Load testing equipment and systems

Abstract

The present invention provides a load testing device and system, wherein the load testing device includes: a product to be tested, a controller module, a load module, a switch module and a data monitoring module; the load module includes an impact resistance module, a steady-state resistance module and an inductance module; the product to be tested, the inductance module, the impact resistance module and the steady-state resistance module are connected in sequence; the controller module is connected to the switch module; the steady-state resistance module and the impact resistance module each include multiple resistors, the inductance module includes multiple inductors, the switch module includes multiple relays or electronic switches, each resistor is connected in parallel with a relay or an electronic switch; each inductor is connected in parallel with a relay or an electronic switch. The present application controls the opening or closing of the switch module through the controller module, and uses different combinations of enabling or disabling the relay or the electronic switch to control the working state of the corresponding resistor and inductor, obtains different reactance values, and provides a high-quality load for the test.

Description

Technical Field

[0001] The present invention relates to the technical field of product testing, and in particular to a load testing device and system. Background Art

[0002] At present, the commonly used loads on the market include DC electronic loads, AC electronic loads, fixed resistors, and sliding resistors. Among them, electronic loads are devices that consume electrical energy by controlling the conduction of internal power components such as Mosfet or transistors and relying on the dissipated power of power tubes. During the working process, various electrical signals of the circuit must be continuously detected and corresponding control signals must be made. There is a certain hysteresis time, and the voltage / current signals cannot be fully synchronized. In addition, the harmonics and spikes generated by the high-frequency switching electronic load during discharge have a certain impact on the power devices Mosfet or transistors of the electronic switch, and in severe cases, they may even be broken down and burned.

[0003] During use, the following problems were found in the load:

[0004] 1. DC electronic load: 1. Some of the company's power tools to be tested are connected to DC electronic loads, and the waveform is detected using an oscilloscope. The products to be tested cannot work properly, but they can work properly when ordinary resistance loads or motors are used instead. 2. Use a DC electronic load to test the speed regulation function of the product to be tested, observe the PWM (Pulse Width Modulation) waveform with adjustable switch output duty cycle, and find that the waveform is distorted on the rising / falling edges. 3. Use a DC electronic load to test the speed regulation function of the product to be tested, monitor the PWM (Pulse Width Modulation) waveform with adjustable switch output duty cycle, and find that the waveform is distorted on the rising / falling edges. The larger the load current, the more serious the waveform distortion. This situation causes the field effect tube or transistor inside the product to be tested and other power components to work in the linear amplification area at the edge part, causing the components to heat up, resulting in accelerated temperature rise of the product to be tested, and severe temperature rise will be too high, which cannot pass the safety requirements of power tools. 4. Some products to be tested need to pass the impact test of large current narrow pulse (such as 10uS@410A). The electronic load cannot respond to this requirement in time, and the voltage and current cannot be particularly steep on the rising / falling edge. The distortion on the rising / falling edge is particularly serious. The load waveform that was originally a square wave has become similar to or close to a sawtooth wave. The current is only 300A within 10uS, and it does not rise to the test requirement of 410A. Changing the electronic load to an ordinary high-power resistor solves the problem and meets the test requirements.

[0005] 2. AC electronic load: 1. Connect a product to be tested in series with the AC electronic load and connect it to the mains. Use an oscilloscope to measure the voltage / current waveform at both ends of the AC electronic load. It can be found that the waveform has different degrees of distortion near the zero point. 2. When testing the control board of the AC power tool, the thyristor needs to be turned on by the trigger signal after the voltage passes through the zero point. The delay time of the trigger signal after the zero point is closely related to the output conduction angle of the control circuit. The shorter the delay time, the larger the conduction angle, that is, the larger the output voltage. When the trigger signal is rarely delayed after the zero point, the conduction angle waveform of the thyristor is close to a sine wave. Since the AC electronic load consumes electrical energy for the internal energy-consuming device after rectification. The conduction of the rectifier device requires a certain voltage (a single-element silicon tube voltage drop of 0.7v / germanium tube voltage drop of 0.2v), plus the hysteresis of the control circuit, this parameter becomes larger. Then there is such a situation: if the thyristor of the power tool product to be tested is turned on before the control device of the AC electronic load, it becomes a test of the power device of the AC electronic load, rather than a test of the thyristor circuit of the product to be tested, which deviates from the test requirements and cannot reflect the switch performance of the product to be tested. Therefore, the switch with a conduction angle close to full on cannot be tested using an AC electronic load to test its switch function.

[0006] 3. Fixed resistors, the resistance value is fixed and cannot be adjusted, and there is temperature drift. The higher the temperature, the more serious the resistance drift, which affects the functional test of the product.

[0007] 4. Sliding resistors: When sliding, the sliding part is not in close contact with the resistor body, the resistance value jumps, and the precision is low. When the belt is working, the sliding part moves, and the contact point sparks. The larger the current, the more obvious the sparking phenomenon. During use, the resistance value cannot be automatically adjusted according to the set conditions. In addition, the temperature drift is the same as that of fixed resistors.

[0008] The electric tool products to be tested use AC / DC electronic loads, which may produce oscillations during high-frequency pulse operation, resulting in voltage and current spikes, which will affect the temperature rise of the power device field effect tube or transistor and related circuit parts of the product circuit to be tested, and even break down and burn them in serious cases. Fixed resistors and sliding resistors cannot automatically adjust the current changes caused by temperature rise changes, and cannot meet the test requirements. In the production of electric tool products to be tested, especially in the R&D stage, in order to eliminate external influences such as power supply, load, and measuring tools, various functions are strictly tested to obtain accurate parameters.

[0009] Based on this, the present application proposes a device and system for product function testing of a reliability testing machine suitable for a power tool product load to be tested. Summary of the invention

[0010] In view of this, an object of the present invention is to provide a load testing device and system, which enables or disables corresponding resistances and inductors through different combinations of relays or electronic switches to obtain different reactance values, and automatically adjusts the reactance changes according to the test conditions to provide high-quality loads for the test.

[0011] In the first aspect, an embodiment of the present invention provides a load testing device, comprising: a product to be tested, a controller module, a load module, a switch module and a data monitoring module; the load module comprises a surge resistance module, a steady-state resistance module and an inductance module; the product to be tested, the inductance module, the surge resistance module and the steady-state resistance module are connected in sequence, and the controller module is connected to the switch module; the steady-state resistance module and the surge resistance module each comprise a plurality of resistors, the inductance module comprises a plurality of inductors, the switch module comprises a plurality of relays or electronic switches, each resistor is connected in parallel with a relay or an electronic switch; each inductor is connected in parallel with a relay or an electronic switch; each resistor is connected in series with each inductor; the controller module is communicatively connected with the switch module; the data monitoring module is connected with the product to be tested; the controller module is used to send a control instruction to the switch module; the switch module is used to start or close the relay or the electronic switch according to the control instruction; the data monitoring module is used to monitor the test data of the product to be tested, and the test data comprises at least one of the following: power information, voltage information, current information, frequency information and power factor of the product to be tested.

[0012] In a preferred embodiment of the present invention, the load testing device also includes a touch screen, which is used for human-computer interaction and displays combination information, wherein the combination information is the combination information of the inductance module, the impact resistance module and the steady-state resistance module; the controller module is also used to generate control instructions based on the combination information.

[0013] In a preferred embodiment of the present invention, the load testing device further includes a communication module, and the communication module is used to provide a network environment for the load testing device.

[0014] In a preferred embodiment of the present invention, the steady-state resistance module includes a plurality of resistors connected in series, and the resistance values ​​of the resistors included in the steady-state resistance module are customized according to the binary weight law: in ohms, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, 12.8... are selected; starting from 0.1Ω and 2 n When selecting resistors (n is an integer), the resistors can be matched to obtain a precision change of 0.1Ω, and the resistance range is 0 to 2 n The resistance value is Ω (can be increased or decreased as needed).

[0015] In a preferred embodiment of the present invention, the impact resistance module includes a plurality of resistors connected in series. The resistance values ​​of the resistors included in the impact resistance module are customized according to the binary weight law: in ohms, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, 12.8... are selected; starting from 0.1Ω and 2 m When selecting resistors (m is an integer), the resistors can be matched to obtain a precision change of 0.1Ω, and the resistance range is 0~2 m The resistance value is Ω (can be increased or decreased as needed).

[0016] In a preferred embodiment of the present invention, the inductor module includes a plurality of inductors connected in series, and the inductance values ​​of the inductors included in the inductor module are customized according to the binary weight law to customize the inductance of special resistance values: in mH as a unit, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, 12.8... are selected; starting from 0.1mH and increasing by 2 k When selecting inductors (k is an integer), the precision of the pairing can be changed to 0.1mH, and the resistance range is 0 to 2 k mH inductance value (can be increased or decreased as needed).

[0017] In a preferred embodiment of the present invention, the load testing device further comprises an interface module, which comprises: an RS232 interface, an RS422 interface and an RS485 interface, and the interface module is used to provide an RS232 interface, an RS422 interface and an RS485 interface for an external device.

[0018] In a preferred embodiment of the present invention, the controller module is also used to control the switch module according to the test data. When the interface module is connected to the external device, the external device can turn off the adjustment function of the controller module. The adjustment function is the function of the controller module controlling the switch module according to the test data.

[0019] In a second aspect, an embodiment of the present invention further provides a load testing system, comprising: a cloud server and the above-mentioned load testing device, the cloud server and the load testing device being communicatively connected; the load testing device being used to send test data to the cloud server; and the cloud server being used to receive test data.

[0020] In a preferred embodiment of the present invention, the load testing system also includes a terminal device, which is communicatively connected to the cloud server; the terminal device is used to obtain test data from the cloud server.

[0021] The embodiments of the present invention bring the following beneficial effects:

[0022] The present invention provides a load testing device and system, wherein the load testing device comprises: a product to be tested, a controller module, a load module, a switch module and a data monitoring module; the load module comprises an impact resistance module, a steady-state resistance module and an inductance module; the product to be tested, the inductance module, the impact resistance module and the steady-state resistance module are connected in sequence, and the controller module is connected to the switch module; the steady-state resistance module and the impact resistance module each comprise a plurality of resistors, the inductance module comprises a plurality of inductors, the switch module comprises a plurality of relays or electronic switches, each resistor is connected in parallel with a relay or an electronic switch; each inductor is connected in parallel with a relay or an electronic switch; each resistor is connected in series with each inductor; the controller module is communicatively connected with the relay or the electronic switch module; the data monitoring module is connected with the controller module and the product to be tested; the controller module is used for sending a control instruction to the switch module according to the data feedback from the data monitoring module; the switch module is used for executing a start-up or shutdown action according to the control instruction; the data monitoring module is used for monitoring the test data of the product to be tested, and the test data comprises at least one of the following: power information, voltage information, current information, frequency information and power factor of the product to be tested and the temperature rise of the key points of the product. This application controls the opening or closing of the switch module through the controller module, and uses different combinations of enabling or disabling relays or electronic switches to control the working state of the corresponding resistors and inductors, obtain different reactance values, provide high-quality loads for testing, and monitor the test data of the product under test through the data detection module, which can be applied to test scenarios with power factor requirements. The combined pure resistive and resistive plus inductive loads can adapt to the load test of the product under test of DC or AC powered electric tools.

[0023] Other features and advantages of the present disclosure will be set forth in the following description, or some features and advantages may be inferred or unambiguously determined from the description, or may be learned by implementing the above-mentioned technology of the present disclosure.

[0024] In order to make the above-mentioned objectives, features and advantages of the present disclosure more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic diagram of the structure of a load testing device provided by an embodiment of the present invention;

[0027] Figure 2A schematic diagram of the structure of another load testing device provided by an embodiment of the present invention;

[0028] Figure 3 A three-dimensional structural diagram of a load testing device provided by an embodiment of the present invention;

[0029] Figure 4 A pin diagram for driving a load component provided by an embodiment of the present invention;

[0030] Figure 5 A load control principle diagram provided by an embodiment of the present invention;

[0031] Figure 6 A test schematic diagram of a product to be tested provided by an embodiment of the present invention;

[0032] Figure 7 A control flow chart of a load testing device provided by an embodiment of the present invention;

[0033] Figure 8 A schematic diagram of the structure of a load testing system provided by an embodiment of the present invention;

[0034] Fig. 9 A schematic diagram of the structure of another load testing system provided by an embodiment of the present invention.

[0035] Icons: 100-load test device; 110-product to be tested; 120-controller module; 130-load module; 131-steady-state resistance module; 132-impact resistance module; 133-inductance module; 140-switch module; 150-data monitoring module; 160-touch screen; 170-communication module; 180-interface module; 200-load test system; 210-cloud server; 220-terminal device. DETAILED DESCRIPTION

[0036] 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. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0037] As mentioned in the background technology, currently, the commonly used loads on the market include DC electronic loads, AC electronic loads, fixed resistors, and sliding resistors. Among them, electronic loads are devices that consume electrical energy by controlling the conduction of internal power components such as MOSFETs or transistors and relying on the dissipated power of power tubes. During the working process, various electrical signals of the circuit must be continuously detected and corresponding control signals must be issued. There is a certain hysteresis time, and the voltage / current signals cannot be completely synchronized.

[0038] The electric tool products to be tested use AC / DC electronic loads, which may produce oscillations during high-frequency pulse operation, resulting in harmonics, voltage, and current spikes, which will affect the temperature rise of the power device field effect tube or transistor and related circuit parts of the circuit of the product to be tested, and even break down and burn them in serious cases. Fixed resistors and sliding resistors cannot automatically adjust the current changes caused by temperature rise changes, and cannot meet the test requirements. In the production of electric tool products to be tested, especially in the R&D stage, it is hoped that external influences such as power supply, load, and measuring tools can be eliminated, various functions can be strictly tested, and accurate parameters can be obtained.

[0039] Based on this, the load testing device and system provided by the embodiment of the present invention enable or disable the corresponding resistance and inductance through different combinations of relays or electronic switches, obtain different reactance values, provide high-quality loads for testing, and monitor the test data of the product to be tested through the data detection module, which can be applicable to test scenarios with power factor requirements. The combined pure resistive and resistive plus inductive loads can adapt to the load test of electronic switches powered by DC or AC.

[0040] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or moduled through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and modules without departing from the spirit of the present invention.

[0041] It should be noted that the diagrams provided in the present embodiment are only used to illustrate the basic concept of the present invention in a schematic manner, so the diagrams only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation can be changed at will, and the component layout type may also be more complicated. The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no technical substantive significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0042] To facilitate understanding of this embodiment, a load testing device disclosed in an embodiment of the present invention is first introduced in detail.

[0043] Example 1

[0044] The present invention provides a load testing device. Figure 1 The structural diagram of a load testing device shown in the figure, the load testing device 100 includes: a product to be tested 110, a controller module 120, a load module 130, a switch module 140 and a data monitoring module 150; the load module 130 includes an impact resistance module 132, a steady-state resistance module 131, and an inductance module 133;

[0045] The product to be tested 110, the inductance module 133, the impact resistance module 132 and the steady-state resistance module 131 are connected in sequence, and the controller module 120 is connected to the switch module 140; the steady-state resistance module 131 and the impact resistance module 132 each include a plurality of resistors, the inductance module 133 includes a plurality of inductors, the switch module 140 includes a plurality of relays or electronic switches, each resistor is connected in parallel with the relay or electronic switch; each inductor is connected in parallel with the relay or electronic switch; each resistor is connected in series with each inductor; the controller module 120 is connected to the switch module 140 for communication; the data monitoring module 150 is connected to the product to be tested 110;

[0046] The resistors included in the steady-state resistor module 131 and the impact resistor module 132 are all alloy resistors, which have high temperature resistance (up to 1300°C), stable electrical performance, and a temperature drift coefficient (1×10 -6 / ℃) of iron-chromium-aluminum alloy (0Cr21A16Nb), filled with electrical grade magnesium oxide powder (Sg-9) material. The heat sink adopts corrugated design, which greatly increases the heat dissipation surface of the resistor, so that the heat generated by the resistor during operation can be discharged in time through the cooling fan.

[0047] The inductor included in the above-mentioned inductor module 133 is composed of multiple groups of solid-state dry-type reactors. The iron core is made of high-quality low-loss cold-rolled silicon steel sheets, and the air gap is separated by epoxy laminated glass cloth plates to ensure that the air gap of the reactor does not change during operation; the fasteners of the reactor core column are made of non-magnetic materials to reduce eddy current heating during operation.

[0048] The controller module 120 is used to send control instructions to the switch module 140; the switches included in the switch module 140 can be numbered here, and the controller module 120 sends control instructions to the switch module 140. The control instructions can include control information of each relay or electronic switch in the switch module 140, and the control information is the opening or closing of the corresponding number of the relay or electronic switch. The controller module 120 can be a programmable logic device such as MCU (Microcontroller Unit, a control unit) / DSP (Digital Signal Processing, digital signal processing) / PLC (Programmable Logic Controller, programmable logic controller), and the controller module 120 can write a program to control the opening or closing of the switch module 140.

[0049] The switch module 140 is used to start or close the relay or electronic switch according to the control instruction; after receiving the control instruction sent by the controller module 120, the switch module 140 opens or closes the relay or electronic switch corresponding to the number according to the control information included in the control instruction. When the relay or electronic switch is turned on, the resistor or inductor connected in parallel with the relay or electronic switch is short-circuited and does not work; when the relay or electronic switch is turned off, the resistor or inductor connected in parallel with the relay or electronic switch works normally.

[0050] The data monitoring module 150 is used to monitor the test data of the product under test 110, and the test data includes at least one of the following: power information, voltage information, current information, frequency information and power factor of the product under test 110. During the process of the controller module 120 controlling the switch module 140, the data monitoring module 150 monitors the test data of the product under test 110 in real time.

[0051] A load testing device provided in this embodiment includes: a product to be tested, a controller module, a load module, a switch module and a data monitoring module; the load module includes a surge resistance module, a steady-state resistance module and an inductance module; the product to be tested, the inductance module, the surge resistance module and the steady-state resistance module are connected in sequence, and the controller module is connected to a relay or an electronic switch module; the steady-state resistance module and the surge resistance module each include multiple resistors, the inductance module includes multiple inductors, the relay or electronic switch module includes multiple relays or electronic switches, each resistor is connected in parallel with the relay or electronic switch; each inductor is connected in parallel with the relay or electronic switch; each resistor is connected in series with each inductor; the controller module is communicatively connected with the switch module; the data monitoring module is connected with the controller module and the product to be tested; the controller module sends a control instruction to the relay or electronic switch module according to the feedback data from the data monitoring module; the relay or electronic switch module is used to execute the start or shut down action according to the control instruction; the data monitoring module is used to monitor the test data of the product to be tested, and the test data includes at least one of the following: power information, voltage information, current information, frequency information and power factor of the product to be tested. This application controls the opening or closing of the switch module through the controller module, and uses different combinations of enabling or disabling relays or electronic switches to control the working state of the corresponding resistors and inductors, obtain different reactance values, provide high-quality loads for testing, and monitor the test data of the product to be tested through the data detection module, which can be applied to test scenarios with power factor requirements. The combined pure resistive and resistive plus inductive loads can adapt to the load test of electronic switches powered by DC or AC.

[0052] Example 2

[0053] The present invention provides another load testing device. Figure 2 The structural diagram of another load testing device shown in the figure, the load testing device 100 further includes: a touch screen 160, a communication module 170 and an interface module 180;

[0054] The above touch screen 160, its human-machine interaction data controls the combination information of the inductance module 133, the impact resistance module 132 and the steady-state resistance module 131 through the controller module 120 and displays the corresponding data; the controller module 120 is also used to control the opening or closing of the relay or electronic switch module according to the circuit feedback condition, and upload the data to the cloud server through the communication module using the server. The load test device 100 adds a touch screen 160 as a human-machine interaction interface. The touch screen 160 can receive and display the information input by the user. The controller module 120 generates a control instruction according to the test requirements, obtains the combination information, controls the corresponding relay or electronic switch to open or close, completes the combination of resistance and inductance, and provides a user-friendly operation experience.

[0055] The communication module 170 is used to provide a network environment for the load testing device 100; the communication module 170 may be a WiFi (Wireless Fidelity) module, a GPRS (General Packet Radio Service) module, or a Bluetooth (blue tooth) module.

[0056] The interface module 180 includes: an RS232 interface and an RS485 interface, and the interface module is used to provide an RS232 interface and an RS485 interface for external devices.

[0057] The controller module 120 is also used to control the switch module 140 according to the test data. When the interface module 180 is connected to the external device, the external device can read the various parameters of the controller module 120 and send corresponding instructions to the controller module 120 according to the test requirements. The controller module 120 changes the state of the current switch module 140 according to the received instructions. The external device can seize the control right according to the test requirements, turn off the adjustment function of the controller module 120, and make the load work in a stable set value state.

[0058] See also Figure 3 The three-dimensional structure diagram of a load testing device 100 is shown. In the load testing device 100, except for the power switch, emergency stop switch, power meter and touch screen 160 arranged outside the box, other modules in the load testing device 100 are arranged inside the box.

[0059] The steady-state resistance module 131 includes a plurality of resistors connected in series. The resistance values ​​of the resistors included in the steady-state resistance module 131 (which can be increased or decreased as needed) are: 0.1Ω, 0.2Ω, 0.4Ω, 0.8Ω, 1.6Ω, 3.2Ω, 6.4Ω, 25.6Ω and 51.2Ω. The resistors are customized according to the binary weight law: in ohms, 1 / 10 of 2 is selected. 0 , 2 1 , 2 2 , 2 3 , 2 4 , 2 5 , 2 6 , 2 7 , 2 8 , 2 9 ...resistors of resistance are paired according to a rule to obtain a resistance value that varies with an accuracy of 0.1Ω, and the resistance value range is 0 to 102.3Ω (or higher resistance values, which can be expanded as needed).

[0060] The impact resistance module 132 includes a plurality of resistors connected in series. The resistance values ​​of the resistors included in the impact resistance module 132 (which can be increased or decreased as needed) are: 0.1Ω, 0.2Ω, 0.4Ω, 0.8Ω, 1.6Ω, 3.2Ω, 6.4Ω, 25.6Ω and 51.2Ω. The resistors are customized according to the binary weight law: in ohms, 1 / 10 of 20, 2 1 , 2 2 , 2 3 , 2 4 , 2 5 , 2 6 , 2 7 , 2 8 , 2 9 ...resistors of resistance are paired according to a rule to obtain a resistance value that varies with an accuracy of 0.1Ω, and the resistance value range is 0 to 102.3Ω (or higher resistance values, which can be expanded as needed).

[0061] The inductor module 133 includes a plurality of inductors connected in series, and the inductor values ​​of the inductors included in the inductor module 133 (which can be increased or decreased as needed) are: 0.1mH, 0.2mH, 0.4mH, 0.8mH, 1.6mH, 3.2mH, 6.4mH, 12.8mH, 25.6mH and 51.2mH. Pure inductance is based on the binary weight rule, according to 1 / 10 of 20, 2 1 , 2 2 , 2 3 , 2 4 , 2 5 , 2 6 , 2 7 , 2 8 , 2 9 ...to obtain an inductance value with an accuracy of 0.1mH by pairing them together. The inductance value can be combined as needed. (The inductance value can be expanded as needed).

[0062] The above-mentioned inductor and resistor modules are connected in series, and an application program is written to control the corresponding relay or electronic switch to be turned on or off, so that the corresponding resistor and inductor are connected or disconnected accordingly, thereby obtaining different impedance values ​​to meet the test requirements. The above-mentioned resistor and inductor are further expanded, and an impact AC contactor is added to control the corresponding resistance network, which can be used for testing the electric tool product with electric impact or power factor requirements.

[0063] See also Figure 4The pin diagram of a load component drive shown in the figure provides the corresponding pins of steady-state resistance, impact resistance, power factor inductance control and impact relay or electronic switch control. The controller module 120 receives instructions from the touch screen 160 or the host computer, controls the level of the corresponding pin of the driver IC LUN2803, makes the corresponding relay or electronic switch work or not work, thereby making the resistance and inductance connected in parallel with the relay or electronic switch work or not work, realizing impedance transformation.

[0064] See also Figure 5 In the load control principle diagram shown in the figure, the internal resistance of the relay or electronic switch is very small, so no calculation is required. After adjusting the corresponding resistance value, use an ohmmeter to measure and correct the deviation. The specific transformation method is as follows:

[0065] a. Implementation of the steady-state resistance module 131:

[0066] For example: the relays or electronic switches K1, K3, K5, K7, and K9 are energized and their contacts are connected, so that the 0.1Ω, 0.4Ω, 1.6Ω, 6.4Ω, and 25.6Ω resistors connected in parallel with the relays or electronic switches do not work. The resulting resistance value is determined by the resistance connected in parallel with the relays or electronic switches that are not energized. At this time, the resistance value of the steady-state resistance module 131 is 0.2Ω+0.8Ω+3.2Ω+12.8Ω+51.2Ω=68.2Ω.

[0067] b. Implementation of the impact resistance module 132:

[0068] For example: the relays or electronic switches K12, K14, K16, K18, and K20 are energized and their contacts are connected, so that the 0.2Ω, 0.8Ω, 3.2Ω, 12.8Ω, and 51.2Ω resistors in parallel with the relays or electronic switches do not work. The resulting resistance value is determined by the resistance in parallel with the relays or electronic switches that are not energized. At this time, the resistance value of the impact resistance module 132 is 0.1Ω+0.4Ω+1.6Ω+6.4Ω+25.6Ω=34.1Ω.

[0069] c. Implementation of the inductor module 133:

[0070] For example: the relays or electronic switches K21, K23, K25, K27, and K29 ​​are energized and operated, and their contacts are connected, so that the 0.1mH, 0.4mH, 1.6mH, 6.4mH, and 25.6mH inductors connected in parallel with the relays or electronic switches do not work. The obtained inductance value is determined by the resistance connected in parallel with the relays or electronic switches that are not energized. At this time, the inductance value of the inductance module 133 is 0.2mH+0.8mH+3.2mH+12.8mH+51.2mH=68.2mH.

[0071] The above reactance combinations that can be achieved are:

[0072] Steady-state resistance module 131 = 68.2Ω, impulse resistance module 132 = 34.1Ω, inductance module 133 = 68.2mH, total reactance value = steady-state resistance module 131 + impulse resistance module 132 + inductance module 133 = 68.2Ω + 34.1Ω + 68.2mH = 102.3Ω + 68.2mH;

[0073] See also Figure 6 The test schematic diagram of a product to be tested is shown. The product to be tested may be an electric tool switch. The safety standard UL61058 specifies the voltage, current, impact current and corresponding ON / OFF working time of switches with different safety levels.

[0074] Under the specified voltage conditions:

[0075] 1. Impact resistance + inductance, connect the DC contactor to control the impact current, and limit the impact time by monitoring the conduction time of this current;

[0076] 2. Surge resistance + steady-state resistance + inductance, disconnect the DC contact controller to control the steady-state current, and limit the steady-state time by monitoring the conduction time of this current;

[0077] 3. Inductance is used to control the phase of voltage and current to achieve power factor requirements.

[0078] See also Figure 7 The flow control diagram of a load testing device 100 shown in the figure, the programmable logic control unit is the above-mentioned controller module 120, the user can exchange data with the programmable logic unit through the touch screen 160, after receiving the data, the programmable logic control unit generates a control instruction according to the combination signal, controls the working state of the corresponding relay or electronic switch in the switch module 140, and then controls the working state of the resistance network and the inductance network, the power meter monitors the test data of the product to be tested 110 in real time and feeds back to the programmable logic unit, the programmable logic unit dynamically adjusts the combination of resistance and inductance according to the fedback test data to enrich the test environment, the other control units are the above-mentioned external devices, when the external devices are connected, the dynamic adjustment function of the programmable logic unit can be turned off.

[0079] Example 3

[0080] The present invention also provides a load testing system. Figure 8 A structural diagram of a load testing system is shown, the load testing system 200 comprises: a cloud server 210 and the above-mentioned load testing device 100, the cloud server 210 and the load testing device 100 are communicatively connected;

[0081] The load testing device 100 is used to send the test data to the cloud server 210;

[0082] The cloud server 210 is used to receive test data.

[0083] See also Fig. 9 The structural diagram of another load testing system shown, the load testing system 200 may also include: a terminal device 220, the terminal device 220 is communicatively connected with the cloud server 210;

[0084] The terminal device 220 is used to obtain test data from the cloud server 210 .

[0085] The load testing system provided in the embodiment of the present invention has the same technical features as the load testing device provided in the above embodiment, so it can also solve the same technical problems and achieve the same technical effects.

[0086] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0087] In addition, in the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it 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 a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0088] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0089] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention 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 therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0090] Finally, it should be noted that the above embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that any person skilled in the art can still modify the technical solutions recorded in the above embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A load testing device, characterized in that: include: The product to be tested, the controller module, the load module, the switch module and the data monitoring module; the load module includes an impact resistance module, a steady-state resistance module and an inductance module; The product to be tested, the inductance module, the impact resistance module and the steady-state resistance module are connected in sequence, and the controller module is connected to the switch module; the steady-state resistance module and the impact resistance module each include a plurality of resistors, the inductance module includes a plurality of inductors, the switch module includes a plurality of relays or electronic switches, each of the resistors is connected in parallel with the relay or the electronic switch; each of the inductors is connected in parallel with the relay or the electronic switch; each of the resistors is connected in series with each of the inductors; the controller module is in communication connection with the switch module; the data monitoring module is connected to the product to be tested; The controller module is used to send control instructions to the switch module; The switch module is used to start or shut down the relay or the electronic switch according to the control instruction; The data monitoring module is used to monitor the test data of the product to be tested, and the test data includes at least one of the following: power information, voltage information, current information, frequency information and power factor of the product to be tested.

2. The load testing device according to claim 1, characterized in that: The load testing device further comprises a touch screen, the touch screen is used for human-computer interaction and displays combination information, the combination information is the combination information of the inductance module, the impact resistance module and the steady-state resistance module; The controller module is also used to generate the control instruction according to the test requirements to obtain the combination information.

3. The load testing device according to claim 1, characterized in that: The load testing device further includes a communication module, and the communication module is used to provide a network environment for the load testing device.

4. The load testing device according to claim 1, characterized in that: The steady-state resistance module includes a plurality of resistors connected in series, and the resistance value of the resistor included in the steady-state resistance module is 2 n / 10Ω, n is an integer.

5. The load testing device according to claim 1, characterized in that: The impact resistance module includes a plurality of resistors connected in series, and the resistance value of the resistor included in the impact resistance module is 2 m / 10Ω, m is an integer.

6. The load testing device according to claim 1, characterized in that: The inductor module includes a plurality of inductors connected in series, and the inductance value of the inductor included in the inductor module is 2 k / 10mH, k is an integer.

7. The load testing device according to claim 1, characterized in that: The load testing device further comprises an interface module, which comprises: an RS232 interface, an RS422 interface and an RS485 interface, and the interface module is used to provide the RS232 interface, RS422 interface and RS485 interface for external equipment.

8. The load testing device according to claim 7, characterized in that: The controller module is also used to control the switch module according to the test data. When the interface module is connected to the external device, the external device is used to turn off the adjustment function, which is the function of the controller module controlling the switch module according to the test data.

9. A load testing system, characterized in that: The load testing system comprises: a cloud server and a load testing device according to any one of claims 1 to 8, wherein the cloud server is in communication connection with the load testing device; The load testing device is used to send the test data to the cloud server; The cloud server is used to receive the test data.

10. The load testing system according to claim 9, characterized in that: The load testing system further includes a terminal device, wherein the terminal device is communicatively connected to the cloud server; The terminal device is used to obtain the test data from the cloud server.

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