An electric power generator and an automatic detection circuit thereof

Abstract

The present disclosure relates to an automatic detection circuit of an electric energy generator, an input end of the electric energy generator being connected to a power grid, an output end being connected to an electric component, the automatic detection circuit comprising: a discharge circuit having a switch and a discharge resistor connected in series, the discharge resistor discharging electric energy generated by the electric energy generator; a control circuit controlling opening and closing of the switch; wherein, before the electric energy generator supplies power to the electric component, the control circuit controls the switch to be closed for a first time, and discharges through the discharge resistor. According to the present disclosure, an electric energy generator and an automatic detection circuit thereof are provided, and the electric energy generated by the electric energy generator can be detected.

Description

Technical Field

[0001] This disclosure relates to the field of circuits, and more specifically, to an electric power generator and its detection circuit. Background Technology

[0002] High-power power generators are widely used in modern society, and their power supply capacity is often known. In addition, these power generators are connected to the power grid, and their power supply capacity may also be affected by the grid's power supply capacity. In this case, whether the power they can provide meets the actual needs is also a concern in the industry. Summary of the Invention

[0003] In view of this, the present disclosure provides an electric power generator and its detection circuit.

[0004] According to an exemplary embodiment of this disclosure, an automatic detection circuit for an energy generator is provided, wherein the input terminal of the energy generator is connected to the power grid and the output terminal is connected to an electrical component. The automatic detection circuit comprises: a discharge circuit having a switch and a discharge resistor connected in series, the discharge resistor discharging the electrical energy generated by the energy generator; and a control circuit controlling the opening and closing of the switch; wherein, before the energy generator supplies power to the electrical component, the control circuit controls the switch to close and remain closed for a first time, discharging through the discharge resistor.

[0005] According to an exemplary embodiment of this disclosure, after the power generator supplies power to the electrical component, the control circuit controls the switch to close and continue for a second time to discharge through the discharge resistor.

[0006] According to an exemplary embodiment of this disclosure, the power grid is alternating current (AC), the power generator further includes a rectifier and filter circuit for rectifying and filtering the AC power of the power grid, and the automatic detection circuit further includes: a bus voltage detection circuit for acquiring the bus voltage value output by the rectifier and filter circuit; and a discharge current detection circuit for acquiring the discharge resistance current value of the discharge process at a first time; and the first time is greater than or equal to one cycle of the rectified waveform.

[0007] According to an exemplary embodiment of this disclosure, the discharge current detection circuit is implemented by measuring the voltage across the discharge resistor.

[0008] According to an exemplary embodiment of the present disclosure, a power generator is provided, wherein the input end of the power generator is connected to the alternating current of the power grid, and the output end is connected to an electrical component, characterized in that the power generator includes: a rectifier and filter circuit for rectifying and filtering the alternating current of the power grid; and the automatic detection circuit described in any of the preceding claims.

[0009] According to an exemplary embodiment of this disclosure, a power generator is provided, wherein the input terminal of the power generator is connected to the alternating current of the power grid, and the output terminal is connected to an electrical component. The power generator comprises: a rectifier and filter circuit for rectifying and filtering the alternating current of the power grid; the aforementioned automatic detection circuit including a bus voltage detection circuit and a discharge current detection circuit; and a calculation unit for calculating the internal resistance of the power grid based on the bus voltage and the voltage across the discharge resistor.

[0010] According to an exemplary embodiment of this disclosure, before supplying power to the electrical component, the control circuit controls the switch of the discharge circuit to open, and the calculation unit reads the first voltage of the bus; then the control circuit controls the switch of the discharge circuit to close, and the calculation unit reads the second voltage of the bus and the third voltage across the discharge resistor, and calculates the internal resistance of the power grid based at least on the first voltage, the second voltage, the third voltage and the resistance value of the discharge resistor.

[0011] According to an exemplary embodiment of this disclosure, the calculation unit further calculates the maximum power consumption of the electrical component based on the internal resistance of the power grid.

[0012] According to an exemplary embodiment of this disclosure, calculating the maximum power consumption of the electrical component includes: calculating the maximum output current using the power supply under bias tolerance value and the internal resistance of the power grid; and calculating the maximum power consumption of the electrical component using the maximum output current and the rated power supply voltage of the electrical component.

[0013] According to an exemplary embodiment of this disclosure, the electrical component is an X-ray tube assembly, and the power generator further includes a filament heating circuit.

[0014] The power generator and its automatic detection circuit provided in this disclosure can be used to detect the output status of the power generator. Attached Figure Description

[0015] The preferred embodiments of this disclosure will now be described in detail with reference to the accompanying drawings, which will make the above and other features and advantages of this disclosure more apparent to those skilled in the art. In the drawings:

[0016] Figure 1 The present disclosure provides an example of the composition of an X-ray generating apparatus and the circuit structure of a high-frequency high-voltage generator.

[0017] Figure 2 This describes the processing of the high-frequency high-voltage generator after power input in an exemplary embodiment of this disclosure;

[0018] Figure 3 This is a power input circuit for a high-frequency high-voltage generator with grid power capacity detection function in an exemplary embodiment of this disclosure;

[0019] Figure 4 This is a block diagram of the power grid power detection function in an exemplary embodiment of this disclosure;

[0020] Figure 5 This is a schematic diagram of three-phase full-wave rectification in an exemplary embodiment of this disclosure;

[0021] Figure 6 This is the bus voltage waveform when the output power is relatively low in an exemplary embodiment of this disclosure;

[0022] Figure 7 The bus voltage waveform is shown when the output power is relatively high in the exemplary embodiment of this disclosure.

[0023] Figure 8 The bus voltage waveform is shown when the output power is relatively large in the exemplary embodiments of this disclosure, and when the internal resistance of the mains power supply is taken into account.

[0024] Figure 9 This is an exemplary embodiment of the power grid capacity detection process in this disclosure;

[0025] Figure 10 This illustrates the principle of the bus voltage sampling circuit in an exemplary embodiment of this disclosure.

[0026] Figure 11 The principle of the controllable discharge and discharge current detection circuit in the exemplary embodiments of this disclosure is shown.

[0027] The reference numerals in the attached figures are as follows:

[0028]

[0029] Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following embodiments are provided to further illustrate this disclosure in detail. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit this disclosure.

[0031] In one exemplary embodiment, an automatic detection circuit for a power generator is provided. The power generator's input terminal is connected to the power grid, and its output terminal is connected to a power-consuming component. The automatic detection circuit includes: a discharge circuit having a switch and a discharge resistor connected in series, the discharge resistor discharging the electrical energy generated by the power generator; and a control circuit controlling the opening and closing of the switch. Specifically, before the power generator supplies power to the power-consuming component, i.e., before the power generator needs to supply high-power power to the power-consuming component, the control circuit controls the switch to close and remain closed for a first time, discharging through the discharge resistor. The key means is that before the power generator supplies power to the power-consuming component, the power generator is discharged once using the discharge resistor of the automatic detection circuit. This discharge process can simulate the power consumption process of the power-consuming component, thereby allowing observation of the power generator's power supply status through the discharge process, achieving the purpose of automatic detection. More specifically, since the discharge is through a resistor, the voltage, current, and other indicators of the resistor are easily detected or calculated, and the power supply status of the power generator can be obtained through these indicators. This resistor can be one, multiple, or a variable resistor, thereby simulating the power consumption process of various electrical components and obtaining the power supply capacity of the power generator under various conditions.

[0032] In one exemplary embodiment, after the power generator supplies power to the electrical component, the control circuit controls the switch to close and continue for a second period of time, discharging through the discharge resistor. The discharge resistor serves two purposes: first, before supplying power to the electrical component, when the component may be in standby mode after power-on, the discharge resistor simulates the component's power consumption process, thereby detecting the power supply status of the power generator. The second purpose is to discharge excess energy from the power generator during the second period after power is supplied to the component, i.e., when the component no longer needs power, thus maintaining electrical safety.

[0033] In an exemplary embodiment, the power grid is alternating current (AC). The power generator further includes a rectifier and filter circuit for rectifying and filtering the AC power from the power grid. The automatic detection circuit also includes: a bus voltage detection circuit for acquiring the bus voltage value output by the rectifier and filter circuit; and a discharge current detection circuit for acquiring the discharge resistor current value during the discharge process at the first time interval, wherein the first time interval is greater than or equal to one cycle of the rectified waveform. In this embodiment, the indicators of detecting the bus voltage value and the discharge resistor current value can be used for subsequent power supply status detection. For example, detecting whether the bus voltage drops during the discharge process, or detecting whether the discharge capacity meets expectations, wherein this capacity can be reflected by the current value of the discharge resistor, thereby evaluating the power supply capability. Here, it is necessary that the first time interval is greater than one cycle of the rectified waveform to obtain complete power supply information, rather than only acquiring a portion of the entire cycle due to a short time interval.

[0034] In an exemplary embodiment, the discharge current detection circuit achieves this by measuring the voltage across a discharge resistor. By obtaining the voltage across the discharge resistor using its resistance value, the discharge current can be easily calculated, thereby determining the power supply capability. The purpose of detecting the discharge current is to detect capacitance-related indicators. Capacitance assessment does not necessarily involve directly calculating the capacitance itself. For example, simply obtaining the current through the discharge resistor also characterizes the capacitance; therefore, simply obtaining the current through the discharge resistor falls under the concept of capacitance detection. Other indicators are similar; anything that can characterize capacitance can be used to characterize capacitance.

[0035] In one exemplary embodiment, a power generator is disclosed. The input terminal of the power generator is connected to the alternating current (AC) power supply from the power grid, and the output terminal is connected to an electrical component. The power generator includes: a rectifier and filter circuit for rectifying and filtering the AC power supply from the power grid; and any of the aforementioned automatic detection circuits. In this embodiment, the power generator rectifies and filters the AC power supply from the power grid and includes an automatic detection circuit that can discharge the rectified and filtered output to detect the power supply capability of the power generator.

[0036] In one exemplary embodiment, a power generator is disclosed. The input terminal of the power generator is connected to the AC power of the power grid, and the output terminal is connected to an electrical component. The power generator includes: a rectifier and filter circuit for rectifying and filtering the AC power from the power grid; an automatic detection circuit including a bus voltage detection circuit and a discharge current detection circuit; and a calculation unit for calculating the internal resistance of the power grid based on the bus voltage and the voltage across the discharge resistor. The internal resistance of the power grid will cause voltage drop, especially under high current conditions, so the internal resistance of the power supply often needs to be known in advance. In this embodiment, the internal resistance of the power grid is calculated using the bus voltage and the voltage across the discharge resistor. Specifically, before supplying power to the electrical component, the control circuit controls the switch of the discharge circuit to open, and the calculation unit reads the first voltage of the bus; then the control circuit controls the switch of the discharge circuit to close, and the calculation unit reads the second voltage of the bus and the third voltage across the discharge resistor, and calculates the internal resistance of the power grid based at least on the first voltage, the second voltage, the third voltage, and the resistance value of the discharge resistor. More specifically, based on the difference between the first and second voltages, the voltage drop across the bus during discharge can be obtained; this voltage drop is the voltage drop caused by the internal resistance of the power grid. Then, based on the third voltage and the resistance of the discharge resistor, the discharge current can be calculated. The quotient of the voltage drop caused by the internal resistance and the discharge current gives the value of the internal resistance.

[0037] In an exemplary embodiment, the calculation unit also calculates the maximum power consumption of the electrical component based on the internal resistance of the power grid. After calculating the internal resistance, it is often necessary to estimate the maximum power that the electrical component can use, so that the operator knows in advance how much power the electrical component can operate at. Specifically, calculating the maximum power consumption of the electrical component includes: calculating the maximum output current using the current power grid voltage, the rated power supply tolerance value of the electrical component, and the internal resistance value of the power grid; then calculating the maximum power consumption of the electrical component using the maximum output current, the current power grid voltage, and the rated power supply tolerance voltage value of the electrical component. First, the difference between the current power grid voltage and the rated power supply tolerance voltage value of the electrical component is divided by the internal resistance of the power grid to obtain the maximum output current value under this power grid internal resistance. Finally, multiplying this maximum output current by the highest average voltage that the electrical component can reach yields the maximum power consumption of the electrical component. The above calculation process is merely an example. Various coefficients can be added according to the actual situation, such as coefficients added for single-phase electricity, three-phase electricity, or coefficients added for errors. These can be selected based on the convenience and accuracy of the calculation in engineering.

[0038] In one exemplary embodiment, the power-consuming component is an X-ray tube assembly, and the power generator further includes a filament heating circuit. This solution is particularly advantageous in scenarios where the X-ray tube assembly is powered, as it allows the X-ray tube assembly to achieve the maximum power achievable in the next exposure, avoiding ineffective exposures.

[0039] In one exemplary embodiment, a high-frequency high-voltage generator for an X-ray tube assembly is used as a power generator as a specific application scenario to illustrate an exemplary embodiment of this disclosure. X-ray generators are widely used in medical imaging. An X-ray generator consists of an X-ray tube assembly and a high-voltage generator for controlling the X-ray tube assembly. The high-voltage generator serves as the power supply for the X-ray generator, and the quality of its output power affects the final imaging quality. Therefore, how to obtain power quality has become a focus of attention in the industry. See also... Figure 1The X-ray generating device consists of two main components: a high-frequency high-voltage generator 2, which acts as the power generator, and an X-ray tube assembly 3, which is the power-consuming component. The X-ray tube assembly 3 generates electrons 5, which then bombard the anode to produce X-rays 4. For the rotating anode X-ray tube assembly, an anode rotation motor M is also needed to drive the rotation of the anode. The X-ray tube assembly 5 requires at least tens of kilovolts, such as 40kV to 150kV, which is provided by the high-frequency high-voltage generator 2. This high voltage is mainly applied between the anode and cathode to accelerate the electrons 5. In addition to the high voltage, the filament also requires power, which is also provided by the high-frequency high-voltage generator 2. Therefore, the high-frequency high-voltage generator 2 provides multiple power sources.

[0040] Because high-voltage generators in the industry widely use high-frequency inverters to generate DC high voltage to power X-ray tube assemblies, they are called high-frequency high-voltage generators. See also: Figure 1 The high-frequency high-voltage generator 2 includes a rectifier and filter circuit 21 after the input of the three-phase / single-phase grid power supply 1, a high-voltage main inverter circuit 22, a high-voltage oil tank 271 (containing a high-voltage transformer 272, large and small filament transformers 274, a high-voltage rectifier and filter circuit 273, etc.), a filament heating circuit 25, a rotating anode drive circuit 26 (if it is a rotating anode X-ray tube assembly), a generator control circuit 24, a low-voltage control power supply 23, and peripheral interface circuits 28, etc. After the three-phase / single-phase grid power supply 1 is introduced into the high-frequency high-voltage generator 2, various power supplies required by the X-ray generating device are generated. Among them, the high-voltage transformer 272 and the high-voltage rectifier and filter 273 in the high-voltage oil tank 271 are responsible for applying high voltage between the cathode and anode of the X-ray tube assembly, while the large and small filament transformers 274 are responsible for providing power to the filament in the cathode. The filament heating circuit 25 is responsible for powering the filament, and the rotating anode drive circuit 26 is responsible for driving the motor M of the anode target disk. The generator control circuit 24 is responsible for controlling the entire generator, such as regulating the high voltage, the filament power supply, and the anode rotation drive. The low-voltage control power supply 23 provides low-voltage power to the internal circuits or components in the high-frequency high-voltage generator 2. The power output from the rectifier and filter circuit 21 provides high-power power to the high-voltage main inverter circuit 22, the filament heating circuit 25, and the rotating anode drive circuit 26. The peripheral interface circuit 28 connects to peripheral components 6, such as external door switches, temperature switches, communication interfaces, and bed interfaces.

[0041] In one exemplary embodiment, see in particular Figure 2 It provides a Figure 1The intermediate rectifier filter circuit 21 is implemented in a manner that plays an important role in converting AC to DC. The circuit structure of the intermediate rectifier filter circuit 21 can be implemented in the following ways: (1) There is an overload protection module 2101, which is usually a circuit breaker or fuse. (2) There is an EMC power filter 2102, which is used to eliminate interference from the input power supply and EMC interference to the input power supply. (3) There are two contactors, namely the current-limiting contactor 2103 and the power-on contactor 2104. Under normal circumstances, a large inrush current will be generated when the large-capacity filter capacitor is first charged during power-on. In order to limit this current, the current-limiting contactor 2103 needs to be closed first. That is, a certain resistor is connected in series in the working circuit of this contactor to limit the charging current of the filter capacitor and prevent the instantaneous short circuit during the initial charging process of the capacitor. After a certain charging delay (generally after a few seconds, when the voltage on the filter capacitor rises to about 90% of the maximum voltage), the power-on contactor 2104 is closed. Thus, a control 2108 for the current-limiting contactor and the power-on contactor is needed to control the switching sequence of the two contactors. It is easy to understand that the control 2108 for the current-limiting contactor and the power-on contactor can be provided by the generator control circuit 24 or by other components with control functions. (4) There is a full-wave rectifier circuit module 2105, which is used to convert AC power into DC power. (5) There is a filter circuit module 2106, which generally uses capacitor filtering. The size of the capacitor is determined by the output power of the generator and is mainly used to smooth the DC power supply. (6) There is a discharge circuit 2107. After the power is turned off, in order to prevent the high voltage of several hundred volts on the capacitor from affecting safety, the electrical energy on the capacitor needs to be released to below the safe voltage of the human body through a discharge circuit. A normally closed contact switch is usually connected in series with a resistor to release the electrical energy. The discharge circuit is automatically disconnected when the power is turned on. The rectifier filter circuit 21 will eventually output a DC bus voltage output 2109, which can supply power to the high voltage main inverter circuit 22.

[0042] Figure 2The illustrated embodiment has the following problems: Problem 1: The internal resistance of the power supply is unknown. For high-voltage generators with different output power, the International Electrotechnical Commission (IEC) has clearly stipulated the requirements for the internal resistance of the power supply grid. If the internal resistance of the power supply grid is too high, it will lead to insufficient high-power output. Generally, equipment manufacturers require customers to provide site power distribution that meets the installation requirements before installing the machine. However, the grid conditions are generally not monitored during equipment operation. Once the internal resistance of the power supply grid changes, such as due to aging wiring or aging contacts of the power distribution circuit breaker, the internal resistance of the power supply grid may be too high. If high-power exposure is used at this time, it will cause the generator to report an error and produce an invalid exposure. Problem 2: In underdeveloped areas or areas with relatively scarce energy, the output voltage of the power distribution grid is often too low, even exceeding -10% of the lower deviation. This will cause the generator to malfunction. For emergency patients, in the case of Problem 1, the problem can be solved by manually reducing the exposure power; however, for Problem 2... Figure 2 The illustrated embodiment lacks an effective method for performing an exposure operation on an emergency patient. One solution to problem 2 above is that some generators will monitor the mains power voltage and / or bus voltage in real time to determine the state of the mains power supply. Once the mains voltage deviates below the specified -10% error, the generator will immediately generate an error message indicating that the generator cannot function properly.

[0043] In one exemplary embodiment, an automatic power supply detection circuit is provided, and the detection result determines the maximum exposure output power or energy of the generator, thereby ensuring the successful completion of the next exposure even under conditions of Problem 1 or Problem 2. See also: Figure 3 In contrast Figure 2 In the illustrated embodiment, a grid power capacity detection and discharge module 2110 replaces the discharge circuit 2107. The grid power capacity detection and discharge module 2110 not only has a discharge function but also a function for detecting the grid power supply capacity. (See the box below.) Figure 3 In this embodiment, the internal resistance of the three-phase / single-phase power supply 1 can be detected, thereby estimating the maximum exposure output power of the X-ray tube assembly and avoiding exposure failures caused by the internal resistance of the three-phase / single-phase power supply 1. Figure 3 The embodiment shown uses a grid power capacity detection and discharge module 2110 instead. Figure 2 The discharge circuit 2107 in the illustrated embodiment uses a high-power switch to control the on / off state of the discharge circuit. This switch is controllable and is controlled, for example, by a generator control circuit 24.

[0044] In one exemplary embodiment, see in particular Figure 4An exemplary implementation of a power grid capacity detection and discharge circuit 2110 is provided. The power grid capacity detection and discharge circuit 2110 includes the following components:

[0045] (1) Bus voltage detection circuit 21102: It needs to detect the bus voltage value, that is, the bus voltage value during standby, denoted as: V UDC .

[0046] (2) Controllable Discharge Circuit 21103: The aforementioned discharge circuit is controlled by the normally closed contact of the current-limiting contactor 2103. This controllable discharge circuit 21103 requires active control, for example, by the generator control circuit 24. That is, the controllable discharge switch SW is a normally closed switch. After shutdown, the current on the filter capacitor discharges through this normally closed switch to the resistor R. During startup, before the current-limiting contactor 2103 operates, the controllable discharge switch SW must be opened to stop the discharge circuit 21103 from operating. The discharge process is triggered by the generator control circuit 24 triggering the high-power controllable discharge switch SW to open and close.

[0047] (3) Discharge current detection circuit 21104: Discharge current detection first requires instantaneous discharge current detection. The current detection is achieved here by measuring the voltage across the discharge resistor R, denoted as V. R .

[0048] (4) Calculation of capacitance: The following uses a three-phase input power supply as an example to explain the calculation of capacitance; Figure 5 A schematic diagram of a three-phase rectifier filter is given. L1, L2, and L3 represent the three-phase electricity, and the solid line represents the DC output after rectification. The peaks are represented by V. max The trough is represented by V. min express.

[0049] After powering on, during standby, we can measure the three-phase power supply rectified and filtered voltage as V using the steps (1) above. UDC ; This V UDC It is the filtered voltage value, that is Figure 5 V in max From this, the line voltage V of the three-phase power supply can be calculated. L-L =V UDC / √2, that is, by measuring V UDC To obtain the voltage from the power grid.

[0050] When the exposure power is low, V UDC The waveform is as follows Figure 6 As shown. Assuming exposure begins at time t1; then, within the time range t1≤t≤t2, the voltage across the filter capacitor decreases exponentially as follows:

[0051] V UDC (t)=V UDC ·e -t / τ ;(t1≤t≤t2) Formula 1

[0052] Here, C represents the total capacitance of the filter capacitors; τ is the time constant, τ = R. L *C, where:

[0053] R L =V UDC / I L

[0054] I L This is the current output by the bus voltage during exposure;

[0055] At time t2, the grid power supply voltage rises to the voltage across the filter capacitor. At this time, the grid power supply not only provides energy to the exposure load but also charges the filter capacitor.

[0056]

[0057] At time t3, the voltage across the filter capacitor rose to V again. UDC Subsequently, due to the drop in mains power voltage, the voltage across the filter capacitor began to rise again according to V. UDC (t)=V UDC ·e -t / τ Formula 1 (t1≤t≤t2) provides electrical energy to the exposure load.

[0058] See also Figure 7 When the exposure power is high, that is, when the bus voltage outputs current I during exposure... L If R is very large, then L The voltage is very small, and the time constant τ is also very small, meaning the energy stored in the filter capacitor is insufficient to provide energy for exposure, and it must be supplied by the mains power supply. During exposure, the waveform of the bus voltage is as follows: Figure 7 As shown. When exposure begins, the bus voltage and grid power waveform are the same, and all the input current is supplied to the output, making it difficult for the capacitor to store energy.

[0059] Figure 6 and Figure 7 The scenario and analysis presented here ignore the internal resistance of the mains power supply. While this may be negligible at lower power outputs, it cannot be ignored at higher power outputs. In such cases, the mains power supply voltage will decrease due to the influence of the internal resistance. Figure 8 As shown. Starting from t1, the internal resistance of the mains power supply begins to divide the voltage, causing a voltage drop in the bus voltage.

[0060] At this point, if the bus voltage is measured during the exposure process, the measured peak voltage is V'. max ;

[0061] V in standby mode max There is a voltage difference between them, that is:

[0062] ΔV=V max -V′ max Formula 3

[0063] This voltage drop ΔV is the voltage drop caused by the internal resistance of the mains power supply. If the current I consumed during the exposure process can be obtained... L Then the internal resistance of the grid power supply can be calculated.

[0064] Of course, we need to obtain the internal resistance value of the grid power supply before exposure so that we can predict whether the next exposure will exceed the grid capacity. This embodiment utilizes a controllable discharge circuit 21103. It should be noted that in order to simulate high-power exposure, the resistor R in the discharge circuit 21103 must be set small, such as 10 ohms or even 1 ohm. This value is only an example for illustration purposes, and those skilled in the art can choose according to the actual situation, as long as it can simulate a high-power exposure of the X-ray tube assembly 3. If the control discharge circuit needs to perform a large current discharge for a short period of time, which is at least longer than one cycle of the rectified waveform, and detect the magnitude of the discharge current:

[0065] I R =V R / R

[0066] Simultaneously, the bus voltage is sampled during the discharge process, and the peak voltage within the measurement time is taken as V'. max Therefore, the internal resistance r of the mains power supply can be calculated. i :

[0067] r i =(V UDC -V′ max )·R / V R Formula 4

[0068] Therefore, the internal resistance r of this power supply network can be calculated. i Maximum output current i max :

[0069]

[0070] V here nominal This is the generator's rated power supply voltage. 10% is the lower bias tolerance value. If the equipment specifies 15%, then use 15%. It should be noted that the lower bias tolerance value is a tolerable error; that is, if the lower bias tolerance value is 10%, then exposure can be completed using 90% of the voltage.

[0071] Therefore, the maximum power that the device can output at this time is:

[0072]

[0073] Here This is the maximum average voltage that can be output during exposure. This value can also be adjusted according to actual needs.

[0074] In one exemplary embodiment, see in particular Figure 9 The flowchart for capacitance detection is shown. A detailed explanation follows:

[0075] S1: High-frequency high-voltage generator 2 in standby state;

[0076] S2: Photography Preparation;

[0077] S3: Detect bus voltage V UDC

[0078] S4: Perform a discharge:

[0079] 1. The discharge time is one cycle of the rectified waveform;

[0080] 2. Collect the voltage across the discharge resistor R, and take the maximum voltage value V. R ;

[0081] 3. Detect the bus voltage during the discharge process and take the maximum voltage value V'. max ;

[0082] S5: Calculate the internal resistance of the mains power supply using formula 4;

[0083] S6: Use formula 6 to calculate the maximum power that the generator can output at this time.

[0084] The power generator and its automatic detection device and detection method according to the embodiments of this disclosure have at least the following beneficial effects:

[0085] (1) In economically underdeveloped areas, remote mountainous areas, and areas with poor power grids, the generator can be used in an active downgrade mode to ensure that emergency patients can be diagnosed normally.

[0086] (2) The power generator can detect the internal resistance of the power grid at any time and can detect problems such as aging power supply lines, failure of distribution air switch contacts, and failure of power contactors in advance.

[0087] (3) The power generator is more intelligent and can determine whether the exposure will exceed the capacity of the power supply before exposure.

[0088] In one exemplary embodiment, the following can be employed: Figure 10The circuit principle obtains the bus voltage sampling. Its basic principle is to obtain the voltage proportionally through resistor voltage division and voltage sampling circuit 2112. Since our generator control circuit 24 is low voltage, an optocoupler-isolated ADC device 2113 is required to send the sampled voltage to the generator control circuit 24 in digital form.

[0089] In one exemplary embodiment, the following can be employed: Figure 11 The circuit principle enables controllable discharge and discharge current detection. When the generator control circuit 24 turns the switch on, current does not flow through R2, so Q is not conducting, and discharge is impossible. When the generator control circuit 24 stops supplying power, current flows through R1 and R2, causing Q to conduct. Current then flows through resistor R, and the voltage drop across R can be measured by the voltage sampling circuit 2114. The digital signal is then sent to the generator control circuit 24 via the optocoupler-isolated ADC device 2115.

[0090] According to another aspect of the present disclosure, a non-transitory computer-readable storage medium storing a computer program is provided, wherein the computer program, when executed by a processor, implements an automatic detection method according to any of the above embodiments of the present disclosure.

[0091] According to another aspect of the embodiments of the present disclosure, a computer program product is provided, comprising a computer program, wherein the computer program, when executed by a processor, implements an automatic detection method according to any of the above embodiments of the present disclosure.

[0092] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), payload-programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0093] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0094] In the context of this disclosure, a computer-readable storage medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium can be a computationally readable signal medium or a computer-readable storage medium. A computer-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0095] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0096] While embodiments or examples of this disclosure have been described with reference to the accompanying drawings, it should be understood that the methods, systems, and devices described above are merely exemplary embodiments or examples, and the scope of the invention is not limited by these embodiments or examples, but only by the granted claims and their equivalents. Various elements in the embodiments or examples may be omitted or replaced by their equivalents. Furthermore, the steps may be performed in a different order than that described in this disclosure. Importantly, as technology evolves, many elements described herein can be replaced by equivalents that appear after this disclosure.

[0097] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

Claims

1. A power generator, wherein the input terminal of the power generator is connected to AC power from the power grid, and the output terminal is connected to an electrical component, wherein the electrical component is an X-ray tube assembly, characterized in that, The power generator includes: A rectifier and filter circuit is used to rectify and filter the AC power from the power grid. Automatic detection circuit, the automatic detection circuit comprising: A discharge circuit having a switch and a discharge resistor connected in series, the discharge resistor discharging the electrical energy generated by the power generator, and using the discharge resistor to simulate the power consumption process of the electrical component; A control circuit that controls the opening and closing of the switch; A bus voltage detection circuit is used to obtain the bus voltage value output by the rectifier and filter circuit; Specifically, before the power generator supplies power to the electrical component, the control circuit controls the switch to close and remain closed for a first time to discharge through the discharge resistor; and after the power generator supplies power to the electrical component, the control circuit controls the switch to close and remain closed for a second time to discharge through the discharge resistor. The calculation unit is used to calculate the internal resistance of the power grid based on the bus voltage and the voltage across the discharge resistor.

2. The power generator according to claim 1, Before supplying power to the electrical components, the control circuit controls the switch of the discharge circuit to open, and the calculation unit reads the first voltage of the bus; then the control circuit controls the switch of the discharge circuit to close, and the calculation unit reads the second voltage of the bus and the third voltage across the discharge resistor, and calculates the internal resistance of the power grid based at least on the first voltage, the second voltage, the third voltage and the resistance value of the discharge resistor.

3. The power generator according to claim 1, wherein the calculation unit further calculates the maximum power consumption of the power-consuming component based on the internal resistance of the power grid.

4. The power generator according to claim 3, wherein calculating the maximum power consumption of the electrical component includes: The maximum output current is calculated using the bias tolerance value of the power supply and the internal resistance of the power grid. The maximum power consumption of the electrical component is calculated using the maximum output current and the rated power supply voltage of the electrical component.

5. The power generator according to claim 1, further comprising: Filament heating circuit.

6. The power generator according to claim 1, wherein the automatic detection circuit further comprises: A discharge current detection circuit is used to obtain the discharge resistance current value during the discharge process at the first time. Furthermore, the first time is greater than or equal to one period of the rectified waveform.

7. The power generator according to claim 6, wherein the discharge current detection circuit is implemented by measuring the voltage across the discharge resistor.

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