A new energy multi-port converter control method adaptive to full wind speed

Abstract

The application discloses a new energy multi-port converter control method suitable for full wind speed, which comprises the following steps: step 1, determining the working mode of a wind power generation port under different wind speeds, and measuring the output voltage threshold of a rectifier circuit corresponding to each wind speed mode; step 2, determining the state of a battery in a battery port and the state of a load port; step 3, determining the current threshold of a switch tube according to the maximum current stress that the switch tube can bear; step 4, based on the factors determined in steps 1-3, different system working conditions are divided, and the control conditions between the system working conditions are determined; step 5, according to the system working conditions and the control conditions, a state diagram covering all working conditions is drawn, and a control instruction is generated according to the state diagram, so that the converter control in the full wind speed range is realized. The application defines a complete set of system working conditions and switching logic, so that the energy flow is optimized in the full wind speed range, and the overall performance of the system is improved.

Description

Technical Field

[0001] This invention relates to the field of new energy power electronics technology, and in particular to a control method for a new energy multi-port converter that adapts to all wind speeds. Background Technology

[0002] With the growing demand for renewable energy, power converters (multi-port converters) that can integrate multiple distributed power sources (such as wind and solar power) and energy storage units are attracting increasing attention due to their compact structure, cost-effectiveness, and flexible operating modes. As an important renewable energy source, the efficient and reliable utilization of wind energy is crucial for small-scale off-grid or grid-connected systems.

[0003] In existing technologies, small wind power generation systems typically employ a simple rectification process followed by direct connection to the battery or management via a single DC / DC converter. This approach generally suffers from the following shortcomings across the entire wind speed range (from cut-in wind speed to cut-out wind speed): 1. Low wind energy capture efficiency, failing to optimally switch between multiple modes such as maximum power point tracking (MPPT), direct connection, and load shedding based on wind speed changes; 2. Insufficient consideration of system operating conditions (such as turbine power generation status, battery charging / discharging status, and load status), resulting in ambiguous condition classifications, complex control logic, and potential conflicts; 3. Failure to systematically incorporate current stress protection systems for critical components (such as switching transistors) into mode switching decisions, potentially affecting system reliability. Summary of the Invention

[0004] The purpose of this invention is to provide a control method for a new energy multi-port converter that adapts to all wind speeds. This invention systematically integrates the wind turbine operating modes, energy storage battery status, load status, and stress limitations of power devices to define a complete set of system operating conditions and switching logic, thereby optimizing energy flow across the entire wind speed range and improving overall system performance.

[0005] The technical solution of this invention: A control method for a new energy multi-port converter adaptable to all wind speeds, wherein the new energy multi-port converter includes a wind power generation port, a photovoltaic port, a battery port, and a load port, and the control method includes the following sequential steps:

[0006] Step 1: Determine the operating mode of the wind power generation port under different wind speeds, and measure the output voltage threshold of the rectifier circuit corresponding to each wind speed mode under no-load conditions;

[0007] Step 2: Determine the three states of the battery in the battery port: charging, discharging, and low charge, and the two states of the load port: loaded and unloaded.

[0008] Step 3: Determine the current threshold based on the maximum current stress that the switching transistor can withstand;

[0009] Step 4: Based on the factors determined in Steps 1-3, different system operating conditions are identified, and the control conditions between each system operating condition are determined.

[0010] Step 5: Based on the system operating conditions and control conditions, draw a state diagram covering all operating conditions, and generate control commands based on the state diagram to realize converter control across the entire wind speed range.

[0011] In the above-mentioned new energy multi-port converter control method adapted to all wind speeds, the operating modes in step 1 include: low wind speed no power generation mode, medium wind speed power generation mode via Boost boost circuit, high wind speed direct power generation mode, and ultra-high wind speed short-circuit unloading mode.

[0012] The output voltage threshold of the rectifier circuit includes a first voltage threshold, a second voltage threshold, and a third voltage threshold, and satisfies the following:

[0013] When the output voltage of the rectifier circuit is less than the first voltage threshold, the wind power generation port operates in the low wind speed no power generation mode.

[0014] When the output voltage of the rectifier circuit is between the first voltage threshold and the second voltage threshold, the wind power generation port operates in the medium wind speed power generation mode via the Boost boost circuit.

[0015] When the output voltage of the rectifier circuit is between the second voltage threshold and the third voltage threshold, the wind power generation port operates in the high wind speed direct power generation mode.

[0016] When the output voltage of the rectifier circuit is greater than or equal to the third voltage threshold, the wind power generation port operates in the ultra-high wind speed short-circuit unloading mode.

[0017] In the aforementioned new energy multi-port converter control method adapted to all wind speeds, the three states of the battery in step 2 are characterized by the DC bus voltage:

[0018] When the DC bus voltage is in the first bus voltage range, the battery port state of charge is between 0% and 5%, which is defined as a depleted state.

[0019] When the DC bus voltage is in the second bus voltage range, the battery port state of charge is between 5% and 95%, which is defined as the normal charging and discharging range.

[0020] When the DC bus voltage is in the third bus voltage range, the battery port state of charge is between 95% and 100%, which is defined as the fully charged state.

[0021] In the aforementioned new energy multi-port converter control method adapted to all wind speeds, in step 3, the current threshold is used to determine the control conditions between the power generation mode via the Boost circuit at medium wind speed and the direct power generation mode at high wind speed.

[0022] When the switching current of the medium wind speed power generation mode via the Boost circuit is greater than the sum of its maximum current stress and hysteresis margin, or when the ratio of the rectifier circuit output voltage to the DC bus voltage is greater than the preset upper limit of the ratio, the power generation mode via the Boost circuit for medium wind speed is controlled to the direct power generation mode for high wind speed.

[0023] When the ratio of the rectifier circuit output voltage to the DC bus voltage is less than the preset lower limit, the system switches from high wind speed direct power generation mode to medium wind speed power generation mode via the Boost circuit.

[0024] In the aforementioned control method for new energy multi-port converters adaptable to all wind speeds, step 4 specifically describes the system operating conditions as follows:

[0025] Operating condition 1: Wind turbine generates electricity, battery charges, load is applied;

[0026] Operating Condition 2: Wind turbine generates electricity, battery discharges, load is applied;

[0027] Operating condition 3: Wind turbine generating electricity, battery charging, load unloaded;

[0028] Operating condition 4: The wind turbine is not generating electricity, the battery is discharging, and the load is under load;

[0029] Operating Condition 5: The wind turbine is not generating electricity, the battery is depleted, and the load is unloaded.

[0030] The aforementioned control method for a new energy multi-port converter adapted to all wind speeds includes the following switching control conditions between system operating conditions in step 4:

[0031] The passive control between operating condition 1 and operating condition 2 is based on the relationship between the power generated by the wind turbine and the power consumed by the load.

[0032] The operation between operating condition 1 and operating condition 3 is actively controlled based on the load switching on and off actions. When the load is switched on, the wind turbine power generation must be greater than the load power consumption.

[0033] The control between operating condition 1 and operating condition 4 is actively adjusted based on whether the DC bus voltage, DC bus current, or rectifier circuit output voltage exceeds a preset threshold.

[0034] The control between operating conditions 2 and 3 is based on either active control during load shedding or passive control when the DC bus voltage is lower than the battery depletion threshold.

[0035] Between operating conditions 3 and 2, active control is performed based on the load switching action, while passive control is performed when the wind turbine's power generation is not greater than the load's power consumption.

[0036] The operation between Condition 4 and Condition 5 is passively controlled when the DC bus voltage is lower than the battery depletion threshold.

[0037] The aforementioned control method for a new energy multi-port converter adaptable to all wind speeds, wherein the specific switching conditions between operating condition 1 and operating condition 2 are as follows:

[0038] When the wind turbine's power generation exceeds the load's power consumption, the system switches from operating condition 1 to operating condition 2;

[0039] When the wind turbine's power generation is less than the load's power consumption, the system switches from operating condition 1 to operating condition 2.

[0040] The aforementioned control method for a new energy multi-port converter adapted to all wind speeds, wherein the active control condition for switching from operating condition 1 to operating condition 4 is specifically as follows: the DC bus voltage at the battery port is greater than the sum of the full-charge voltage threshold and the voltage margin, or the DC current at the load port is greater than the maximum allowable current of the switching transistor, or the rectified voltage at the wind power generation port is less than the difference between the low wind speed start-up voltage threshold and the voltage margin.

[0041] The active control conditions for switching from operating condition 4 to operating condition 1 are as follows: the ratio of the rectified voltage at the wind power generation port to the DC bus voltage at the battery port is greater than the sum of the switching constant and the voltage margin, and the DC bus voltage at the battery port is less than the difference between the maximum withstand voltage threshold and the voltage margin; or the rectified voltage at the wind power generation port is greater than the sum of the low wind speed start-up voltage threshold and the voltage margin.

[0042] The aforementioned control method for new energy multi-port converters adapted to all wind speeds, wherein active control refers to the controller actively initiating switching actions or mode control commands; and passive control refers to the system operating state transition caused by the natural satisfaction of external power or voltage conditions, with the controller only performing detection and following.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. This invention characterizes wind speed using the more easily measurable rectified output voltage, and, in conjunction with the stress of the switching transistor, rationally defines four wind turbine operating modes across the entire wind speed range, enabling the wind turbine to deliver electrical energy at maximum power within the maximum wind speed range under the premise of reliable operation.

[0045] 2. This invention comprehensively considers wind speed, switch stress, battery port status, load port status, and photovoltaic port status, and lists in detail various actual operating conditions of the multi-port converter, and provides clear switching conditions between all actual operating conditions, reducing the risk of the system entering an unexpected operating state under complex wind speed and load changes.

[0046] 3. By distinguishing between active control and passive control, the responsibilities of the controller are clarified, the control logic is simplified, and the reliability and feasibility of the system in long-term operation are improved. Attached Figure Description

[0047] Figure 1 This is a schematic flowchart of the method of the present invention;

[0048] Figure 2 For new energy multi-port converter topology;

[0049] Figure 3 State diagram for control method of new energy multi-port converter system;

[0050] Figure 4 This is a waveform diagram showing the switching of the wind turbine's operating modes. Detailed Implementation

[0051] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0052] Example: A control method for a new energy multi-port converter adaptable to all wind speeds, wherein the new energy multi-port converter includes the following ports and circuits:

[0053] Wind power generation port (wind turbine): It consists of wind turbine blades, main shaft and permanent magnet synchronous generator (PMSG). The three-phase output terminal of PMSG is connected to the AC input terminal of three-phase uncontrolled rectifier circuit.

[0054] The rectifier circuit's DC output is connected to the input of the Boost converter and one end of the bypass switch Q1. The Boost converter consists of an inductor, a switching transistor Q2, and a diode. Its output and the other end of the bypass switch Q1 are both connected to the positive terminal of the DC bus.

[0055] Battery port: The battery is connected to the DC bus via switch Q5, which has an anti-parallel diode for controlling the battery charging circuit.

[0056] Load port: The load is directly connected in parallel between the positive and negative terminals of the DC bus.

[0057] Photovoltaic port: The photovoltaic module is connected to the DC bus via its matching DC / DC converter (not shown in detail in the figure).

[0058] Unloading resistor: The unloading resistor is connected to the DC output terminal of the rectifier circuit through the switching transistor Q1 (i.e., bypass switch, which operates in PWM mode in unloading mode) to consume excess energy at ultra-high wind speeds.

[0059] Controller: The controller acquires the output voltage V of the rectifier circuit. dc1 DC bus voltage V dc2 Boost switch current I Q2 DC bus current I dc2The system outputs PWM drive signals to control the switching transistors Q1, Q2, Q5, etc., to achieve full-condition management.

[0060] After rectification, wind power can be fed into the DC bus via either a boost converter (Q2 operating) or a bypass connection (Q1 closed). The energy storage battery and load are directly connected to the DC bus. Photovoltaic power is fed into the DC bus via a DC / DC converter. At ultra-high wind speeds, the unloading resistor uses PWM control of Q1 to short-circuit and unload the rectified output. The DC bus voltage is clamped by the energy storage battery voltage and serves as the system's voltage reference.

[0061] The control method includes the following steps:

[0062] Step 1: Determine the operating modes of the wind turbine at different wind speeds, and measure the output voltage threshold of the rectifier circuit corresponding to each wind speed mode under no-load conditions.

[0063] In this step, such as Figure 2 As shown, the four operating modes of the PMSG (Permanent Magnet Synchronous Motor) at different wind speeds are: no power generation at low wind speed, power generation after boosting at medium wind speed, direct power generation at high wind speed, and short-circuit unloading at ultra-high wind speed. Power generation includes boosting at medium wind speed and direct power generation at high wind speed. No power generation includes no power supply at low wind speed and unloading at ultra-high wind speed.

[0064] The output voltage of the rectifier circuit under different wind speeds was measured under no-load conditions, and the rectifier voltage threshold under different wind speed modes of the wind turbine was obtained.

[0065] Based on the output voltage V of the rectifier circuit measured at different wind speeds under no-load conditions... dc1 Determine the voltage value corresponding to each wind speed node:

[0066] f:V dc1_n → v wind_n ;

[0067] Among them, v wind The voltage represents wind speed, and n represents the critical points for each wind speed. n = 1, 2, 3 represent the critical points between low and medium wind speeds, medium and high wind speeds, and high and ultra-high wind speeds, respectively, which are also the first voltage threshold V. dc1_1 Second voltage threshold V dc1_2 and the third voltage threshold V dc1_3 :

[0068] When 0 < V dc1 < V dc1_1 At this time, the wind turbine operates in a low wind speed, non-power generation mode and does not generate electricity;

[0069] When V dc1_1 ≤ V dc1 < V dc1_2 At this time, the wind turbine operates in the medium wind speed generation mode via the Boost circuit. The wind turbine generates electricity after being boosted by the Boost circuit, and the Boost circuit performs the Maximum Power Point Tracking (MPPT) function.

[0070] When V dc1_2 ≤ V dc1 < V dc1_3 At this time, the wind turbine operates in the high wind speed direct power generation mode, and the bypass Boost circuit generates power directly;

[0071] When V dc1 ≥ V dc1_3 At this time, the wind turbine operates in the ultra-high wind speed short-circuit unloading mode and enters the short-circuit unloading state.

[0072] Step 2: Determine the three states of the battery in the battery port: charging, discharging, and low charge, as well as the two states of the load port: loaded and unloaded.

[0073] In this step, "battery depleted" means the battery is completely discharged and can no longer discharge. The battery terminal uses... Figure 2 The switching transistor Q5 controls the battery. Because the switching transistor has an anti-parallel diode, it can only control whether the battery is charging, but not whether it is discharging. The battery's State of Charge (SoC) is expressed using the DC bus voltage V. dc2 Size representation:

[0074] When the DC bus voltage is in the first bus voltage range (V dc2_1 ≤ V dc2 < V dc2_2 When 0% ≤ SoC <5% is defined as a state of low power;

[0075] When the DC bus voltage is in the second bus voltage range (V dc2_2 ≤ V dc2 < V dc2_3 When 5% ≤ SoC < 95%; defined as the normal charging and discharging range;

[0076] When the DC bus voltage is in the third bus voltage range (V dc2_3 ≤ V dc2 ≤ V dc2_4 When 95% ≤ SoC ≤ 100% is defined as fully charged.

[0077] Among them, the first bus voltage range (V dc2_1 to V dc2_2 ), the second bus voltage range (V dc2_2 to V dc2_3 ), and the third bus voltage range (V dc2_3 to V dc2_4 ) are all preset in advance, that is, V dc2_1 , V dc2_2 , V dc2_3 , and V dc2_4 are four set voltage reference thresholds.

[0078] In this step, two states of the load port are considered. No load is represented by "load = 0", and load is represented by "load > 0"; the two states of the photovoltaic port are photovoltaic power generation and no photovoltaic power generation.

[0079] Step 3: Determine its current threshold according to the maximum current stress that the switching tube can withstand.

[0080] In this step, as Figure 2 shown, when the wind speed is medium, the wind turbine generates electricity after being boosted by the Boost circuit. The Boost circuit has the MPPT function. Therefore, the wind speed range of medium wind speed is expanded as much as possible so that the converter system can generate electricity at the maximum power within the maximum wind speed range. At this time, according to the maximum current stress that the Boost switching tube ( Figure 2 Q2 in) can withstand, its current threshold is determined and used as the judgment condition for whether to switch to the high wind speed mode:

[0081] When the current of the switching tube in the power generation mode of the Boost boost circuit at medium wind speed is greater than the sum of its maximum current stress and the hysteresis margin, or when the ratio of the output voltage of the rectifier circuit to the DC bus voltage is greater than the preset ratio upper limit, control from the power generation mode of the Boost boost circuit at medium wind speed to the direct power generation mode at high wind speed, that is, V dc1 / V dc2 > x + Δx or I Q2 > I Q2,max + ΔI.

[0082] When the ratio of the output voltage of the rectifier circuit to the DC bus voltage is less than the preset ratio lower limit, control from the direct power generation mode at high wind speed to the power generation mode of the Boost boost circuit at medium wind speed, that is, V dc1 / V dc2 < x - Δx. Among them, x is a constant between 0 and 1, and Δx is the margin of hysteresis comparison.

[0083] Step 4: Based on the factors determined in Steps 1-3, different system operating conditions are divided, and the control conditions between the system operating conditions are determined;

[0084] Operating condition 1: Wind turbine generates electricity, battery charges, load is applied;

[0085] Operating Condition 2: Wind turbine generates electricity, battery discharges, load is applied;

[0086] Operating condition 3: Wind turbine generating electricity, battery charging, load unloaded;

[0087] Operating condition 4: The wind turbine is not generating electricity, the battery is discharging, and the load is under load;

[0088] Operating Condition 5: The wind turbine is not generating electricity, the battery is depleted, and the load is unloaded.

[0089] Other operating conditions consisting of other wind turbine, battery, and load states, such as "wind turbine not generating electricity, battery charging, load with 0 load," are not valid and can be excluded.

[0090] The optimal switching conditions between various system operating conditions are then summarized and simplified.

[0091] Condition for switching from operating condition 1 to operating condition 2: P wind > P load (Passive control);

[0092] Conditions for switching from operating condition 2 to operating condition 1: P wind ≤ P load (Passive control);

[0093] Conditions for switching from operating condition 1 to operating condition 3: load shedding (active control);

[0094] Conditions for switching from operating condition 3 to operating condition 1: Load is switched on (active control) and P wind > P load (Passive control);

[0095] Conditions for switching from operating condition 1 to operating condition 4: V dc2 >V dc2_3 +ΔV (active control) or I dc2 >I dc2,max (Active control) or V dc1 <V dc1_1 -ΔV (active control);

[0096] Conditions for switching from operating condition 4 to operating condition 1: V dc1 / V dc2 >x+Δx and V dc2 <V dc2_4 -ΔV (active control) or V dc1 >V dc1_1 +ΔV (active control);

[0097] Conditions for switching from operating condition 2 to operating condition 3: load shedding (active control) or V dc2 <Vdc2_2 (Passive control);

[0098] Conditions for switching from operating condition 3 to operating condition 2: Load is switched on (active control) and P wind ≤ P load (Passive control);

[0099] Conditions for switching from operating condition 4 to operating condition 5: V dc2 <V dc2_2 (Passive control);

[0100] Among them, P wind P represents the power generation capacity of the wind turbine. load The load consumes power, and ΔV is the voltage margin for the hysteresis comparison.

[0101] Step 5: Based on the system operating conditions and control conditions, draw a state diagram covering all operating conditions, and generate control commands based on the state diagram to realize converter control across the entire wind speed range.

[0102] In this step, such as Figure 3 As shown (it should be noted that, to avoid making the state diagram overly complex, the state diagram shown here does not include the photovoltaic (PV) port case), the state diagram has a two-layer structure. The inner layer is the Level 1 operating condition dominated by the wind turbine's operating mode, and the outer layer is the Level 2 operating condition obtained by dividing the wind turbine's operating mode into power generation and non-power generation cases and combining other port cases. The PV port case is relatively simple. If the PV port case is included, when the PV generates power, its power can be considered as a factor of P. wind The superposition can be achieved simply by adding a higher-level working condition layer on the outer perimeter of the existing state diagram.

[0103] Furthermore, this embodiment provides a practical example of switching between Level 1 operating conditions (different modes of the wind turbine) of a multi-port converter.

[0104] Table 1 below shows the conditions for mode switching.

[0105] Table 1

[0106]

[0107] in:

[0108] Mode 0 is no-load operation, meaning the wind turbine is not powered (low wind speed no power generation mode), and both Q1 and Q2 switches are turned off.

[0109] Mode 1 is the medium wind speed power generation mode via the Boost circuit, that is, the wind turbine generates electricity via the Boost circuit, Q1 is turned off, and Q2 operates in MPPT mode;

[0110] Mode 2 is the high wind speed direct power generation mode, that is, the wind turbine generates power directly without going through the Boost circuit, and both Q1 and Q2 switches are turned off;

[0111] Mode 3 is the ultra-high wind speed short-circuit unloading mode, that is, the wind turbine is short-circuited and unloaded, Q1 is turned on in PWM mode, and Q2 is turned off.

[0112] Experimental conditions: A fan is added at the PMSG, V dc2 Add an electronic load and operate it in CV (Constant Voltage) mode. Change the duty cycle of the Boost switch and observe whether it can switch smoothly when the switching condition is met. The mode switching condition judgment period is 2 seconds.

[0113] like Figure 4 The waveform shown is the switching process of mode 0-1-2-3-2-1-0.

[0114] Time 1: V dc1 >100V, switch the working mode from 0 to mode 1;

[0115] Time 2: I Q2 >1.5A, switch the working mode from 1 to mode 2;

[0116] Time 3: I dc2 >0.8A, the duty cycle of the unloading switch drive signal gradually increases from 0;

[0117] Time 4: The duty cycle of the unloading switch drive signal accumulates to 100%, the unloading switch is normally open, and the working mode switches from mode 2 to mode 3;

[0118] Time 5: V dc1 / V dc2 If the value is less than 0.75, switch the operating mode from 3 to mode 2.

[0119] Time 6: V dc1 / V dc2 If the value is less than 0.55, switch the operating mode from mode 2 to mode 1.

[0120] Time 7: V dc1 < 80V, switch the operating mode from 1 to mode 0.

[0121] from Figure 4 As can be seen, the control method of the present invention can successfully drive the multi-port converter system to automatically and smoothly switch between four wind turbine operating modes under different conditions, verifying the feasibility and effectiveness of the control logic.

[0122] Through the above embodiments, the present invention can adapt to wind energy fluctuations across the entire wind speed range, effectively coordinate the energy flow between wind power generation, energy storage, and load, avoid overvoltage and overcurrent of converter devices, and improve the reliability and stability of system operation.

[0123] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. Those skilled in the art can readily make various modifications to the above embodiments and apply the general principles described herein to other embodiments without creative effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made to the present invention by those skilled in the art based on the disclosure thereof should be within the scope of protection of the present invention.

Claims

1. A control method for a new energy multi-port converter adaptable to all wind speeds, wherein the new energy multi-port converter includes a wind power generation port, a photovoltaic port, a battery port, and a load port, characterized in that, The control method includes the following sequential steps: Step 1: Determine the operating mode of the wind power generation port under different wind speeds, and measure the output voltage threshold of the rectifier circuit corresponding to each wind speed mode under no-load conditions; Step 2: Determine the three states of the battery in the battery port: charging, discharging, and low charge, and the two states of the load port: loaded and unloaded. Step 3: Determine the current threshold based on the maximum current stress that the switching transistor can withstand; Step 4: Based on the factors determined in Steps 1-3, different system operating conditions are identified, and the control conditions between each system operating condition are determined. Step 5: Based on the system operating conditions and control conditions, draw a state diagram covering all operating conditions, and generate control commands based on the state diagram to realize converter control across the entire wind speed range.

2. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 1, characterized in that, In step 1, the operating modes include: low wind speed no power generation mode, medium wind speed power generation mode via Boost circuit, high wind speed direct power generation mode, and ultra-high wind speed short-circuit unloading mode. The output voltage threshold of the rectifier circuit includes a first voltage threshold, a second voltage threshold, and a third voltage threshold, and satisfies the following: When the output voltage of the rectifier circuit is less than the first voltage threshold, the wind power generation port operates in the low wind speed no power generation mode. When the output voltage of the rectifier circuit is between the first voltage threshold and the second voltage threshold, the wind power generation port operates in the medium wind speed power generation mode via the Boost boost circuit. When the output voltage of the rectifier circuit is between the second voltage threshold and the third voltage threshold, the wind power generation port operates in the high wind speed direct power generation mode. When the output voltage of the rectifier circuit is greater than or equal to the third voltage threshold, the wind power generation port operates in the ultra-high wind speed short-circuit unloading mode.

3. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 1, characterized in that, The three states of the battery described in step 2 are characterized by the DC bus voltage: When the DC bus voltage is in the first bus voltage range, the battery port state of charge is between 0% and 5%, which is defined as a depleted state. When the DC bus voltage is in the second bus voltage range, the battery port state of charge is between 5% and 95%, which is defined as the normal charging and discharging range. When the DC bus voltage is in the third bus voltage range, the battery port state of charge is between 95% and 100%, which is defined as the fully charged state.

4. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 1, characterized in that, In step 3, the current threshold is used to determine the control conditions between the medium-wind-speed power generation mode via the Boost circuit and the high-wind-speed direct power generation mode. When the switching current of the medium wind speed power generation mode via the Boost circuit is greater than the sum of its maximum current stress and hysteresis margin, or when the ratio of the rectifier circuit output voltage to the DC bus voltage is greater than the preset upper limit of the ratio, the power generation mode via the Boost circuit for medium wind speed is controlled to the direct power generation mode for high wind speed. When the ratio of the rectifier circuit output voltage to the DC bus voltage is less than the preset lower limit, the system switches from high wind speed direct power generation mode to medium wind speed power generation mode via the Boost circuit.

5. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 1, characterized in that, In step 4, the specific system operating conditions are as follows: Operating condition 1: Wind turbine generates electricity, battery charges, load is applied; Operating Condition 2: Wind turbine generates electricity, battery discharges, load is applied; Operating condition 3: Wind turbine generating electricity, battery charging, load unloaded; Operating condition 4: The wind turbine is not generating electricity, the battery is discharging, and the load is under load; Operating Condition 5: The wind turbine is not generating electricity, the battery is depleted, and the load is unloaded.

6. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 5, characterized in that, The switching control conditions between the various system operating conditions mentioned in step 4 include: The passive control between operating condition 1 and operating condition 2 is based on the relationship between the power generated by the wind turbine and the power consumed by the load. The operation between operating condition 1 and operating condition 3 is actively controlled based on the load switching on and off actions. When the load is switched on, the wind turbine power generation must be greater than the load power consumption. The control between operating condition 1 and operating condition 4 is actively adjusted based on whether the DC bus voltage, DC bus current, or rectifier circuit output voltage exceeds a preset threshold. The control between operating conditions 2 and 3 is based on either active control during load shedding or passive control when the DC bus voltage is lower than the battery depletion threshold. Between operating conditions 3 and 2, active control is performed based on the load switching action, while passive control is performed when the wind turbine's power generation is not greater than the load's power consumption. The operation between Condition 4 and Condition 5 is passively controlled when the DC bus voltage is lower than the battery depletion threshold.

7. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 6, characterized in that, The specific switching conditions between operating condition 1 and operating condition 2 are as follows: When the wind turbine's power generation exceeds the load's power consumption, the system switches from operating condition 1 to operating condition 2; When the wind turbine's power generation is less than the load's power consumption, the system switches from operating condition 1 to operating condition 2.

8. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 6, characterized in that, The active control conditions for switching from operating condition 1 to operating condition 4 are as follows: the DC bus voltage at the battery port is greater than the sum of the full-charge voltage threshold and the voltage margin, or the DC current at the load port is greater than the maximum allowable current of the switching transistor, or the rectified voltage at the wind power generation port is less than the difference between the low wind speed start-up voltage threshold and the voltage margin. The active control conditions for switching from operating condition 4 to operating condition 1 are as follows: the ratio of the rectified voltage at the wind power generation port to the DC bus voltage at the battery port is greater than the sum of the switching constant and the voltage margin, and the DC bus voltage at the battery port is less than the difference between the maximum withstand voltage threshold and the voltage margin; or the rectified voltage at the wind power generation port is greater than the sum of the low wind speed start-up voltage threshold and the voltage margin.

9. The control method for a new energy multi-port converter adaptable to all wind speeds according to claim 6, characterized in that, The active control refers to the controller actively initiating switching actions or mode control commands; the passive control refers to the system's operating state transition caused by the natural satisfaction of external power or voltage conditions, with the controller only performing detection and following.

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