A method of ray tube training and power generator

Abstract

The present application belongs to the technical field of X-ray tube control method, and particularly provides a kind of ray tube training machine method and power generator. Wherein a kind of ray tube training machine method, specific process includes obtaining last time X-ray tube working date and X-ray tube type;Confirm the long X-ray tube preheating time, set the starting time function and end time function of radiation preheating;Confirm the basic parameters of X-ray tube;Deduce the final preheating power of X-ray tube;Draw curve;Execute ray tube training machine operation.A kind of power generator, including main circuit and control circuit, control circuit is used to control main circuit, control circuit is based on PID control theory operation.This scheme adopts the control method of tube voltage and tube current using PID control principle, forms double closed loop feedback control system, that is, prevent accidental overshoot and prevent control system oscillation;According to the intersection area of curve, get training machine power supply curve, and according to the curve smooth and continuous implementation power supply.

Description

Technical Field

[0001] This invention belongs to the technical field of X-ray tube control methods, and specifically provides a method for X-ray tube training machine and a power generator. Background Technology

[0002] Training machine refers to the pre-start operation of the entire X-ray tube system. (Refer to...) Figure 4 U is the tube voltage, U a For filament voltage, I a I is the filament current, I is the tube current, and W is the tube current. in For coolant to flow in, W out As the coolant flows out, the X-ray tube generates X-rays through ionization, also known as ionizing radiation. This means that the filament ionizes electrons, which are accelerated to the electrode plate, reflected by the electrode plate, and then reflected through the focal point to the lead hole (focal point) and emitted as X-rays.

[0003] X-ray tube-based imaging equipment such as CT scanners and DR machines require a restart program after shutdown to ensure that the X-ray tube is in optimal condition during actual imaging operations.

[0004] Most power generators on the market consist of a main circuit (including a rectifier unit, filter unit, inverter unit, transformer unit, and voltage doubler rectifier unit; the input circuit is sequentially connected to the rectifier unit, filter unit, inverter unit, transformer unit, and voltage doubler rectifier unit; the voltage doubler rectifier unit is electrically connected to the X-ray tube via the output circuit), a control circuit, and software. The control circuit, lacking closed-loop control for tube current control, is prone to overshooting, causing equipment damage. Furthermore, due to software and design limitations, it can only use a segmented method to set the power curve. (Refer to...) Figure 5 Within a certain power range, the same output current is used for power supply, but the X-ray tube cannot reach its optimal operating power within that range under that current. The training control logic of this type of power generator also has flaws. Once the training function is started, it cannot be paused (suddenly pausing the training operation would cause the X-ray tube to lose power, potentially posing a safety hazard). Furthermore, there are no restrictions on mandatory training for prolonged X-ray tube shutdowns (generally limited to 72 hours; shutdowns exceeding 72 hours are considered long-term shutdowns, shutdowns less than 72 hours are considered short-term shutdowns, and shutdowns less than 8 hours do not require training). This leads to a high failure rate in the imaging equipment. Summary of the Invention

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for a radiation tube training machine, the specific process of which is as follows: Step 1: Obtain the date and time of the last X-ray tube operation and the type of the X-ray tube; Step 2: Determine the preheating time t of the X-ray tube. Let the start time of the radiation preheating be T1 and the end time be T2, where T2 = T1 + t. Step 3: Confirm the basic parameters of the X-ray tube; Step 4: Derive the final preheating power of the X-ray tube; Step 5: Plot the tube voltage of the X-ray tube as a function of time; Step 6: Plot the curve of tube current changing over time in the X-ray tube; Step 7: Plot the tube power curve of the X-ray tube; P=U·I; Where P is the preheating tube power, U is the preheating tube voltage, and I is the preheating tube current; Step 8: Operate the X-ray tube training machine; Based on the above curve dynamics, the power supply parameters of the power generator are adjusted in real time until the training time reaches time T2, thus completing the training.

[0006] Furthermore, in step one, recording the date and time of the last operation of the X-ray tube is a basic function of the X-ray tube control system. The X-ray tube type refers to the model of the X-ray tube currently installed on the equipment. X-ray tubes used in the market are generally standardized devices, and the basic parameters of the X-ray tube can be obtained by looking up a table.

[0007] Furthermore, in step three, the basic parameters specifically include the maximum preheating tube voltage U. max Maximum preheating tube current I max Maximum preheating power P max Preheating start tube voltage U s and preheating start tube current I s .

[0008] Furthermore, in step four, the final preheating power of the X-ray tube is P. over ; P over =P MAX ·K p ; In the formula, K p This represents the preheating power percentage, with a theoretical value between 0% and 100%. The specific power required by the power generator will be calculated based on the radiation intensity needed for this filming mission. (K) p =Used power / Maximum power of power generator.

[0009] Furthermore, in step five, according to the formula: U=U s ·log 10 (10P) t +a); P t =t i / t; In the formula, U is the preheating tube voltage, U s P is the preheating starting tube voltage. t The preheating time and the X-ray tube preheating time are the proportions of the preheating timing time and the X-ray tube preheating time, respectively. 'a' is a constant describing the leading amount of the preheating voltage rise (obtained from a table), and 't' is the value of the preheating timing time. i T is the time interval of a single sampling period. C The current time T for preheating the X-ray tube C =T1+t i ; With a fixed sampling period, take multiple different T values. C By substituting the numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube voltage can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube voltage over time.

[0010] Furthermore, in step six, the tube voltage U... max The current curve of the ray tube is divided into two parts at the dividing point; When the tube voltage rises to U max Previously, it was obtained according to the following formula: I=I s ; When the tube voltage rises to U max Then, it is obtained according to the following formula: I=t i ·K+I s ; K=P over / U over / t; In the formula, I is the preheating tube current, I s Preheating start tube current; With a fixed sampling period, take multiple different t values. i By substituting numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube current can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube current over time.

[0011] A power generator includes a main circuit and a control circuit, wherein the control circuit is used to control the main circuit; The main circuit includes a rectifier unit, a filter unit, an inverter unit, a transformer unit, and a voltage doubler rectifier unit. The input circuit is connected to the rectifier unit, filter unit, inverter unit, transformer unit, and voltage doubler rectifier unit in sequence. The voltage doubler rectifier unit is electrically connected to the X-ray tube via the output circuit. The control loop operates based on PID control theory and is used to control the main loop.

[0012] Furthermore, the control loop has a built-in independent timing unit, which is directly associated with the main loop and has a preset forced training duration value.

[0013] The beneficial effects of using this invention are: This solution employs the PID control principle in the control methods of tube voltage and tube current to form a dual closed-loop feedback control system. This system prevents unexpected overshoot and ensures equipment safety, while also preventing control system oscillations that could cause X-ray dose fluctuations. It also provides the hardware foundation for the training machine pause function and forced training function. Simultaneously, the data curves of tube current and tube voltage during the start-up process of the X-ray tube and the data curves of current and voltage at the power supply end are calculated and plotted. The power supply curve of the training machine is obtained based on the intersection area of ​​the curves, and the power supply is implemented smoothly and continuously according to the curve, so that the power supply parameters at any time during the training process match the current optimal working power of the X-ray tube, thereby optimizing the rationality of the training process. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the main circuit of the power generator of the present invention; Figure 2 This is a schematic diagram of the voltage detection and control circuit of the power generator of the present invention; Figure 3 This is a schematic diagram of the current detection and control circuit of the power generator of the present invention; Figure 4 This is a schematic diagram illustrating the operating principle of a ray tube in the background art; Figure 5 The background section shows the stepped power supply curve of the existing training machine method in the background art. Figure 6 This is a power supply curve diagram for the training method of the present invention; Detailed Implementation

[0015] The present invention will now be described in detail with reference to the accompanying drawings.

[0016] A method for a X-ray tube training machine uses a power generator capable of linearly outputting a stable voltage as the power supply module for the training machine. The specific process is as follows: Step 1: Obtain the date and time of the last X-ray tube operation and the type of the X-ray tube; Specifically, recording the date and time of the last operation of the X-ray tube is a basic function of the X-ray tube control system. The X-ray tube type refers to the model of the X-ray tube currently installed on the equipment. X-ray tubes used in the market are generally standardized devices, and the basic parameters of the X-ray tube can be obtained by looking up a table.

[0017] Step 2: Determine the preheating time t of the X-ray tube. Let the start time of the radiation preheating be T1 and the end time be T2, where T2 = T1 + t. Step 3: Confirm the basic parameters of the X-ray tube, specifically including the maximum preheating tube voltage U. max Maximum preheating tube current I max Maximum preheating power P maxPreheating start tube voltage U s and preheating start tube current I s ; Step 4: Derive the final preheating power P of the X-ray tube over ; P over =P MAX ·K p ; In the formula, K p This represents the preheating power percentage, with a theoretical value between 0% and 100%. The specific power required by the power generator will be calculated based on the radiation intensity needed for this filming mission. (K) p =Used power / Maximum power of power generator.

[0018] Step 5: Plot the tube voltage of the X-ray tube as a function of time; Specifically, according to the formula: U=U s ·log 10 (10P) t +a); P t =t i / t; In the formula, U is the preheating tube voltage, U s P is the preheating starting tube voltage. t The preheating time and the X-ray tube preheating time are the proportions of the preheating timing time and the X-ray tube preheating time, respectively. 'a' is a constant describing the leading amount of the preheating voltage rise (obtained from a table), and 't' is the value of the preheating timing time. i T is the time interval of a single sampling period. C The current time T for preheating the X-ray tube C =T1+t i ; With a fixed sampling period, take multiple different T values. C By substituting the numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube voltage can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube voltage over time.

[0019] Step 6: Plot the curve of tube current changing over time in the X-ray tube; With tube voltage U max The current curve of the ray tube is divided into two parts at the dividing point; When the tube voltage rises to U max Previously, it was obtained according to the following formula: I=I s ; When the tube voltage rises to U max Then, it is obtained according to the following formula: I=t i ·K+I s ; K=P over / U over / t; In the formula, I is the preheating tube current, I s Preheating start tube current; With a fixed sampling period, take multiple different t values. i By substituting numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube current can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube current over time.

[0020] Step 7: Plot the tube power curve of the X-ray tube; P=U·I; Where P is the preheating tube power, U is the preheating tube voltage, and I is the preheating tube current.

[0021] Step 8: Operate the X-ray tube training machine; Based on the above curve dynamics, the power supply parameters of the power generator are adjusted in real time until the training time reaches time T2, thus completing the training.

[0022] Reference Figure 6 The training curve is continuous and smooth, and the power supply data at any point in time matches the current optimal operating power of the X-ray tube.

[0023] Reference Figures 1-3 A power generator includes a main circuit and a control circuit, wherein the control circuit is used to control the main circuit; The main circuit includes a rectifier unit, a filter unit, an inverter unit, a transformer unit, and a voltage doubler rectifier unit. The input circuit is connected to the rectifier unit, filter unit, inverter unit, transformer unit, and voltage doubler rectifier unit in sequence. The voltage doubler rectifier unit is electrically connected to the X-ray tube via the output circuit. The rectifier and filter unit adopts a bridge rectifier circuit and installs a filter capacitor in the circuit. After the current is input to the rectifier and filter unit, it is first rectified and then filtered by the capacitor to obtain a smooth DC voltage. The inverter unit can convert the DC voltage output from the rectifier and filter unit into a high-frequency square wave and output it to the next unit; The transformer unit uses a high-voltage transformer, which consists of a primary coil and a secondary coil. The leakage inductance of the high-voltage transformer and the secondary current resonate together in the primary coil of the transformer, and the resonant frequency is synchronized with the inverter frequency, which reduces circuit losses and electromagnetic interference. The voltage multiplier rectifier unit is connected to the X-ray tube via a high-voltage cable. The current supplied by the upper unit is amplified by the voltage multiplier rectifier unit and then transmitted to the X-ray tube via the high-voltage cable.

[0024] The control loop operates based on PID control theory and is used to control the main loop. The control loop has a built-in independent timing unit, which is directly associated with the main loop and has a preset forced training duration value. The control loop includes a voltage measurement and control unit and a current measurement and control unit. The specific control principle is as follows: The differential equation for PID control is: ; In the formula: y(t) represents the output voltage of the tube; n(t) is the given value of the tube voltage; e(t) is the control input, i.e., the deviation: e(t) = n(t) - y(t) is the deviation between the controlled variable and the given value; u(t) is the control output; K p This is the proportionality coefficient; T i The integral time constant; T d is the differential time constant.

[0025] The above content is only a preferred embodiment of the present invention. For those skilled in the art, many changes can be made in the specific implementation and application scope based on the concept of the present invention. As long as these changes do not depart from the concept of the present invention, they all fall within the protection scope of the present invention.

Claims

1. A method for using a radiation tube training machine, characterized in that: The specific process is as follows: Step 1: Obtain the date and time of the last X-ray tube operation and the type of the X-ray tube; Step 2: Determine the preheating time t of the X-ray tube. Let the start time of the radiation preheating be T1 and the end time be T2, where T2 = T1 + t. Step 3: Confirm the basic parameters of the X-ray tube; Step 4: Derive the final preheating power of the X-ray tube; In step four, the final preheating power of the X-ray tube is P. over ; P over =P MAX ·K p ; In the formula, K p This represents the preheating power percentage, with a theoretical value between 0% and 100%. The specific power required by the power generator will be calculated based on the radiation intensity needed for this filming mission. (K) p =Used power / Maximum power of power generator; Step 5: Plot the tube voltage of the X-ray tube as a function of time; In step five, according to the formula: U=U s ·log 10 (10P t +a); P t =t i / t; In the formula, U is the preheating tube voltage, U s P is the preheating starting tube voltage. t The preheating time is the ratio of the preheating time to the X-ray tube preheating time, 'a' is a constant describing the lead of the preheating voltage rise trend, and 't' is a constant representing the ratio of the preheating timing time to the X-ray tube preheating time. i T is the time interval of a single sampling period. C The current time T for preheating the X-ray tube C =T1+t i ; With a fixed sampling period, take multiple different T values. C By substituting the numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube voltage can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube voltage over time. Step 6: Plot the curve of tube current changing over time in the X-ray tube; In step six, the tube voltage U max The current curve of the X-ray tube is divided into two parts at the dividing point; When the tube voltage rises to U max Previously, it was obtained according to the following formula: I=I s ; When the tube voltage rises to U max Then, it is obtained according to the following formula: I=t i ·K+I s ; K=P over / U over / t; In the formula, I is the preheating tube current, I s Preheating start tube current; With a fixed sampling period, take multiple different t values. i By substituting the numerical values ​​into the formula, multiple discrete points expressing the relationship between time and tube current can be obtained. Connecting these discrete points with a smooth curve forms a curve showing the change of tube current over time. Step 7: Plot the tube power curve of the X-ray tube; P=U·I; Where P is the preheating tube power, U is the preheating tube voltage, and I is the preheating tube current; Step 8: Operate the X-ray tube training machine; Based on the above curve dynamics, the power supply parameters of the power generator are adjusted in real time until the training time reaches time T2, thus completing the training.

2. The method for a radiation tube training machine according to claim 1, characterized in that: In step one, recording the date and time of the last X-ray tube operation is a basic function of the X-ray tube control system. The X-ray tube type refers to the model of the X-ray tube currently installed on the equipment. X-ray tubes used in the market are generally standardized devices, and the basic parameters of the X-ray tube can be obtained by looking up a table.

3. The method for a radiation tube training machine according to claim 1, characterized in that: In step three, the basic parameters specifically include the maximum preheating tube voltage U. max Maximum preheating tube current I max Maximum preheating power P max Preheating start tube voltage U s and preheating start tube current I s .

4. The X-ray tube training machine method as described in claim 1, characterized in that: The power generator includes a main circuit and a control circuit, and the control circuit is used to control the main circuit. The main circuit includes a rectifier unit, a filter unit, an inverter unit, a transformer unit, and a voltage doubler rectifier unit. The input circuit is connected to the rectifier unit, filter unit, inverter unit, transformer unit, and voltage doubler rectifier unit in sequence. The voltage doubler rectifier unit is electrically connected to the X-ray tube via the output circuit. The control loop operates based on PID control theory and is used to control the main loop.

5. The X-ray tube training machine method according to claim 4, characterized in that: The control loop has a built-in independent timing unit, which is directly connected to the main loop and has a preset forced training duration value.

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