A bidirectional intelligent tuning power supply system for underwater equipment

Abstract

This invention belongs to the field of power electronics technology, specifically relating to a bidirectional intelligent tuned power supply system for underwater equipment, comprising: an input circuit, a first resonant circuit, a transformer, a second resonant circuit, and an output circuit connected in sequence; the first and second resonant circuits have identical structures; the drains of the first and second switching transistors are connected, the sources of the third and fourth switching transistors are connected, the sources of the first and third switching transistors are connected, the sources of the second and fourth switching transistors are connected, the drain of the fourth switching transistor is connected to one end of a first resonant capacitor bank, the other end of the first resonant capacitor bank is connected to a first resonant inductor bank, and the first resonant inductor bank is connected to the transformer. This application features the advantage that both the resonant inductor and resonant capacitor can be discretely adjusted over a wide range, precisely matching the resonant requirements of electric drives with different power ratings.

Description

Technical Field

[0001] This invention belongs to the field of power electronics technology, specifically relating to a bidirectional intelligent tuned power supply system for underwater equipment. Background Technology

[0002] In underwater operations, such as deep-sea exploration equipment and underwater vehicles, various electric drives and motors with different power ratings are used, and the operating conditions are complex and variable. Traditional underwater power supplies are designed with fixed resonant parameters, which cannot be adjusted according to the characteristics of the electric drives and motors and real-time operating conditions. This not only leads to low efficiency under light loads but also makes it difficult to adapt to electric drives with different power ratings, resulting in insufficient reliability and stability of the power supply, which seriously restricts the stable operation of underwater equipment.

[0003] Existing CLLC resonant topology power supplies mostly use fixed parameters or simple segmented control, which makes it difficult to meet the comprehensive requirements of wide power adaptability, soft switching under all operating conditions, high efficiency under light load and bidirectional energy management. They cannot meet the stringent application scenarios of deep-sea high pressure, low temperature and sealed miniaturization. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a bidirectional intelligent tuned power supply system for underwater equipment, in which the resonant inductor and resonant capacitor can be discretely adjusted over a wide range, with high tuning accuracy and a wide power coverage range, and can accurately match the resonant requirements of electric drives with different power.

[0005] A bidirectional intelligent tuned power supply system for underwater equipment includes: The input circuit, the first resonant circuit, the transformer, the second resonant circuit, and the output circuit are connected in sequence. The first resonant circuit and the second resonant circuit have the same structure. The first resonant circuit includes a first switch, a second switch, a third switch, a fourth switch, a first resonant capacitor group, and a first resonant inductor group. The drain of the first switch is connected to the drain of the second switch, the source of the third switch is connected to the source of the fourth switch, the source of the first switch is connected to the drain of the third switch, the source of the second switch is connected to the drain of the fourth switch, the drain of the fourth switch is connected to one end of the first resonant capacitor group, the other end of the first resonant capacitor group is connected to the first resonant inductor group, and the first resonant inductor group is connected to the transformer.

[0006] Optionally, the first resonant capacitor bank includes: Several capacitors with different capacitance values ​​are given, and the capacitance values ​​of these capacitors satisfy the following relationship:

[0007] in, Here, m is the base capacitance value, and m is the number of switched capacitor branches in the resonant capacitor bank. Let be the capacitance of the m-th capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET.

[0008] Optionally, the first resonant inductor group includes: Several capacitors with different capacitance values ​​are connected to a resonant inductor. The capacitance values ​​of the different capacitors satisfy the following relationship:

[0009] in, Where n is the minimum capacitance value, and n is the number of switched capacitor branches in the resonant inductor group. Let n be the capacitance of the nth capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET.

[0010] Optionally, the input circuit includes: The first inductor, the first capacitor, and the second inductor are connected in sequence. One end of the first capacitor is connected to the drain of the first switching transistor, and the other end of the first capacitor is connected to the source of the third switching transistor. The first inductor is connected to the positive terminal of the power supply, and the second inductor is connected to the negative terminal of the power supply.

[0011] Optionally, a third inductor, a second capacitor, and a fourth inductor are connected in sequence; The two ends of the second capacitor are connected to the second resonant circuit.

[0012] Optionally, the first, second, third, and fourth switching transistors are all MOSFETs.

[0013] Optionally, the gates of the first, second, third, and fourth switching transistors are connected to the pulse control circuit.

[0014] Optionally, the capacitance value can be adjusted by turning the MOSFET on or off.

[0015] Optionally, the inductance value can be adjusted by turning the MOSFET on or off.

[0016] An adaptive control method for underwater electric drive power supplies, applied to a bidirectional intelligent tuned power supply system for underwater equipment, includes: Real-time data of the underwater electric drive power supply is collected, including output voltage, load current, and input voltage. Based on the real-time data, the current operating condition can be identified; Based on the real-time data, the comprehensive deviation is calculated, and the first resonant capacitor group and the first resonant inductor group are adjusted according to the comprehensive deviation to adjust the equivalent inductance and equivalent capacitance values ​​of the underwater electric drive power supply. The actual output voltage after adjustment, the target output voltage under the current operating condition, and the PID parameters under the previous operating condition are obtained. The PID parameters include proportional parameters, integral parameters, and derivative parameters. Calculate the deviation e between the target output voltage and the actual output voltage. When the absolute value of the deviation is greater than a preset deviation threshold... The system employs an integral separation strategy, controlling the output voltage through proportional and derivative parameters. The voltage is maintained when the absolute value of the deviation is less than or equal to a preset deviation threshold. The system employs an integral control strategy, controlling the output voltage through proportional, integral, and derivative parameters.

[0017] The beneficial effects of this invention are: 1. Wide range and high precision adjustable resonant parameters: The inductor and capacitor each adopt a binary weighted capacitor array independently, achieving the most equivalent parameter combinations with the fewest MOS switching devices. Both the resonant inductor and resonant capacitor can be discretely adjusted over a wide range, with high tuning accuracy and a wide power range coverage, which can accurately match the resonant requirements of electric drives with different power.

[0018] 2. Uniform topology for bidirectional operation, simple and reliable structure: Adopting a full-bridge symmetrical CLLC topology, forward power supply and reverse feedback do not require switching hardware circuits. The optimal bidirectional operating point can be adapted by simply adjusting the parameters, reducing the number of components, reducing complexity, improving power density and reliability, and meeting the stringent requirements of underwater sealing, miniaturization, and high reliability.

[0019] 3. Divided switching, fast dynamic response, and low loss: The inductor array is divided into polarities for switching according to the load range (small step size for light load, large step size for heavy load), and the capacitor array is finely tuned according to the voltage deviation. The dual arrays work together to quickly lock the optimal resonant point, responding rapidly to sudden load changes, effectively maintaining soft switching state, and reducing switching and conduction losses.

[0020] 4. Good resistance to environmental interference and long-term stability: The dual-tuned array can compensate for the device parameter drift caused by temperature and water pressure in real time, suppress the influence of temperature drift and pressure drift on resonance characteristics, maintain resonance stability in a wide temperature and high pressure deep sea environment, and avoid efficiency reduction and abnormal operation caused by parameter drift. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the circuit structure of the bidirectional intelligent tuned power supply system of the present invention; Figure 2 This is a schematic diagram of the circuit structure of the first resonant capacitor bank of the present invention; Figure 3This is a schematic diagram of the circuit structure of the first resonant inductor group of the present invention; Figure 4 This is a flowchart of the PID algorithm of the present invention; Figure 5 This is a flowchart illustrating an adaptive control method for an underwater electric drive power supply according to the present invention.

[0022] Explanation of reference numerals in the attached diagram: 1. Input circuit; 2. First resonant circuit; 3. Transformer; 4. Second resonant circuit; 5. Output circuit; 6. First inductor; 7. First capacitor; 8. Second inductor; 9. First switch; 10. Second switch; 11. Third switch; 12. Fourth switch; 13. First resonant capacitor bank; 14. First resonant inductor bank; 15. Second resonant capacitor bank; 16. Second resonant inductor bank; 17. Fifth switch; 18. Sixth switch; 19. Seventh switch; 20. Eighth switch; 21. Third inductor; 22. Second capacitor; 23. Fourth inductor. Detailed Implementation

[0023] A bidirectional intelligent tuned power supply system for underwater equipment, such as Figure 1 As shown, the present invention includes: The input circuit 1, the first resonant circuit 2, the transformer 3, the second resonant circuit 4, and the output circuit 5 are connected in sequence. The first resonant circuit 2 and the second resonant circuit 4 have the same structure. The first resonant circuit 2 includes a first switch 9, a second switch 10, a third switch 11, a fourth switch 12, a first resonant capacitor group 13, and a first resonant inductor group 14. The drain of the first switching transistor 9 is connected to the drain of the second switching transistor 10. The source of the third switching transistor 11 is connected to the source of the fourth switching transistor 12. The source of the first switching transistor 9 is connected to the drain of the third switching transistor 11. The source of the second switching transistor 10 is connected to the drain of the fourth switching transistor 12. The drain of the fourth switching transistor 12 is connected to one end of the first resonant capacitor group 13. The other end of the first resonant capacitor group 13 is connected to the first resonant inductor group 14. The first resonant inductor group 14 is connected to the primary side of the transformer 3.

[0024] Specifically, the second resonant circuit 4 includes a fifth switch 17, a sixth switch 18, a seventh switch 19, an eighth switch 20, a second resonant capacitor group 15, and a second resonant inductor group 16.

[0025] The drain of the fifth switch transistor 17 is connected to the drain of the sixth switch transistor 18, the source of the seventh switch transistor 19 is connected to the source of the eighth switch transistor 20, the source of the fifth switch transistor 17 is connected to the drain of the seventh switch transistor 19, the source of the sixth switch transistor 18 is connected to the drain of the eighth switch transistor 20, the drain of the eighth switch transistor 20 is connected to one end of the second resonant capacitor group 15, the other end of the second resonant capacitor group 15 is connected to the second resonant inductor group 16, and the second resonant inductor group 16 is connected to the secondary side of the transformer 3.

[0026] Specifically, the circuit structures of the first resonant capacitor group 13 and the second resonant capacitor group 15 are the same, and the circuit structures of the first resonant inductor group 14 and the second resonant inductor group 16 are the same. Specifically, the first switch 9, the second switch 10, the third switch 11, and the fourth switch 12 are all MOSFETs.

[0027] like Figure 2 As shown, the first resonant capacitor group 13 includes: Several capacitors with different capacitance values ​​are given, and the capacitance values ​​of these capacitors satisfy the following relationship:

[0028] in, Here, m is the base capacitance value, and m is the number of switched capacitor branches in the resonant capacitor bank. Let be the capacitance of the m-th capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET.

[0029] Specifically, the capacitance value is adjusted by controlling the switching on and off of the MOSFET. The formula for calculating the equivalent capacitance is as follows: ,in, To disconnect the total capacitance value corresponding to the switch, continuous wide-range adjustment of the capacitance value is achieved. It is the main resonant capacitor.

[0030] The capacitor autotuning switched capacitor array also adopts a binary weight design, consisting of multiple capacitors with different binary weight values. and the corresponding switch Composition: Each capacitor is connected in parallel with its corresponding switch, and the entire assembly is connected in series in the main resonant capacitor C branch. By controlling the on / off state of the switch, capacitors with different weights are connected to the resonant cavity, thereby changing the total capacitance value, which can achieve... Equivalent capacitance regulation ( m (The number of capacitor switch branches) forms a two-dimensional collaborative tuning system with the binary weight array on the inductor side, which greatly improves the tuning accuracy and range.

[0031] Calculation method for capacitor adjustment amount: Capacitor adjustment amount With voltage deviation and voltage deviation change rate Related. The specific calculation method is as follows: ,in and For example, coefficients determined based on actual testing. ， .

[0032] The impact of capacitor adjustment under different power electric drives and light load conditions: Light load conditions (light load on low-power electric drives or light load on high-power electric drives): Under light load, if the output voltage is high and shows an upward trend ( and ), calculated according to the above formula A negative value indicates a decrease in capacitance; in this case, the capacitor with the smaller weight is disconnected first. Ca 1 =1C a Ca 2 =2C a For the corresponding switch, slightly reduce the equivalent capacitance value. Reducing the capacitance value will increase the resonant frequency, which not only meets the power supply characteristics requirements of low-power electric drives under light loads, but also helps to reduce the effective current value, reduce conduction losses, and improve light-load efficiency. Conversely, if the output voltage is low and trending downwards, increase the capacitance value to lower the resonant frequency, maintain a stable power supply output, and meet the needs of low-power electric drives under this operating condition.

[0033] Heavy load conditions (high-power electric drive at full or near full load): Under heavy load, if the output voltage is high and rising, reduce the capacitor value. In this case, prioritize disconnecting the large-weight capacitor. Ca 8 =8C a For switches corresponding to (and above), quickly reduce the equivalent capacitance value. This will increase the resonant frequency, enhance the energy storage capacity of the resonant circuit, and help the power supply better cope with the heavy load demands of high-power electric drives, maintaining stable output voltage. If the output voltage is low and drops, increase the capacitance value, reduce the resonant frequency, and enable the resonant circuit to provide greater current, enhancing the power supply's ability to handle high-power electric drives.

[0034] Sudden Changes in Operating Conditions and Braking Feedback: When the load or voltage changes rapidly (such as when an underwater electric drive switches from cruising to heavy-load propulsion or enters braking feedback mode), the control module directly selects a combination of multiple binary capacitors (small-weighted + large-weighted capacitors are switched in tandem) based on the comprehensive deviation. This achieves large-step adjustment of the equivalent capacitance, which, together with inductor tuning, quickly locks the optimal operating point, avoids soft switching loss, and ensures stability during operating condition switching.

[0035] like Figure 3As shown, the first resonant inductor group 14 includes: Several capacitors with different capacitance values ​​are connected to a resonant inductor. The capacitance values ​​of the different capacitors satisfy the following relationship:

[0036] in, Where n is the minimum capacitance value, and n is the number of switched capacitor branches in the resonant inductor group. Let n be the capacitance of the nth capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET. Specifically, the capacitance value is adjusted by controlling the switching on and off of the MOSFET. The formula for calculating the equivalent capacitance is as follows: ,in, To disconnect the total capacitance value corresponding to the switch, continuous wide-range adjustment of the capacitance value is achieved. The main resonant capacitor, through binary weighting design, only requires... n A single switch can achieve this. A combination of equivalent sensing values ​​is used to achieve the widest adjustment range with the fewest components.

[0037] By using a binary-weighted capacitor array in conjunction with the main resonant inductor, a wide-range, high-precision discrete adjustment of the inductance value can be achieved. In this scheme, the capacitor array of the inductor tuning branch adopts a binary-weighted design, with the capacitance values ​​of each capacitor arranged in ascending order of powers of 2, for example... , , ..., ,in, As the base capacitor, each capacitor is connected in series with a high-speed MOS switch, and the entire series is connected in parallel with the main resonant inductor. L At both ends, by using different combinations of on / off switches, one can obtain... equivalent inductance value ( n To achieve the design goal of "minimum number of components and widest adjustment range" (in terms of the number of switched capacitor branches), and to meet the stringent requirements of miniaturization and high reliability of underwater equipment.

[0038] Real-time monitoring of power supply output voltage Load current Based on key parameters such as resonant frequency deviation and switching transistor window, and combined with the characteristics of binary weighted capacitor arrays, the following proprietary inductor adjustment strategies are formulated for different power drives and light / heavy load conditions: Light load range (corresponding to light load conditions for low-power or high-power electric drives) ), Rated current value: Within this range, the core objective is to adapt to low-power electric drives and improve efficiency under light loads. When the load current increases, the control module will adjust the response based on the rate of increase in the load current. This determines the inductor adjustment amount, and prioritizes switching on and off low-weight capacitors. , ), fine-tune the equivalent inductance with small steps: if , To determine the rate of change of current, the capacitors are closed sequentially. and The corresponding switch causes the inductance value to increase in small steps, with each decrease in inductance value being... This not only helps adapt to the changing load requirements of low-power electric drives, but also reduces the effective value of the current, decreases conduction losses, and improves light-load efficiency by optimizing the resonant parameters.

[0039] When the load current decreases, if Then, the switches corresponding to the closed small-weight capacitors are disconnected in sequence, so that the inductance value increases at the same pace.

[0040] Medium load section ( ): In this range, the primary objective is to maintain the stability of the resonant state, ensuring efficient power supply operation to meet the demands of electric drives with varying power ratings under medium load. When the load current increases and When the current inductance value is Then choose a closed-loop, medium-weighted capacitor ( = The switch increases the inductance value to... When the load current decreases and When, disconnect the medium-weight capacitor ( = The switch reduces the inductance value to ,in, For transient inductance, This is the adjustment amount for the reference inductance.

[0041] Heavy load range (corresponding to high-power electric drives at full load or near full load) ): Under heavy load conditions, the core objective is to adapt to the high power demands of high-power electric drives and enhance the power supply's load-carrying capacity. When the load current increases and At that time, rapidly increase the inductance value. If the current inductance value is... Then, by closing and rapidly switching high-weight capacitors (C=8C and above), the inductance value is increased to... This enhances the power supply's load-carrying capacity. When the load current decreases and At that time, disconnect the corresponding high-weight capacitor switch, causing the inductance value to decrease rapidly. .

[0042] All capacitors are connected to the resonant inductor.

[0043] The input circuit 1 includes: The first inductor 6, the first capacitor 7, and the second inductor 8 are connected in sequence. One end of the first capacitor 7 is connected to the drain of the first switching transistor 9, and one end of the second capacitor 22 is connected to the source of the third switching transistor 11. The first inductor 6 is connected to the positive terminal of the power supply, and the second inductor 8 is connected to the negative terminal of the power supply.

[0044] The output circuit 5 includes: The third inductor 21, the second capacitor 22, and the fourth inductor 23 are connected in sequence; The two ends of the second capacitor 22 are connected to the second resonant circuit 4.

[0045] Specifically, one end of the second capacitor 22 is connected to the drain of the fifth switch 17, and the other end of the second capacitor 22 is connected to the source of the seventh switch 19. Forward power transfer (normal operating mode): When the underwater equipment is in normal operating mode and needs to obtain energy from the power supply, the bidirectional switching transistors (from the first to the eighth transistor) transmit electrical energy from the input side to the output side under the action of control signals, using specific combinations of on and off states. At this time, the input circuit sends the pre-processed DC power to the bidirectional CLLC resonant circuit. The control module, through real-time monitoring of parameters such as load current and output voltage, uses automatic tuning technology to tune the inductor and capacitor to the optimal parameters for the current operating condition, achieving ZVS conduction and ZCS turn-off of the full-bridge switching transistors, completing efficient power conversion. Subsequently, the electrical energy is transformed by a transformer and then filtered and regulated by the output circuit to provide stable DC power to the underwater equipment.

[0046] Reverse power transfer (energy feedback mode): When underwater equipment is in energy feedback mode, such as when excess electrical energy is generated during motor braking, the control logic of the bidirectional switch changes. The detection circuit monitors the energy feedback signal in real time, and the control module adjusts the on and off states of the bidirectional switch based on this signal, enabling reverse energy transmission, i.e., flowing from the output side to the input side. During this process, automatic tuning technology plays a simultaneous role, tuning the resonant parameters to the optimal operating point for the reverse condition. This ensures that the switch maintains soft-switching operation during the reverse transmission process, effectively recovering the fed-back electrical energy to the power input terminal, thus achieving energy recovery and reuse.

[0047] Specifically, during forward operation, the primary-side switches 9 and 12 are complementary to the secondary switches 10 and 11. First, switches 9 and 12 conduct, and the current flows through switches 9, the resonant inductor, the magnetizing inductor, the resonant capacitor, and switches 12 to form a circuit, generating a sinusoidal alternating current. After half a cycle, switches 10 and 11 conduct, and the current reverses direction.

[0048] Secondary-side switching transistors: The secondary side is a full-wave rectifier. During the positive half-cycle of the secondary-side voltage, the fifth switch transistor 17 and the eighth switch transistor 20 are turned on, and the current supplies power to the equipment through the fifth switch transistor 17 and returns to the transformer 3 through the eighth switch transistor 20; during the negative half-cycle, the sixth switch transistor 18 and the seventh switch transistor 19 are turned on, and the current supplies power in the reverse direction.

[0049] In reverse operation, the primary-side switches 9 and 12 remain complementary to the secondary-side switches 10 and 11, but the control signal is adjusted. First, switches 10 and 11 conduct to receive secondary-side power; after half a cycle, switches 9 and 12 conduct to change the current direction, adapting to reverse transmission.

[0050] Secondary-side switches: The conduction sequence is the opposite of the forward sequence. During the positive half-cycle of the secondary voltage, switches 18 (sixth) and 19 (seventh) conduct to inject energy; during the negative half-cycle, switches 17 (fifth) and 20 (eighth) conduct to continuously feed energy back to the primary power supply.

[0051] In terms of program design, the direction of energy flow is determined by detecting the voltage and current direction across the bidirectional switching transistor, and a flag is set to indicate the flow direction. The corresponding drive control function is called based on the value of the flag, while the current and voltage of the bidirectional switching transistor are monitored in real time. If overcurrent or overvoltage occurs, protective measures are taken immediately, such as shutting down the drive signal and recording the fault information.

[0052] Resonance frequency formula: Resonance frequency of CLLC resonant topology Mainly composed of resonant inductors and capacitor The decision is made using the following formula: In this invention, the automatic tuning technology works by changing the inductance. and capacitor The value, directly to and This has an effect, thus changing the resonant frequency. For example, when the inductor automatically tunes... If the capacitance remains constant when the capacitance increases, As it increases, according to the above formula, the resonant frequency... It will decrease; conversely, when the capacitor automatically tunes... When decreasing, Decrease, resonant frequency This will increase. This adjustment of the resonant frequency can not only adapt to the power output characteristics requirements of electric drives with different power ratings, but also optimize power efficiency under light loads.

[0053] Efficiency Formula Derivation: Power Supply Efficiency With output power and input power Related, that is In a CLLC resonant circuit, the output power... With resonant current Output voltage Factors such as input power Then with input voltage Input current And so on. Circuit analysis reveals that the resonant current... With resonant frequency ,inductance ,capacitance These parameters are closely related. Assuming the circuit operates ideally and neglecting some minor losses, when the resonant frequency... near power supply operating frequency At this time, the circuit impedance is at its minimum, the current transmission efficiency is at its maximum, and the output power is at its highest. Relatively large, input power Relatively small, power efficiency This allows for improvement. Automatic tuning technology changes the resonant frequency by adjusting the inductor and capacitor. To better match the power supply operating frequency. This system can meet the power output characteristics requirements of electric drives with different power ratings, while also improving the power supply efficiency under light loads. For example, under light load conditions, automatic tuning raises the resonant frequency to be closer to the power supply's operating frequency, reducing the effective current value and conduction losses, thereby improving power supply efficiency. Under heavy load conditions, adjusting the resonant parameters optimizes the resonant state, enhancing the power supply's adaptability to high-power electric drives.

[0054] The gates of the first switch transistor 9, the second switch transistor 10, the third switch transistor 11, and the fourth switch transistor 12 are connected to the pulse control circuit.

[0055] Specifically, the pulse control circuit of this application adopts a combination of PWM pulse width modulation and frequency modulation control to precisely control the conduction and turn-off of the bidirectional full-bridge MOSFET, and deeply coordinates with the automatic tuning technology to achieve soft switching under all operating conditions.

[0056] PWM Control Method: The drive circuit uses PWM (Pulse Width Modulation) control to control the on / off state of the MOSFET. The duty cycle of the PWM signal is adjusted according to the control output of the control module. For example, during automatic tuning, when the inductor or capacitor is adjusted, the duty cycle of the PWM signal will change accordingly to maintain the stable operation of the resonant circuit, adapt to different power drives, and ensure efficiency under light load. If the inductance value is increased to adapt to the heavy load requirements of a high-power drive, the duty cycle of the PWM signal may be appropriately increased to ensure stable output power, thus lengthening the MOSFET's on-time and increasing energy transfer. Under light load, PWM control and automatic tuning technology work together to reduce the effective current value by adjusting the duty cycle, thereby improving light load efficiency.

[0057] Frequency modulation control: In addition to PWM control, frequency modulation control is also employed. Under different operating conditions, the control module adjusts the frequency of the PWM signal based on the inductor and capacitor values ​​adjusted by automatic tuning, as well as the load requirements of different power drives. For example, under light load conditions, when the capacitor value decreases to increase the resonant frequency to adapt to the light load requirements of low-power drives, the frequency modulation control will correspondingly increase the frequency of the PWM signal, allowing the switching frequency of the MOSFET to better match the resonant frequency, further optimizing the light load efficiency of the power supply. Under heavy load conditions, if the inductor value is adjusted to enhance the load-carrying capacity of high-power drives, the frequency modulation control will adjust the PWM signal frequency according to the new combination of inductor and capacitor values, ensuring that the power supply can operate stably and efficiently under heavy loads, meeting the needs of high-power drives.

[0058] The power supply employs a combination of two control methods: PWM control and frequency modulation control work together and are closely integrated with automatic tuning technology. During operation, the control module dynamically adjusts the duty cycle and frequency of the PWM signal based on real-time monitored parameters such as output voltage and load current. This adapts to changes in inductance and capacitance values ​​caused by automatic tuning, enabling precise control of the MOSFETs. Consequently, the power supply operates efficiently and stably under various conditions, meeting the needs of different power drives while maintaining high efficiency under light loads.

[0059] Customized PID parameters are matched for different underwater working conditions, while the anti-interference capability is optimized, greatly improving the adjustment accuracy and stability.

[0060] An adaptive control method for an underwater electric drive power supply includes the following steps: Real-time data of the underwater electric drive power supply is collected, including output voltage, load current, and input voltage. Based on the real-time data, the current operating condition can be identified; Based on the real-time data, the comprehensive deviation is calculated, and the first resonant capacitor group and the first resonant inductor group are adjusted according to the comprehensive deviation to adjust the equivalent inductance and equivalent capacitance values ​​of the underwater electric drive power supply. The actual output voltage after adjustment, the target output voltage under the current operating condition, and the PID parameters under the previous operating condition are obtained. The PID parameters include proportional parameters, integral parameters, and derivative parameters. Calculate the deviation between the target output voltage and the actual output voltage. e When the absolute value of the deviation is greater than the preset deviation threshold The system employs an integral separation strategy, controlling the output voltage through proportional and derivative parameters. The voltage is maintained when the absolute value of the deviation is less than or equal to a preset deviation threshold. The system employs an integral control strategy, controlling the output voltage through proportional, integral, and derivative parameters.

[0061] Specifically as follows: Set the scaling factor Integral coefficient Differential coefficients The base value, while setting adaptive adjustment coefficients for different working conditions: Start-up conditions: It quickly establishes the output voltage and suppresses overshoot. The basic proportional coefficient, The basic integral coefficient, These are the basic differential coefficients.

[0062] Light load conditions: Improve steady-state accuracy and optimize light-load efficiency; Medium load condition: It balances response speed and steady-state accuracy; Heavy-duty operating conditions: ， ， This enhances load-carrying capacity and suppresses voltage drops; Reverse feedback operating condition: ， ， It adapts to the reverse energy flow characteristics to ensure feedback efficiency.

[0063] Based on the feedback control principle, by setting the target output voltage Compare it with the actual output voltage By comparison, the voltage deviation was obtained. At the same time, pay attention to the load current. Calculate the rate of change of . Taking load current into account Output voltage Input voltage Several parameters, such as inductance and capacitance, are used to adjust the values. Through analysis of extensive underwater operating data, the weight of each parameter is determined, such as the load current weight. Output voltage weighting Input voltage weighting Calculate the overall deviation. ,in 、 、 These are reference values ​​for load current, output voltage, and input voltage, respectively. These reference values ​​are set based on the power supply's rated parameters and actual application requirements. (Based on comprehensive deviation...) Determine the adjustment rules for inductors and capacitors, when At this time, increase the inductance and capacitance values, with the specific adjustment amount based on the preset adjustment coefficient. and Confirm inductance adjustment amount Capacitor adjustment amount Conversely, when When necessary, the inductor and capacitor values ​​are reduced. This comprehensive algorithm can fully consider various parameters of power supply operation and accurately adjust the inductor and capacitor to better adapt to the needs of electric drives with different power under various operating conditions, while optimizing power efficiency under light load.

[0064] The control algorithm employs an integral separation strategy: when ( For a pre-set deviation threshold, for example When the integral action is temporarily canceled, the deviation is quickly reduced solely by proportional and derivative control. At this point, the control quantity calculation formula becomes... ;when At that time, integral control is introduced to eliminate steady-state error, and a complete integral control is adopted. The computational control enables precise control of inductor and capacitor values, thus adapting to electric drives of varying power and optimizing efficiency under light loads. The algorithm flowchart is as follows: Figure 4 As shown.

[0065] This comprehensive algorithm can fully consider various parameters of power supply operation, precisely adjust inductors and capacitors to better adapt to the needs of electric drives with different power ratings under various operating conditions, and optimize power efficiency under light loads. The algorithm flowchart is shown below. Figure 5 As shown.

[0066] Specifically, the power supply can quickly adapt to the needs of electric drives with different power ratings under various underwater operating conditions. During equipment startup, it can quickly adjust to a suitable output state to meet the starting current requirements. Simultaneously, automatic tuning technology significantly improves the power supply's efficiency under light loads, substantially enhancing its adaptability and efficiency.

[0067] It achieves efficient energy transmission under all operating conditions, including forward power supply and reverse braking feedback, with reverse energy recovery efficiency improved by more than 30%, thereby increasing energy utilization. Enhance the overall endurance and braking control performance of underwater equipment to meet the frequent start-stop and speed adjustment requirements of underwater vehicles.

[0068] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0069] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. A bidirectional intelligent tuned power supply system for underwater equipment, characterized in that, include: The input circuit (1), the first resonant circuit (2), the transformer (3), the second resonant circuit (4), and the output circuit (5) are connected in sequence. The first resonant circuit (2) and the second resonant circuit (4) have the same structure. The first resonant circuit (2) includes a first switch (9), a second switch (10), a third switch (11), a fourth switch (12), a first resonant capacitor group (13), and a first resonant inductor group (14). The drain of the first switch (9) is connected to the drain of the second switch (10), the source of the third switch (11) is connected to the source of the fourth switch (12), the source of the first switch (9) is connected to the drain of the third switch (11), the source of the second switch (10) is connected to the drain of the fourth switch (12), the drain of the fourth switch (12) is connected to one end of the first resonant capacitor group (13), the other end of the first resonant capacitor group (13) is connected to the first resonant inductor group (14), and the first resonant inductor group (14) is connected to the transformer (3).

2. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The first resonant capacitor group (13) includes: Several capacitors with different capacitance values ​​are given, and the capacitance values ​​of these capacitors satisfy the following relationship: in, Here, m is the base capacitance value, and m is the number of switched capacitor branches in the resonant capacitor bank. Let be the capacitance of the m-th capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET.

3. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The first resonant inductor group (14) includes: Several capacitors with different capacitance values ​​are connected to a resonant inductor. The capacitance values ​​of the different capacitors satisfy the following relationship: in, Where n is the minimum capacitance value, and n is the number of switched capacitor branches in the resonant inductor group. Let n be the capacitance of the nth capacitor branch; The different capacitors are connected in parallel, and each capacitor is connected in series with a MOSFET.

4. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The input circuit (1) includes: The first inductor (6), the first capacitor (7), and the second inductor (8) are connected in sequence; One end of the first capacitor (7) is connected to the drain of the first switch (9), and the other end of the first capacitor (7) is connected to the source of the third switch (11). The first inductor (6) is connected to the positive terminal of the power supply, and the second inductor (8) is connected to the negative terminal of the power supply.

5. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The output circuit (5) includes: The third inductor (21), the second capacitor (22), and the fourth inductor (23) are connected in sequence; The two ends of the second capacitor (22) are connected to the second resonant circuit (4).

6. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The first switch (9), the second switch (10), the third switch (11), and the fourth switch (12) are all MOSFETs.

7. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 1, characterized in that, The gates of the first switch (9), the second switch (10), the third switch (11), and the fourth switch (12) are connected to the pulse control circuit.

8. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 4, characterized in that, The capacitance value is adjusted by turning the MOSFET on or off.

9. The bidirectional intelligent tuned power supply system for underwater equipment according to claim 5, characterized in that, The inductance value is adjusted by turning the MOSFET on or off.

10. An adaptive control method for an underwater electric drive power supply, applied to the bidirectional intelligent tuned power supply system for underwater equipment as described in any one of claims 1 to 9, characterized in that, include: Real-time data of the underwater electric drive power supply is collected, including output voltage, load current, and input voltage. Based on the real-time data, the current operating condition can be identified; Based on the real-time data, the comprehensive deviation is calculated, and the first resonant capacitor group and the first resonant inductor group are adjusted according to the comprehensive deviation to adjust the equivalent inductance and equivalent capacitance values ​​of the underwater electric drive power supply. The actual output voltage after adjustment, the target output voltage under the current operating condition, and the PID parameters under the previous operating condition are obtained. The PID parameters include proportional parameters, integral parameters, and derivative parameters. Calculate the deviation e between the target output voltage and the actual output voltage. When the absolute value of the deviation is greater than a preset deviation threshold... The system employs an integral separation strategy, controlling the output voltage through proportional and derivative parameters. The voltage is maintained when the absolute value of the deviation is less than or equal to a preset deviation threshold. The system employs an integral control strategy, controlling the output voltage through proportional, integral, and derivative parameters.

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