Power supply system for ultralow field magnetic resonance

Abstract

The invention provides a power supply system for ultra-low field magnetic resonance, the power supply system comprises a storage battery and a common power supply conversion module, the ultra-low field magnetic resonance further comprises a load end, the load end comprises a gradient system, a radio frequency system, a spectrometer system and a computer console, the power supply system is characterized by comprising the storage battery used for providing a main power supply; the common power supply conversion module is connected with the storage battery, is provided with a high-voltage output unit and a low-voltage output unit, and is used for outputting high voltage from the voltage of the storage battery through the high-voltage output unit and outputting low voltage from the voltage of the storage battery through the low-voltage output unit; the high-voltage output unit is used for supplying power to the gradient system and the radio frequency system; the low-voltage output unit is used for supplying power to the gradient system, the radio frequency system, the spectrometer system and the computer console, the structure of the power supply system is simplified by sharing the power supply conversion module, and the manufacturing cost and the equipment maintenance complexity are reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-low field magnetic resonance equipment, and in particular to a power supply system for ultra-low field magnetic resonance. Background Art

[0002] Ultra-low-field magnetic resonance imaging (ULFMRI) is a key branch of magnetic resonance imaging (MRI) and generally refers to MRI systems with magnetic field strengths below 0.5 Tesla. Existing ULFMRI devices typically utilize multiple independent power conversion modules distributed within components such as gradient amplifiers and radio frequency amplifiers, each of which provides power for its own circuits. This not only increases the size and weight of the device, but also increases manufacturing costs and maintenance complexity. This paper proposes a mobile (battery-powered) power supply system architecture for ULFMRI. By sharing power conversion modules, this system simplifies the power supply structure, improves energy efficiency, and reduces costs. Summary of the Invention

[0003] In view of this, an object of the present invention is to provide a power supply system for ultra-low field magnetic resonance, so as to simplify the structure of the power supply system, improve energy utilization and reduce costs.

[0004] An embodiment of the present invention provides a power supply system for ultra-low field magnetic resonance.

[0005] Provided is a power supply system for ultra-low field magnetic resonance imaging, comprising a battery and a shared power conversion module. The ultra-low field magnetic resonance imaging system further comprises a load end, which comprises a gradient system, a radio frequency system, a spectrometer system, and a computer console. The system is characterized in that it comprises: Batteries, used to provide main power; A common power conversion module is connected to the battery. The common power conversion module has a high-voltage output unit and a low-voltage output unit, and is used to output the battery voltage as a high voltage through the high-voltage output unit and as a low voltage through the low-voltage output unit. The high voltage output unit is used to power the gradient system and radio frequency system; The low voltage output unit is used to power the gradient system, radio frequency system, spectrometer system and computer console. A second possible implementation is provided, including: The high-voltage output unit adopts a phase-shifted full-bridge topology circuit with an output power greater than 1000w; The low-voltage output unit adopts a flyback circuit and the output power is less than 100w.

[0006] A third possible implementation is provided, including: A startup control and filtering module, which includes a startup control circuit and a filtering circuit; The starting control circuit includes a resistor and a control switch connected in parallel; The start control circuit is connected to the high voltage output unit. One end of the filter circuit is connected to the start control circuit, and the other end is connected to the gradient system and the radio frequency system.

[0007] A fourth possible implementation is provided, including: A power supply intelligent control module connected to the low-voltage output unit, the power supply intelligent control module including a power sampling unit and a power adjustment unit; The power sampling unit collects power consumption at the load end, where the power consumption is at least one of voltage, current, and output power; The power adjustment unit adjusts the output voltages of the high-voltage output unit and the low-voltage output unit according to the power consumption of the load end.

[0008] A fifth possible implementation is provided, including: When the battery is connected to the mains through the charging module, the power adjustment unit controls the mains to charge the battery and supply power to the common power conversion module; When the battery is not connected to the mains, the power adjustment unit controls the battery to supply power to the common power conversion module.

[0009] A sixth possible implementation is provided, including: The battery includes a power supply intelligent management module, which includes a charge and discharge protection circuit and a charge state monitoring circuit; The state of charge monitoring circuit is used to monitor the battery power in real time; The charge and discharge protection circuit is used to control the charging state or power supply state of the battery according to the monitoring results of the charge state monitoring circuit.

[0010] A seventh possible implementation is provided, including: The power sampling unit is connected to the state of charge monitoring circuit to collect the power of the battery; When the battery supplies power to the common power conversion module, the power at the load end is adjusted according to the power level of the battery.

[0011] An eighth possible implementation is provided, including: The heat dissipation device is arranged on the common power conversion module, so that both the high-voltage output unit and the low-voltage output unit are cooled by the heat dissipation device.

[0012] A ninth possible implementation is provided, including: An electrolytic capacitor is connected in parallel to the input end of the high-voltage output unit.

[0013] A tenth possible implementation is also provided, including: An energy feedback circuit is set between the high-voltage output unit and the gradient system. The energy feedback circuit is used to capture the reverse electromotive force when the gradient system switches the gradient magnetic field and convert it into electrical energy and store it in the battery.

[0014] The embodiments of the present invention bring the following beneficial effects: By sharing the power conversion module, the structure of the power supply system is simplified, reducing manufacturing costs and equipment maintenance complexity; Improve energy utilization through the power intelligent control module to meet the needs of energy conservation and environmental protection.

[0015] Other features and advantages of the present disclosure will be set forth in the following description, or some features and advantages may be inferred or unambiguously determined from the description, or may be learned by practicing the above-mentioned technology of the present disclosure.

[0016] In order to make the above-mentioned objectives, features and advantages of the present disclosure more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 A framework diagram of a power supply system for ultra-low field magnetic resonance provided by an embodiment of the present invention; Figure 2 A framework diagram of an ultra-low field magnetic resonance power supply system including a power supply intelligent control module provided in an embodiment of the present invention; Figure 3 A circuit diagram of a startup control and filtering module of an ultra-low field magnetic resonance power supply system provided by an embodiment of the present invention; Figure 4 This is a heat dissipation layout diagram of a power supply system for ultra-low field magnetic resonance provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] To facilitate understanding of this embodiment, a magnetic resonance image analysis system disclosed in an embodiment of the present invention is first introduced in detail.

[0021] Figure 1 A framework diagram of a power supply system for ultra-low field magnetic resonance provided in an embodiment of the present application.

[0022] Specifically, the power supply system includes a battery and a common power conversion module. The ultra-low field magnetic resonance also includes a load end, which includes a gradient system, a radio frequency system, a spectrometer system and a computer console. The battery of the power supply system is used to provide the main power supply; the common power conversion module is connected to the battery, and the common power conversion module has a high-voltage output unit and a low-voltage output unit, which are used to output the battery voltage as a high voltage through the high-voltage output unit and as a low voltage through the low-voltage output unit; the high-voltage output unit is used to power the gradient system and the radio frequency system; the low-voltage output unit is used to power the gradient system, the radio frequency system, the spectrometer system and the computer console.

[0023] The gradient system of an ultra-low-field MRI device superimposes a linearly varying gradient magnetic field on a static magnetic field through gradient coils, creating the magnetic field gradients required for spatial encoding. The radio frequency (RF) system transmits RF pulses, enabling the RF generator to generate RF pulses of a specific frequency, which are then driven by a power amplifier to stimulate hydrogen proton resonance. It also receives signals, capturing the RF signals released by hydrogen proton relaxation through a receiving coil and transmitting them to the spectrometer system via a low-noise amplifier and analog-to-digital converter. The spectrometer system precisely controls the timing of the gradient field, RF pulses, and signal acquisition, generating the corresponding pulse sequence and triggering the gradient system to select slices in the Z-axis and perform encoding in the X- and Y-axes. A computer console is used for human-computer interaction and image reconstruction.

[0024] Ultra-low-field MRI equipment may also include: a motion-assistance system for securing and supporting the patient, ensuring the patient remains stationary during scanning; a motion control system for, in certain circumstances, moving the patient or adjusting the scanning position; a wireless communication module for remote monitoring and data transmission, allowing users to view imaging results and system status on a mobile or remote device; and an environmental sensing module, which may include temperature and humidity sensors, for monitoring the equipment's operating environment to ensure the equipment operates under appropriate conditions, automatically adjusting the equipment's operating parameters based on environmental conditions, and improving stability and reliability. The aforementioned systems and modules can be integrated into the ultra-low-field MRI equipment as components. To enable the operation of these components, the present invention provides a power supply system for ultra-low-field MRI. The power supply system includes a battery and a shared power conversion module, wherein the battery is a removable power supply device that provides the main power supply for the aforementioned components. The shared power conversion module is connected to the battery and includes a high-voltage output unit formed using a phase-shifted full-bridge topology circuit. This high-voltage output unit is capable of outputting greater than 1000W of power and can provide high-voltage power to the gradient system and the radio frequency system, such as the gradient power amplifier and gradient coil of the gradient system and the radio frequency power amplifier and transmitting coil of the radio frequency system. The input end of the high-voltage output unit is connected in parallel with an electrolytic capacitor to store a certain amount of electrical energy. When the circuit load changes instantaneously or the power supply is briefly interrupted, the stored electrical energy is released in time to realize its transient power and maintain the circuit voltage stable, thus playing the role of energy buffering.

[0025] The shared power conversion module also features a low-voltage output unit using a flyback circuit, capable of outputting less than 100W of power. The flyback circuit converts the input voltage into multiple low-voltage outputs. Through transformer coupling and control of switching devices, the flyback circuit achieves voltage reduction and multiple outputs. The low-voltage output unit can power the gradient system, RF system, spectrometer system, and the computer console. It can also power other components requiring low-voltage power, such as the motion assistance system, motion control system, wireless communication module, and environmental sensing module. The gradient system and RF system contain circuits requiring low-voltage power, such as the gradient controller, cooling system, and sensors in the gradient system, and the receiving coil, RF generator, and control circuit in the RF system. The shared low-voltage power supply of the shared power conversion module is shared, eliminating the need for additional high-voltage to low-voltage voltage conversion circuitry within the gradient / RF system. This simplifies system complexity, reduces costs, and improves system power efficiency, as each voltage conversion results in power loss.

[0026] Figure 2A framework diagram of a power supply system for an ultra-low field magnetic resonance imaging (UFMRI) apparatus including an intelligent power supply control module provided in an embodiment of the present invention. A low-voltage output unit is used to supply power to the intelligent power supply control module, which includes a power sampling unit and a power adjustment unit. The power sampling unit is used to collect power consumption at the load end, which is any component of the UFMRI apparatus in the embodiment of the present invention, such as a gradient system, a radio frequency system, a spectrometer system, the power supply for the computer console, a motion assistance system, a motion control system, a wireless communication module, an environmental sensing module, and the like. The power sampling unit is arranged on the output channels of each load end, including channels for the high-voltage output unit to supply power to the gradient system and radio frequency system, and channels for the low-voltage output unit to supply power to the spectrometer system and the computer console, etc. By continuously and in real time collecting voltage or current data, the intelligent power supply control module can promptly grasp the operating status and energy consumption requirements of each load. Collecting load-side power consumption. Specifically, at least one of the load-side voltage, current, and output power can be collected. This allows real-time monitoring of the operating status and energy consumption of device components. The results of this centralized monitoring can provide information for fault diagnosis of ultra-low-field MRI equipment or individual components. For example, by monitoring the voltage or current supplied to the gradient / RF system, diagnostic information can be provided to the gradient / RF system to determine whether operational anomalies are related to power supply.

[0027] The power adjustment unit adjusts the output voltages of the high-voltage and low-voltage output units based on the load's power consumption. For example, the power adjustment unit employs a fuzzy adaptive PID algorithm to adjust the switching frequency and duty cycle of the phase-shifted full-bridge topology circuit based on real-time load power consumption changes, maintaining power conversion efficiency above 90%. The flyback circuit of the low-voltage output unit utilizes synchronous rectification technology and features a dynamic load adjustment circuit on the secondary side, ensuring a cross-regulation error of less than ±2% for the multiple output voltages. Simultaneously, the power adjustment unit adjusts the output parameters of these two units based on analysis results from a preset algorithm, including output voltage and output current limits. Dynamically adjusting the output parameters of the high-voltage and low-voltage output units aims to ensure more efficient and stable operation of the entire load. For example, if the power demand of a load suddenly increases, the power supply intelligent control module can promptly increase the voltage or current of the corresponding output channel to meet the load's demand. Conversely, if the power demand of a load decreases, the intelligent control module can reduce the output parameters to minimize energy waste.

[0028] For example, during an ultra-low-field MRI process, the gradient power amplifier (GPA) needs to rapidly switch gradient magnetic fields, significantly increasing its power requirements. The power sampling unit (PSU) detects sharp increases in the GPA channel's current in real time and transmits this data to the intelligent power control module. A pre-set algorithm within the module analyzes this data and determines that the GPA requires additional power. The module then adjusts the output parameters of the high-voltage output module, increasing the output voltage and current to ensure proper functioning of the GPA and thus maintain the quality of the MRI. Furthermore, to ensure power balance across the system, the pre-set algorithm may appropriately reduce or disconnect power to other non-critical loads.

[0029] Figure 3 The startup control and filtering module circuit diagram of the ultra-low field magnetic resonance power supply system provided by the embodiment of the present invention is combined with Figure 2 As can be seen, the startup control and filtering module includes a startup control circuit and a filtering circuit. The startup control circuit includes a resistor and a control switch connected in parallel. The resistor limits the initial current, preventing damage to other circuit components due to excessive current. During the startup process, the control switch (such as a MOSFET or IGBT) gradually turns on, allowing the output voltage to gradually rise to the target value, avoiding current surges. Simultaneously, by controlling the on-time of the control switch, a smooth rise in output voltage is achieved, ensuring a smooth high-voltage charging startup process. The filtering circuit can be a π-type filter. During the power conversion process, the high-frequency switching action of the switching device generates electromagnetic interference. The filtering circuit filters out high-frequency noise, reduces electromagnetic interference, ensures output voltage stability, and prevents device damage or performance degradation caused by voltage fluctuations.

[0030] Because the gradient / RF power amplifier contains large busbar support capacitors, a power sampling unit is required to collect the power consumption of the support capacitor voltage to prevent current overshoot during startup. After precharging, the control switch is closed to prevent current overshoot and damage to the gradient / RF power amplifier. The power adjustment unit also adjusts the on / off state and on-time of the control switch based on the power consumption requirements of the gradient and RF systems.

[0031] Figure 2In the present invention, the battery is connected to the mains power through a charging module. The mains power is AC power, and the battery needs to be charged with DC power. The charging module includes an AC / DC rectifier for converting AC power into DC power and cooperating with the charging control circuit of the charging module to charge the battery. When the battery is connected to the mains power through the charging module, the power adjustment unit controls the mains power to charge the battery and supply power to the shared power conversion module; when the battery is not connected to the mains power, the power adjustment unit controls the battery to supply power to the shared power conversion module. The present invention uses a high-performance battery as a power supply to ensure that the ultra-low field magnetic resonance equipment can still operate normally when it is moved or cannot be connected to the mains power.

[0032] The battery of the present invention includes an intelligent power management module, which includes a charge-discharge protection circuit and a state-of-charge monitoring circuit. The state-of-charge monitoring circuit is used to monitor the battery's charge level in real time. The charge-discharge protection circuit is used to control the battery's charge level or power supply level based on the monitoring results of the state-of-charge monitoring circuit. When the state-of-charge monitoring circuit detects that the battery is "pre-charged" (the charge level is higher than a preset value), the charge-discharge protection circuit switches the charging state to "trickle charging" (the current is reduced to 0.1C) or completely disconnects the charging circuit. When the state-of-charge monitoring circuit detects that the battery is "low charge" (the charge level is lower than a preset value), the charge-discharge protection circuit switches the power supply state to a staged power cutoff or a complete power cutoff at the load end. The staged power cutoff may first disconnect the power supply to the computer console and then disconnect the power supply to the gradient power amplifier. The intelligent power management module controls the battery's charge and discharge, preventing overcharging or over-discharging, thereby extending the battery's service life and improving energy efficiency.

[0033] The power sampling unit is connected to the state-of-charge monitoring circuit and is used to collect the power level of the battery. When the battery supplies power to the common power conversion module, the power at the load end is adjusted according to the power level of the battery. For example, if the power sampling unit receives a "low battery" alarm from the state-of-charge monitoring circuit or the power level is lower than a preset value, the load end hierarchical management is initiated: non-essential loads (such as motion assistance systems) are disconnected or the output power of the gradient power amplifier and the radio frequency power amplifier is reduced (for example, to 70% of the rated power).

[0034] Figure 4 The figure shows the heat dissipation layout of the power supply system for ultra-low field magnetic resonance imaging. The heat dissipation device is placed on the common power conversion module, allowing both the high-voltage output unit and the low-voltage output unit to be cooled by the heat dissipation device. The common power conversion module is cooled by a common radiator. This makes the power supply system provided by this invention highly integrated and reduces the size of the device.

[0035] The present invention also incorporates an energy feedback circuit between the high-voltage output unit and the gradient system. This circuit is used to capture the back electromotive force during the gradient magnetic field switching of the gradient system and convert it into electrical energy for storage in the battery. The power supply system provided by the present invention provides energy recovery capabilities for ultra-low-field magnetic resonance imaging (ULFMRI), extending the battery's usable life and improving device availability.

[0036] Unless otherwise specifically stated, the relative steps, numerical expressions and values of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0037] In all examples shown and described herein, any specific values should be interpreted as merely exemplary and not limiting, and thus other examples of the exemplary embodiments may have different values.

[0038] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A power supply system for ultra-low field magnetic resonance imaging, comprising a battery and a shared power conversion module. The ultra-low field magnetic resonance imaging system further comprises a load terminal, wherein the load terminal comprises a gradient system, a radio frequency system, a spectrometer system, and a computer console. include: Batteries, used to provide main power; a common power conversion module connected to the battery, the common power conversion module comprising a high-voltage output unit and a low-voltage output unit, configured to output the battery voltage as a high voltage through the high-voltage output unit and as a low voltage through the low-voltage output unit; The high voltage output unit is used to supply power to the gradient system and the radio frequency system; The low-voltage output unit is used to supply power to the gradient system, the radio frequency system, the spectrometer system and the computer console.

2. The power supply system according to claim 1, characterized in that: include: The high-voltage output unit adopts a phase-shifted full-bridge topology circuit with an output power greater than 1000W; The low-voltage output unit adopts a flyback circuit and has an output power of less than 100W.

3. The power supply system according to claim 1, wherein: Also includes: A startup control and filtering module, comprising a startup control circuit and a filtering circuit; The startup control circuit includes a resistor and a control switch connected in parallel; The startup control circuit is connected to the high-voltage output unit. One end of the filter circuit is connected to the startup control circuit, and the other end is connected to the gradient system and the radio frequency system.

4. The power supply system according to claim 1, wherein: Also includes: A power supply intelligent control module connected to the low-voltage output unit, the power supply intelligent control module including a power sampling unit and a power adjustment unit; The power sampling unit collects the power consumption of the load end, where the power consumption is at least one of voltage, current, and output power; The power adjustment unit adjusts the output voltages of the high-voltage output unit and the low-voltage output unit according to the power consumption of the load end.

5. The power supply system according to claim 4, characterized in that: Also includes: When the storage battery is connected to the mains power through the charging module, the power adjustment unit controls the mains power to charge the storage battery and supply power to the common power conversion module; When the storage battery is not connected to the mains, the power adjustment unit controls the storage battery to supply power to the common power conversion module.

6. The power supply system according to claim 5, characterized in that: Also includes: The battery includes a power supply intelligent management module, which includes a charge and discharge protection circuit and a charge state monitoring circuit; The state of charge monitoring circuit is used to monitor the power of the battery in real time; The charge and discharge protection circuit is used to control the charging state or power supply state of the battery according to the monitoring result of the charge state monitoring circuit.

7. The power supply system according to claim 6, characterized in that: Also includes: The power sampling unit is connected to the state of charge monitoring circuit and is used to collect the power of the battery; When the storage battery supplies power to the common power conversion module, the power of the load end is adjusted according to the power level of the storage battery.

8. The power supply system according to claim 1, wherein: Also includes: An electrolytic capacitor is connected in parallel to the input end of the high-voltage output unit.

9. The power supply system according to claim 1, wherein: Also includes: A heat dissipation device is arranged on the common power conversion module, so that the high-voltage output unit and the low-voltage output unit are both cooled by the heat dissipation device.

10. The power supply system according to claim 1, wherein: Also includes: An energy feedback circuit is provided between the high-voltage output unit and the gradient system. The energy feedback circuit is used to capture the reverse electromotive force when the gradient system switches the gradient magnetic field, and convert it into electrical energy and store it in the battery.

Images