Load system compatible with wide input voltage and adjustable in current and method for adjusting load

Abstract

The invention relates to the technical field of electrical tests, in particular to a load system compatible with wide input voltage and adjustable in current and a load adjusting method. According to the load system, the input side of a low-voltage input switch is connected with a live wire port; the input side of the high-voltage input switch is connected in parallel with the input side of the low-voltage input switch and is connected with the live wire port; one side T of the interconnection switch is connected to the output side of the high-voltage input switch, and the other side of the interconnection switch is connected with the zero line port; one ends of the high-voltage side impedance units are connected in parallel and then connected with the output side of the high-voltage input switch, the other ends of the high-voltage side impedance units are connected with one ends of the low-voltage side impedance units respectively, the other ends of the low-voltage side impedance units are connected with the high-voltage side impedance units respectively, and the other ends of the low-voltage side impedance units are connected in parallel and then connected with the zero line port. And one end of the grouping switch is connected with the output side of the low-voltage input switch after being connected in parallel, and the other end of the grouping switch is T-connected to a connection point between each group of high-voltage side impedance unit and low-voltage side impedance unit.

Description

Technical Field

[0001] The present application relates to the field of electrical testing technology, and in particular to a load system compatible with a wide input voltage and adjustable current, and a method for adjusting the load. Background Art

[0002] In the process of research, production and testing of various power supply equipment such as transformers, converters, battery packs, chargers, etc., it is usually necessary to conduct load tests to detect and assess the equipment's load capacity and performance indicators and reliability under different working conditions, so it is necessary to configure a load system that matches the characteristics of the object being tested. However, in production practice, since the output voltage and current of different types and models of equipment may vary greatly, the load system needs to be able to adapt to different voltage inputs and flexible and adjustable load currents.

[0003] In response to the load test requirements under different input voltages, the traditional response method is to configure the load impedance according to the high input voltage, and then operate the high voltage impedance unit under a lower input voltage. Since the output current of a general impedance load unit is proportional to its port voltage, when the input voltage is low, its load current and power will be much lower than the rated value. For example, for the same load impedance value, when the rated voltage is 400V, its maximum output current when operating under 100V conditions is only 25% of the rated value, and the output power is only 1 / 16 of the rated value. As a result, the actual current and power of the load system at low input voltage are difficult to reach the expected rated assessment current, thus failing to meet the test requirements; or in order to be compatible with low input voltage operating conditions, the load impedance is configured according to the rated current output under low voltage conditions, so that a high-power load system with a rated power much higher than the actual power needs to be configured. For example, in order to be compatible with a load power of up to 100kW under both 200V and 100V input voltages, a rated 200V / 400kW load box needs to be configured, which not only wastes power units, but also leads to high volume and cost of load power units. Another method is to use a plurality of load unit monomers in series to adapt to different input voltages, but this method is not convenient for flexible adjustment of load current, and often requires a large amount of temporary wiring, which is inefficient. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a load system that is compatible with a wide input voltage and has adjustable current, which can quickly adjust to adapt to different input voltage and load current requirements without increasing the rated power of the load, thereby meeting the testing requirements of different devices.

[0005] In order to achieve the above object, an embodiment of the present application provides a load system compatible with a wide input voltage and adjustable current, the load system comprising:

[0006] A low voltage input switch, the input side of the low voltage input switch is connected to the live wire port;

[0007] A high voltage input switch, the input side of the high voltage input switch is connected in parallel with the input side of the low voltage input switch and is connected to the live wire port;

[0008] Tie switch, one side of the tie switch is connected to the output side of the high voltage input switch, and the other side is connected to the neutral line port;

[0009] A plurality of groups of high-voltage side impedance units, each group of high-voltage side impedance units includes an impedance load and a corresponding high-voltage impedance load switch, one end of the plurality of groups of high-voltage side impedance units is connected in parallel to the output side of the high-voltage input switch, and the other end is respectively connected to one end of the plurality of groups of low-voltage side impedance units;

[0010] Multiple groups of low-voltage side impedance units, each group of low-voltage side impedance units includes an impedance load and a corresponding low-voltage impedance load switch, one end of the multiple groups of low-voltage side impedance units is respectively connected to the multiple groups of high-voltage impedance units, and the other end is connected in parallel to the neutral line port;

[0011] A grouping switch, one end of which is connected in parallel to the output side of the low-voltage input switch, and the other end is respectively connected to the connection point between each group of high-voltage side impedance units and low-voltage side impedance units.

[0012] In an embodiment of the present application, the load system includes: a high-voltage input switch, a low-voltage input switch, a group switch, and an anti-mistake locking current is arranged between the connecting switches.

[0013] In an embodiment of the present application, an interlocking circuit is provided between the high-voltage input switch and the low-voltage input switch to prohibit the high-voltage input switch and the low-voltage input switch from being closed at the same time; an interlocking circuit is provided between the high-voltage input switch and the grouping switch to prohibit the high-voltage input switch and the grouping switch from being closed at the same time; an interlocking circuit is provided between the high-voltage input switch and the connecting switch to prohibit the high-voltage input switch and the connecting switch from being closed at the same time.

[0014] In an embodiment of the present application, the load system further includes: an overvoltage protection device, one end of the overvoltage protection device is connected to one side of the tie switch, and the other end is connected to the neutral line port.

[0015] In an embodiment of the present application, for any group of high-voltage side impedance units, the rated voltage, rated current and rated impedance of the high-voltage side impedance unit and the low-voltage side impedance unit connected to the high-voltage side impedance unit are the same.

[0016] In an embodiment of the present application, for any group of high-voltage side impedance units and low-voltage side impedance units, the minimum current of the impedance unit is less than or equal to a preset minimum load current, wherein the preset minimum load current is determined based on the minimum input voltage; the sum of the total currents of all impedance units is greater than or equal to a preset maximum load current, wherein the preset maximum load current is determined based on the maximum input voltage.

[0017] A second aspect of the present application provides a method for regulating a load, which is applied to a load system compatible with a wide input voltage and adjustable current as described above, and the method comprises:

[0018] When the input voltage is lower than the preset voltage, the low-voltage input switch, the grouping switch and the connecting switch are controlled to close, and the high-voltage input switch is opened, so that multiple groups of high-voltage side impedance units are connected in parallel with the low-voltage side impedance units.

[0019] In an embodiment of the present application, the method includes: respectively controlling the high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units so that the load of the adjustable load system is within a preset numerical range, wherein the preset numerical range is determined according to the input voltage.

[0020] In an embodiment of the present application, the method also includes: when the input voltage is higher than a preset voltage, controlling the low-voltage input switch, the group switch and the connecting switch to be disconnected, and the high-voltage input switch to be closed, so that the high-voltage side impedance unit is connected in series with the low-voltage side impedance unit.

[0021] In an embodiment of the present application, the method also includes: respectively controlling the high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units, so that the load of the adjustable load system is within a preset numerical range, wherein the preset numerical range is determined according to the input voltage.

[0022] Through the above technical solution, the same maximum output power can be obtained under two different input voltages, thereby avoiding the situation where the power drops seriously under low input voltage and the power rated power utilization rate is extremely low, improving the utilization rate of power components, and helping to reduce the volume, weight and cost of the load system, thereby improving economy. When switching different input voltages, only a small number of isolating switches need to be adjusted, which is convenient and quick, avoiding tedious wiring changes and high efficiency. An anti-misoperation interlocking system is provided to prevent abnormal faults caused by operator misoperation from causing equipment damage.

[0023] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0025] Figure 1 A schematic diagram of the structure of a load system compatible with a wide input voltage and adjustable current according to an embodiment of the present application is shown;

[0026] Figure 2 A schematic diagram of the operating states of the switch units of a load system compatible with a wide input voltage and adjustable current according to an embodiment of the present application when the input is connected to a relatively low voltage and with a maximum load is shown;

[0027] Figure 3 The schematic diagram shows the operating states of the switch units of a load system compatible with a wide input voltage and adjustable current according to an embodiment of the present application when the input is connected to a higher voltage and carries a 50% load.

[0028] Description of Reference Numerals

[0029] K1: low voltage input switch; K2: high voltage input switch; K3: contact switch; K4: group switch; A: live wire port; N: neutral wire port; R11, R21, R31, R41: high voltage side impedance unit; R12, R22, R32, R42: low voltage side impedance unit; K11, K21, K31, K41: high voltage impedance load switch; K12, K22, K32, K42: low voltage impedance load switch. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0031] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0033] Figure 1 The structure diagram of a load system compatible with a wide input voltage and adjustable current according to an embodiment of the present application is schematically shown. Figure 1 As shown, the embodiment of the present application provides a load system compatible with a wide input voltage and adjustable current, including: a low-voltage input switch K1, the input side of the low-voltage input switch K1 is connected to the live wire port A;

[0034] High voltage input switch K2, the input side of the high voltage input switch K2 is connected in parallel with the input side of the low voltage input switch K1, and is connected to the live wire port A;

[0035] A contact switch K3, one side T of the contact switch K3 is connected to the output side of the high voltage input switch K2, and the other side is connected to the neutral line port N;

[0036] A plurality of groups of high-voltage side impedance units, each group of high-voltage side impedance units includes an impedance load and a corresponding high-voltage impedance load switch, one end of the plurality of groups of high-voltage side impedance units is connected in parallel to the output side of the high-voltage input switch K2, and the other end is respectively connected to one end of the plurality of groups of low-voltage side impedance units;

[0037] Multiple groups of low-voltage side impedance units, each group of low-voltage side impedance units includes an impedance load and a corresponding low-voltage impedance load switch, one end of the multiple groups of low-voltage side impedance units is respectively connected to the multiple groups of high-voltage impedance units, and the other end is connected in parallel to the neutral line port N;

[0038] The grouping switch K4 has one end connected in parallel to the output side of the low voltage input switch K1, and the other end connected to the connection point between each group of high voltage side impedance units and low voltage side impedance units.

[0039] For example Figure 1As shown, it is assumed that the load system compatible with a wide input voltage and adjustable current includes four groups of high-voltage side impedance units R11, R21, R31, R41 and four groups of low-voltage side impedance units R12, R22, R32, R42, each group of high-voltage side impedance units includes an impedance load and a corresponding high-voltage impedance load switch K11, K21, K31, K41, one end of the four groups of high-voltage side impedance units are connected in parallel to the output side of the high-voltage input switch K2, and the other end is respectively connected to one end of the four groups of low-voltage side impedance units, each group of low-voltage side impedance units includes an impedance load and a corresponding low-voltage impedance load switch K12, K22, K32, K42, one end of each group of low-voltage side impedance units is respectively connected to multiple groups of high-voltage impedance units, and the other end is connected in parallel to the neutral line port N.

[0040] In one embodiment, a load system compatible with a wide input voltage and adjustable current includes: an anti-mistake locking current is provided between a high voltage input switch K2, a low voltage input switch K1, a group switch K4 and a tie switch K3.

[0041] In one embodiment, Figure 1 As shown, an interlocking circuit is provided between the high-voltage input switch K2 and the low-voltage input switch K1 to prohibit the high-voltage input switch K2 and the low-voltage input switch K1 from being closed at the same time; an interlocking circuit is provided between the high-voltage input switch K2 and the grouping switch K4 to prohibit the high-voltage input switch K2 and the grouping switch K4 from being closed at the same time; an interlocking circuit is provided between the high-voltage input switch K2 and the connecting switch K3 to prohibit the high-voltage input switch K2 and the connecting switch K3 from being closed at the same time.

[0042] In one embodiment, Figure 1 As shown, the load system compatible with a wide input voltage and adjustable current includes: an overvoltage protection device, one end of the overvoltage protection device is connected to one side of the tie switch K3, and the other end is connected to the neutral line port N.

[0043] The overvoltage protection device is set to the highest voltage that the load impedance can withstand in the load system compatible with a wide input voltage and adjustable current. Furthermore, in the load system compatible with a wide input voltage and adjustable current, an overcurrent fuse can be configured in the circuit where the tie switch K3 is located to prevent the input power from being directly short-circuited when the high-voltage input switch K2 and the tie switch K3 are closed at the same time due to abnormal reasons.

[0044] In one embodiment, for any group of high-voltage side impedance units, the rated voltage, rated current and rated impedance of the high-voltage side impedance unit and the low-voltage side impedance unit connected to the high-voltage side impedance unit are the same.

[0045] For example Figure 1As shown, the rated voltage, rated current and rated impedance of the high-voltage side impedance unit R11 and the low-voltage side impedance unit R12 connected to the high-voltage side impedance unit R11 are the same.

[0046] In one embodiment, for any group of high-voltage side impedance units and low-voltage side impedance units, the minimum current of the impedance unit is less than or equal to a preset minimum load current, wherein the preset minimum load current is determined based on the minimum input voltage; the sum of the total currents of all impedance units is greater than or equal to a preset maximum load current, wherein the preset maximum load current is determined based on the maximum input voltage.

[0047] In one embodiment, a method for adjusting a load is provided, which is applied to Figure 1 The load system shown is compatible with a wide input voltage and has adjustable current, and the method includes: when the input voltage is lower than a preset voltage, controlling the low-voltage input switch K1, the grouping switch K4 and the connecting switch K3 to close, and the high-voltage input switch K2 to open, so that multiple groups of high-voltage side impedance units are connected in parallel with the low-voltage side impedance units.

[0048] The load system compatible with a wide input voltage and adjustable current can be connected to different power supply devices to be tested. According to the input voltage provided by the power supply device to be tested, the low-voltage input switch K1, the grouping switch K4, the connecting switch K3, the high-voltage input switch K2 and the load throw-in / out switches corresponding to the multiple groups of high-voltage side impedance units and the low-voltage side impedance units are controlled so that the load of the adjustable load system is within the preset value range corresponding to the input voltage, thereby determining the load capacity of the power supply device corresponding to the input voltage.

[0049] For example Figure 2 As shown, when the input voltage provided by the power supply device to be tested is lower than the preset voltage, the low-voltage input switch K1, the grouping switch K4 and the connecting switch K3 can be controlled to close, and the high-voltage input switch K2 can be opened, so that multiple groups of high-voltage side impedance units are connected in parallel with the low-voltage side impedance units.

[0050] In one embodiment, the high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units are controlled respectively so that the load of the adjustable load system is within a preset value range, wherein the preset value range is determined according to the input voltage.

[0051] For example Figure 2As shown, assuming that there are four groups of high-voltage side impedance units and corresponding high-voltage impedance load switches K11, K21, K31, and K41, and four groups of low-voltage side impedance units and corresponding low-voltage impedance load switches K21, K22, K32, and K42, when the input voltage is lower than the preset voltage, all impedance load switches can be controlled to be closed to obtain the operating state of each switch unit when the input voltage is lower and with maximum load.

[0052] In one embodiment, a method for adjusting a load is provided, which is applied to Figure 1 The load system shown is compatible with a wide input voltage and has adjustable current. When the input voltage is higher than a preset voltage, the low-voltage input switch K1, the grouping switch K4 and the connecting switch K3 are controlled to be disconnected, and the high-voltage input switch K2 is closed, so that the high-voltage side impedance unit is connected in series with the low-voltage side impedance unit.

[0053] In one embodiment, the high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units are controlled respectively so that the load of the adjustable load system is within a preset value range, wherein the preset value range is determined according to the input voltage.

[0054] like Figure 3 As shown, when the voltage to be tested is higher than the preset voltage, the low voltage input switch K1, the grouping switch K4 and the tie switch K3 are controlled to be disconnected, and the high voltage input switch K2 is closed, so that the high voltage side impedance unit is connected in series with the low voltage side impedance unit. Assuming that there are four groups of high voltage side impedance units and corresponding high voltage impedance load switches K11, K21, K31, K41, and four groups of low voltage side impedance units and corresponding low voltage impedance load switches K21, K22, K32, K42, when the input voltage is higher than the preset voltage, as shown in FIG. Figure 3 As shown, the high-voltage load switches K21 and K31 can be controlled to be disconnected to obtain the operating state of each switch unit when a higher voltage is input and the load is 50%.

[0055] In one embodiment, Figure 1The load system shown is compatible with a wide input voltage and has adjustable current. This embodiment is described in detail with reference to a load system case that needs to be compatible with two input voltage conditions of 100V and 200V, but the total rated power under the two voltages is 80kW. At this time, the rated resistance, current and voltage parameters of the four low-voltage impedance units are designed to be 2Ω / 50A / 100V, 1Ω / 100A / 100V, 1Ω / 100A / 100V, and 0.67Ω / 150A / 100V respectively; the rated resistance, current and voltage parameters of the corresponding four high-voltage impedance units are also designed to be 2Ω / 50A / 100V, 1Ω / 100A / 100V, 1Ω / 100A / 100V, and 0.67Ω / 150A / 100V respectively. The current carrying capacity of the series-connected load switching switch is designed to be no less than the current carrying capacity of the power-type impedance unit. Considering the typical switch specification parameters, low-voltage molded case circuit breakers with rated currents of 63A, 125A, 125A, and 250A are selected respectively.

[0056] When the input voltage does not exceed 100V, the low-voltage input switch K1, group switch K4 and contact switch K3 are closed, and the high-voltage input switch K2 is closed. At this time, the high-voltage side impedance unit and the low-voltage side impedance unit have a total of 8 load impedances connected in parallel. By controlling the eight circuit breakers K11, K12, K21, K22, K31, K32, K41, and K42 respectively, the load current and power can be controlled. When the input voltage reaches 100V, the corresponding load currents of each circuit breaker are 50A, 50A, 100A, 100A, 100A, 100A, 150A, and 150A, respectively, so that a maximum load of 800A / 80kW can be obtained; when different circuit breaker combinations are put into use, various load currents with a step difference of 50A between 50-800A can be obtained; in such a case Figure 3 In the operation mode shown, a load power of 100V / 800A / 80kW can be obtained. When the input voltage is lower than 100V, the load current of each channel is proportional to the current port voltage, and the load current does not exceed 800A.

[0057] When the input voltage exceeds 100V but is lower than 200V, the low-voltage input switch K1, group switch K4 and contact switch K3 are controlled to be disconnected, and the high-voltage input switch K2 is closed. At this time, the four groups of high-voltage impedance units are connected in series with the corresponding low-voltage impedance units, and the four switches K12, K22, K32 and K42 corresponding to each low-voltage impedance unit are kept normally closed. The load current and power can be controlled by controlling the switches K11, K21, K31 and K41 corresponding to the high-voltage impedance units. When the input is 200V, the load current corresponding to each circuit breaker is 50A, 100A, 100A and 150A respectively, so that the maximum load of 400A / 160kW can be obtained; when different circuit breaker combinations are put into use, various load currents with a step difference of 50A between 50-400A can be obtained. When Figure 3 In the operation mode shown, a load power of 200V / 200A / 40kW can be obtained. When the input voltage is lower than 200V, the load current of each circuit breaker is proportional to the port voltage at that time, and a load current of no more than 400A can be obtained.

[0058] It should be noted that when the input voltage does not exceed 100V, the low-voltage input switch K1 may not be used but the high-voltage input switch K2 may be used for loading. However, in this operation mode, the actual load current will be lower. For example, when the input voltage is 100V, if this operation mode is adopted, the load currents when the corresponding switches K11, K21, K31, and K41 of the high-voltage impedance unit are respectively used are 25A, 50A, 50A, and 75A. Although the current in this mode is smaller, a finer load current can be obtained.

[0059] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware.

[0060] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0061] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A load system compatible with wide input voltage and adjustable current, characterized in that: The load system comprises: A low voltage input switch, wherein the input side of the low voltage input switch is connected to the live wire port; A high voltage input switch, the input side of which is connected in parallel with the input side of the low voltage input switch and connected to the live wire port; A tie switch, one side T of the tie switch is connected to the output side of the high voltage input switch, and the other side is connected to the neutral line port; A plurality of groups of high-voltage side impedance units, each group of high-voltage side impedance units includes an impedance load and a corresponding high-voltage impedance load switch, one end of the plurality of groups of high-voltage side impedance units is connected in parallel to the output side of the high-voltage input switch, and the other end is respectively connected to one end of the plurality of groups of low-voltage side impedance units; A plurality of groups of low-voltage side impedance units, each group of low-voltage side impedance units includes an impedance load and a corresponding low-voltage impedance load switch, one end of the plurality of groups of low-voltage side impedance units is respectively connected to the plurality of groups of high-voltage impedance units, and the other end is connected in parallel to the neutral line port; A grouping switch, one end of which is connected in parallel to the output side of the low-voltage input switch, and the other end is respectively connected to the connection point between each group of high-voltage side impedance units and low-voltage side impedance units.

2. The load system compatible with wide input voltage and adjustable current according to claim 1, characterized in that: The load system comprises: An anti-mistake locking current is provided between the high voltage input switch, the low voltage input switch, the grouping switch and the tie switch.

3. The load system compatible with wide input voltage and adjustable current according to claim 2, characterized in that: An interlock circuit is provided between the high voltage input switch and the low voltage input switch to prohibit the high voltage input switch and the low voltage input switch from being closed at the same time; An interlocking circuit is provided between the high-voltage input switch and the grouping switch to prohibit the high-voltage input switch and the grouping switch from being closed at the same time; An interlocking circuit is provided between the high-voltage input switch and the tie switch to prohibit the high-voltage input switch and the tie switch from being closed at the same time.

4. The load system compatible with wide input voltage and adjustable current according to claim 1, characterized in that: The load system further comprises: An overvoltage protection device, one end of which is connected to one side of the tie switch, and the other end of which is connected to the neutral line port.

5. The load system compatible with wide input voltage and adjustable current according to claim 1, characterized in that: For any group of high-voltage side impedance units, the rated voltage, rated current and rated impedance of the high-voltage side impedance unit and the low-voltage side impedance unit connected to the high-voltage side impedance unit are the same.

6. The load system compatible with wide input voltage and adjustable current according to claim 1, characterized in that: For any group of high-voltage side impedance units and low-voltage side impedance units, the minimum current of the impedance unit is less than or equal to a preset minimum load current, wherein the preset minimum load current is determined according to the minimum input voltage; The sum of the total currents of all impedance units is greater than or equal to a preset maximum load current, wherein the preset maximum load current is determined according to the maximum input voltage.

7. A method for regulating a load, characterized in that: Applied to the load system compatible with wide input voltage and adjustable current as claimed in claim 1, the method comprises: When the input voltage is lower than the preset voltage, the low voltage input switch, the grouping switch and the connecting switch are controlled to be closed, and the high voltage input switch is opened, so that multiple groups of high voltage side impedance units are connected in parallel with the low voltage side impedance units.

8. The method for adjusting a load according to claim 7, characterized in that: The method comprises: The high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units are controlled respectively so that the load of the adjustable load system is within a preset value range, wherein the preset value range is determined according to the input voltage.

9. The method for adjusting a load according to claim 7, characterized in that: The method further comprises: When the input voltage is higher than the preset voltage, the low voltage input switch, the grouping switch and the tie switch are controlled to be disconnected, and the high voltage input switch is closed, so that the high voltage side impedance unit is connected in series with the low voltage side impedance unit.

10. The method for regulating a load according to claim 9, characterized in that: The method further comprises: The high-voltage impedance load switches corresponding to each group of high-voltage side impedance units and the ground voltage impedance load switches corresponding to each group of low-voltage side impedance units are controlled respectively so that the load of the adjustable load system is within a preset value range, wherein the preset value range is determined according to the input voltage.

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