Low-loss aging test system based on single-phase input dynamic direct current feedback and control method

Abstract

The invention relates to a low-loss aging test system based on single-phase input dynamic direct current feedback and a control method. The low-loss aging test system comprises an aging test system and a tested unit, the aging test system comprises K1 energy conversion equipment, K2 energy conversion equipment and K3 energy conversion equipment which are connected through a high-voltage direct-current bus. The tested unit comprises a tested power supply, a power supply input end and a power supply output end; the input end of the power supply is connected with the output end of the K2 and is used for receiving the alternating current output by the DC-AC module, and the output end of the power supply is connected with the input end of the K3 and is used for transmitting the direct current after test processing to the DC-DC boosting module; and a closed-loop energy circulation link is formed between the aging test system and the tested unit. The device has the advantages of being high in power factor, low in harmonic content and high in energy conversion efficiency, cyclic utilization of energy is achieved, energy loss in the testing process is effectively reduced, the energy utilization efficiency is improved, the problem that the energy utilization rate of an alternating current feedback mode is low is solved, and remarkable economic benefits and environmental benefits are achieved.

Description

Technical Field

[0001] The present invention relates to power aging technology, and in particular to a low-loss aging test system with single-phase input dynamic DC feedback and a control method thereof. Background Art

[0002] In recent years, the concept of energy conservation and environmental protection has gained popularity. In the power supply industry, especially in switch-mode power supply enterprises, the application of energy feedback type aging loads has become increasingly widespread. Such loads have become a key development direction in the field of switch-mode power supply aging tests due to their ability to accurately simulate various load conditions and return electrical energy to the power grid without pollution.

[0003] Existing energy feedback type aging loads mostly adopt AC feedback technology. Although this technology solves the problem of electrical energy recovery to a certain extent, a series of problems have emerged in the actual application process. On the one hand, there are multiple electrical energy conversion losses in the AC system. On the other hand, AC feedback generates significant harmonics. To suppress harmonics, high costs need to be invested in installing complex harmonic suppression equipment, which undoubtedly increases the construction and maintenance costs of the system. At the same time, when the AC feedback type aging load is connected to the grid, it also faces the thorny problem of grid connection compatibility. Different grid environments have different requirements for parameters such as voltage, frequency, and phase, making it difficult for the AC feedback system to adapt to diverse grid access needs and restricting its large-scale popularization and application.

[0004] In contrast, the DC feedback type aging load test system exhibits significant advantages. It can effectively avoid problems such as high electrical energy conversion losses and large harmonics in the AC type system. In terms of electrical energy transmission, it has no skin effect, strong wire current-carrying capacity, no reactive power loss, and extremely high transmission efficiency; in terms of stability, there is no phase matching problem, the branch current is easy to accurately control, and the anti-interference ability is outstanding; in terms of the physical characteristics of the equipment, there is no need to equip large-capacity AC filter inductors or capacitors, the volume is small, and the power density is greatly improved. Summary of the Invention

[0005] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a low-loss aging test system with single-phase input dynamic DC feedback and a control method thereof, which realizes the recycling of energy, effectively reduces the energy loss during the test process, improves the energy utilization efficiency, solves the problem of low energy utilization rate of the AC feedback method, and has significant economic and environmental benefits.

[0006] The above object of the present invention is achieved through the following technical solutions:

[0007] On the one hand, the present invention discloses a low-loss aging test system with single-phase input dynamic DC feedback, including an aging test system and a unit under test;

[0008] The aging test system includes a K1 energy conversion device, a K2 energy conversion device and a K3 energy conversion device connected by a high-voltage DC bus, wherein the K1 energy conversion device is an AC-DC module, the K2 energy conversion device is a DC-AC module, and the K3 energy conversion device is a DC-DC boost module;

[0009] The unit under test includes a power supply under test, and two ends of the power supply under test are provided with a power input end and a power output end; the power input end is connected to the output end of the K2 energy conversion device, and is used to receive the alternating current output by the DC-AC module, and the power output end is connected to the input end of the K3 energy conversion device, and is used to transmit the direct current after the test process to the DC-DC boost module;

[0010] A closed-loop energy circulation link is formed between the aging test system and the unit under test.

[0011] Through the above technical solution, electric energy recycling and conversion loss reduction are achieved, achieving energy conservation and consumption reduction; with K1 adjusting the mains input power according to system requirements, K2 providing stable AC input, and K3 realizing electric energy feedback, the entire DC feedback aging test system forms a closed-loop energy circulation link and is not directly connected to the power grid. This not only greatly improves energy utilization efficiency, reduces system operating costs, and reduces dependence on external power supplies, but also completely avoids the complex problems of AC feedback such as grid synchronization, harmonic filtering, and power factor correction; at the same time, the stable closed-loop operation mechanism ensures the stability of the high-voltage DC bus voltage, provides a reliable working environment for each module in the system, reduces the risk of equipment failure, and extends the service life of the equipment.

[0012] As a further technical solution of the present invention: the AC-DC module adopts a bridge rectifier circuit to compensate for the circulation loss of the aging test system and maintain the voltage stability of the high-voltage DC bus.

[0013] Through the above technical solution, the bridge rectifier circuit has a simple structure and low cost, effectively converting AC power into DC power, while compensating for system circulation losses and maintaining bus voltage stability, ensuring the stable operation of the entire aging test system, providing stable and reliable DC power supply for other modules, and improving the accuracy and repeatability of test results.

[0014] The DC-AC module uses a full-bridge inverter circuit module to directly convert the voltage of the high-voltage DC bus into an adaptive AC power, and is responsible for providing AC input for the power supply under test.

[0015] Through the above technical solution, the full-bridge inverter outputs a pure sine wave, accurately simulates the real power grid environment, draws power from the high-voltage DC bus, eliminates the intermediate energy storage link, and reduces the circuit size and weight.

[0016] As a further technical solution of the present invention: the DC-DC boost module adopts a three-stage boost circuit, and the three-stage boost circuit boosts the direct current output by the unit under test to the same level as the bus voltage, and then feeds back the boosted direct current to the high-voltage DC bus without passing through the power grid.

[0017] Through the above technical solution, the three-stage Boost boost circuit can flexibly adjust the boost ratio, adapt to the boost requirements of direct current in different voltage ranges, be compatible with a variety of power source tests, efficiently boost the direct current output by the unit under test, boost it to the same level as the bus voltage and feed it back to the bus, realizing the effective recycling of energy and improving the overall energy utilization rate of the system.

[0018] As a further technical solution of the present invention: the K1 energy conversion device dynamically adjusts the power at the mains input end and absorbs corresponding energy according to the voltage output by the K3 energy conversion device to maintain the voltage stability of the high-voltage DC bus.

[0019] Through the above technical solution, the energy utilization efficiency is significantly improved, the real-time requirements of the system are accurately matched, and energy waste is avoided; the equipment in the system is effectively protected, the failure risk caused by voltage fluctuations is reduced, and the service life of the equipment is prolonged; at the same time, a stable environment is provided for the aging test, the test accuracy and reliability are improved, and the accuracy and persuasiveness of the test data are ensured.

[0020] On the other hand, the present invention also discloses a control method for a low-loss aging test system based on single-phase input dynamic DC feedback, including two test methods. The first test method includes the following steps: simultaneously performing aging tests on a plurality of the units under test in parallel through one of the aging test systems. The input ends of the plurality of the power supplies under test are all connected to the output end of the DC-AC module in the aging test system, and the output ends are all connected to the input end of the DC-DC boost module in the aging test system;

[0021] The second test method includes the following steps: Aging tests are performed on multiple units under test by connecting multiple of the aging test systems in series. The AC-DC module of the first aging test system is connected to the mains power supply; the output end of the high-voltage DC bus is directly connected to the input end of the DC bus of the next aging test system; each aging test system is connected in series through the high-voltage DC bus to form a chain structure; the input end of each power supply under test is respectively connected to the output end of the DC-AC module in the aging test system where it is located, and receives the alternating current output by the corresponding DC-AC module; the output end of each power supply under test is connected to the input end of the DC-DC boost module in the aging test system where it is located, and the direct current boosted by the DC-DC boost module is fed back to the high-voltage DC bus, thereby realizing the aging test of multiple power supplies under test by connecting multiple aging test systems in series.

[0022] Through the above technical solutions, two test methods are provided to meet the test requirements of power supplies under test of different scales and types. The parallel test method can test multiple power supplies under test simultaneously, improving the test efficiency; the series test method can achieve the coordinated operation of multiple aging test systems, expanding the test scale, and providing an efficient solution for the power supply test in large-scale production.

[0023] As a further technical solution of the present invention: A control method for low-loss aging test based on single-phase input dynamic DC feedback includes the configuration of test parameters of the power supply under test and control means for efficient transmission of test data; in terms of test time setting, any test duration can be customized according to actual test requirements; in terms of test data transmission, the test data is transmitted through RS485 for data transfer.

[0024] Through the above technical solutions, customizing the test duration enables testers to flexibly arrange the test time according to the characteristics of the power supply under test and the test purpose, improving the pertinence and effectiveness of the test; using RS485 for data transmission has the characteristics of long transmission distance and strong anti-interference ability, ensuring that the test data can be accurately and stably transmitted, providing a reliable basis for subsequent data analysis and processing.

[0025] As a further technical solution of the present invention: The test data includes total loss power, total loss rate, and cyclic feedback power, and their calculation formulas are as follows.

[0026] The calculation formula for total loss power is:

[0027] The calculation formula for the loss rate is: η total = η AC-DC × η DC-AC × η DUT × η DC-DC ;

[0028] The calculation formula for the total loss rate is: Total loss rate = 1 - η total ;

[0029] The calculation formula for the circulating feedback power is: P 循环 = P0 × η DC-DC ;

[0030] where P0 is the output power of the DUT.

[0031] Through the above technical solutions, three core parameters, namely the total loss power, the total loss rate, and the circulating feedback power, are monitored in real time, and a closed-loop energy efficiency management system of "measurement - analysis - optimization" is constructed. Through the measurement system of the total loss power, the energy loss situation during the operation process can be accurately grasped, providing a clear direction for energy-saving optimization; secondly, through the quantitative evaluation of the loss rate, the energy utilization efficiency is intuitively reflected, supporting the performance comparison between systems; based on the dynamic monitoring of the circulating feedback power, the degree of energy recycling and reuse of the system is measured, the working parameters of the DC-DC module and the system energy management strategy are optimized, the energy recycling efficiency is enhanced, the dependence on external mains input is reduced, the system operation cost is reduced, the energy-saving characteristics and sustainability of the system are improved, and the level of energy recycling and utilization is effectively improved.

[0032] In summary, the present invention includes at least one of the following beneficial technical effects:

[0033] 1. The present invention discloses a low-loss aging test system and control method based on single-phase input dynamic DC feedback. By designing the aging test system as a closed-loop energy circulation link formed by an AC-DC module, a DC-AC module, a DC-DC boost module, and a unit under test connected by a high-voltage DC bus, the efficient recycling and utilization of the output energy of the power supply under test are realized, the system operation loss is greatly reduced, and a low-energy-consuming aging test system is constructed;

[0034] 2. The present invention discloses a low-loss aging test system and control method based on single-phase input dynamic DC feedback. By adopting a bridge rectifier circuit in the AC-DC module and dynamically regulating the mains input power in combination with the real-time voltage feedback of the K3 energy conversion device, the accurate and stable control of the high-voltage DC bus voltage is realized, and at the same time, the energy loss generated due to line and module internal resistance during the system circulation process is compensated, ensuring the stable operation of each module and the test accuracy;

[0035] 3. The present invention discloses a low-loss aging test system and control method based on single-phase input dynamic DC feedback. By setting a single-system parallel test method and a multi-system series test method, it realizes flexible adaptation to power supplies under test with different quantities and types. The parallel mode can test multiple units under test simultaneously to improve the single-unit test efficiency, and the series mode can expand the system scale to meet the requirements of large-scale aging tests, significantly enhancing the versatility and engineering practicability of the test scheme. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 FIG. is a low-loss aging test system with single-phase input dynamic DC feedback in Embodiment 1 of the present invention.

[0037] Figure 2 FIG. is a diagram of the parallel test method for a single aging test system in Embodiment 1 of the present invention.

[0038] Figure 3 FIG. is a diagram of the series test method for multiple aging test systems in Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0040] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "top / bottom end", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "provided with", "sheathed / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0042] Embodiment 1:

[0043] Reference Figure 1 , a low-loss aging test system based on single-phase input dynamic DC feedback disclosed by the present invention, includes an aging test system and a unit under test.

[0044] The aging test system includes a K1 energy conversion device, a K2 energy conversion device, and a K3 energy conversion device connected to a high-voltage DC bus. The K1 energy conversion device is an AC-DC module, the K2 energy conversion device is a DC-AC module, and the K3 energy conversion device is a DC-DC boost module.

[0045] The unit under test includes a power input terminal, a power supply under test, and a power output terminal. The power input terminal is connected to the output terminal of the K2 energy conversion device to receive the alternating current output by the DC-AC module. The power output terminal is connected to the input terminal of the K3 energy conversion device to output the direct current after test processing to the DC-DC boost module. A closed-loop energy circulation link is formed between the aging test system and the unit under test.

[0046] The AC-DC module adopts a bridge rectifier circuit, which is responsible for compensating the circulating loss of the aging test system and maintaining the voltage stability of the high-voltage DC bus. The high-voltage DC bus is connected to the mains input terminal through the K1 energy conversion device. The K1 energy conversion device dynamically adjusts the power of the mains input terminal according to the voltage output by the K3 energy conversion device to maintain the voltage stability of the DC bus.

[0047] The DC-AC module adopts a full-bridge inverter circuit module, which directly converts the voltage of the DC bus into a suitable alternating current and is responsible for providing alternating current input for the power supply under test.

[0048] Furthermore, the full-bridge inverter circuit module can use silicon carbide power devices. Compared with traditional silicon-based devices, silicon carbide devices have higher switching frequencies and lower on-resistances, which can significantly improve the inverter efficiency, reduce the volume and weight of the circuit. Software can also be upgraded. By introducing advanced pulse width modulation (PWM) control technologies, such as space vector pulse width modulation (SVPWM), the waveform quality of the output alternating current can be further optimized and the harmonic content can be reduced.

[0049] The DC-DC boost module adopts a three-stage boost circuit to boost the direct current output by the unit under test to the same level as the voltage of the high-voltage DC bus, and then feeds back the boosted direct current to the high-voltage DC bus without passing through the power grid, forming a closed loop. Its DC-DC boost module is responsible for feeding back the energy output by the DUT to the high-voltage DC bus without passing through the power grid, and there is no need to consider issues such as grid connection compatibility.

[0050] In addition, the aging test system and the load unit are communicatively connected via CANBus. The load unit is a key component for simulating the device under test, such as the load carried by the power supply under test during actual operation, and includes various types of load elements, such as resistors, inductors, capacitors, etc. Different load modes, such as constant current, constant voltage, and constant power loads, are set according to the test requirements to simulate various load scenarios of the power supply under test in actual applications, such as light load, full load, overload, etc., and to test performance indicators of the power supply under test, such as stability, efficiency, temperature rise, and output accuracy, under different load conditions.

[0051] Refer to Figure 2 , in this embodiment, a parallel mode test method is adopted. An aging test is carried out on multiple units under test in parallel by an aging test system at the same time. The input ends of multiple power supplies under test are all connected to the output end of the DC-AC module in the aging test system, and the power output ends are all connected to the input end of the DC-DC boost module in the aging test system.

[0052] The parallel mode test method is applicable when independent aging tests need to be carried out on multiple power supplies at the same time. Each power supply module can obtain the same voltage and work independently of each other without mutual influence. In this way, aging tests on multiple different power supplies can be carried out at the same time, improving the test efficiency. At the same time, it is also convenient to monitor and evaluate the performance of each power supply separately. At the same time, multiple power supply modules in parallel can provide a larger total power output. If the power of a single power supply module cannot meet the requirements of the aging test, by paralleling multiple power supply modules, their powers can be superimposed to meet the high-power requirements of the test. For example, when carrying out aging tests on some high-power industrial power supplies, a relatively high power may be required to simulate the load conditions during actual operation. In this case, the method of paralleling multiple power supply modules can well solve the problem of insufficient power.

[0053] The specific operation steps of the parallel mode test method are as follows:

[0054] First, connect the system. Connect the input ends of the power supplies under test of multiple units under test to the output end of the DC-AC module in the aging test system respectively, and the output ends are all connected to the input end of the DC-DC boost module in the aging test system. At the same time, connect the high-voltage DC bus to the mains input end through the K1 energy conversion device.

[0055] During the connection of the system, specifically as follows, the AC-DC module converter adopts the most common bridge rectifier topology to compensate for the loss of the high-voltage DC bus by connecting to the mains power supply, and always stabilizes the high-voltage DC bus voltage at 310V; the DC-AC module adopts a full-bridge inverter topology to invert the stable 310V DC high-voltage DC bus voltage to the AC voltage required by the unit under test (such as 220VAC), and freely changes the output AC voltage by adjusting its own sampling resistance; the power input terminal is connected to the output terminal of the aging test system. When the power output terminal is connected to the power input terminal of the DC-DC boost module. The DC-DC boost module can automatically identify according to the range of DC power output by the power supply under test. Among them, for the DC-DC boost module; when the DC voltage < 48V, three groups of boosts are connected in series; when 48V < DC voltage < 80V, two groups of boosts are connected in series; when 80V < DC voltage, one group of boosts is connected in series. At this time, the DC-DC boost module outputs fluctuating 380VDC to the high-voltage DC bus terminal. The output terminal of the AC-DC module compensates the voltage by detecting the output voltage of the DC-DC boost module, so that the high-voltage DC bus remains continuously and stably at 380V.

[0056] Then set the parameters. According to the specifications and test requirements of the power supply under test, set test parameters such as the test time through the human-machine interface. For example, if the power supply under test is a power supply with a rated voltage of 220V and a rated power of 100W, the test time can be set to 24 hours.

[0057] Next, start the aging test system. The AC-DC module converts the mains power into DC power to maintain the voltage stability of the high-voltage DC bus. The DC-AC module inverts the high-voltage DC bus voltage into a suitable AC power to provide AC input for multiple power supplies under test at the same time.

[0058] Enter the test process. After receiving the AC input, the power supply under test starts to work and delivers the output DC power to the DC-DC boost module. The DC-DC boost module uses a three-stage boost circuit to boost the DC power to the same level as the high-voltage DC bus voltage, and then feeds it back to the high-voltage DC bus.

[0059] During the test, the K3 energy conversion device monitors the output voltage of the power supply under test in real time and feeds it back to the AC-DC module. The AC-DC module dynamically adjusts the power at the mains input end according to the feedback voltage to maintain the high-voltage DC bus voltage stable at 380V. To accurately adjust the high-voltage DC bus voltage, a PID controller is set in the AC-DC module to collect the actual value of the high-voltage DC bus voltage in real time, calculate the deviation between the actual value and the preset voltage value, generate an adjustment signal based on the PID control algorithm, and control the compensation power of the AC-DC module to keep the voltage of the high-voltage DC bus stable within the preset range. The specific algorithm can adopt the PID control formula based on the deviation of the high-voltage DC bus voltage, and calculate P through the formula 补偿 , P 补偿 As a quantified compensation instruction to guide the AC-DC module to adjust the output. For example, when the output fluctuation of the DC-DC boost module causes the high-voltage DC bus voltage to be lower than 380V, it will drive the AC-DC module to increase the output energy, and vice versa, ultimately keeping the high-voltage DC bus voltage continuously stable at 380V, ensuring stable power supply for the backend devices, and improving the system reliability and energy efficiency.

[0060] The PID control based on the bus voltage deviation, and its calculation formula is:

[0061]

[0062] Where: K p , K i , K d are gains, V ref is the specified reference voltage, and V DC is the output voltage.

[0063] All the above specific voltage values can be changed according to the actual situation.

[0064] At the same time, data transmission and monitoring are carried out. The data during the test, such as the total loss power, the voltage and current of the power supply under test, etc., are transmitted to the monitoring terminal through the RS485 communication interface. The operator can monitor the test data in real time to ensure the normal progress of the test.

[0065] Finally, when the test is over, when the preset test time is reached, the system automatically stops the test and disconnects each module from the high-voltage DC bus.

[0066] Furthermore, to control the test accuracy of the test system, by calculating the total loss power and the total loss rate, the energy loss distribution of each link (AC-DC module, DC-AC module, DC-DC boost module, DUT module) of the test system is further clarified, the inefficient links are located, and data support is provided for optimizing the system design and reducing energy consumption.

[0067] The specific calculation of the loss is as follows:

[0068] The total efficiency is: total =η AC-DC ×η DC-AC ×η DUT ×η DC-DC .

[0069] Total loss rate: Total loss rate = 1-η total .

[0070] The loop feedback power is: P 循环 =P0×η DC-DC , where P0 is the DUT output power.

[0071] The total power loss of the system is:

[0072] The above formula is used to calculate system voltage control and energy efficiency evaluation. PID regulation is used to maintain the voltage stability of the high-voltage DC bus. The system energy efficiency is quantified with the help of loss calculation, providing a basis for optimizing design and improving performance.

[0073] Since this test system automatically senses and adjusts the voltage changes in each link, when testing the power supply, the power supply under test is directly connected to the test equipment. The specific loss example is calculated as follows.

[0074] For example: AC-DC 98%; DC-AC 95%; η DUT 93%; DC-DC 97%;

[0075] After the unit under test is connected to the aging test system, the total loss of DC feedback can be calculated based on the efficiency.

[0076] For example, if the DUT output power P0 is 5KW:

[0077] DC-DC boost module feedback power:

[0078] P 回馈 =P0×η DC-DC =5kw×97%=4.85kw;

[0079] DUT input power is DC-AC module output power:

[0080]

[0081] DC-AC module input power is DC bus power:

[0082]

[0083] The input power of the AC-DC module, i.e., the power supplement from the mains electricity:

[0084]

[0085] Total loss power:

[0086] ΔP = P 市电输入 = 0.826 kw;

[0087] Total loss rate:

[0088]

[0089] Compared with the AC feedback, the DC feedback of the present invention can make the total loss rate of the entire aging test system lower than 20%.

[0090] The working mode of the present invention is to utilize power electronic conversion technology to recycle the output energy of the power supply under test in a cyclic manner on the premise of completing the test power experiment, which not only saves energy but also does not generate a large amount of heat, avoiding the problem of the environmental temperature rise in the test site. Therefore, there is no need to use a large-volume resistance box and cooling equipment, saving the installation space. At the same time, due to the adoption of the energy feedback mode, there is no need to equip a large power supply capacity in the test site, reducing the cost of the power supply capacity.

[0091] Embodiment 2:

[0092] Refer to Figure 3 , different from Embodiment 1, this embodiment adopts an energy feedback type power supply aging device with multiple aging test units connected in series, which is suitable for the situation where a large number of power supplies under test need to be synchronously aged and the power of a single aging test system cannot meet the requirements. For example, when studying the lifespan and reliability of power supplies of different brands or different designs under the same aging conditions, the series connection mode can provide a more accurate comparative test environment.

[0093] The specific operation steps of the series mode test method are as follows:

[0094] First, connect the system. Connect multiple aging test systems in series in sequence. The AC-DC module of the first aging test system is connected to the mains electricity, and its high-voltage DC bus is connected to the input end of the AC-DC module of the next aging test system. Each aging test system is respectively connected to the corresponding number of units under test, that is, the input end of each power supply is respectively connected to the output end of the DC-AC module in its aging test system, and the output end is connected to the input end of the DC-DC boost module in its aging test system.

[0095] Then set the parameters. According to the specifications of the power supply under test and the test requirements, uniformly set test parameters such as the test time. For example, if it is necessary to conduct an aging test on 100 power supplies with a rated voltage of 220V and a rated power of 100W, the test time can be set to 48 hours.

[0096] Next, start the entire series test system. The AC-DC module of the first aging test system converts the commercial power into direct current to provide power for the subsequent series-connected aging test systems. The DC-AC module in each aging test system inversely converts the high-voltage DC bus voltage into a suitable alternating current to provide AC input for the power supplies under test connected thereto.

[0097] During the test process, each power supply under test starts to work after receiving the AC input, and delivers the output direct current to the DC-DC boost module of the aging test system where it is located. The DC-DC boost module boosts the direct current to the same level as the high-voltage DC bus voltage, and then feeds it back to the high-voltage DC bus of the aging test system where it is located. During the test, the K3 energy conversion device of each aging test system monitors the output voltage of the power supply under test connected thereto in real time and feeds it back to the corresponding AC-DC module. The AC-DC module dynamically adjusts the power at the commercial power input end according to the feedback voltage to maintain the voltage stability of its respective high-voltage DC bus.

[0098] At the same time, data transmission and monitoring are carried out. The test data in each aging test system, such as the total loss power, the voltage and current of the power supply under test, etc., are transmitted to the monitoring terminal through the RS485 communication interface, and the operator can monitor the operation status and test data of the entire series test system in real time.

[0099] Finally, the test ends. When the preset test time is reached, the system automatically stops the test.

[0100] The embodiments of this specific implementation manner are all preferred embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A low-loss aging test system based on single-phase input dynamic DC feedback, characterized in that, It includes an aging test system and a unit under test; The aging test system includes a K1 energy conversion device, a K2 energy conversion device, and a K3 energy conversion device connected by a high-voltage DC bus. Among them, the K1 energy conversion device is an AC-DC module, the K2 energy conversion device is a DC-AC module, and the K3 energy conversion device is a DC-DC boost module; The unit under test includes a power supply under test, and power input terminals and power output terminals are provided at both ends of the power supply under test; The power input terminal is connected to the output terminal of the K2 energy conversion device to receive the alternating current output by the DC-AC module, and the power output terminal is connected to the input terminal of the K3 energy conversion device to transmit the direct current after test processing to the DC-DC boost module; A closed-loop energy circulation link is formed between the aging test system and the unit under test.

2. The low-loss aging test system based on single-phase input dynamic DC feedback according to claim 1, wherein The AC-DC module adopts a bridge rectifier circuit, which is responsible for compensating the circulation loss of the aging test system and maintaining the voltage stability of the high-voltage DC bus.

3. The low-loss aging test system based on single-phase input dynamic DC feedback according to claim 1, characterized in that, The DC-AC module adopts a full-bridge inverter circuit module to directly convert the voltage of the high-voltage DC bus into a suitable alternating current, which is responsible for providing AC input for the power supply under test.

4. The low-loss aging test system based on single-phase input dynamic DC feedback according to claim 1, characterized in that, The DC-DC boost module adopts a three-stage boost circuit. The three-stage boost circuit boosts the direct current output by the unit under test to the same level as the voltage of the high-voltage DC bus, and then feeds back the boosted direct current to the high-voltage DC bus without passing through the power grid.

5. The low-loss aging test system based on single-phase input dynamic DC feedback according to claim 1, wherein The K1 energy conversion device dynamically adjusts the power of the mains input terminal and absorbs the corresponding energy according to the voltage output by the K3 energy conversion device to maintain the voltage stability of the high-voltage DC bus.

6. The control method of the low-loss aging test system based on single-phase input dynamic DC feedback according to any one of claims 1-5, characterized in that, It includes two test methods, The first test method includes the following steps: Aging tests are simultaneously carried out on multiple units under test in parallel through one aging test system. The input terminals of multiple power supplies under test are all connected to the output terminal of the DC-AC module in the aging test system, and their output terminals are all connected to the input terminal of the DC-DC boost module in the aging test system; The second test method includes the following steps: Multiple aging test systems are connected in series to carry out aging tests on multiple units under test. The AC-DC module of the first aging test system is connected to the mains; The output terminal of the high-voltage DC bus is directly connected to the input terminal of the DC bus of the next aging test system; Each aging test system is connected in series through the high-voltage DC bus to form a chain structure; The input terminal of each power supply under test is respectively connected to the output terminal of the DC-AC module in its corresponding aging test system to receive the alternating current output by the corresponding DC-AC module; The output terminal of each power supply under test is connected to the input terminal of the DC-DC boost module in its corresponding aging test system, and the direct current boosted by the DC-DC boost module is fed back to the high-voltage DC bus, so as to realize the aging test of multiple power supplies under test by connecting multiple aging test systems in series.

7. The control method of the low-loss aging test system based on single-phase input dynamic DC feedback according to claim 6, characterized in that, It includes the configuration of the test parameters of the power supply under test and the control means for efficient transmission of test data; In terms of test time setting, any test duration can be customized according to the actual test requirements; In terms of test data transmission, the test data is transmitted through RS485.

8. The control method of the low-loss aging test system based on single-phase input dynamic DC feedback according to claim 7, wherein The test data includes the total loss power, the total loss rate, and the cyclic feedback power, and their calculation formulas are as follows. The calculation formula for the total loss power ΔP is as follows: The calculation formula for the loss rate is: η total = η AC-DC × η DC-AC × η DUT × η DC-DC ; The calculation formula for the total loss rate is: Total loss rate = 1 - η total ; The calculation formula for the cyclic feedback power is: P 循环 = P0 × η DC-DC ; Where P0 is the output power of the DUT.

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