Multi-channel conductive slip ring transient interruption high-precision detector based on adjustable threshold comparison

Abstract

The invention discloses a multi-channel conductive slip ring transient interruption high-precision detector based on adjustable threshold comparison, which mainly relates to the technical field of conductive slip ring detection, and comprises a power supply unit, an adjustable reference resistor unit, a multi-path high-slew-rate constant-current excitation source, a data acquisition and processing unit taking an FPGA as a core, and a man-machine interaction unit, a continuously adjustable reference voltage is generated through a path of constant current excitation and a knob type precise adjustable resistor and is used as a transient-break resistance threshold reference; the other multi-path constant current excitation synchronously acts on each channel of the tested slip ring; the FPGA utilizes a high-frequency clock generated by a phase-locked loop to carry out real-time comparison and nanosecond precision timing on response voltage and reference voltage of each channel in parallel; according to the invention, continuous adjustment and visualization of the transient-current resistance threshold can be realized, and the detection precision is greatly improved.

Description

Technical Field

[0001] This invention mainly relates to the field of conductive slip ring detection technology, specifically to a high-precision multi-channel conductive slip ring instantaneous breakage detector based on adjustable threshold comparison. Background Technology

[0002] Conductive slip rings are key components for solving the transmission of electrical energy and signals between the relatively rotating and stationary parts of equipment, and are widely used in various fields. One of their core performance indicators is contact reliability, that is, there should be no instantaneous interruption (interruption) of signal or power during high-speed rotation. The interruption time is extremely short, usually on the order of microseconds or even nanoseconds, but it may have catastrophic consequences for the operation of the system.

[0003] Existing transient interruption detectors suffer from the following technical challenges: 1. The detection threshold is fixed and singular. Most devices use a fixed comparison level (such as generated by voltage division through a fixed resistor) as the benchmark for instantaneous interruption judgment. It is impossible to flexibly and continuously set the instantaneous interruption resistance threshold according to different test standards or slip ring specifications (for example, users cannot accurately set the threshold to 10Ω or 20Ω).

[0004] 2. Limited number of channels: Due to limitations in circuit architecture and control methods, conventional transient interrupt testers typically have fewer than 15 detection channels, making it difficult to meet the synchronous testing requirements of multiple slip rings (such as dozens to hundreds of channels).

[0005] 3. Low detection accuracy: Due to the limitations of the excitation source response speed and the timing accuracy of the controller, the detection accuracy of traditional equipment is usually around 100ns, which cannot accurately capture and measure transient events with shorter durations.

[0006] Therefore, there is an urgent need for a transient interruption detection device that can achieve continuously adjustable threshold, support multi-channel synchronous detection, and has nanosecond-level high precision. Summary of the Invention

[0007] (a) Technical problems to be solved In view of the above-mentioned problems, the present invention provides a high-precision detector for transient interruption resistance based on adjustable threshold comparison of multi-channel conductive slip ring, which can realize continuous adjustment and visualization of transient interruption resistance threshold and significantly improve detection accuracy.

[0008] (II) Technical Solution To address the aforementioned technical problems, this invention provides a high-precision multi-channel conductive slip ring transient interruption detector based on adjustable threshold comparison, comprising: The power supply unit is used to convert external AC power into DC power required by the system, specifically converting 220VAC mains power into 24VDC.

[0009] An adjustable reference resistor unit is used to generate a continuously adjustable resistance reference value; the current resistance value of this resistor is measured and displayed in real time through a resistance acquisition circuit.

[0010] A multi-channel high-voltage slew rate constant current excitation source includes N+1 outputs. N outputs are detection channel excitation sources, used to provide constant current excitation to N tested conductive slip ring channels. The N+1th output is a reference channel excitation source, used to provide the same constant current to the adjustable reference resistor unit to generate a reference voltage signal. The N outputs (e.g., 100 outputs) are respectively connected to the N tested conductive slip ring channels, providing a constant excitation current I. The N+1th output is connected to the adjustable reference resistor unit R_ref, thereby generating a reference voltage V_ref = I × R_ref across its terminals. Since the current in all channels is the same, V_ref directly corresponds to the resistance threshold R_ref.

[0011] The data acquisition and processing unit is based on a field-programmable gate array (FPGA). This FPGA uses phase-locked loop (PLL) technology to configure the system frequency at 500MHz or higher to generate nanosecond-level time ticks. The human-computer interaction unit is used to set parameters and display status. The data acquisition and processing unit simultaneously acquires the response voltage signals of N detection channels and the reference voltage signal, and compares the response voltage signal of each detection channel with the reference voltage signal in real time. When the response voltage of any detection channel is higher than the reference voltage, it is determined that the channel has experienced a momentary interruption, and a timing based on nanosecond-level time ticks is started. When the duration of the momentary interruption exceeds a preset alarm time threshold, the momentary interruption alarm status of the channel is output.

[0012] Furthermore, the adjustable reference resistor unit is a knob-type precision adjustable resistor, whose resistance value variation range covers the resistance threshold range for instantaneous interruption determination. The data acquisition and processing unit calculates the current resistance value of the adjustable reference resistor unit based on the current and reference voltage signals of the reference channel excitation source, and displays it through the human-machine interaction unit.

[0013] Furthermore, the data acquisition and processing unit uses FPGA to process the comparison and timing logic of all N detection channels in parallel, enabling synchronous acquisition and judgment of the transient states of 100 or more channels.

[0014] Furthermore, the human-machine interaction unit is a serial port touch screen, used to set alarm time thresholds, display the real-time status of each channel, instantaneous interruption history, and the current resistance value of the adjustable reference resistor unit.

[0015] Furthermore, the output current slew rate of the multi-channel high-voltage slew rate constant current excitation source is not less than 1A / μs to ensure the establishment time of the response voltage of the detection channel when a transient interruption occurs, thereby making the transient interruption detection accuracy of the system better than 10ns.

[0016] Furthermore, the system time clock generated by the data acquisition and processing unit through the phase-locked loop technology is 2ns.

[0017] The beneficial effects of this invention compared to existing technologies are: 1. Continuously adjustable and visualized threshold: through "one-way excitation source + 1. **Adjustable Resistor for Reference Voltage:** This scheme transforms the traditional fixed, discrete resistance threshold setting into a continuously adjustable one, enabling real-time acquisition and display of the currently set threshold resistance value. This significantly enhances the device's flexibility and user experience. 2. **High Channel Expansion Capability:** Utilizing an FPGA as the core processor, its parallel processing architecture is naturally suited for synchronous acquisition and real-time judgment of multi-channel data, easily achieving synchronous detection of 100 or more channels, breaking through the bottleneck of traditional instruments in terms of channel quantity. 3. **Nanosecond-Level High Detection Accuracy:** By combining a high-voltage slew rate constant current excitation source (ensuring rapid voltage signal establishment) and FPGA-based high-frequency clock timing (providing a 2ns time resolution), the overall detection accuracy of the system is improved from the conventional 100ns level to a level better than 10ns, enabling the capture of even brief transient interruptions. 4. **Overall, the core advantage of this invention lies in its FPGA-based parallel comparison and nanosecond-level timing architecture, combined with a high-voltage slew rate constant current source, achieving multi-channel, high-precision, real-time reliable transient interruption detection. This integrated approach addresses several technical pain points in existing technologies, providing a significant technological breakthrough in the field of transient interruption detection instruments. Attached Figure Description

[0018] Figure 1 This is a flowchart of the instantaneous interruption judgment in the data acquisition and processing unit of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments. The invention is explained through illustrative embodiments and descriptions, but is not intended to limit the invention.

[0020] Example: Figure 1 The multi-channel conductive slip ring transient high-precision detector shown includes: a power supply unit, which converts 220VAC mains power into 24VDC and other DC voltages required by the system to power the entire system.

[0021] The adjustable reference resistor unit is a knob-type precision adjustable resistor whose resistance value can be continuously adjusted by the user. The resistance value change range covers the resistance threshold range for instantaneous interruption judgment. The current resistance value of the resistor is measured and displayed in real time through the resistance value acquisition circuit. Specifically, the current resistance value of the adjustable reference resistor unit is calculated by the data acquisition and processing unit based on the current and reference voltage signals of the reference channel excitation source, and then displayed through the human-machine interaction unit.

[0022] The multi-channel high-voltage slew rate constant current excitation source contains N+1 outputs. N of these are excitation sources for detection channels, where N is a positive integer greater than or equal to 1 (e.g., 100 channels), and are connected to the N tested conductive slip ring channels, providing a constant excitation current I for each channel. The N+1th channel is the excitation source for the reference channel, connected to an adjustable reference resistor unit R_ref, thereby generating a reference voltage V_ref = I × R_ref across its terminals. Since the current in all channels is consistent, V_ref directly corresponds to the resistance threshold R_ref.

[0023] R_ref stands for Reference Resistance, which is the reference resistance (adjustable) referred to in this invention, and V_ref stands for Reference Voltage, which is the reference voltage referred to in this invention.

[0024] The output current slew rate of the multi-channel high-voltage constant current excitation source is not less than 1A / μs to ensure the establishment time of the response voltage of the detection channel when a transient interruption occurs, thereby making the transient interruption detection accuracy of the system better than 10ns.

[0025] The data acquisition and processing unit, which is the core of this system, is a field-programmable gate array (FPGA). The FPGA uses phase-locked loop technology to configure the system frequency at 500MHz or higher to generate nanosecond-level time clocks. Specifically, the system time clock generated by the phase-locked loop technology is 2ns.

[0026] 2ns is equivalent to 2 nanoseconds. When the system's main frequency is configured at 500MHz (MHz: megahertz), the FPGA can perform 500 million clock cycles in 1 second. Such a short time interval is very important and necessary for the accurate acquisition, processing and transmission of data.

[0027] The data acquisition and processing unit simultaneously acquires the response voltage signals of N detection channels and the reference voltage signal, and compares the response voltage signal of each detection channel with the reference voltage signal in real time. The data acquisition and processing unit uses FPGA to process the comparison and timing logic of all N detection channels in parallel, enabling synchronous acquisition and judgment of the transient status of 100 or more channels.

[0028] When the response voltage of any detection channel is higher than the reference voltage, it is determined that the channel has experienced a momentary interruption, and timing based on nanosecond-level time ticks is started; when the duration of the momentary interruption exceeds the preset alarm time threshold, the momentary interruption alarm status of the channel is output.

[0029] Specifically, the unit simultaneously acquires the voltage V_ch and reference voltage V_ref of all tested channels; the FPGA internally configures a high-speed comparator and a high-precision timer in parallel for each channel; when V_ch > V_ref of a certain channel, the comparator immediately flips, determines that the resistance of the channel exceeds R_ref, a momentary interruption occurs, and starts the timer corresponding to the channel; the timer accumulates the duration of the momentary interruption in 2ns as the minimum unit, and when the duration exceeds the preset alarm time (such as 1μs), the FPGA sets the alarm status flag of the channel.

[0030] 1μs is 1 microsecond, and 1μs = 500 2ns clock cycles. The FPGA accumulates the number of clock ticks through a counter to achieve high-precision measurement of the duration of the transient interruption.

[0031] The human-machine interaction unit is a serial port touch screen, used to set alarm time thresholds, display the real-time status of each channel, instantaneous interruption history, and information such as the current resistance value and duration of the adjustable reference resistor unit.

[0032] Working principle of this invention: See Figure 1 After the system is powered on, the power supply unit starts working, converting the AC power into the DC power required by the system (converting the external 220VAC mains power into the DC voltage 24VDC required by the system) to power the various units of the present invention. The user sets the alarm time through the human-machine interaction unit (serial port touch screen) and rotates the precision adjustable resistor to set its resistance value to the required instantaneous interruption threshold (such as 20Ω); at this time, the touch screen displays the currently set 20Ω resistance value in real time.

[0033] The multi-channel high-voltage slew rate constant current excitation source outputs 101 constant currents, of which 100 channels are connected to the 100 channels of the slip ring under test, and the 101st channel is connected to a 20Ω adjustable reference resistor to generate a reference voltage V_ref.

[0034] The FPGA on the data acquisition board operates at a frequency of 500MHz, sampling the voltage and V_ref of 100 channels in parallel. Inside the FPGA, the voltage of each detection channel is compared with V_ref within one clock cycle. If the voltage of the Kth channel is higher than V_ref, the FPGA immediately recognizes the event within 2ns and starts the counter for the Kth channel to begin accumulating.

[0035] If the high-level state lasts for 5 clock cycles (i.e., 10ns), the FPGA determines that a valid transient fault has occurred in the Kth channel and sends an alarm message to the host computer or touch screen through the communication interface. At the same time, it records the duration of the transient fault. Users can set the trigger threshold for the transient fault time through the host computer or serial port screen to meet the needs of different test scenarios.

[0036] This invention comprises a power supply unit, an adjustable reference resistor unit, multiple high-voltage slew rate constant current excitation sources, an FPGA-based data acquisition and processing unit, and a human-machine interface unit. The core functionality involves generating a continuously adjustable reference voltage using a constant current excitation source and a rotary adjustable resistor, serving as the threshold voltage for transient resistance. Multiple other constant current excitation sources synchronously apply to each channel of the slip ring under test. The FPGA utilizes a high-frequency clock generated by a phase-locked loop to perform real-time comparisons and nanosecond-level timing of the response voltages of each channel with the reference voltage. This invention achieves continuous adjustment and visualization of the transient resistance threshold, supports simultaneous detection of over 100 channels, and improves detection accuracy from the traditional 100ns level to better than 10ns, effectively solving the technical problems of fixed thresholds, limited channel count, and low accuracy in existing equipment.

[0037] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A high-precision multi-channel conductive slip ring instantaneous interruption detector based on adjustable threshold comparison, characterized in that, include: The power supply unit is used to convert external AC power into DC power required by the system. An adjustable reference resistor unit is used to generate a continuously adjustable resistance reference value; A multi-channel high-voltage slew rate constant current excitation source includes N+1 outputs, where N are detection channel excitation sources used to provide constant current excitation for N tested conductive slip ring channels; the N+1th channel is a reference channel excitation source used to provide the same constant current to the adjustable reference resistor unit to generate a reference voltage signal. The data acquisition and processing unit is based on a field-programmable gate array (FPGA). This FPGA uses phase-locked loop (PLL) technology to configure the system frequency at 500MHz or higher to generate nanosecond-level time ticks. The human-computer interaction unit is used to set parameters and display status. The data acquisition and processing unit simultaneously acquires the response voltage signals of N detection channels and the reference voltage signal, and compares the response voltage signal of each detection channel with the reference voltage signal in real time. When the response voltage of any detection channel is higher than the reference voltage, it is determined that the channel has experienced a momentary interruption, and timing based on nanosecond-level time ticks is started; when the duration of the momentary interruption exceeds the preset alarm time threshold, the momentary interruption alarm status of the channel is output.

2. The high-precision multi-channel conductive slip ring instantaneous interruption detector based on adjustable threshold comparison according to claim 1, characterized in that, The adjustable reference resistor unit is a knob-type precision adjustable resistor, whose resistance value variation range covers the resistance threshold range for instantaneous interruption determination. The data acquisition and processing unit calculates the current resistance value of the adjustable reference resistor unit based on the current and reference voltage signals of the reference channel excitation source, and displays it through the human-machine interaction unit.

3. The high-precision multi-channel conductive slip ring instantaneous interruption detector based on adjustable threshold comparison according to claim 1, characterized in that, The data acquisition and processing unit uses FPGA to process the comparison and timing logic of all N detection channels in parallel, enabling synchronous acquisition and judgment of the transient status of 100 or more channels.

4. The high-precision multi-channel conductive slip ring instantaneous interruption detector based on adjustable threshold comparison according to claim 2, characterized in that, The human-machine interaction unit is a serial port touch screen, used to set alarm time thresholds, display the real-time status of each channel, instantaneous interruption history, and the current resistance value of the adjustable reference resistor unit.

5. A high-precision multi-channel conductive slip ring instantaneous interruption detector based on adjustable threshold comparison according to claim 1, characterized in that, The output current slew rate of the multi-channel high-voltage slew rate constant current excitation source is not less than 1A / μs, so as to ensure the establishment time of the response voltage of the detection channel when a transient interruption occurs, thereby making the transient interruption detection accuracy of the system better than 10ns.

6. A high-precision multi-channel conductive slip ring instantaneous failure detector based on adjustable threshold comparison according to any one of claims 1 to 5, characterized in that, The system time cycle generated by the data acquisition and processing unit through the phase-locked loop technology is 2ns.

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