be a single solid-state switch device or a switching module composed of multiple solid-state switches connected in series and parallel, generating a drive signal V. kn (n=1,2,3…); The load connected to the first switch module 12 and the second switch module 22 is the load circuit module 4. The load circuit module 4 can be resistive, capacitive, inductive, or any combination of these three load types, and can be connected to the low-level terminal of a high-voltage circuit (e.g., Figure 2 (as shown) or high level terminal ( Figure 3 (As shown). The drive circuit generates a drive signal with the same frequency and pulse width as the expected high-voltage pulse to synchronously drive the series switch. The series switch outputs the high-voltage pulse by rapidly switching on and off. The high-voltage pulse is then output to the load circuit to complete the energy transfer of the high-voltage pulse.

[0029] Figure 4 This is a schematic diagram of a high-voltage half-bridge circuit, which includes a third drive circuit 31 and a half-bridge circuit module 32. The third drive circuit 31 is used to generate drive signals V for switches S1 and S2 in the half-bridge circuit module 32. k1 V k2 The half-bridge circuit module 32 consists of switches S1 and S2 connected in series, and is connected to the high voltage V. P The half-bridge circuit module 32 is used to generate high-voltage pulses. S1 and S2 can be single solid-state switching devices or switching modules composed of multiple solid-state switches connected in series and parallel. The load connected to the half-bridge circuit module 32 is the load circuit module 4, which can be resistive, capacitive, inductive, or any combination of these three load types. The third driving circuit 31 generates a driving signal with the same frequency and pulse width as the expected high-voltage pulse to drive the half-bridge circuit module 32 to work. The half-bridge circuit module 32 achieves the output of high-voltage pulses through rapid switching on and off. The high-voltage pulse is output to the load circuit module 4 to complete the energy transfer of the high-voltage pulse.

[0030] Figure 5 This is a schematic diagram of a high-voltage full-bridge circuit, which includes a fourth drive circuit 41 and a full-bridge circuit module 42. The fourth drive circuit 41 is used to generate drive signals V for switches S1, S2, S3, and S4 in the full-bridge circuit module 42. k1 V k2 V k3 V k4 The full-bridge circuit module 42 consists of switches S1, S2, S3, and S4 connected in series and parallel, and is connected to a high voltage V. PUsed to generate high-voltage pulses, S1, S2, S3, and S4 can be single solid-state switching devices or switching modules composed of multiple solid-state switches connected in series and parallel. The load connected to the full-bridge circuit module 42 is the load circuit module 4, which can be resistive, capacitive, inductive, or any combination of these three load types. The fourth drive circuit 41 generates a drive signal with the same frequency and pulse width as the expected high-voltage pulse to drive the full-bridge circuit module 42 to work. The full-bridge circuit module 42 achieves the output of high-voltage pulses through the rapid switching on and off of the switches. The high-voltage pulse is output to the load circuit module 4 to complete the energy transfer of the high-voltage pulse.

[0031] The constant power heating source module 3 consists of a heating circuit with constant power. Its input power can be AC ​​or DC, and regardless of the type of input power, its output power should remain constant. After the constant power heating source module 3 operates at its rated voltage for a period of time t1, its heat output can be calculated by multiplying its rated power P1 by the heating time t1, i.e., heat output Q = P1 × t1. In use, the constant power heating source module 3 is placed in the insulating liquid module 5 to provide a known constant thermal power during the calibration phase. The constant power heating source module 3, placed in the insulating liquid module 5, is a heating circuit with constant power, providing accurate heat output for the equivalent measurement of the power consumption of the high-voltage pulse circuit module 2 under test.

[0032] Load circuit module 4 is the connected load of the high-voltage pulse circuit module 2 under test. Only after connecting load circuit module 4 can the power consumption of the high-voltage pulse circuit module 2 under the condition of load circuit module 4 be evaluated. Load circuit module 4 can be resistive, capacitive, inductive, or any combination of two of these three types, or a combination of these three load types.

[0033] The insulating liquid module 5 is mainly used to compare the power consumption of the high voltage pulse circuit module 2 under test and the constant power heating source module 3 during operation, thereby inferring the power consumption of the high voltage pulse circuit module 2 under certain operating conditions, obtaining the power consumption calculation method of the high voltage pulse circuit module 2 under a wider range of operating conditions, and realizing the accurate power consumption under more complex and higher operating conditions with limited experimental conditions.

[0034] The temperature measurement system module 6 is used to measure the temperature change of the insulating liquid module 5. For example, under rated power P1, the constant power heating source module 3 causes the temperature of the insulating liquid module 5 to rise from T1 to T2 after time t1, and the heat generated is Q = P1 × t1. If the high-voltage pulse circuit module 2 under test operates under the conditions of the load circuit module 4 for time t2, and also causes the temperature of the insulating liquid module 5 to rise from T1 to T2, then it can be assumed that the heat generated by the high-voltage pulse circuit module 2 under test is also Q. In this case, it can be assumed that the power of the high-voltage pulse circuit module 2 under test is P2, and P2 × t2 = P1 × t1. Generally, the time difference between t1 and t2 should be kept as small as possible, such as less than 600 seconds.

[0035] Example 2 This invention discloses an equivalent measurement method for the power consumption of a high-voltage pulse circuit, comprising the following steps: S1: Obtain the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static loss of the high-voltage pulse circuit under test in the insulating liquid system. The operating condition parameters include switching frequency, conduction current, and duty cycle; the hardware configuration parameters include the number of series devices; and the device characteristic parameters include threshold voltage, dynamic on-resistance, thermal loss factor, and switching energy coefficient. S2: Based on the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static losses of the high-voltage pulse circuit under test, and in conjunction with the pre-built power consumption prediction model, determine the total power consumption of the high-voltage pulse circuit under test.

[0036] The static loss is obtained as follows: A natural cooling experiment was conducted on an insulating liquid system using a constant power heat source with known power to determine the thermal parameters of the insulating liquid system, including the comprehensive heat dissipation coefficient and the pure heat capacity. Then, the high-voltage pulse circuit under test is placed in an insulating liquid system, and static operating conditions are applied to the high-voltage pulse circuit under test. Based on the temperature rise of the insulating liquid system and the thermal parameters, the static loss of the high-voltage pulse circuit under test is determined. The power consumption prediction model is constructed as follows: S21, Thermal parameter calibration and static loss measurement: A natural cooling experiment is conducted on the insulating liquid system using a constant power heating source to determine the thermal parameters of the insulating liquid system, including the comprehensive heat dissipation coefficient and pure heat capacity; then the high-voltage pulse circuit under test is placed in the insulating liquid system, and static operating conditions are applied to the high-voltage pulse circuit under test. Based on the temperature rise of the insulating liquid system and the thermal parameters, the static loss of the high-voltage pulse circuit under test is determined. S22, Total power consumption equivalent measurement: The high voltage pulse circuit under test is run under a preset dynamic operating condition until the insulating liquid system reaches a stable temperature rise, the total temperature change is recorded, and the total power consumption of the high voltage pulse circuit under test is determined based on the thermal parameters. This process is called total power consumption equivalent measurement. S23, Loss separation and fitting formula establishment: Based on the total power consumption and static loss, change the operating parameters of the high-voltage pulse circuit under test to conduct multiple power consumption tests, analyze the influence of different parameters on conduction loss and switching loss, and establish the power consumption prediction model, i.e., the fitting formula used to calculate the total power consumption; the operating parameters are single operating parameters or comprehensive operating parameters. S24, Fitting Formula Verification and Optimization: Use the power consumption prediction model to predict the power consumption under preset dynamic operating conditions, and compare the prediction results with the actual measurement results. Evaluate the accuracy of the power consumption prediction model based on the error. If the accuracy does not meet the preset conditions, return to step S23 to add test conditions to optimize the power consumption prediction model.

[0037] Preferably, the error between the predicted result and the actual measurement result is less than 10%.

[0038] The acquisition of the power consumption of the high-voltage pulse circuit under test includes: measuring the constant power heat source and conducting natural cooling experiments to determine the pure heat capacity and comprehensive heat dissipation coefficient of the insulating liquid, and on this basis, measuring the static loss; conducting equivalent power consumption tests to determine the total power consumption of the high-voltage pulse circuit; conducting equivalent tests on the technical indicators of the switching module to determine the fitting formulas for conduction loss and switching loss; using the fitting formulas to predict the power consumption of the high-voltage pulse circuit in the equivalent test and verifying the accuracy of the fitting formulas; and using the fitting formulas to predict the power consumption of the high-voltage pulse circuit under any operating condition.

[0039] Specifically, such as Figure 6 As shown, the above-mentioned equivalent measurement method for the power consumption of a high-voltage pulse circuit includes the following steps: Step 1: Measurement and natural cooling experiment of constant power heating source to determine the thermal parameters of insulating liquid and static loss of high voltage pulse circuit.

[0040] Before conducting the equivalent power consumption test, considering the influence of environmental factors such as room temperature and heat dissipation coefficient on the heat generation test, it is necessary to determine the thermal parameters of the insulating liquid through constant power heat source measurement and natural cooling experiment. Before the experiment begins, the insulating liquid is allowed to stand for a sufficient time (e.g., 1-2 hours) to allow its temperature to fully equilibrate with room temperature, and this equilibrium temperature is recorded. T 0 is used as the initial reference. After initial equilibration, the system is briefly heated using a constant-power heat source of known power to raise the temperature of the insulating liquid to a stable value. T stable ,Turn off the heat source and begin recording the temperature change of the insulating liquid over time until the temperature drops sufficiently and approaches its normal value. T 0, ultimately yielding multiple natural cooling curves. According to Newton's law of cooling, the heat dissipation power of the insulating liquid during the cooling stage is directly proportional to the temperature difference. Therefore, by performing an exponential fit on the cooling curve data, the comprehensive heat dissipation coefficient of the insulating liquid can be accurately calculated. K .

[0041] Next, the system is heated using a constant power heating source of known power, and after a certain time... Δt Afterwards, the system is at its initial temperature. T 0 rises to T stable Record the system temperature-time curve during the heating process, and then allow the system to cool naturally to room temperature. Repeat the above process and record multiple heating curves. According to the law of conservation of energy, at any moment during heating, part of the input power is used to increase the internal energy of the system, which manifests as a temperature increase, and part is dissipated through heat dissipation. Using the recorded multiple sets of heating curve data, combined with the known comprehensive heat dissipation coefficient... K By curve fitting, the pure heat capacity of the system can be derived. C sys .

[0042] After completing the above calibration and obtaining the accurate thermal parameters of the system under the current experimental environment, static loss testing can be performed on the high-voltage pulse circuit under test. Remove the heat source, apply the specified static operating conditions to the high-voltage pulse circuit module under test, and record the system temperature difference. ΔT At this point, based on the calibrated thermal parameters, the static loss can be calculated directly and accurately using the following formula.

[0043]

[0044] in, P static For static losses, C sys For the pure heat capacity of the system, K To consider the overall heat dissipation coefficient, The rate of temperature change refers to the speed at which the temperature of the test system changes over time during the heating process. For system temperature difference; Step 2: Perform an equivalent power consumption test to determine the total power consumption of the high-voltage pulse circuit.

[0045] Set the operating conditions required for the high-voltage pulse circuit, such as setting the frequency. f =100Hz, pulse width t on =50μs, current amplitude through the load I C=50A, connect the power supply, and run the circuit under the above conditions for a sufficient period of time until the oil bath system, i.e., insulating liquid module 5, reaches a significant and stable temperature rise. Record the temperature of the oil bath system throughout the entire working period and for a period of time after its completion. From the temperature curve, extract the total temperature change from the start-up time to the time when the temperature reaches a stable plateau after its shutdown, and record it as . ΔT sw This value represents the increase in system temperature caused by the total heat energy released by the switch under test conditions. This temperature-time curve data should be fully saved as a control group for subsequent comparisons.

[0046] According to the principle of energy conservation, in an oil bath system with consistent heat dissipation conditions, the amount of heat required to cause the same temperature increase is the same. The total power consumption is calculated using the temperature rise curve of the constant power heating source from step 1 and the calibrated thermal parameters. P total The reverse derivation is the same as the static loss formula in step 1.

[0047] Step 3: Equivalent test of the technical specifications of the switching module to determine the fitting formula for conduction loss and switching loss.

[0048] The operating losses of a solid-state switch are as follows:

[0049] in, For static losses, For conduction loss, For switching losses, This refers to the reverse recovery loss of the diode. For leakage current loss, this method can separate and accurately calculate the three types of losses: static loss, switching loss and conduction loss.

[0050] Static loss As determined in step 1, based on the requirement to separate switching losses and conduction losses, power loss measurements under various operating conditions are necessary. First, power consumption tests are conducted under short pulse width conditions. This test result is used as a baseline. While keeping other operating parameters unchanged, a single independent operating parameter (such as frequency or current) is changed, and the power consumption test results under this single independent parameter change are recorded. Power consumption tests are then conducted for multiple operating parameters with independent parameter changes, and the test results are recorded. The test results are analyzed. Under the condition of a single independent operating parameter change, the impact of the changed parameter on conduction and switching losses is analyzed to determine the position of the changed parameter in the formula fitting the total loss. For example, it is generally believed that conduction loss is usually proportional to the square of the current, and switching loss is usually proportional to the frequency. Therefore, by analyzing the trend of total loss changes when different parameters change, it can be determined where the parameter should be placed in the formula. If, during the test, the total loss doubles when the frequency doubles, it indicates that this part of the loss is mainly switching loss; if the loss quadruples when the current doubles, it indicates that it is mainly conduction loss. When multiple parameters have the same effect, the influence of the combined operating parameters should be considered. For example, changes in frequency and pulse width may be combined into changes in duty cycle. After completing the test and verification of the combined operating parameters, the combined operating parameters can be directly used to fit the formula.

[0051] Step 4: Use the fitting formula to predict the power consumption of the high-voltage pulse circuit module in the equivalent test, and verify the accuracy of the fitting formula.

[0052] Based on the fitting formula, predictions are made for the working conditions tested in step 3. The prediction results are compared with the actual test results, and the relative error is calculated. The accuracy of the fitting formula is evaluated based on the error. When the accuracy does not meet the evaluation criteria (e.g., the relative error exceeds 10%), the process returns to step 3, additional test conditions are added, and the test results are analyzed again to obtain a more accurate fitting formula.

[0053] Step 5: Use the fitting formula to predict the power consumption of the high-voltage pulse circuit module under any operating condition.

[0054] By substituting the operating parameters (such as frequency, pulse width, voltage, current, etc.) of a high-voltage pulse circuit under any operating condition into the fitting formula, the calculation result of the fitting formula is the power consumption prediction result under that operating condition. In this way, the power consumption of a high-voltage pulse circuit under complex operating conditions can be obtained under limited experimental conditions.

[0055] This method can be used to measure the power consumption of three types of high-voltage pulse circuits: high-voltage switching circuits, high-voltage half-bridge circuits, and high-voltage full-bridge circuits. A schematic diagram of a high-voltage switching circuit is shown below. Figure 2 As shown, the power consumption measurement object is the first switching module 12; the schematic diagram of the high-voltage half-bridge circuit is shown below. Figure 4As shown, the power consumption measurement object is the half-bridge circuit module 32; the schematic diagram of the high-voltage full-bridge circuit is shown below. Figure 5 As shown, the power consumption measurement object is the full-bridge circuit module 42. The switch S in the above circuit... n (n=1,2,3…) can be a single solid-state switch or a switch module composed of multiple solid-state switches connected in series and parallel.

[0056] The core of this method lies in summarizing the power consumption test results of high-voltage pulse circuits under various operating conditions. Through data analysis, static losses, switching losses, and conduction losses are separated from the overall losses, achieving high-precision prediction of these losses under all operating conditions. When the current testing environment cannot meet the experimental requirements of high-power high-voltage pulse circuits, equivalent power consumption tests and equivalent tests of switching module technical indicators are conducted under existing experimental conditions to summarize fitting formulas for conduction and switching losses, achieving high-precision prediction of high-power high-voltage pulse circuit losses. This invention obtains power consumption test results for changes in a single independent operating parameter by changing the independent operating parameters of the high-voltage pulse circuit, including operating frequency, pulse width, current, and voltage. Under the condition of a single variable, data analysis is performed on the changes in conduction and switching losses to obtain fitting formulas for each operating parameter and switching and conduction losses. For comprehensive operating parameters simultaneously affected by multiple independent operating parameters, such as charge and duty cycle, the independent operating parameters are changed while the comprehensive operating parameters remain unchanged. Analysis is then used to determine the position of the comprehensive operating parameters in the fitting formulas. This invention, when separating the switching losses of a high-voltage pulse circuit, introduces a correction factor to adjust the fitting formula for the switching losses based on the inherent characteristics of the solid-state switches constituting the circuit. This balances the effects of tail current, junction temperature rise at high frequencies, parasitic capacitance, and on-resistance. The correction factor introduced in this method is not independent but is collaboratively adjusted by multiple independent operating parameters of the high-voltage pulse circuit. Furthermore, before separating the switching and conduction losses of the high-voltage pulse circuit, the static losses of the high-voltage pulse circuit are determined through constant power heat source calibration and natural cooling experiments. Equivalent power consumption testing is then used to achieve high-precision measurement of the heat loss of the high-voltage pulse circuit without the need for an electrical probe.

[0057] In summary, due to the large errors in calculating the power consumption of pulse circuits based on the datasheets of solid-state switches such as IGBTs and MOSFETs, and the high cost and stringent testing conditions of experimental measurements, this invention proposes an equivalent measurement method and device for the power consumption of high-voltage pulse circuits. Through equivalent power consumption measurement, accurate estimation of the power consumption of high-voltage pulse circuits can be achieved. This method, through equivalent testing of the technical specifications of the switching module, combined with the inherent operating characteristics of the solid-state switch to introduce correction factors, determines the fitting formula for conduction loss and switching loss, achieving accurate prediction of conduction loss and switching loss. Ultimately, it can obtain accurate power consumption of high-voltage pulse circuits under complex operating conditions under limited experimental conditions. In other words, this method, through equivalent power consumption measurement and calculation, can determine the power consumption of high-voltage pulse circuits under actual operating conditions; by changing the test conditions, it can separate the static loss, switching loss, and conduction loss of the solid-state switch, obtaining experimental formulas for predicting the power consumption of high-voltage pulse circuits under all operating conditions.

[0058] Example 3 High-voltage IGBTs (HV-IGBTs) face extremely high voltage stress and complex switching transients in pulsed power applications. This is due to the significant tail current and on-state voltage drop of HV-IGBTs. V CE For positive temperature coefficient characteristics, traditional linear estimation methods based on datasheets often introduce huge errors.

[0059] like Figure 2 As shown, this embodiment takes a high-voltage pulse circuit with IGBTs in series as an example to measure its power consumption, that is, the measurement object is the series switch module 21. In this embodiment, the switch S in the series switch module 21 n (n=1,2,3…) can be a single solid-state switch or a switch module composed of multiple solid-state switches connected in series and parallel. All tests below are conducted at S… n The test was conducted using a single IGBT, and the specific testing process is as follows: Step 1: Measurement and natural cooling experiment of constant power heating source to determine the thermal parameters of insulating liquid and static loss of high voltage pulse circuit.

[0060] In the experiment, the insulating liquid system was an insulating oil bath calorimetric system, equipped with a stirring rod to improve the uneven temperature distribution within the oil bath system. The heat balance equation is as follows: (1) in, It is the operating power of a constant power heating source. It is the pure heat capacity of the system. It is the temperature of the oil bath system. It is the ambient temperature. To consider the overall heat dissipation coefficient, This represents the rate of temperature change.

[0061] This experiment recorded the temperature rise curves and natural cooling curves of multiple constant power heating sources, and obtained the comprehensive heat dissipation coefficient of the insulating liquid through curve fitting. With pure heat capacity .

[0062] Obtain the precise thermal parameters (overall heat dissipation coefficient) of the insulating fluid. With pure heat capacity After that, the static loss test can be performed on the high-voltage pulse circuit under test. Remove the constant power heating source, place the high-voltage pulse circuit under test in the oil bath system, and operate the high-voltage pulse circuit under static conditions of 3kV and 0Hz. After the system temperature reaches a new thermal steady state, record the steady-state temperature difference. ΔT At this point, the static power consumption of the circuit and the heat dissipation of the system reach equilibrium. Based on the calibrated thermal parameters, the static loss of the high-voltage pulse circuit is obtained. This static loss is the total heat loss of the circuit under static operating conditions, which includes, but is not limited to, the voltage equalization resistor loss and the high-voltage leakage current loss.

[0063] Step 2: Perform an equivalent power consumption test to determine the total power consumption of the high-voltage pulse circuit.

[0064] After obtaining the thermal parameters of the insulating liquid, the total power consumption of the high-voltage pulse circuit will be measured. The specific measurement method is as follows: First, the high-voltage pulse circuit under test is placed in an oil bath system and operated for a period of time under the conditions of 100Hz frequency, 50μs pulse width, and 50A current. The temperature change of the oil bath system during this period is recorded, and this temperature rise curve is retained as a control group. The pure heat capacity and the overall heat dissipation coefficient of the system are known. By analyzing the data of the control group curve and the temperature rise curve of the constant power heat source, the total power consumption can be derived in reverse.

[0065] Step 3: Equivalent test of the technical indicators of the switching module to determine the fitting formula between conduction loss and switching loss, which is the power consumption prediction model in this invention.

[0066] In this embodiment, the reverse recovery loss of the diode in the switching module is extremely small and negligible. Based on the requirement to separate switching losses from conduction losses, power tests were conducted on the series IGBT switching module under various operating conditions, including pulse width variation, frequency variation, current variation, and high-frequency operation tests. Through these four sets of tests, conduction losses and switching losses were successfully separated, and a nonlinear fitting formula for the total loss and operating parameters was obtained, as follows: (2) in, Total power consumption For static losses, For switching frequency, For switching energy coefficient, To conduct current, This is the switching current loss index. It is the heat-induced loss factor. The number of devices connected in series. Duty cycle, This is the IGBT threshold voltage. This is the dynamic on-resistance.

[0067] In the fitting formula, a switching current loss index is introduced to address the tail current present in IGBT solid-state switches. Corrections were made; to address the junction temperature rise issue during high-frequency operation, a thermal loss correction factor was introduced. The proposed nonlinear fitting formula is corrected. In this embodiment, the average prediction error is controlled within 10% under a wide operating range of 10A-50A, 100Hz-1kHz, and 50μs-500μs. The fitting formula obtained in this embodiment has high accuracy.

[0068] Using the fitting formula in this embodiment, the predicted power consumption of the high-voltage pulse circuit can be obtained by substituting the operating parameters under any operating condition into the fitting formula. In this embodiment, for the power consumption prediction of the high-voltage pulse circuit under any operating condition, the static loss... The switching energy coefficient has been determined in step 1. Switching current loss index With heat-induced loss factor The switching frequency has been determined in step 3. , conduction current Number of series devices Duty cycle 、 IGBT threshold voltage With dynamic on-resistance If the switching frequency is an inherent parameter under specific operating conditions, then... , conduction current Number of series devices Duty cycle 、 IGBT threshold voltage With dynamic on-resistance Substitute the values ​​directly into the fitting formula, and the result of the fitting formula is the predicted power consumption.

[0069] For the following working conditions: =50 Hz =50 A、 =10、 =0.005、 =1.7 V、 =0.05 Ω, and based on this embodiment, the remaining factors in the fitting formula have been obtained, among which... =0.58 W =3.12×10 -4 , =1.35、 =1.2. Substituting the above parameters into the fitting formula, the power consumption of the high-voltage pulse circuit under this operating condition can be obtained. =14.76W.

[0070] Example 4 High-voltage power MOSFETs are subjected to rapid voltage stress and high-frequency switching transients in switching power supplies and high-frequency applications. This is due to the significant parasitic capacitance effect of power MOSFETs (such as...). C oss , C gd and on-resistance R DS(on) Due to the positive temperature coefficient characteristic of the material, traditional linear estimation methods based on datasheets often introduce large errors when predicting switching losses.

[0071] This embodiment measures the power consumption of a high-voltage pulse circuit based on MOSFET series connection, specifically... Figure 2 The series switch module 21 is used to measure power consumption, achieving high-precision measurement of the loss of the high-voltage pulse circuit. In this embodiment, the switch S in the series switch module 21... n (n=1,2,3…) can be a single solid-state switch or a switch module composed of multiple solid-state switches connected in series and parallel. All tests below are conducted at S… n The test was conducted using a single MOSFET, and the specific testing procedure is as follows: Step 1: Measurement and natural cooling experiment of constant power heating source to determine the thermal parameters of insulating liquid and static loss of high voltage pulse circuit.

[0072] The experimental environment for the measurement of the constant power heating source and the natural cooling experiment in this embodiment is the same as that in Example 3, and the heat balance equation is the same as that in Example 3, namely formula (1).

[0073] After obtaining the precise thermal parameters of the insulating liquid, the constant power heating source was removed, and the high-voltage pulse circuit was placed in the oil bath system. The high-voltage pulse circuit operated for a period of time under the conditions of 100Hz frequency, 50μs pulse width, and 50A current. After the module temperature reached a new thermal steady state, the steady-state temperature difference was recorded. ΔT At this point, the module's static power consumption is balanced with the system's heat dissipation capacity. Based on the calibrated thermal parameters, the module's static losses under this operating condition can be calculated. This calculation result includes additional losses generated by the voltage equalization resistors, gate drive resistors, etc., in the module's peripheral circuitry.

[0074] Step 2: Perform an equivalent power consumption test to determine the total power consumption of the high-voltage pulse circuit.

[0075] The method for measuring the total power consumption of a high-voltage pulse circuit is as follows: First, place the high-voltage pulse circuit in an oil bath system and set its operating conditions as follows: frequency 10Hz, pulse width 100μs, current 50A. After the circuit operates until the system temperature stabilizes, record the heating process of the oil bath system. This temperature-time curve will serve as the benchmark for subsequent equivalent comparisons. The system's heat capacity and heat dissipation coefficient have been calibrated. By fitting and analyzing the benchmark curve with the heating curve of the constant power heating source, its total power consumption can be accurately calculated.

[0076] Step 3: Equivalent test of the technical indicators of the switching module to determine the fitting formula between conduction loss and switching loss, which is the power consumption prediction model in this invention.

[0077] In this embodiment, the diode reverse recovery loss is extremely small. Based on the requirement to separate switching losses and conduction losses, power tests were conducted on the series MOSFET switching module under various operating conditions, including: current variation group, load variation group, frequency variation group, and high-frequency operating condition tests. Nonlinear fitting formulas for two types of losses and operating parameters were obtained through these four sets of tests.

[0078] (3) in, Total power consumption For static losses, For switching frequency, For switching energy coefficient, Drain current, The switching loss dynamic coefficient, The number of devices connected in series. Duty cycle, The on-resistance of the MOSFET at room temperature. This is the junction temperature loss factor.

[0079] In the fitting formula, the parasitic capacitance (such as...) is considered during the MOSFET switching process. C oss , C gd The switching loss deviation caused by this factor introduces a dynamic coefficient for switching loss. Corrections were made; simultaneously, measures were taken to address the issue of on-resistance at high temperatures and high switching frequencies. R DS(on) The additional conduction loss caused by the sharp increase introduces the junction temperature loss factor. Compensation and correction are performed. In this embodiment, the proposed nonlinear fitting formula achieves an average prediction error of less than 10% under a wide operating range of 10A-50A, 10Hz-1kHz, and 50μs-500μs, demonstrating high accuracy.

[0080] Using the fitting formula in this embodiment, the predicted power consumption of the high-voltage pulse circuit can be obtained by substituting the operating parameters under any operating condition into the fitting formula. In this embodiment, for the power consumption prediction of the high-voltage pulse circuit under any operating condition, the static loss... The switching energy coefficient has been determined in step 1. Switching loss dynamic coefficient With junction temperature loss factor As determined in step 3, the switching frequency will be... Drain current Number of series devices Duty cycle With the on-resistance of the MOSFET at room temperature Substitute the values ​​directly into the fitting formula, and the result of the fitting formula is the predicted power consumption.

[0081] For the following working conditions: =100 Hz =25A、 =5、 =0.005、 =0.05 Ω, and the remaining factors in the fitting formula have been obtained in this embodiment: =1.78 W =4.23×10 -4 , =1.6、 =0.011. Substituting the above parameters into the fitting formula, the power consumption of the high-voltage pulse circuit under this operating condition can be obtained. =21.44 W.

[0082] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An equivalent measurement method for power consumption of a high-voltage pulse circuit, characterized in that, Includes the following steps: S1: Obtain the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static loss of the high-voltage pulse circuit under test in the insulating liquid system. S2: Based on the operating condition parameters, hardware configuration parameters, device characteristic parameters, and static losses of the high-voltage pulse circuit under test, and in conjunction with the pre-built power consumption prediction model, determine the total power consumption of the high-voltage pulse circuit under test. The power consumption prediction model is constructed as follows: S21: A natural cooling experiment is conducted on the insulating liquid system using a constant power heating source to determine the thermal parameters of the insulating liquid system. Then, the high-voltage pulse circuit to be tested is placed in the insulating liquid system, and static operating conditions are applied to the high-voltage pulse circuit to be tested. Based on the temperature rise of the insulating liquid system and the thermal parameters, the static loss of the high-voltage pulse circuit to be tested is determined. S22: Run the high-voltage pulse circuit under test under a preset dynamic operating condition until the insulating liquid system reaches a stable temperature rise, record its total temperature change, and determine the equivalent total power consumption of the high-voltage pulse circuit under test based on the thermal parameters. S23: Based on the equivalent total power consumption and static loss, change the operating parameters of the high-voltage pulse circuit under test to conduct multiple power consumption tests, analyze the influence of different parameters on conduction loss and switching loss, and establish the power consumption prediction model.

2. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 1, characterized in that, The operating condition parameters include switching frequency, on-current, and duty cycle; the hardware configuration parameters include the number of series devices; and the device characteristic parameters include threshold voltage, dynamic on-resistance, thermal loss factor, and switching energy coefficient.

3. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 1, characterized in that, The thermal parameters include the overall heat dissipation coefficient and the pure heat capacity.

4. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 3, characterized in that, The comprehensive heat dissipation coefficient is obtained by: heating the insulating liquid system to a stable temperature using a constant power heat source and then turning it off; recording the temperature-time data of the insulating liquid system during the natural cooling process from the stable temperature to the initial reference temperature to obtain a natural cooling curve; and performing exponential fitting on the natural cooling curve to obtain the comprehensive heat dissipation coefficient.

5. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 4, characterized in that, The pure heat capacity is obtained by: heating the insulating liquid system with a constant power heating source, recording the temperature-time data during the process of rising from the initial reference temperature to a stable temperature, and obtaining the temperature rise curve; and using the temperature rise curve data and the comprehensive heat dissipation coefficient to obtain the pure heat capacity.

6. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 1, characterized in that, Before step S21, the method further includes: allowing the insulating liquid system to stand until its temperature is fully balanced with room temperature, and recording this balanced temperature as the initial reference temperature.

7. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 1, characterized in that, Step S23 is as follows: First, a baseline power consumption test is conducted under short pulse width conditions. Then, while keeping other operating parameters unchanged, a single operating parameter is changed to conduct a power consumption test. The impact of this parameter on the total loss is analyzed, and its calculation factor in the power consumption prediction model is determined. Finally, when the changes of multiple parameters can be combined into a single comprehensive parameter, this comprehensive parameter is used to construct the power consumption prediction model.

8. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 1, characterized in that, After step S23, the method further includes: using the power consumption prediction model to predict the power consumption under preset dynamic operating conditions, comparing the prediction results with the actual measurement results, evaluating the accuracy of the power consumption prediction model based on the error, and if the accuracy does not meet the preset conditions, returning to step S23 to add test conditions and continue to optimize the power consumption prediction model.

9. The equivalent measurement method for power consumption of a high-voltage pulse circuit according to claim 8, characterized in that, The preset condition is that the relative error between the predicted result and the actual measurement result is less than 10%.

10. An equivalent measurement device for the power consumption of a high-voltage pulse circuit, characterized in that, It includes a pulse parameter measurement module (1), a constant power heating source module (3), a load circuit module (4), an insulating liquid module (5), and a temperature measurement system module (6); the temperature sensing unit of the temperature measurement system module (6) is placed in the insulating liquid of the insulating liquid module (5); During measurement, the constant power heating source module (3) and the high voltage pulse circuit module (2) under test are independently immersed in the insulating liquid module (5); and the pulse parameter measurement module (1) and the load circuit module (4) are connected to the high voltage pulse circuit module (2) under test.

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