A time division polling measurement system and method of multi-channel electrical parameters

Abstract

The application belongs to the technical field of electronic equipment testing and measurement, and provides a time-division polling measurement system and method for multi-channel electric parameters, comprising: a measurement device configured to measure electric parameters of a device under test; a program-controlled switch matrix, an input end of which is connected to a measurement channel of the measurement device; an output end of which comprises multiple and is respectively connected to multiple test points of the device under test; the program-controlled switch matrix is configured to create an independent measurement loop for each test point and is configured with a corresponding program-controlled switch in each measurement loop; and a main controller configured to control the program-controlled switch according to a preset timing sequence to switch the measurement device to each measurement loop in sequence to obtain the electric parameters required to be measured by the device under test. The application has the advantage that the program-controlled switch matrix is used to expand the measurement channel of the measurement instrument by applying the time-division polling technology, replacing the multiple-instrument scheme, greatly reducing the equipment cost and laboratory space occupation, and realizing unattended and efficient testing.

Description

Technical Field

[0001] This invention relates to the field of electronic equipment testing and measurement technology, and in particular to a time-division polling measurement system and method for multi-channel electrical parameters. Background Technology

[0002] When testing multi-port power devices (such as multi-port chargers and server power supplies) in the laboratory, it is necessary to monitor (such as voltage and current) simultaneously to calculate key indicators such as overall efficiency and load regulation. The traditional method is to use multiple power meters or data acquisition devices to connect to the AC power supply and each electronic load separately, resulting in high equipment costs, large space occupation, complex wiring, and difficulty in management.

[0003] There are some existing multi-channel switching test schemes, but they usually have the following defects: (1) They fail to systematically solve the safety and accuracy guarantee problem in AC / DC mixed signal switching; (2) They lack a complete automatic control, safety protection and data integrity management mechanism; (3) They do not build the system framework from the technical height of time division multiplexing, resulting in low resource utilization and poor scalability.

[0004] Therefore, there is an urgent need for a testing solution that is low-cost, space-saving, highly automated, and safe and reliable. Summary of the Invention

[0005] This invention provides a system and method that, by reusing a single measuring instrument and combining a high-reliability programmable switch matrix with a time-division polling control strategy, enables automatic, safe, and accurate measurement of electrical parameters at multiple test points and generates structured test data.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A time-division polling measurement system for multi-channel electrical parameters, comprising: A measuring device configured to measure the electrical parameters of a device under test; the measuring device includes at least one measuring channel. The programmable switch matrix has its input terminals connected to the measurement channels of the measuring equipment; its output terminals include multiple terminals, which are respectively connected to multiple test points of the device under test; the programmable switch matrix is ​​configured to create an independent measurement loop for each test point, and each measurement loop is equipped with a corresponding programmable switch; The main controller is configured to control the programmable switches according to a preset timing sequence to sequentially switch the measuring equipment to each measuring loop to obtain the electrical parameters to be measured by the device under test.

[0007] Furthermore, when the measuring device contains only one measuring channel, the programmable switch matrix will poll the measuring channel in a time-division multiplexing manner between the input test point and all output test points.

[0008] Furthermore, when the measuring device contains two measuring channels, its first measuring channel is fixedly connected to the input test point, and its second measuring channel performs time-division polling among all output test points through a programmable switch matrix.

[0009] Furthermore, it also includes a hardware interlock circuit, which is independent of the main controller and is configured to monitor the current flowing through the programmable switch matrix in real time and directly disconnect the programmable switch matrix when the current exceeds a safety threshold.

[0010] Furthermore, it also includes a host computer that communicates with the main controller and is configured to send test configuration parameters to the main controller and collect test data from the main controller.

[0011] Furthermore, the test configuration parameters should include at least one of the following: polling interval, number of polling cycles, and wait time after switching.

[0012] Furthermore, it also includes a safety protection module, which is configured to preset alarm thresholds for electrical parameters at each test point; the main controller compares the measured electrical parameters with the alarm thresholds and executes the predetermined alarm action based on the comparison result.

[0013] Furthermore, the safety protection module is integrated into the main controller and / or the host computer.

[0014] This invention also provides a multi-channel electrical parameter time-division polling measurement method, which utilizes the above-mentioned multi-channel electrical parameter time-division polling measurement system and includes the following steps: S1: The main controller is initialized, and all programmable switches in the programmable switch matrix are disconnected; S2: Start the polling loop and perform the following operations on any test point: close the programmable switch corresponding to the current test point; wait for the preset switching time; control the measuring device to perform measurement and read data; disconnect the programmable switch of the current test point; compare the read data with the alarm threshold, and execute the preset alarm action if the limit is exceeded; S3: After completing the measurement of all test points, wait until the next polling interval, and repeat step S2 until the preset number of polling times is reached.

[0015] Furthermore, prior to step S1, the following steps are also included: S0: The host computer sends a test sequence instruction containing multiple test conditions to the main controller; Furthermore, during the execution of step S2, the main controller changes the working state of the device under test while switching test points according to the test sequence instructions.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: (1) By using a programmable switch matrix and applying time-division polling technology to expand the measurement channels of the measuring instrument, the multi-instrument solution is replaced, which greatly reduces equipment costs and laboratory space occupation. In addition, the system supports complex automated test sequences, realizing unattended and efficient testing. (2) The system supports flexible configuration from single channel to multi-channel, and users can choose the best solution according to the comprehensive requirements of test accuracy and cost, which has a wide range of applications; (3) Combining software alarm and hardware interlock dual security mechanisms, it provides comprehensive protection from software to hardware, effectively preventing equipment damage. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the system architecture provided in this embodiment; Figure 2 This is a schematic diagram of the system signal flow provided in this embodiment; Figure 3 This is a flowchart illustrating the time-division polling method provided in this embodiment. Detailed Implementation

[0019] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0020] like Figure 1 and Figure 2 As shown, this embodiment provides a time-division polling measurement system for multi-channel electrical parameters, which includes: a measurement device, a programmable switch matrix, a main controller, and an optional host computer and safety protection module.

[0021] The measuring device is configured to measure the electrical parameters of the device under test, including at least voltage and current. The measuring device has at least one measurement channel. The main controller, serving as the system's control core, is equipped with a communication interface. The programmable switch matrix, controlled by the main controller, has its inputs connected to the measurement channels of the measuring device, and its multiple outputs connected to multiple test points of the device under test.

[0022] The host computer communicates with the main controller and is used to send out test configuration parameters, as well as receive, display and store test data from the main controller. The test configuration parameters include polling interval, number of polling, and waiting time after switching.

[0023] The measuring device is the direct execution unit for acquiring electrical parameter data in this system. Its core function is to accurately measure basic electrical parameters such as voltage and current, and to calculate derived parameters such as power and efficiency. Typically, this device is a high-precision digital power meter or a data acquisition device with equivalent precision.

[0024] Specifically, when the system selects a power timer with only one measurement channel, that single measurement channel will serve as the system's sole channel. In this case, the programmable switch matrix needs to connect this measurement channel to all test points, including the input points of the device under test (e.g., one input test point and N output test points). The main controller then controls the programmable switch matrix to sequentially connect this measurement channel to each test loop in time, achieving time-division multiplexing of all points.

[0025] More preferably, a power meter with at least two measurement channels, such as a dual-channel power meter, is used. This configuration allows for an optimized measurement strategy. Typically, the first measurement channel is fixedly and permanently connected to the input test point of the device under test (DUT) for continuous or synchronous monitoring of input electrical parameters (such as input voltage, current, and power). The second measurement channel is connected to the input of a programmable switch matrix, controlled by the main controller, and polls and switches between all output test points. A significant advantage of this configuration is that at any given measurement moment, the system can synchronously acquire both the input parameters and the parameters of a specific output, enabling real-time calculation of the instantaneous efficiency of the output loop or synchronous comparison of input / output parameters. This results in stronger data correlation and is particularly suitable for tests requiring synchronous input and output data, such as efficiency and ripple.

[0026] The programmable switch matrix plays a crucial role in switching physical signal paths. Essentially, it is a network composed of multiple programmable switches, and its topology is controlled by the main controller.

[0027] The input terminals of the programmable switch matrix are connected to one or more measurement channels of the measuring device. Its output terminals contain multiple independent ports, each connected to a test point on the device under test that needs to be monitored. Each test point corresponds to an independent measurement loop within the switch matrix, consisting of several programmable switches.

[0028] To ensure measurement accuracy, especially to eliminate voltage drop errors caused by lead resistance under high current, the programmable switch matrix of this system is preferably configured with a four-wire measurement circuit for each test point. For a single test point, its corresponding relay group contains four independent programmable switches, which are used to connect the high and low induction lines for voltage measurement and the high and low drive lines for current drive, respectively. This design extends the voltage sampling point directly to the vicinity of the terminals of the device under test, ensuring that the voltage measured is the true terminal voltage of the measured point, rather than the voltage after the voltage drop through the switches and cables, thereby greatly improving the accuracy of voltage and current measurements.

[0029] Therefore, in response to the switching commands of the main controller, the programmable switch matrix connects only the measurement circuit corresponding to the target test point to the measuring equipment at any given time, while ensuring that all other circuits are reliably disconnected. This achieves one-time, one-channel exclusive multiplexing of the measuring equipment channel and multiple measured points in terms of physical connection.

[0030] The main controller is the control core and logic scheduling center for the automated operation of the system, and is usually implemented by a microcontroller (MCU), programmable logic controller (PLC) or embedded industrial computer.

[0031] The main controller executes precise time-division polling logic. During operation, the main controller generates triggers at preset, cyclical polling intervals. Within each polling cycle, it performs a standard operating sequence for each target test point according to the list order: a) controlling the programmable switch matrix to close the relay group corresponding to the test point; b) waiting for a preset post-switch waiting time to eliminate relay contact bounce and circuit transients, ensuring measurement stability; c) sending a trigger signal to the measuring device, commanding it to perform the measurement, and subsequently reading the measurement data; d) controlling the programmable switch matrix to open the relay group for the test point. It then immediately switches to the next test point in the list, repeating this process until all points within a cycle are measured. Afterward, the main controller waits until the next polling interval time point arrives, starting a new cycle, and repeating this cycle until the preset number of polling times is reached.

[0032] The host computer is typically a computer running dedicated testing software. Users can graphically configure the entire testing task through the host computer software. This includes: selecting the test points to be polled, setting the electrical parameter alarm thresholds for each test point, defining test sequence instructions (e.g., test conditions containing multiple different input voltages and load conditions), and setting core timing parameters (polling interval, number of polls, and waiting time after switching), etc.

[0033] The test sequence instructions issued by the host computer are key to achieving fully automated complex testing. For example, an instruction might specify: when measuring test point A, synchronously control the programmable power supply to output 110V and control electronic load 1 to operate in constant current mode; when measuring test point B, switch to controlling the power supply to output 220V and load 2 to operate in constant power mode. While switching test points, the main controller coordinates and controls these peripheral devices to change their operating states, thereby achieving automated traversal testing across multiple operating conditions.

[0034] Meanwhile, the host computer receives and parses the data packets uploaded by the main controller in real time, dynamically displaying the parameter changes at each test point in various formats such as numbers, real-time curves, and tables. All data, along with test configurations, timestamps, alarm records, and other information, are saved in a structured format for easy data analysis, report generation, and quality traceability.

[0035] The safety protection module is integrated into the main controller and / or the host computer, and it contains preset alarm thresholds for the electrical parameters of each test point. The main controller compares the data read by the measuring device with the alarm thresholds and performs recording, reporting, or emergency stop operations according to the alarm level.

[0036] In addition, this system includes a hardware interlock circuit (not shown in the figure). This circuit is independent of the main controller and monitors the current signal in real time through a hardware comparator. When the current exceeds the limit, it directly cuts off the power supply or load, forming a safety protection loop. It directly and in real time monitors the total current or critical branch current flowing through the main current path of the programmable switch matrix using a current sensor (such as a Hall sensor or a sampling resistor + isolation operational amplifier). This analog signal is compared with a hardware-set safety threshold. Once the monitored current exceeds this hardware threshold, the power supply to the programmable switch matrix or the main load circuit is directly cut off. This process does not involve any software judgment, so even if the main controller program crashes, freezes, or communication is interrupted, it still provides effective protection, preventing overcurrent from burning out relay contacts or causing safety accidents.

[0037] like Figure 3 As shown, this embodiment also provides a time-division polling method for multi-channel electrical parameters, including the following steps: Step S0: The user plans the test task through the host computer software, compiles a test sequence instruction containing multiple test conditions, and sets various parameters. The host computer sends this instruction to the main controller; Step S1: After the main controller is powered on or receives the start command, it first performs a safety initialization operation: sends a command to the programmable switch matrix to ensure that all programmable switches inside are in the off state, so that the system is in a certain and safe no-load start state. Step S2: Start the polling loop. The main controller starts the loop. In each cycle, for each point in the test point list, perform the following operations sequentially: S2.1: Control the programmable switch matrix to close the relay group corresponding to the current target test point i, and connect the measuring device to the circuit at that point.

[0038] S2.2: The program waits for a preset time to allow the relay contacts to stabilize and transient processes in the circuit (such as the charging and discharging of inductors and capacitors) to subside, ensuring the accuracy of subsequent measurement data.

[0039] S2.3: Send a trigger measurement command to the measuring device, and then read the voltage, current and other measurement data of the test point from the measuring device.

[0040] S2.4: Compare the read data with the preset alarm threshold for this test point in real time. If the data exceeds the limit, execute the preset alarm action.

[0041] S2.5: Control the programmable switch matrix to disconnect the relay group at the current test point i. Then, package the measurement data along with the test point number i, timestamp, current test condition, and other information to form a complete data recording unit, and send it to the host computer.

[0042] Then jump to S2.1 to start measuring the next test point; if all test points have been measured within a polling cycle, proceed to the next step.

[0043] Step S3: After completing one cycle of Step S2, the main controller calculates the elapsed time since the start of the current cycle. If the preset polling interval has not been reached, it waits until the next polling time arrives. Once the interval arrives, the next polling cycle begins immediately, i.e., it jumps back to the beginning of Step S2. This cycle repeats until the number of completed polling cycles reaches the preset total number, at which point the entire test task ends.

[0044] Throughout the process, if test sequence instructions are enabled, the main controller will also synchronously change the output mode of the programmable power supply or the mode of the programmable load at the appropriate time when switching test points to match different test conditions.

[0045] For example, let's take testing a 65W three-port USB-C charger as an example. A dual-channel power meter is used, with channel A fixedly connected to the charger's input front end, and channel B connected to the input of a programmable switch matrix. The three outputs of the programmable switch matrix are connected to the three output ports of the charger, and then connected to a programmable AC power supply or a programmable electronic load.

[0046] First, the user sets the timing parameters on the host computer: polling interval 5 seconds, switch wait 200ms.

[0047] The main controller then begins operation. It disconnects all relays and controls the power supply and load to enter the set state. Subsequently, it initiates a 2-second timed loop. In the first loop, it first closes the switch of output port 1, waits 150ms, reads power meter channels B and A to determine if the voltage is normal, then disconnects the relays and packages and sends the data. It then switches to output port 2 in a very short time and repeats the process. After completing measurements at all three ports, it waits exactly 2 seconds before starting the next loop. The host computer plots the input power, output voltage at each port, and overall efficiency ((P_out1+P_out2+P_out3) / P_in) over time in real time. After one hour, the test automatically ends, and the software generates a report providing the average voltage of each port, ripple, and overall average efficiency.

[0048] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0049] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0050] Furthermore, in this invention, descriptions involving terms such as "first," "second," and "a" are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

Claims

1. A time-division polling measurement system for multi-channel electrical parameters, characterized in that, include: A measuring device configured to measure electrical parameters of a device under test; the measuring device includes at least one measuring channel. A programmable switch matrix, the input of which is connected to the measurement channel of the measuring device; Its output terminals include multiple ones, and are respectively connected to multiple test points of the device under test; The programmable switch matrix is ​​configured to create an independent measurement loop for each test point, and a corresponding programmable switch is configured in each measurement loop; The main controller is configured to control the programmable switch according to a preset timing sequence to sequentially switch the measuring device to each measuring circuit to obtain the electrical parameters to be measured by the device under test.

2. The time-division polling measurement system for multi-channel electrical parameters according to claim 1, characterized in that, When the measuring device contains only one measuring channel, the programmable switch matrix will poll the measuring channel in a time-division multiplexing manner between the input test point and all output test points.

3. The time-division polling measurement system for multi-channel electrical parameters according to claim 1, characterized in that, When the measuring device contains two measuring channels, its first measuring channel is fixedly connected to the input test point, and its second measuring channel performs time-division polling among all output test points through the programmable switch matrix.

4. The time-division polling measurement system for multi-channel electrical parameters according to claim 1, characterized in that, It also includes a hardware interlock circuit, which is independent of the main controller and is configured to monitor the current flowing through the programmable switch matrix in real time and directly disconnect the programmable switch matrix when the current exceeds a safety threshold.

5. The time-division polling measurement system for multi-channel electrical parameters according to claim 1, characterized in that, It also includes a host computer, which is connected to the main controller and configured to send test configuration parameters to the main controller and collect test data from the main controller.

6. The time-division polling measurement system for multi-channel electrical parameters according to claim 5, characterized in that, The test configuration parameters include at least one of the following: polling interval, number of polling attempts, and waiting time after switching.

7. The time-division polling measurement system for multi-channel electrical parameters according to claim 5, characterized in that, It also includes a safety protection module, which is configured to preset alarm thresholds for electrical parameters at each test point; the main controller compares the measured electrical parameters with the alarm thresholds and executes a predetermined alarm action based on the comparison result.

8. A time-division polling measurement system for multi-channel electrical parameters according to claim 7, characterized in that, The security protection module is integrated into the main controller and / or the host computer.

9. A multi-channel electrical parameter time-division polling measurement method, utilizing the multi-channel electrical parameter time-division polling measurement system according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1: The main controller is initialized, and all programmable switches in the programmable switch matrix are disconnected; S2: Start the polling loop and perform the following operations on any test point: close the programmable switch corresponding to the current test point; wait for the preset switching time; control the measuring device to perform measurement and read data; disconnect the programmable switch of the current test point; compare the read data with the alarm threshold, and execute the preset alarm action if the limit is exceeded; S3: After completing the measurement of all test points, wait until the next polling interval, and repeat step S2 until the preset number of polling times is reached.

10. The time-division polling method for multi-channel electrical parameters according to claim 7, characterized in that, Before step S1, the following is also included: S0: The host computer sends a test sequence instruction containing multiple test conditions to the main controller; Furthermore, during the execution of step S2, the main controller changes the working state of the device under test while switching test points according to the test sequence instructions.

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