Strong and weak electric ground self-adapting isolation circuit and control method for CT system

Abstract

The application discloses a strong and weak electric ground self-adaptive isolation circuit for a CT system, comprising a layered suspended ground module, a working condition acquisition module, a main control judgment module and an isolation switching module, through a dynamic suspended ground architecture, a working condition self-adaptive dynamic switching of a ground isolation mode is realized, efficient operation in common ground is maintained under a low interference working condition, and automatic layered isolation is realized under a strong interference working condition, the circuit anti-interference ability, response speed, low energy consumption and long-term operation stability are considered, and the core pain points of traditional technologies are solved.

Description

Technical Field

[0001] This invention relates to the field of information processing technology, specifically to an adaptive isolation circuit and control method for strong and weak current ground in a CT system. Background Technology

[0002] In CT equipment that integrates both strong and weak current circuits, the design of strong and weak current isolation and grounding is crucial for ensuring equipment operational stability, signal accuracy, and electrical safety. The strong current side is susceptible to interference sources such as voltage fluctuations, load abrupt changes, high-frequency noise, electromagnetic radiation, and surge pulses. If this interference enters the weak current control circuit, it can cause signal distortion, data drift, and control module malfunctions. In severe cases, it can lead to chip burnout, equipment crashes, and system failures. Therefore, a proper design for strong and weak current isolation and grounding is a core means of improving the equipment's electromagnetic compatibility performance.

[0003] Currently, the industry's strong and weak current grounding isolation solutions are only divided into two fixed static architectures, which have irreconcilable technical contradictions. The specific defects are as follows: The first is a rigid, completely isolated architecture. This solution permanently and completely separates the high-voltage ground from the low-voltage ground. Although it has a strong anti-interference capability and can effectively isolate high-voltage and high-frequency electromagnetic interference, the long-term fixed isolation structure will lead to inconsistent reference standards for strong and weak electrical signals, poor circuit signal synchronization, increased response delay, and a significant decrease in dynamic working performance.

[0004] Secondly, there is the fixed common ground architecture. This scheme uses the same grounding reference for both strong and weak current systems. It has a simple circuit structure, good signal synchronization, fast response speed, and no additional isolation device losses, resulting in high operational stability under normal operating conditions. However, this scheme has weak anti-interference capabilities. Under conditions such as complex electromagnetic environments, power grid fluctuations, load changes, and high-frequency interference, various interferences on the strong current side can be directly coupled to the weak current control system through the common ground loop, which can easily cause problems such as signal distortion, control failure, and hardware damage. The equipment's fault tolerance and environmental adaptability are extremely low.

[0005] In summary, existing technologies are all static, fixed designs with a "one-size-fits-all" approach, which cannot dynamically adjust the isolation and grounding status according to actual working conditions. There is always a core contradiction between anti-interference performance and operating efficiency, low energy consumption, and high response speed, making it difficult to adapt to complex and ever-changing CT working scenarios. Summary of the Invention

[0006] The main objective of this invention is to provide an adaptive isolation circuit and control method for strong and weak ground in CT systems, in order to overcome the shortcomings of related technologies.

[0007] To achieve the above objectives, according to a first aspect of the present invention, a strong and weak current adaptive isolation circuit for a CT system is provided, comprising a layered floating ground module, a working condition acquisition module, a main control judgment module, and an isolation switching module; the layered floating ground module includes a strong current ground plane and a weak current ground plane, which are independently arranged in layers, and a floating buffer branch is provided between them; the working condition acquisition module is connected to the strong current circuit and the weak current circuit respectively, and is used to acquire circuit working condition parameters in real time; the input terminal of the main control judgment module is connected to the working condition acquisition module, and is used to calculate the comprehensive interference value according to the working condition parameters, and determine the current working condition according to the comprehensive interference value and a preset graded threshold; and output a corresponding switching control command based on the current working condition; the isolation switching module is connected in series in the floating buffer branch, and its control terminal is connected to the output terminal of the main control judgment module, and is used to dynamically adjust the conduction impedance of the floating buffer branch according to the switching control command, so as to change the potential coupling degree between the strong current ground plane and the weak current ground plane.

[0008] Optionally, calculating the comprehensive interference value based on the operating condition parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

[0009] Optionally, the current operating condition is determined based on the comprehensive interference value and a preset classification threshold; the corresponding switching control command output based on the current operating condition includes: when When the condition is determined to be low-interference, a conduction control command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the low-impedance conduction of the floating buffer branch based on the conduction control command, and the high-voltage ground plane and the low-voltage ground plane operate in an equivalent common ground; when When a strong interference condition is identified, a shutdown control command is output. Based on the switching control command, the conduction impedance of the floating buffer branch is dynamically adjusted, including controlling the floating buffer branch to completely disconnect based on the shutdown control command, thus achieving layered isolation between the high-voltage ground plane and the low-voltage ground plane. When the condition is determined to be a transitional operating condition, an impedance adjustment command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the floating buffer branch to work in an adjustable impedance state, so that the high-voltage ground plane and the low-voltage ground plane are in a floating buffer state with gradually changing potential.

[0010] Optionally, when the condition is determined to be a floating transition condition, or during the transition process between low interference condition and high interference condition, the main control judgment module performs potential correction.

[0011] Optionally, the main control judgment module performs potential correction by: determining the value of the adaptive adjustment coefficient α based on the real-time comprehensive interference value, and calculating the target floating real-time potential based on the adaptive adjustment coefficient α; the main control judgment module uses the target floating real-time potential as the control basis and outputs continuous impedance adjustment commands to the isolation switching module; the isolation switching module dynamically adjusts the conduction impedance of the floating buffer branch according to the impedance adjustment commands, changes the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane, so that the actual potential of the grounding reference follows the target floating real-time potential smoothly, and realizes a smooth transition during the working condition switching process, wherein the grounding reference is composed of the common potential state of the two ground planes connected by the floating buffer branch.

[0012] Optionally, the main control judgment module locks a judgment period of a preset duration after the working mode switch is completed, wherein the main control judgment module does not generate new switching control commands during the judgment locking period.

[0013] Optionally, the floating buffer branch is composed of a current-limiting resistor, a high-frequency buffer capacitor, a bidirectional Zener diode, and a controllable switching device connected in series. The current-limiting resistor is used to suppress the inrush current during switching; the high-frequency buffer capacitor is used to absorb circuit potential jitter; the bidirectional Zener diode is used to clamp the branch potential amplitude; and the controllable switching device is used to continuously adjust the branch conduction impedance.

[0014] Optionally, the high-voltage ground plane is laid on the bottom layer of the PCB, and the low-voltage ground plane is laid on the top layer of the PCB. The vertical projections of the two ground planes overlap and are physically insulated from each other.

[0015] According to a second aspect of the present invention, a method for adaptive isolation control of strong and weak current ground in a CT system is provided, comprising: real-time acquisition of operating parameters of the strong current circuit and the weak current circuit; calculation of a comprehensive interference value based on the operating parameters, and determination of the current operating condition based on the comprehensive interference value and a preset classification threshold; outputting a corresponding switching control command based on the current operating condition; and dynamically adjusting the conduction impedance of the suspended buffer branch according to the switching control command to change the potential coupling degree between the strong current ground plane and the weak current ground plane, wherein the strong current ground plane and the weak current ground plane of the suspended buffer branch are...

[0016] Optionally, calculating the real-time integrated disturbance value based on real-time operating parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

[0017] This embodiment describes an adaptive isolation circuit and control method for strong and weak ground in a CT system. Through a dynamic floating ground architecture, it achieves adaptive dynamic switching of the grounding isolation mode under different operating conditions. It maintains efficient operation with common ground under low interference conditions and automatically performs hierarchical isolation under strong interference conditions. It takes into account the circuit's anti-interference capability, response speed, low energy consumption, and long-term operational stability, thus solving the core pain points of traditional technologies. Attached Figure Description

[0018] 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.

[0019] Figure 1 This is an embodiment of the present invention for an adaptive isolation circuit for strong and weak ground in a CT system. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the invention described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] According to an embodiment of the present invention, an adaptive isolation circuit for strong and weak current ground in a CT system is provided, comprising a strong current circuit and a weak current control circuit. The circuit further comprises: a layered floating ground module, a working condition acquisition module, a main control judgment module, and an isolation switching module. The layered floating ground module includes a strong current ground plane and a weak current ground plane, which are independently arranged in layers, with a floating buffer branch between them. The working condition acquisition module is connected to both the strong current circuit and the weak current circuit, and is used to acquire circuit working condition parameters in real time. The input terminal of the main control judgment module is connected to the working condition acquisition module, and is used to calculate a comprehensive interference value based on the working condition parameters, and determine the current working condition based on the comprehensive interference value and a preset grading threshold; and output a corresponding switching control command based on the current working condition. The isolation switching module is connected in series in the floating buffer branch, and its control terminal is connected to the output terminal of the main control judgment module, and is used to dynamically adjust the conduction impedance of the floating buffer branch according to the switching control command to change the potential coupling degree between the strong current ground plane and the weak current ground plane.

[0024] In this embodiment, the PCB layer layout adopts a double-layer independent ground plane layout. The top layer is the low-voltage signal ground (AGND), and the bottom layer is the high-voltage power ground (PGND). The vertical projections of the two ground planes completely overlap and are physically insulated. The thickness of the interlayer insulation medium is set to 0.2mm to minimize native parasitic capacitance and coupling interference. The high-voltage and low-voltage grounds are not directly connected, and a floating buffer branch access point is reserved in the middle, which is completely different from the traditional single-point common ground and all-area hard isolation layout.

[0025] The layered floating ground module employs a layered, independent layout for high-voltage and low-voltage grounds, with a floating buffer connection branch between them. This ensures that the high-voltage and low-voltage grounds are neither completely disconnected nor in a fixed, bound state, forming a dynamically adjustable floating transition reference. The floating buffer branch is the only flexible and controllable connection path between the high-voltage and low-voltage ground planes, indirectly connecting the grounding systems of the high-voltage circuit and the low-voltage control circuit. One end of the branch is electrically connected to the high-voltage ground plane (the ground of the high-voltage circuit), and the other end is electrically connected to the low-voltage ground plane (the ground of the low-voltage control circuit). The on / off state and impedance changes of the branch only alter the coupling degree between the two sets of circuit grounding references.

[0026] Coupling specifically refers to conducted coupling between a high-voltage grounding system and a low-voltage grounding system, that is, the potential correlation and interference transmission relationship formed between the two grounding networks through the electrical connection path, which specifically includes: The degree of correlation of reference potentials: the higher the degree of coupling, the stronger the potential consistency between the high-voltage ground and the low-voltage ground, and the higher the uniformity of the reference references of the two circuits; the lower the degree of coupling, the stronger the potential independence of the two places, and the higher the separation of the reference references.

[0027] Interference conduction degree: The higher the coupling degree, the easier it is for interference such as voltage fluctuations, load changes, and high-frequency noise on the high-voltage side to enter the low-voltage circuit through the common ground conduction path; the lower the coupling degree, the greater the interference conduction impedance of the ground circuit, and the stronger the interference blocking effect.

[0028] In the regulation logic of this circuit, when the branch is conducting with low impedance, the coupling between the two places is the highest, and the circuit operates in an equivalent common ground manner, resulting in good signal synchronization and low loop loss. When the branch is completely disconnected, the coupling between the two places is the lowest, achieving physical layered isolation and providing the strongest interference blocking capability. When the branch is in a floating transition state with adjustable impedance, the coupling can be continuously and linearly adjusted, supporting smooth potential transition and disturbance-free switching.

[0029] As an optional implementation of this embodiment, the floating buffer branch is composed of a current-limiting resistor, a high-frequency buffer capacitor, a bidirectional Zener diode, and a controllable switching device connected in series. The current-limiting resistor is used to suppress the inrush current during switching; the high-frequency buffer capacitor is used to absorb circuit potential jitter; the bidirectional Zener diode is used to clamp the branch potential amplitude; and the controllable switching device is used to continuously adjust the branch conduction impedance.

[0030] The floating buffer branch consists of a high-precision current-limiting resistor, a high-frequency buffer capacitor, a bidirectional Zener diode, and a high-speed MOS controllable switch connected in series, forming a dynamically adjustable flexible connection channel. Specifically: the current-limiting resistor is 100Ω to limit the inrush current during switching; the buffer capacitor is 100nF to absorb high-frequency potential fluctuations; the bidirectional Zener diode has a regulated voltage of 3.3V to match the operating voltage of the low-voltage chip; and the MOS switch has a response time of ≤100ns, achieving millisecond-level rapid switching. This branch can achieve three states—"fully on," "impedance adjustable," and "fully off"—based on control signals, supporting the landing of the floating dynamic model.

[0031] The operating condition acquisition module adopts a multi-parameter synchronous sampling architecture. Voltage sampling uses a precision voltage divider circuit (100:1 ratio), current sampling uses a high-precision shunt resistor (0.01Ω) paired with an operational amplifier for differential amplification, and electromagnetic interference and noise sampling uses a high-frequency detection circuit that can capture high-frequency interference signals from 10kHz to 1MHz. All sampled signals are converted into digital signals by an ADC analog-to-digital converter (12-bit precision), with a fixed sampling frequency of 1kHz to ensure data real-time performance and accuracy.

[0032] The operating condition acquisition module interfaces with both the high-voltage and low-voltage circuits, and is equipped with voltage sampling units, current sampling units, electromagnetic interference detection units, and noise detection units. It collects real-time data on grid voltage fluctuations, load current changes, spatial electromagnetic interference intensity, and high-frequency noise parameters of the circuit, converting all analog parameters into digital signals for transmission to the main control MCU module. The main control MCU module pre-stores operating condition judgment thresholds, including upper limits for normal operating conditions and thresholds for strong interference conditions. It receives the collected data in real-time, performs calculations and comparisons, and outputs high / low level control signals to drive the isolation switching module.

[0033] The operating condition acquisition module collects circuit operating parameters in real time, including electromagnetic interference intensity, grid voltage fluctuation amplitude, load current surge parameters, and high-frequency noise amplitude, and converts analog signals into digital signals for transmission to the main control judgment module. The main control judgment module has built-in interference threshold judgment logic, preset standard operating condition thresholds and strong interference operating condition thresholds, performs millisecond-level calculations and comparisons on the real-time acquired operating condition data, and outputs corresponding switching control commands. The isolation switching module receives the quantization commands from the main control judgment module, dynamically adjusts the conduction impedance and isolation state of the layered floating ground module, and achieves adaptive, disturbance-free switching of operating conditions by combining the potential balance correction formula.

[0034] The main control module has built-in interference threshold determination logic, preset standard operating condition thresholds and strong interference operating condition thresholds, performs millisecond-level calculations and comparisons on the real-time acquired operating condition data, and outputs corresponding switching control commands. It can use an STM32F103 series main control MCU, with built-in Flash storage for calibration threshold parameters, allowing users to modify them according to different equipment scenarios. The threshold and weighting coefficients are highly versatile. The MCU has a built-in hardware timer, enabling precise millisecond-level closed-loop calculations with no program delay errors.

[0035] The isolation switching module receives quantization commands from the main control judgment module, dynamically adjusts the conduction impedance and isolation state of the layered floating ground module, and achieves adaptive and disturbance-free switching of operating conditions by combining the potential balance correction formula.

[0036] As an optional implementation of this embodiment, the step of calculating the comprehensive interference value based on the operating condition parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

[0037] In this optional implementation, to avoid misjudgment based on a single parameter, a multi-dimensional comprehensive interference assessment model is constructed to accurately determine the interference level of the current operating condition: In the formula: This represents the real-time integrated interference value. The voltage fluctuation amplitude (V) on the high-voltage side. The difference in load current sudden change (A); The electromagnetic interference field strength in space (V / m); The effective value of high-frequency noise in the loop (mV); The weighting coefficients for each interference component are calibrated according to the device application scenario. The default values ​​for medical and industrial scenarios are [0.35, 0.25, 0.2, 0.2].

[0038] As an optional implementation of this embodiment, the current operating condition is determined based on the comprehensive interference value and a preset grading threshold; the corresponding switching control command output based on the current operating condition includes: when When the condition is determined to be low-interference, a conduction control command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the low-impedance conduction of the floating buffer branch based on the conduction control command, and the high-voltage ground plane and the low-voltage ground plane operate in an equivalent common ground; when When a strong interference condition is identified, a shutdown control command is output. Based on the switching control command, the conduction impedance of the floating buffer branch is dynamically adjusted, including controlling the floating buffer branch to completely disconnect based on the shutdown control command, thus achieving layered isolation between the high-voltage ground plane and the low-voltage ground plane. When the condition is determined to be a transitional operating condition, an impedance adjustment command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the floating buffer branch to work in an adjustable impedance state, so that the high-voltage ground plane and the low-voltage ground plane are in a floating buffer state with gradually changing potential.

[0039] In this optional implementation, the MCU substitutes the values ​​into the comprehensive interference intensity formula to calculate... The current operating condition is classified into three levels based on a threshold determination formula: low interference, high interference, and floating transition. Precise mode switching is achieved through graded thresholds, preventing frequent jitter-induced false switching. Low interference grounding determination: Strong interference isolation determination: ; Suspension transition buffer determination: , The lower limit of the low interference threshold. As the upper limit of the strong interference threshold, dual threshold hysteresis control can effectively avoid frequent switching oscillations of the circuit under critical operating conditions.

[0040] For example, in a civilian low-interference scenario: Medical and industrial standard scenarios: Complex and highly interference-prone industrial control scenarios: It can be flexibly adapted to the actual electromagnetic environment.

[0041] As an optional implementation of this embodiment, when the condition is determined to be a floating transition condition, or during the transition process between low interference condition and strong interference condition, the main control judgment module performs potential correction.

[0042] As an optional implementation of this embodiment, the main control judgment module performs potential correction by: determining the value of the adaptive adjustment coefficient α based on the real-time comprehensive interference value, and calculating the target floating real-time potential based on the adaptive adjustment coefficient α; the main control judgment module outputs continuous impedance adjustment commands to the isolation switching module based on the target floating real-time potential; the isolation switching module dynamically adjusts the conduction impedance of the floating buffer branch according to the impedance adjustment commands, thereby changing the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane.

[0043] In the above-mentioned optional implementation methods, to solve the problem of potential jump during switching and achieve bumpless switching, a dynamic potential correction model is adopted: In the formula: This serves as a real-time reference potential for the floating ground. This is the static reference potential for weak current ground; This represents the real-time potential of the high-voltage ground. The adaptive adjustment coefficient decreases linearly from 1 to 0 as the interference intensity increases, achieving a smooth transition from common ground to isolation.

[0044] By changing the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane, the actual potential of the grounding reference can smoothly follow the real-time floating potential of the target, thus achieving a smooth transition during the switching of operating conditions. The grounding reference is composed of the common potential state of the two ground planes connected by a floating buffer branch.

[0045] As an optional implementation of this embodiment, the main control judgment module locks a judgment period of a preset duration after the working mode switch is completed. During the judgment locking period, the main control judgment module does not generate new switching control commands.

[0046] In this optional implementation, a hysteresis buffer mechanism is added to lock the 20ms judgment period after the operating condition is switched, so as to avoid frequent switching caused by instantaneous fluctuations in interference and improve system stability.

[0047] The method in this embodiment is applied as follows: Step 1: Initialization Calibration. After the device is powered on, the MCU automatically completes parameter calibration, reads the preset interference weight coefficient, dual threshold parameters, and potential adjustment coefficient range, initializes the ADC sampling module and switching drive module, and establishes a standard floating ground potential reference.

[0048] Step 2: Synchronous sampling of all parameters. The operating condition acquisition module synchronously acquires four types of parameters at a frequency of 1kHz: voltage fluctuation, current change, electromagnetic field strength, and high-frequency noise, filters sampling noise, and outputs stable and valid data.

[0049] Step 3: Quantization and Operating Condition Determination. The MCU is quantized using the comprehensive interference intensity formula. Based on the threshold determination formula, the current operating condition level is divided into: low interference condition, strong interference condition, and floating transition condition.

[0050] Step 4: Precise control by mode.

[0051] ① Low-interference operating conditions ( ): The MOS switch is fully turned on, the floating buffer branch is connected with low impedance, and the strong and weak ground references are unified through the potential correction formula, so as to operate in an equivalent common ground, reduce losses and improve response speed. ② Strong interference conditions ( ): The MOS switch is quickly disconnected, the floating branch is completely shut off, and the strong and weak electrical grounds are physically isolated, completely blocking ground loop interference coupling. ③ Transitional operating condition ( Adjusting the on-resistance of the MOS switch to dynamically change The coefficient allows for a smooth transition of the suspended ground potential, achieving gradual buffering and adjustment, and avoiding critical oscillations in operating conditions.

[0052] Step 5: Hysteresis Anti-jitter Control. After switching operating conditions, a 20ms decision period is locked to avoid frequent switching caused by instantaneous fluctuations in interference, thereby improving system stability.

[0053] Step 6: Closed-loop continuous monitoring. Continuous cyclic sampling, calculation, and adjustment are performed to achieve adaptive closed-loop control under all operating conditions.

[0054] After step 1 above, step 2 can also be used: the main control MCU compares the collected parameters with the preset threshold in real time to determine the working condition; Step 3: If all collected parameters are below the strong interference threshold, it is determined to be a normal low interference condition. The main control outputs a conduction control signal to control the floating buffer branch to conduct slightly. The strong and weak electrical grounds are equivalent to a common ground, and the circuit operates in a high-efficiency, low-loss, and high-response state. Step 4: If any interference parameter exceeds the preset threshold, it is determined to be a strong interference complex working condition. The main control outputs a disconnection control signal to cut off the floating buffer branch, and the strong and weak electrical grounds are completely isolated in layers to block the ground loop interference coupling. Step 5: When the interference disappears and the operating conditions return to stability, the main controller automatically resets the control signal, and the circuit switches back to the common ground operation mode to complete the adaptive closed-loop control.

[0055] This embodiment of bumpless handover relies on a collaborative solution of potential balance correction and hardware buffer structure, which differs from traditional switch-type hard handover. At the moment of mode switching, energy is stored in a buffer capacitor, current is limited by a current-limiting resistor, and an adjustment coefficient is used... Linear gradient allows for stepless changes in the floating ground potential, with the rate of potential change controlled to ≤10mV / ms, completely avoiding signal jitter, data drift, and chip voltage surges. Simultaneously, the impedance gradient adjustment mechanism under transitional operating conditions enables seamless transition between common ground and isolated states, ensuring continuous and stable operation of the equipment throughout the entire process, without operational interruptions or functional failure intervals.

[0056] This embodiment is a layered floating adaptive isolation circuit for strong and weak electrical grounds. Its core lies in establishing a quantifiable and closed-loop controllable dynamic floating ground mathematical model and hardware topology. The overall architecture includes: a layered floating ground hardware topology, a real-time operating condition detection and quantization unit, a threshold calculation intelligent judgment unit, and a disturbance-free adaptive switching execution unit. It completely abandons the traditional binary static fixed mode of permanent isolation and permanent common ground. Through electromagnetic interference quantification formulas, potential balance formulas, and switching criterion formulas, it constructs dynamic adjustment logic, allowing the isolation degree of strong and weak electrical grounds to linearly and adaptively adjust with the interference intensity, achieving refined control of "efficient common grounding for weak interference, complete isolation for strong interference, and smooth floating during transitional operating conditions."

[0057] Through a dynamic floating ground architecture, the grounding isolation mode is adaptively and dynamically switched under different operating conditions. It maintains efficient operation under low interference conditions and automatically isolates layers under strong interference conditions. It takes into account the circuit's anti-interference capability, response speed, low energy consumption and long-term operational stability, solves the core pain points of traditional technologies, overcomes the technical defects of existing strong and weak current isolation circuits such as static fixation, poor adaptability and performance contradictions, and improves CT performance.

[0058] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0059] According to an embodiment of the present invention, an adaptive isolation control method for strong and weak current ground in a CT system is also provided, comprising: real-time acquisition of operating parameters of the strong current circuit and the weak current circuit; calculation of a comprehensive interference value based on the operating parameters, and determination of the current operating condition based on the comprehensive interference value and a preset classification threshold; outputting a corresponding switching control command based on the current operating condition; and dynamically adjusting the conduction impedance of the suspended buffer branch according to the switching control command to change the potential coupling degree between the strong current ground plane and the weak current ground plane, wherein the strong current ground plane and the weak current ground plane of the suspended buffer branch are...

[0060] As an optional implementation method in this embodiment, calculating the real-time integrated interference value based on real-time operating parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A strong and weak current adaptive isolation circuit for a CT system, characterized in that, This includes a layered floating ground module, a working condition acquisition module, a main control judgment module, and an isolation switching module; The layered suspended ground module includes a high-voltage ground plane and a low-voltage ground plane. The high-voltage ground plane and the low-voltage ground plane are arranged independently in layers, and a suspended buffer branch is set between them. The operating condition acquisition module is connected to the high-voltage circuit and the low-voltage circuit in the CT equipment grounding system, respectively, and is used to acquire the operating condition parameters of the high-voltage circuit and the low-voltage circuit in real time. The input terminal of the main control judgment module is connected to the operating condition acquisition module, and is used to calculate the comprehensive interference value according to the operating condition parameters, and determine the current operating condition based on the comprehensive interference value and the preset grade threshold; and output the corresponding switching control command based on the current operating condition. The isolation switching module is connected in series in the floating buffer branch, and its control terminal is connected to the output terminal of the main control judgment module. It is used to dynamically adjust the conduction impedance of the floating buffer branch according to the switching control command, so as to change the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane.

2. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 1, characterized in that, The calculation of the comprehensive interference value based on the operating condition parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

3. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 2, characterized in that, The current operating condition is determined based on the comprehensive interference value and the preset classification threshold; the corresponding switching control commands output based on the current operating condition include: when When the condition is determined to be a low-interference operating condition, a conduction control command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the low-impedance conduction of the floating buffer branch based on the conduction control command, and the high-voltage ground plane and the low-voltage ground plane are equivalently co-grounded. when When the condition is determined to be a strong interference condition, a shutdown control command is output. The conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the floating buffer branch to be completely disconnected based on the shutdown control command, so that the high-voltage ground plane and the low-voltage ground plane are isolated in layers. when When the condition is determined to be a transitional operating condition, an impedance adjustment command is output; the conduction impedance of the floating buffer branch is dynamically adjusted according to the switching control command, including controlling the floating buffer branch to work in an adjustable impedance state, so that the high-voltage ground plane and the low-voltage ground plane are in a floating buffer state with gradually changing potential.

4. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 3, characterized in that, When the system is determined to be in a floating transition condition, or during the transition between low-interference and high-interference conditions, the main control judgment module performs potential correction.

5. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 4, characterized in that, The main control judgment module performs potential correction including: The value of the adaptive adjustment coefficient α is determined based on the real-time comprehensive interference value, and the real-time floating potential of the target is calculated based on the adaptive adjustment coefficient α. The main control judgment module uses the target floating real-time potential as the control basis and outputs continuous impedance adjustment commands to the isolation switching module. The isolation switching module dynamically adjusts the conduction impedance of the floating buffer branch according to the impedance adjustment commands, changes the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane, so that the actual potential of the grounding reference follows the target floating real-time potential smoothly, and realizes the smooth transition of the working condition switching process. The grounding reference is composed of the common potential state of the two ground planes connected by the floating buffer branch.

6. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 1, characterized in that, After the operating mode switch is completed, the main control judgment module locks a judgment period of a preset duration. During the judgment locking period, the main control judgment module does not generate new switching control commands.

7. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 1, characterized in that, The floating buffer branch is composed of a current-limiting resistor, a high-frequency buffer capacitor, a bidirectional Zener diode, and a controllable switching device connected in series. The current-limiting resistor is used to suppress the inrush current during switching; the high-frequency buffer capacitor is used to absorb potential jitter in the circuit; the bidirectional Zener diode is used to clamp the potential amplitude of the branch; and the controllable switching device is used to continuously adjust the on-resistance of the branch.

8. The adaptive isolation circuit for strong and weak current ground in a CT system according to claim 1, characterized in that, The high-voltage ground plane is laid on the bottom layer of the PCB, and the low-voltage ground plane is laid on the top layer of the PCB. The vertical projections of the two ground planes overlap and are physically insulated from each other.

9. A method for adaptive isolation control of strong and weak electrical ground in a CT system, characterized in that, include: Real-time acquisition of operating parameters of high-voltage and low-voltage circuits; The comprehensive interference value is calculated based on the operating parameters, and the current operating condition is determined based on the comprehensive interference value and the preset classification threshold; the corresponding switching control command is output based on the current operating condition. The on-resistance of the floating buffer branch is dynamically adjusted according to the switching control command to change the potential coupling degree between the high-voltage ground plane and the low-voltage ground plane.

10. The adaptive isolation control method for strong and weak current ground in a CT system according to claim 9, characterized in that, The calculation of real-time comprehensive interference value based on real-time operating parameters includes: based on Calculate the overall interference value, where, This represents the real-time integrated interference value. This refers to the amplitude of voltage fluctuation on the high-voltage side. This represents the difference in load current sudden change. This refers to the electromagnetic interference field strength in space. This represents the effective value of high-frequency noise in the loop. The weighting coefficients for each interference component are calibrated according to the application scenario of the equipment.

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