Voltage switching test system

Abstract

The invention relates to a voltage switching test system. The test system comprises a power supply circuit, a control circuit and a power switch driving circuit, the control circuit is connected between the power supply circuit and the power switch driving circuit, and the power switch driving circuit is also used for being connected with equipment to be tested; the power supply circuit is used for supplying power to the control circuit; the control circuit is used for generating a switching test control signal according to the voltage switching instruction; and the power switch driving circuit is used for driving a power switch tube in the power switch driving circuit to be switched on or switched off according to the switching test control signal sent by the control circuit, so that the to-be-tested equipment is switched out or switched into the test system at different voltages. In the switching process, the time spent on voltage rising or falling is smaller than the millisecond level, the requirement for instantaneous change of the voltage of the power grid can be met, and the voltage switching test effect on the to-be-tested equipment is improved.

Description

Technical Field

[0001] This application relates to the field of voltage switching technology, and in particular to a voltage switching test system. Background Technology

[0002] A power grid simulator is an AC power source that can simulate the power grid. For example, it can simulate the power grid supplying power to the device under test, or the power grid absorbing the grid-connected power of the device under test. It can also controllably simulate various power grid anomalies, harmonics, three-phase imbalance, phase loss, and missing phases in actual power grid operation.

[0003] In related technologies, when using a power grid simulator to perform voltage switching tests on the device under test in order to evaluate the grid-connected operation performance of the device under test, the power grid simulator will output a voltage waveform that rises or falls instantaneously within its own voltage switching maximum slope. However, the voltage rise or fall time is only at the millisecond level at the fastest, which is difficult to meet the requirements of instantaneous changes in grid voltage, resulting in poor voltage switching test effect for the device under test. Summary of the Invention

[0004] Therefore, it is necessary to provide a new voltage switching test system that can improve the voltage switching test effect of the device under test.

[0005] This application provides a voltage switching test system, which includes a power supply circuit, a control circuit, and a power switch drive circuit; the control circuit is connected between the power supply circuit and the power switch drive circuit, and the power switch drive circuit is also used to connect to the device under test.

[0006] The power supply circuit is used to supply power to the control circuit;

[0007] The control circuit is used to generate a switching test control signal according to the voltage switching command;

[0008] The power switch driving circuit is used to drive the power switch in the power switch driving circuit to turn on or off according to the switching test control signal sent by the control circuit, so that the device under test can be switched off or connected to the test system with different voltages.

[0009] In one embodiment, the power switch driving circuit includes a first power switch module and a second power switch module; the input terminals of the first power switch module and the second power switch module are respectively connected to AC voltage and DC voltage, and the output terminals of the first power switch module and the second power switch module are both used to connect to the device under test.

[0010] In one embodiment, the power switch driving circuit further includes a switching transistor driving circuit; the switching transistor driving circuit is connected to both the first power switch module and the second power switch module.

[0011] The switching transistor driving circuit is used to drive the first power switching transistor module to turn off and the second power switching transistor module to turn off according to the switching test control signal, so that the device under test (DUT) switches out of the test system; or drive the first power switching transistor module to turn off and the second power switching transistor module to turn on, so that the DUT is connected to the test system with DC voltage; or drive the first power switching transistor module to turn on and the second power switching transistor module to turn off, so that the DUT is connected to the test system with AC voltage.

[0012] In one embodiment, the switching transistor driving circuit is further configured to drive the first power switching transistor module to remain on during a first time period, the first power switching transistor module to remain off during a second time period, the second power switching transistor module to remain on during a third time period, and the second power switching transistor module to remain off during a fourth time period.

[0013] The third time period does not overlap with the first time period on the time axis, while the fourth time period partially overlaps with the second time period on the time axis.

[0014] In one embodiment, during the process of the device under test switching from being connected to the test system with DC voltage to being connected to the test system with AC voltage, the switching transistor drive circuit is further configured to drive the second power switching transistor module to turn off after a preset delay period before driving the first power switching transistor module to turn on.

[0015] In one embodiment, the control circuit is further configured to configure a first time period, a second time period, a third time period, and a fourth time period that match the time period switching instruction, according to the time period switching instruction carrying the target time period switching instruction.

[0016] In one embodiment, the first power switch module and / or the second power switch module include at least one power switch.

[0017] Alternatively, the first power switch module and / or the second power switch module may include at least two power switches, and the at least two power switches may be connected in series sequentially.

[0018] In one embodiment, the power switch includes an insulated gate bipolar transistor.

[0019] In one embodiment, the power switch drive circuit further includes an AC source circuit and a DC source circuit; the AC source circuit and the DC source circuit are respectively connected to the device under test (DUT) through corresponding power switches; the AC source circuit is used to provide AC voltage to the DUT through the corresponding power switch during a first time period when the DUT is put into the test system, and the DC source circuit is used to provide DC voltage to the DUT through the corresponding power switch during a third time period when the DUT is put into the test system.

[0020] The third time period does not overlap with the first time period on the time axis.

[0021] In one embodiment, the power switch drive circuit further includes a first switch, and the AC source circuit is connected to the corresponding power switch transistor through the first switch.

[0022] In one embodiment, the AC source circuit includes a power grid simulator; the AC voltage output terminal of the power grid simulator is connected to the device under test through a corresponding power switch, and the switching trigger terminal of the power grid simulator is connected to the control circuit.

[0023] The power grid simulator is used to output a trigger signal to the control circuit through the switching trigger terminal according to the voltage switching command carrying the target switching phase, so that the control circuit generates a switching test control signal according to the trigger signal.

[0024] In one embodiment, the power switch drive circuit further includes a second switch; the second switch is connected between the AC power source circuit and the device under test.

[0025] The aforementioned voltage switching test system includes a power supply circuit, a control circuit, and a power switch drive circuit connected in sequence. The power supply circuit supplies power to the control circuit, which generates a switching test control signal based on a voltage switching command. The power switch drive circuit is also connected to the device under test (DUT). Based on the switching test control signal sent by the control circuit, the power switch drive circuit drives the power switch transistor in the power switch drive circuit to turn on or off, thereby allowing the DUT to switch out of or into the voltage switching test system at different voltages, thus achieving voltage switching testing of the DUT. In this embodiment, because the voltage switching test system achieves voltage switching testing of the DUT by driving the power switch transistor to turn on or off, the switching speed of the power switch transistor is very fast. During the switching process, the time taken for the voltage to rise or fall is less than milliseconds, thus meeting the requirements of instantaneous changes in grid voltage, thereby improving the voltage switching test effect of the DUT. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a voltage switching test system according to one embodiment;

[0028] Figure 2 This is one of the connection diagrams of a power switch drive circuit according to an embodiment;

[0029] Figure 3 This is a second connection diagram of a power switch drive circuit according to an embodiment;

[0030] Figure 4 This is the third connection diagram of a power switch drive circuit according to an embodiment;

[0031] Figure 5 Fourthly, a connection diagram of a power switch drive circuit according to an embodiment;

[0032] Figure 6 Fifth of the connection diagrams for a power switch drive circuit according to an embodiment;

[0033] Figure 7 This is a sixth connection diagram of a power switch drive circuit according to an embodiment;

[0034] Figure 8 This is a timing diagram of a voltage switching test system according to one embodiment.

[0035] Explanation of reference numerals in the attached figures:

[0036] 100 - Voltage switching test system, 110 - Power supply circuit, 120 - Control circuit, 130 - Power switch drive circuit, 131 - First power switch module, 132 - Second power switch module, 133 - Switch drive circuit, 134 - AC source circuit, 135 - DC source circuit, 136 - First switch, 137 - Second switch. Detailed Implementation

[0037] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be more thorough and complete.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0039] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0040] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0041] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0042] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0043] The voltage switching test system provided in this application can be applied to, but is not limited to, devices to be connected to the power grid. Before the device is connected to the power grid, the voltage switching test system can be used to conduct voltage switching tests on it to simulate the connection to the power grid, ensuring that it is ultimately connected to the power grid with good grid adaptability and can adapt and operate well under the real-world conditions of instantaneous changes in grid voltage.

[0044] In one exemplary embodiment, reference is made to Figure 1 A voltage switching test system is provided. The test system 100 includes a power supply circuit 110, a control circuit 120, and a power switch drive circuit 130.

[0045] The control circuit 120 is connected between the power supply circuit 110 and the power switch drive circuit 130. The power supply circuit 110 is used to supply power to the control circuit 120. The control circuit 120 is used to generate a switching test control signal according to the voltage switching command. The power switch drive circuit 130 is also used to connect to the device under test 200.

[0046] The power supply circuit 110 provides the voltage required for normal operation to the control circuit 120. The power supply circuit 110 may have at least a voltage conversion function. For example, the power supply circuit 110 can convert 220V AC mains power to AC / DC (i.e., AC to DC power) and output 24V DC power to power the control circuit 120.

[0047] For example, the control circuit 120 may include a control board; the control board is provided with voltage input pins Vin+ and Vin- for receiving the power supply voltage provided by the power supply circuit 110; and the control board is provided with GPIO (general purpose input / output) pins, which can receive signals such as voltage switching commands, switching time period commands, and trigger signals, as well as output switching test control signals.

[0048] When the device under test 200 is connected to the voltage switching test system 100 and a voltage switching test is required, the voltage switching test system 100 can receive a voltage switching command, which may be issued by, but is not limited to, a user. The control circuit 120 can generate a switching test control signal according to the voltage switching command to control the power switch drive circuit 130.

[0049] The power switch drive circuit 130 can drive the power switch tube in the power switch drive circuit 130 to turn on or off according to the switching test control signal sent by the control circuit 120, so that the device under test 200 can be switched out or connected to the voltage switching test system 100 with different voltages, thereby realizing the voltage switching test of the device under test 200.

[0050] For example, the power switch drive circuit 130 may include power switching transistors and a drive circuit for driving the power switching transistors. According to the switching test control signal sent by the control circuit 120, the drive circuit drives a portion of the relevant power switching transistors in the power switch drive circuit 130 to turn on, so that the device under test 200 is connected to the voltage switching test system 100 with a first voltage. After maintaining the first voltage for a period of time, it can also drive all the relevant power switching transistors in the power switch drive circuit 130 to turn off, so that the device under test 200 is disconnected from the voltage switching test system 100, that is, the voltage supplied to the device under test 200 drops from the first voltage to zero. After maintaining the voltage at zero for a period of time, it can also drive another portion of the relevant power switching transistors in the power switch drive circuit 130 to turn on, so that the device under test 200 is connected to the voltage switching test system 100 with a second voltage. Similarly, the second voltage can be maintained for a period of time, that is, the voltage supplied to the device under test 200 rises from zero to the second voltage. This realizes that the device under test 200 can be disconnected or connected to the voltage switching test system 100 with different voltages.

[0051] In this embodiment, the voltage switching test system 100 performs voltage switching tests on the device under test 200 by driving the power switching transistor to turn on or off. The power switching transistor has a very fast switching speed, and the time taken for the voltage to rise (e.g., rise from zero to a second voltage) or fall (e.g., fall from the first voltage to zero) during the switching process is less than milliseconds. This allows the system to meet the requirements of instantaneous changes in grid voltage, thereby improving the voltage switching test effect on the device under test 200.

[0052] In this application embodiment, the power switch driving circuit 130 may have various specific structures. Only a few of them are described below as examples, but they are not intended to limit the power switch driving circuit 130.

[0053] In one exemplary embodiment, reference is made to Figure 2 The power switch drive circuit 130 includes a first power switch module 131 and a second power switch module 132. The input terminals of the first power switch module 131 and the second power switch module 132 are respectively connected to AC voltage and DC voltage. The output terminals of the first power switch module 131 and the second power switch module 132 are both used to connect to the device under test 200.

[0054] In this embodiment, the power switch driving circuit 130 can drive the first power switch module 131 and the second power switch module 132 to turn on or off, so that the device under test 200 can be switched off or connected to the voltage switching test system 100 with AC or DC voltage, thereby realizing the voltage switching test of the device under test 200.

[0055] In one exemplary embodiment, reference is made to Figure 3 The power switch drive circuit 130 also includes a switch transistor drive circuit 133. The switch transistor drive circuit 133 is connected to both the first power switch transistor module 131 and the second power switch transistor module 132.

[0056] The switching transistor drive circuit 133 is used to drive the first power switching transistor module 131 to turn off and the second power switching transistor module 132 to turn off according to the switching test control signal, so that the device under test 200 switches out of the voltage switching test system 100; or drive the first power switching transistor module 131 to turn off and the second power switching transistor module 132 to turn on, so that the device under test 200 is connected to the voltage switching test system 100 with DC voltage; or drive the first power switching transistor module 131 to turn on and the second power switching transistor module 132 to turn off, so that the device under test 200 is connected to the voltage switching test system 100 with AC voltage.

[0057] For example, the switching transistor driving circuit 133 may include a driving board, on which a driving chip is provided. The driving chip can drive the first power switching transistor module 131 and the second power switching transistor module 132 according to the switching test control signal.

[0058] In this embodiment, the switching transistor drive circuit 133, the first power switching transistor module 131, and the second power switching transistor module 132 can be integrated on the same circuit board. The switching transistor drive circuit 133 serves as the drive circuit for the first power switching transistor module 131 and the second power switching transistor module 132. The control circuit 120 can also be understood as the control circuit 120 of the switching transistor drive circuit 133. Thus, for example, program code related to voltage switching test is written in the control circuit 120. When the device under test 200 is connected to the voltage switching test system 100 and a voltage switching test is required, the control circuit 120 generates a switching test control signal according to the voltage switching command. The switching transistor drive circuit 133 drives the first power switching transistor module 131 and the second power switching transistor module 132 to turn on or off according to the switching test control signal, so that the device under test 200 is switched out or connected to the voltage switching test system 100 with AC or DC voltage, thereby realizing the voltage switching test of the device under test 200.

[0059] In an exemplary embodiment, the switching transistor driving circuit 133 is further configured to drive the first power switching transistor module 131 to remain on during a first time period, thereby continuously providing AC voltage to the device under test 200 during the first time period, i.e., providing AC voltage to the device under test 200 to maintain the first time period; the switching transistor driving circuit 133 is further configured to drive the first power switching transistor module 131 to remain off during a second time period, thereby continuously not providing AC voltage to the device under test 200 during the second time period, i.e., stopping the provision of AC voltage to the device under test 200 to maintain the second time period; the switching transistor driving circuit 133 is further configured to drive the second power switching transistor module 132 to remain on during a third time period, thereby providing DC voltage to the device under test 200 to maintain the third time period; the switching transistor driving circuit 133 is further configured to drive the second power switching transistor module 132 to remain off during a fourth time period, thereby stopping the provision of DC voltage to the device under test 200 to maintain the fourth time period.

[0060] The third time period does not overlap with the first time period on the time axis, thus ensuring that the second power switch module 132 is off when AC voltage is supplied to the device under test 200 through the first power switch module 131, and ensuring that the first power switch module 131 is off when DC voltage is supplied to the device under test 200 through the second power switch module 132. The fourth time period partially overlaps with the second time period on the time axis, thus ensuring that by simultaneously turning off the first power switch module 131 and the second power switch module 132, the voltage supplied to the device under test 200 is zero, and the device under test 200 switches out of the voltage switching test system 100.

[0061] The first, second, third, and / or fourth time periods can be a single, continuous duration or a series of sub-durations; no specific limitations are imposed on this.

[0062] In an exemplary embodiment, during the process of the device under test 200 switching from DC voltage to AC voltage in the voltage switching test system 100, the switching transistor drive circuit 133 is further configured to drive the second power switching transistor module 132 to turn off after a first preset delay period before driving the first power switching transistor module 131 to turn on. Also, during the process of the device under test 200 switching from AC voltage to DC voltage in the voltage switching test system 100, the switching transistor drive circuit 133 is further configured to drive the first power switching transistor module 131 to turn off after a second preset delay period before driving the second power switching transistor module 132 to turn on.

[0063] In this embodiment, considering the turn-on and turn-off delay times of the first power switch module 131 and the second power switch module 132, in order to avoid the first power switch module 131 and the second power switch module 132 being turned on simultaneously, that is, to avoid simultaneously providing AC voltage and DC voltage to the device under test 200, the switch drive circuit 133 is also used to drive the second power switch module 132 to turn off after a first preset delay period during the process of switching from DC voltage to AC voltage, and similarly, during the process of switching from AC voltage to DC voltage, the switch drive circuit 133 is also used to drive the first power switch module 131 to turn off after a second preset delay period during the process of switching from AC voltage to DC voltage, and then drive the second power switch module 132 to turn on.

[0064] In an exemplary embodiment, the control circuit 120 is further configured to configure the specific sizes of the first time period, the second time period, the third time period, and the fourth time period that match the time period switching instruction, according to the time period switching instruction carrying the target time period switching instruction.

[0065] In this embodiment, when it is necessary to configure the specific sizes of the first, second, third, and fourth time periods, the voltage switching test system 100 can receive a switching time period command carrying the target switching time period. This command can be, for example, but not limited to, issued by the user. The control circuit 120 can configure the specific sizes of the first, second, third, and fourth time periods matching the switching time period command. After configuration, the voltage switching test can be performed on the device under test 200 according to the configured sizes of the first, second, third, and fourth time periods. That is, in this embodiment, the specific sizes of the first, second, third, and fourth time periods can be flexibly adjusted according to the user's actual needs; they are not fixed and unchangeable.

[0066] In one exemplary embodiment, the first power switch module 131 and / or the second power switch module 132 includes at least one power switch. Alternatively, the first power switch module 131 and / or the second power switch module 132 includes at least two power switches, and the at least two power switches are connected in series sequentially.

[0067] refer to Figure 4 , Figure 4 The example diagram illustrates that both the first power switch module 131 and the second power switch module 132 include two power switches (i.e., Q1~Q4), and the two power switches are connected in series in sequence.

[0068] In this embodiment, the number of power switches in the power switch module and their interconnections are not specifically limited; they can be selected and configured according to actual needs. For example... Figure 4 In the first power switch module 131 and the second power switch module 132, there are two power switches each, and the two power switches are connected in series. This not only reliably meets the high requirements for switching speed, but also has low cost.

[0069] In the embodiments of this application, the power switching transistors are, for example, IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), thyristors, etc.

[0070] In one exemplary embodiment, the power switch includes an insulated gate bipolar transistor.

[0071] In this embodiment, the voltage switching test system 100 performs voltage switching tests on the device under test 200 by driving the insulated gate bipolar transistor (IGBT) to turn on or off. The IGBT has a very fast switching speed, and the time taken for the voltage to rise or fall during the switching process is extremely short, at most at the microsecond level. This meets the requirements of instantaneous changes in grid voltage, thereby improving the voltage switching test effect of the device under test 200.

[0072] In one exemplary embodiment, reference is made to Figure 5 The power switch drive circuit 130 also includes an AC source circuit 134 and a DC source circuit 135. The AC source circuit 134 and the DC source circuit 135 are respectively connected to the device under test 200 through corresponding power switches. The AC source circuit 134 is used to provide AC voltage to the device under test 200 through the corresponding power switch during the first time period when the voltage switching test system 100 is connected to the device under test 200. The DC source circuit 135 is used to provide DC voltage to the device under test 200 through the corresponding power switch during the third time period when the voltage switching test system 100 is connected to the device under test 200. The third time period does not overlap with the first time period on the time axis.

[0073] In this embodiment, the AC power supply circuit 110 external to the voltage switching test system 100 may provide AC voltage to the first power switch module 131, and the DC power supply circuit 110 externally may provide DC voltage to the second power switch module 132. Alternatively, the AC source circuit 134 and the DC source circuit 135 provided in the power switch drive circuit 130 may provide AC and DC voltages to the first power switch module 131 and the second power switch module 132, respectively.

[0074] In an exemplary embodiment, the AC source circuit 134 in the power switch drive circuit 130 is a power grid simulator. The AC voltage output terminal of the power grid simulator is connected to the device under test 200 through a corresponding power switch transistor, and the switching trigger terminal of the power grid simulator is connected to the control circuit 120. The power grid simulator is used to output a trigger signal to the control circuit 120 through the switching trigger terminal according to the voltage switching command carrying the target switching phase, so that the control circuit 120 generates a switching test control signal according to the trigger signal.

[0075] In this embodiment, an AC voltage, such as 220V AC mains voltage, can be provided to the first power switch module 131 through a power grid simulator; while the voltage switching of the device under test 200 is achieved by the first power switch module 131 and the second power switch module 132, thereby increasing the speed of voltage rise and fall.

[0076] In addition, when using a power grid simulator to provide AC voltage, the power grid simulator can also receive voltage switching commands. Based on the target switching phase information in the voltage switching command, the power grid simulator outputs a trigger signal to the control circuit 120 at the target switching phase via a switching trigger terminal. This causes the control circuit 120 to generate a switching test control signal based on the trigger signal, thus initiating the voltage switching test on the device under test 200. The target switching phase can be, for example, 0°, 90°, 180°, or 270°.

[0077] In one exemplary embodiment, reference is made to Figure 6 The power switch drive circuit 130 also includes a first switch 136. The AC power source circuit 134 is connected to the corresponding power switch transistor via the first switch 136. The first switch 136 is used to control the connection and disconnection between the AC power source circuit 134 and the first power switch transistor module 131.

[0078] In one exemplary embodiment, reference is made to Figure 7 The power switch drive circuit 130 also includes a second switch 137. The second switch 137 is connected between the AC power source circuit 134 and the device under test 200. For example, a power grid simulator can be directly connected to the device under test 200 via the second switch. When a voltage switching test is required, the second switch 137 can be opened; when a voltage switching test is not required, the second switch 137 can be closed, allowing the power grid simulator to directly connect to the device under test 200 and simulate other power grid scenarios for the device under test 200.

[0079] In one exemplary embodiment, the power switch drive circuit 130 further includes a terminal block. The first power switch module 131 and the second power switch module 132 are connected to the device under test 200 via the terminal block. For example, the power switch drive circuit 130 may be packaged with only the terminal block exposed, so that the external device under test 200 can be connected to the first power switch module 131 and the second power switch module 132 inside the power switch drive circuit 130 via the exposed terminal block.

[0080] The following is combined Figure 7 and Figure 8 The voltage switching test system 100 provided in the embodiments of this application will be further illustrated by the following examples:

[0081] If voltage switching testing is not required, disconnect the first switch 136 and close the second switch 137.

[0082] When a voltage switching test is required, the first switch 136 is closed and the second switch 137 is opened. First, both IGBTs (Q1 and Q2) in the first power switching module 131 are turned on, and both IGBTs (Q3 and Q4) in the second power switching module 132 are turned off. The grid simulator supplies AC 220V to the device under test 200 through the closed first switch 136 and the turned-on Q1 and Q2. Then, at the target switching phase, a voltage switching command is sent to the grid simulator. The grid simulator outputs a trigger signal to the control circuit 120 through the switching trigger terminal according to the voltage switching command. The control circuit 120 generates a switching test control signal based on the trigger signal and begins the voltage switching test of the device under test 200.

[0083] Within time T1, Q1, Q2, Q3, and Q4 are all turned off, causing the voltage supplied to the device under test (DUT) 200 to drop from AC 220V to zero, and this zero voltage is maintained for the duration of T1. Within time T2, Q1 and Q2 remain off, while Q3 and Q4 are turned on, causing the voltage supplied to the DUT 200 to rise from zero to DC 404V (1.3 times the AC voltage amplitude), and this 404V voltage is maintained for the duration of T2. After a delay following T2, Q3 and Q4 remain off, while Q1 and Q2 are turned on, causing the voltage supplied to the DUT 200 to switch from DC 404V to AC 220V. This completes one voltage switching test of the DUT 200. Before each voltage switching test, the user can flexibly configure the specific values ​​of T1 and T2 as needed, and the magnitudes of both the DC and AC voltages can be flexibly configured as required.

[0084] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0085] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A voltage switching test system, characterized in that, It includes a power supply circuit, a control circuit, and a power switch drive circuit; the control circuit is connected between the power supply circuit and the power switch drive circuit, and the power switch drive circuit is also used to connect to the device under test. The power supply circuit is used to supply power to the control circuit; The control circuit is used to generate a switching test control signal according to the voltage switching command; The power switch driving circuit is used to drive the power switch in the power switch driving circuit to turn on or off according to the switching test control signal sent by the control circuit, so that the device under test can be switched off or connected to the test system with different voltages.

2. The voltage switching test system according to claim 1, characterized in that, The power switch drive circuit includes a first power switch module and a second power switch module; the input terminals of the first power switch module and the second power switch module are respectively connected to AC voltage and DC voltage, and the output terminals of the first power switch module and the second power switch module are both used to connect to the device under test.

3. The voltage switching test system according to claim 2, characterized in that, The power switch driving circuit further includes a switching transistor driving circuit; the switching transistor driving circuit is connected to both the first power switch module and the second power switch module. The switching transistor driving circuit is used to drive the first power switching transistor module to turn off and the second power switching transistor module to turn off according to the switching test control signal, so that the device under test (DUT) switches out of the test system; or drive the first power switching transistor module to turn off and the second power switching transistor module to turn on, so that the DUT is connected to the test system with DC voltage; or drive the first power switching transistor module to turn on and the second power switching transistor module to turn off, so that the DUT is connected to the test system with AC voltage.

4. The voltage switching test system according to claim 3, characterized in that, The switching transistor driving circuit is also used to drive the first power switching transistor module to remain on during a first time period, the first power switching transistor module to remain off during a second time period, the second power switching transistor module to remain on during a third time period, and the second power switching transistor module to remain off during a fourth time period. The third time period does not overlap with the first time period on the time axis, while the fourth time period partially overlaps with the second time period on the time axis.

5. The voltage switching test system according to claim 4, characterized in that, During the process of the device under test switching from DC voltage to AC voltage in the test system, the switching transistor drive circuit drives the first power switching transistor module to turn on after a preset delay period of driving the second power switching transistor module to turn off.

6. The voltage switching test system according to claim 4 or 5, characterized in that, The control circuit is also configured to configure the first time period, the second time period, the third time period, and the fourth time period that match the time period switching instruction according to the time period switching instruction carrying the target time period switching instruction.

7. The voltage switching test system according to any one of claims 2-5, characterized in that, The first power switch module and / or the second power switch module include at least one power switch. Alternatively, the first power switch module and / or the second power switch module may include at least two power switches, and the at least two power switches may be connected in series sequentially.

8. The voltage switching test system according to any one of claims 1-5, characterized in that, The power switch drive circuit further includes an AC source circuit and a DC source circuit; the AC source circuit and the DC source circuit are respectively connected to the device under test (DUT) through corresponding power switching transistors; the AC source circuit is used to provide AC voltage to the DUT through the corresponding power switching transistor during the first time period when the DUT is put into the test system, and the DC source circuit is used to provide DC voltage to the DUT through the corresponding power switching transistor during the third time period when the DUT is put into the test system. The third time period does not overlap with the first time period on the time axis.

9. The voltage switching test system according to claim 8, characterized in that, The power switch drive circuit also includes a first switch, and the AC source circuit is connected to the corresponding power switch tube through the first switch.

10. The voltage switching test system according to claim 9, characterized in that, The AC source circuit includes a power grid simulator; the AC voltage output terminal of the power grid simulator is connected to the device under test through a corresponding power switch, and the switching trigger terminal of the power grid simulator is connected to the control circuit. The power grid simulator is used to output a trigger signal to the control circuit through the switching trigger terminal according to the voltage switching command carrying the target switching phase, so that the control circuit generates a switching test control signal according to the trigger signal.

11. The voltage switching test system according to claim 9 or 10, characterized in that, The power switch drive circuit further includes a second switch; the second switch is connected between the AC power source circuit and the device under test.

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