An industrial control system for wide voltage adaptation of a fan

Abstract

The present application relates to the technical field of industrial fan program control and wide voltage power supply regulation, in particular to an industrial control system for wide voltage self-adaption of a fan. The system synchronously collects input voltage, motor phase current, fan speed and pipeline pressure, identifies power supply disturbance according to state change sequence, determines inertia support interval, load release interval and gear shifting window in combination with speed attenuation, pipeline pressure and pneumatic regulating mechanism stroke, selects target gear from reachable connection combination of multi-gear voltage regulation loop; adjusts pneumatic load before gear shifting, executes interlock switching of first breaking and then closing in accordance with contact feedback in low current section, and completes operation verification and load recovery after switching according to current, phase sequence, speed and pressure. Thus, gear shifting time is matched with electromechanical and pneumatic state of the fan, invalid gear shifting caused by short-time disturbance is reduced, gear shifting current peak value, speed drop and pipeline pressure fluctuation are reduced, and load breaking of mechanical contact is reduced.

Description

Technical Field

[0001] This invention relates to the field of industrial fan program control and wide voltage power supply regulation technology, specifically an industrial control system for wide voltage adaptive operation of fans. Background Technology

[0002] In the power supply control of industrial ventilation, equipment cooling, and dust removal fans, the existing solution closest to the wide voltage adaptability requirement typically adopts an input voltage range detection and multi-range voltage regulation circuit switching structure. The input AC voltage is converted into an acquireable signal by a voltage transformer or isolation voltage divider circuit, and then rectified, filtered, and converted from analog to digital before being sent to the programmable controller. The programmable controller compares the acquired voltage with pre-defined undervoltage, normal, and overvoltage ranges, and combines hysteresis and duration conditions to generate range commands. The range execution part uses interlocking contactors and solid-state relays... Electrical appliances or thyristors can switch the taps of the autotransformer, which can also change the taps or series-parallel connection of the motor stator winding, so that the fan motor can obtain the terminal voltage corresponding to the input voltage range. During the start-up phase, the connection gear that can provide starting torque is called. During the operation phase, the gear shift is completed in the order of first disconnecting the original gear, confirming the status of the auxiliary contacts, and then connecting the target gear. At the same time, phase sequence, phase loss, current, thermal protection and speed switch signals are collected. In the event of overcurrent, stalled rotor or continuous undervoltage, the drive output is canceled, and the start-up sequence is re-executed after the voltage is restored and the protection status is released.

[0003] The aforementioned graded voltage regulation method uses whether the input voltage crosses the fixed interval boundary as the basis for grade switching. When the input voltage drops, repeatedly returns, or slowly deviates within a short period of time, the controller cannot determine whether the disturbance will continue based on the voltage change trajectory and the response sequence of phase current, fan speed, and pipeline pressure. It also cannot distinguish between similar current phenomena caused by power supply side changes and sudden changes in aerodynamic load. Under the same input voltage, the fan speed, pipeline resistance, and position of the aerodynamic regulating mechanism are different, resulting in different inertial time for the rotor to maintain rotation and different aerodynamic loads that can be released before grade switching. Fixed interval control does not establish a time range for grade switching based on this, and the contactor action delay is not synchronized with the low-value phase current segment. The resulting single technical problem is that there is a lack of dynamic matching relationship between the grade command and the current electromechanical and aerodynamic coupling state of the fan. The controller may initiate switching during short-term disturbances that do not require grade switching, or it may perform disconnection action before the load is released or the rotor support time is insufficient, leading to increased shifting current, decreased speed, pipeline pressure fluctuations, and contact arcing. Summary of the Invention

[0004] The purpose of this invention is to provide an industrial control system for wide voltage adaptive wind turbines, which can solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: An industrial control system for wide voltage adaptive wind turbine includes a data acquisition module connected to the wind turbine inlet circuit and the operating side, and a programmable controller connected to the data acquisition module. The programmable controller is also connected to a multi-stage voltage regulation circuit and a gear execution module of a pneumatic adjustment mechanism. The data acquisition module synchronously acquires electrical status data consisting of input voltage trajectory and motor phase current, as well as machine-air status data consisting of fan speed and pipeline pressure. The programmable controller generates a disturbance persistence state based on the temporal coupling of two types of state data, and maps the fan speed and pipeline pressure to a machine-air support state that constrains the disturbance persistence state. The target gear and shift window are determined by the machine-air support state. The gear shifting module adjusts the pneumatic regulating mechanism according to the shifting window and switches the multi-gear pressure regulating circuit in an interlocking sequence of first disconnecting and then closing.

[0006] Preferably, the data acquisition module is equipped with a common time base covering voltage sampling, phase current sampling and speed sampling, and writes the pipeline pressure sampling value and the position of the pneumatic regulating mechanism into the corresponding time base interval; The programmable controller establishes a disturbance event segment based on the starting point of the input voltage trajectory change, aligns the starting point of the phase current change, the starting point of the fan speed change, and the starting point of the pipeline pressure change to the disturbance event segment in sequence, and generates a power supply disturbance identifier or a pneumatic load disturbance identifier based on the order and direction of each change starting point. The disturbance duration is generated by the continuous event segment corresponding to the power supply disturbance identifier.

[0007] Preferably, the programmable controller extracts the continuous change sequence of the fan speed from the disturbance event segment, and combines it with the current pipeline pressure and the movable stroke of the pneumatic regulating mechanism to generate the rotor inertia support range and the load release range. The time range corresponding to the rotor inertia support range, the load release range and the disturbance duration state are overlapped to form a shift window that allows the gear to be disconnected and connected. Select the target gear corresponding to the current input voltage direction and pipeline pressure status from the reachable connection combinations of the multi-level voltage regulation circuit, and associate the target gear with the gear shift window.

[0008] Preferably, the programmable controller is configured with a shift state sequence that switches between holding, load release, disconnection confirmation, target gear activation, operation verification, and load recovery in that order; After entering the load release state, the gear execution module moves the pneumatic adjustment mechanism to the position corresponding to the load release state, and cancels the original gear drive after the phase current enters the shift window; After the auxiliary contact of the original gear returns to the off state, the gear execution module connects to the target gear and completes the transition between the operation verification state and the load recovery state based on the switched phase current, fan speed and pipeline pressure.

[0009] Preferably, the programmable controller intercepts a reference data segment without gear operation instructions before each disturbance event segment, and establishes a change difference sequence between the reference data segment and the input voltage, phase current, fan speed and pipeline pressure in the disturbance event segment. Using input voltage, phase current, fan speed, and pipeline pressure as event nodes, and the transmission order and direction of change of the starting point of change as the node connection relationship, a disturbance propagation chain is formed. A disturbance source tag is generated based on the first event node and the order of subsequent nodes in the disturbance propagation chain, and the electrical transient segment formed by the contactor action is removed from the disturbance propagation chain using the time stamp of the gear operation command.

[0010] Preferably, the programmable controller establishes a power supply event queue representing the continuous deviation of the input voltage and a mechanical event queue representing the continuous decay of the fan speed, respectively. When the input voltage briefly returns while the phase current and fan speed have not yet recovered to the corresponding reference data segment, the adjacent power supply events are kept continuous within the same disturbance event segment. When the pipeline pressure changes before the phase current changes, the corresponding segment will be transferred to the pneumatic load disturbance flag. The disturbance persistence state is generated by the overlapping range of the power supply event queue and the mechanical event queue, and is written into the shift window record together with the load release interval.

[0011] Preferably, the data acquisition module also acquires the air volume and the actual position of the pneumatic adjustment mechanism, and the programmable controller establishes a gear load relationship table indexed by the current gear, disturbance source label, and pneumatic load status; Each entry is associated with the reachable connection combination of multiple voltage regulation circuits, the fan speed before shifting, the phase current sequence after shifting, the speed recovery sequence, and the movable stroke of the pneumatic adjustment mechanism. The target tier is selected from the reachable join combination that matches the current index and has a complete running verification record. If no matching table entry is found, a candidate tier sequence is constructed according to the adjacent reachable join combination.

[0012] Preferably, the gear position execution module includes a phase current zero-crossing detection interface, a contactor auxiliary contact acquisition interface, and an interlock drive circuit; The programmable controller generates a drive advance based on the adjacent zero-crossing times of the phase current and the historical action delay of the original gear contactor, so that the separation time of the original gear main contact falls into the low current section of the shift window. The interlock drive circuit blocks the target gear drive when the original gear auxiliary contact has not returned to the open state, and collects the continuity of current and phase sequence status of each phase after the target gear is turned on, and writes the collection results into the operation verification status.

[0013] Preferably, the programmable controller extracts relation table update samples only from disturbance event segments with power supply disturbance source tags, complete shift state sequences and continuous sampling time bases, and combines the input voltage trajectory before shift, current gear, pipeline pressure and fan speed into a pre-state record, and combines the target gear, phase current sequence after shift, speed recovery sequence and the actual position of the pneumatic adjustment mechanism into a post-state record. Write the subsequent state records into the gear load relationship table according to the adjacency relationship of the preceding state records, and store the event segments containing pneumatic load disturbance source tags, sensor interruption tags, or interlock abnormality tags into the isolation record area.

[0014] Preferably, when the programmable controller enters the load release state, it saves the original gear position, the original position of the pneumatic adjustment mechanism, the fan speed before the gear shift, and the input voltage trajectory, forming a transaction snapshot bound to the gear shift state sequence. After the target gear is turned on, the phase current continuity, phase sequence status and speed change sequence are written into the same transaction record; When the operation verification state fails to obtain continuous phase current or the fan speed continues to decline, the gear execution module maintains the load release position of the pneumatic adjustment mechanism and calls the reverse interlock sequence from the target gear to the original gear, and sequentially disconnects the target gear and connects the original gear in the subsequent low current section. When the original gear auxiliary contact is abnormal, the gear shift state sequence enters the isolation shutdown state.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By using a common time base to collect input voltage trajectories, motor phase currents, fan speeds, and pipeline pressures, disturbance event segments are established based on the voltage change starting point. Power supply disturbance and aerodynamic load disturbance identifiers are generated according to the transmission order of the starting points of each state variable change. This allows short-term voltage return, continuous power supply offset, and load-priority changes to be included in their respective event sequences. Within the power supply disturbance event, the rotor inertia-supportable range is determined using the continuous speed change sequence, and the load-releaseable range is formed by combining pipeline pressure and the movable stroke of the aerodynamic adjustment mechanism. The two types of intervals are overlapped with the duration of the disturbance to generate a shift window; before the shift window arrives, the shift execution module adjusts the pneumatic regulating mechanism, and after the phase current enters the low value section, it sequentially disconnects the original shift and connects the target shift, and enters the operation verification and load recovery sequence according to the phase current, speed and pipeline pressure after the switch, so that the shift time corresponds to the actual shiftable state of the fan, reduces the number of invalid shifts caused by short-term disturbances, and reduces the peak phase current, speed drop, pressure fluctuation range and mechanical contact load disconnection degree during the shift period.

[0016] 2. The disturbance propagation chain associates the changes in input voltage, phase current, fan speed, and pipeline pressure with the gear operation time stamp, which can separate the electrical transient segments formed by contactor action from the sampled data, reducing the interference of the gear operation waveform itself on the judgment of the disturbance source; the gear load relationship table records the current and speed sequences of the available connection combination and after gear shift according to the current gear, disturbance source, and pneumatic load status, and stores the events corresponding to sensor interruption, abrupt change in pneumatic load, and interlock anomaly in the isolation record area, so that the subsequent target gear selection uses data with complete source and verified operation; the phase current zero-crossing detection interface, auxiliary contact acquisition interface, and interlock drive circuit jointly correct the contactor drive timing, and keep the target gear locked when the original contact has not been confirmed to be open; the gear shift transaction snapshot saves the original gear, pneumatic adjustment mechanism position, and operating status before gear shift, and calls the reverse interlock sequence when the operation verification does not form a continuous phase current or the speed continues to decay, thereby reducing short circuits between adjacent gears, accumulation of error samples, and repeated gear shifts under abnormal conditions, and shortening the processing time required for the control sequence to return to a verifiable state. Attached Figure Description

[0017] Figure 1 A flowchart is generated for disturbance identification and gear shifting window; Figure 2 To unify the time base attribution diagram; Figure 3 For contactor delay health graph; Figure 4 This is a consistency graph for event packet replay. Detailed Implementation

[0018] In one embodiment, an industrial control system for wide-voltage adaptive operation of a fan includes a data acquisition module connected to the fan's inlet circuit and operating side, and a programmable controller connected to the data acquisition module. The programmable controller is also connected to a gear execution module for a multi-level voltage regulation circuit and a pneumatic adjustment mechanism. The data acquisition module synchronously acquires electrical state data consisting of the input voltage trajectory and motor phase current, as well as machine-air state data consisting of fan speed and pipeline pressure. The programmable controller generates a disturbance persistence state based on the temporal coupling of the two types of state data, and maps the fan speed and pipeline pressure to a machine-air support state that constrains the disturbance persistence state. The machine-air support state determines the target gear and the gear shifting window. The gear execution module adjusts the pneumatic adjustment mechanism according to the gear shifting window and switches the multi-level voltage regulation circuit in an interlocking sequence of first disconnect and then reconnect.

[0019] In this embodiment, the fan is arranged in an industrial ventilation duct, equipment cooling duct, or dust removal conveying duct. A multi-stage voltage regulation circuit is connected in series between the AC incoming line and the fan motor. The pneumatic adjustment mechanism adopts any one of the following: an electric damper, an inlet guide vane, or a bypass actuator that can change the inlet flow area. The data acquisition module is connected to the incoming line voltage detection branch, the motor phase current detection branch, the shaft speed detection branch, and the pipeline pressure detection branch, and adds a time stamp to each data through the same acquisition clock. The programmable controller internally stores the current gear, the allowed connection relationship of each gear, the current position of the pneumatic adjustment mechanism, and the control state being executed. The gear execution module receives control commands with status numbers and transaction markers. The auxiliary feedback of the mechanical contacts, the position feedback of the pneumatic adjustment mechanism, and the sampled data are returned to the programmable controller along the feedback channel, so that a gear change, from disturbance identification, machine and air status confirmation, execution control to operation verification, is all associated with the same disturbance event record.

[0020] Specifically, the input voltage detection branch obtains the low-energy sampling signal corresponding to the AC input line through an isolation converter, and the motor phase current detection branch obtains the current sampling signal of each phase through a current transformer. The two types of signals are written into a circular buffer after anti-aliasing filtering and analog-to-digital conversion. The programmable controller retains the uncompressed cycle sampling sequence and extracts the voltage envelope, zero-crossing time, voltage change direction, current envelope, and phase current continuity from the continuous cycles. Peak samples are marked as isolated disturbances only when there is no change in the same direction between adjacent samples and are not used to change the event state. During the installation phase, the voltage and current channels establish a conversion table through the same reference source. During operation, the sampling code is mapped to the engineering quantity according to the conversion table. The version identifier of the conversion table is stored together with the sampling record to ensure that cross-time events can be compared under the same dimension, while retaining the original sampling code for use in transient verification during gear shifting.

[0021] Preferably, the fan speed is calculated from the shaft-end encoder, magnetic speed sensor, or motor commutation signal; the pipeline pressure is obtained from the pressure acquisition branches set at the fan inlet and outlet; and the position of the pneumatic adjustment mechanism is given by the actuator feedback contact or position sensor. The speed sampling record includes pulse count and adjacent pulse interval per unit time. In the low-speed zone, the pulse interval is used to maintain the resolution of the speed sequence, while in the stable operation zone, continuous counting is used to suppress single pulse jitter. The pipeline pressure sampling forms a pressure change sequence after zero-point correction. When sampling points are set at both the inlet and outlet, a differential pressure sequence is also generated. The position feedback is converted into a record of the remaining stroke from the current mechanical position to the end of the unloading direction stroke, and is bound to the actuator's start time, position change time, and stroke completion time. The record serves as the data basis for judging whether the pneumatic load can be released during the rotor inertia maintenance period.

[0022] Furthermore, the data acquisition module uses the zero-crossing mark of the incoming line voltage as the periodic boundary of the electrical channel and the monotonic clock of the programmable controller as the unified time reference across channels. Speed ​​pulses, pressure sampling, and position feedback are all written into adjacent electrical period intervals according to their arrival times. When the field acquisition branch is connected through the isolated communication interface, the acquisition end writes the local time mark and frame sequence number into the data frame. The programmable controller corrects the local time mark according to the arrival interval of consecutive frames and places frames that cannot be corrected into the sensor interrupt record without participating in the shift judgment. The circular buffer is divided into a reference data area, a disturbance data area, and a shift data area. The reference data area stores the state segment of the most recent operation without control action and with stable operation. The disturbance data area retains the reference segment forward from the voltage change point and extends backward. The shift data area continuously records from the time the load release command is issued until the end of the operation verification, so that the generation of various states can be traced back to the corresponding original sequence.

[0023] In this embodiment, please refer to Figure 1 The programmable controller uses the synchronous changes of the input voltage trajectory and the phase current trajectory as power supply side observations, and the synchronous changes of the fan speed and pipeline pressure as machine-air side observations. It establishes a temporal correlation between the two types of observations based on the order of change. When the voltage changes continuously first, the phase current changes subsequently, and the speed shifts in the same direction, the disturbance event is written into the power supply event queue. When the pipeline pressure changes first and the voltage remains within the fluctuation range of the reference data area, the event is written into the pneumatic load queue. When the power supply event queue is still in a continuous state, the programmable controller forms a rotor inertia-supportable range based on the speed decay trajectory, and forms a load-releaseable range based on the pressure change and the remaining stroke of the pneumatic adjustment mechanism. Only when the two ranges have a common time period will a shift window be generated that can be called by the gear execution module. If they cannot form a common time period, the original gear is maintained and pneumatic unloading continues or the controlled shutdown state is entered.

[0024] Specifically, the multi-gear voltage regulation circuit consists of autotransformer taps, segmented winding connection branches, or voltage regulation contacts with equivalent gear relationships. The programmable controller registers each legal connection state as a gear node and registers the connection states that allow direct switching from the current gear as reachable edges. The target gear is generated from the gear node corresponding to the reachable edge based on the direction of input voltage change. The selected gear must also meet the pneumatic support conditions corresponding to the pipeline pressure state, current speed, and the movable stroke of the pneumatic adjustment mechanism. After the gear shift window is generated, the gear execution module first outputs a pneumatic unloading command. After the position feedback enters the expected movement direction and the phase current decreases accordingly, it issues a disconnect command for the original gear. The target gear is only allowed to be connected after the auxiliary contact of the original gear confirms that it is disconnected. The continuity of phase current, the direction of speed change, and the pipeline pressure recovery state after the target gear is engaged are written into the operation verification record. The gear shift transaction mark is not revoked before the operation verification record is closed.

[0025] In a preferred embodiment, the data acquisition module is equipped with a common time base covering voltage sampling, phase current sampling, and speed sampling, and writes the pipeline pressure sampling value and the position of the pneumatic regulating mechanism into the corresponding time base interval; the programmable controller establishes a disturbance event segment based on the starting point of the input voltage trajectory change, aligns the starting point of the phase current change, the starting point of the fan speed change, and the starting point of the pipeline pressure change to the disturbance event segment in sequence, and generates a power supply disturbance identifier or a pneumatic load disturbance identifier according to the order and direction of each change starting point, and the disturbance duration is generated by the continuous event segment corresponding to the power supply disturbance identifier.

[0026] In this embodiment, the shared time base is not a simple time splicing of different sampling channels, but is composed of electrical cycle boundaries and a monotonic clock. Voltage and phase current sampling maintain a fixed sequence position within each electrical cycle, while speed, pressure, and position data are inserted into the corresponding cycle according to time markers. When the programmable controller performs time alignment for each channel, it does not change the original sampled values, but only generates an alignment index pointing to the original data position. The alignment index includes a pre-event reference area, a transition area, and a post-event state area. When the arrival time of data from a certain channel crosses the cycle boundary, the belonging interval is determined based on the sequence number of the preceding and following frames and the continuity of the monotonic clock. Data that cannot be determined to belong to is marked as suspended data. The starting point of the disturbance event segment is the first time marker where the voltage envelope continuously deviates from the reference interval, and the ending position is determined by the compatible state where voltage, current, and speed jointly recover to the reference data area, avoiding premature truncation of the event due to a brief voltage return.

[0027] Please refer to Figure 2 , Figure 2The horizontal axis represents the continuous sampling and assignment process from the reference area, transition area, window locking area, execution area to the recovery observation area, divided into the beginning, middle, end, and end segments. The vertical axis represents the alignment deviation and the stable assignment value. The solid line represents the time base deviation, the long dashed line represents the frame span fluctuation, the dotted line represents the assignment stability, and the horizontal reference line is used to mark the reference boundary of stable assignment. The three types of curves correspond to the alignment relationship between the electrical cycle boundary, the monotonic clock, and the sampling frame number in the text.

[0028] from Figure 2 As can be seen, the time base deviation curve fluctuates around the baseline range in most stages, with extreme values ​​between -2.16 and 2.16, indicating that there is an observable but controlled time correction when channel data enters the unified index across cycles. The frame span fluctuation curve has an amplitude of approximately -1.08 to 1.08, and the direction of change does not completely coincide with the time base deviation, indicating that frame sequence continuity and local time correction are two different criteria for determining the attribution of a sampling point, and a single timestamp cannot be used to determine the attribution of a sampling point.

[0029] The attribution stability curve is generally above the reference line, reaching a maximum of approximately 2.71, and remaining around 1.8 at the end, indicating that most sampled records can be assigned to a clear pre-event reference region, transitional region, or recovery observation region. If the curve dips locally and is accompanied by a widening of the frame span, it corresponds to suspended data or uncertain data at cross-period boundaries as described in the text, and subsequent disturbance start and end positions and shift window versions should not immediately use this segment.

[0030] Specifically, the voltage envelope, phase current envelope, speed, and pressure within the reference data area form a reference sequence. The programmable controller calculates the direction of change of adjacent values ​​according to the sampling order, and uses whether continuous unidirectional changes cross the sensing noise band as the confirmation condition for the starting point of the change. The sensing noise band is generated by the fluctuation distribution of the same channel within the reference data area and is recalculated as the sensor drifts, but the corresponding noise band is frozen when performing disturbance identification or shifting transactions. Each starting point of change records the channel type, time stamp, direction of change, number of continuous samples, and relative reference state. Then, the starting points of phase current, speed, and pressure changes are mapped to the event segment where the voltage change starting point is located. If a channel only has an isolated jump and subsequent sampling returns to the reference distribution, the original data is retained and the starting point mark of the channel is removed, so that the event segment will not form a power supply disturbance mark due to single-point noise.

[0031] Furthermore, power supply disturbance indicators are established according to the propagation order of voltage change leading, phase current response following, and speed response lagging. Pneumatic load disturbance indicators are established according to the propagation order of pressure change leading, phase current response following, and input voltage maintaining the reference distribution. When voltage and pressure changes occur in adjacent time intervals and cannot be separated according to their order, the event segment is set to a composite pending state. The programmable controller maintains its original setting and continues to collect data until subsequent phase current and speed changes form a discernible propagation direction. After the power supply disturbance indicator is confirmed, even if there is a short-term voltage return between adjacent event segments, as long as the phase current and speed do not form a recovery chain, they are still connected as the same disturbance process through continuous event marking. After the pneumatic load disturbance indicator is confirmed, the controller only allows the execution of the pneumatic regulation state and does not call the target setting of the multi-level voltage regulation loop, thus isolating the control branches corresponding to power supply changes and load changes at the data source level.

[0032] In a preferred embodiment, the disturbance event segment employs a traceable boundary structure. A reference segment covering the stable operating state of the motor is retained before the starting point, and an observation segment confirming the recovery trend is retained after the ending position. When subsequent data indicates that the original starting point was caused by contactor operation or sensor jitter, the controller moves the starting point backward along the alignment index and regenerates the propagation order. When subsequent data indicates that the recovery is only a brief return, the ending position is extended along the alignment index without copying the original sample. Each boundary adjustment generates a version record, with the power supply disturbance identifier, pneumatic load disturbance identifier, and composite pending identifier referencing the corresponding version. Gear selection only uses the currently effective version. Event segments that have entered the gear shifting state sequence stop modifying the starting point and are only allowed to extend the ending position, ensuring that the data boundary referenced by the execution command remains consistent during gear shifting.

[0033] In a preferred embodiment, the programmable controller extracts the continuous change sequence of the fan speed from the disturbance event segment, and generates the rotor inertia support range and the load release range by combining the current pipeline pressure and the movable stroke of the pneumatic regulating mechanism; the rotor inertia support range, the load release range and the time range corresponding to the disturbance duration state are overlapped to form a shift window that allows the execution gear to be disconnected and connected; the target gear corresponding to the current input voltage direction and pipeline pressure state is selected from the reachable connection combination of the multi-gear voltage regulation circuit, and the target gear is associated with the shift window.

[0034] Specifically, the rotor inertia-supportable range is generated by a continuous sequence of rotational speeds after the disturbance begins. The programmable controller first eliminates abrupt changes corresponding to isolated encoder pulses, and then calculates the attenuation direction and duration of adjacent speed segments in chronological order. Taking the stable speed in the most recent reference data area as the starting state, and the minimum operating state where the fan can maintain continuous ventilation and the motor can rebuild electromagnetic torque as the termination boundary, the remaining support period is obtained by extrapolating to the termination boundary based on the current attenuation sequence. During the extrapolation process, the attenuation trend is corrected by changes in phase current and pipeline pressure. When the pressure continues to rise and the phase current does not fall back, the support period is shortened. When the pneumatic adjustment mechanism has moved in the unloading direction and the pressure begins to fall back, the updated attenuation segment is used for recalculation, thus forming a time interval record that changes with the field conditions.

[0035] Preferably, the load release interval is formed based on the current position of the pneumatic regulating mechanism, the remaining movable stroke, and the historical action trajectory. The controller reads the execution delay from the issuance of the command to the start of position change, the time period required for continuous position change, and the order in which pressure and phase current begin to respond from the most recently completed unloading record without interlocking abnormalities. After the current actuator issues an unloading command, the actual position feedback replaces the historical trajectory to enter the interval update. When the position feedback stops, the load release progress is frozen. When the pressure does not change with the position change, the pipeline status is set to pending confirmation. Only when the position movement direction, pressure change direction, and phase current change direction are compatible with the unloading record is the estimated time from the current moment to the completion of the load release state written into the load release interval. When the actuator has no position sensor, the stroke state is determined by the drive output feedback and the pressure change start point, and the uncertain interval is retained in the operation verification record.

[0036] Furthermore, the shift window is formed by subtracting the time period during which the pneumatic unloading has not yet been completed from the rotor's inertial support range, and is constrained by the effective range of the disturbance persistence state. The programmable controller superimposes the low-value segment of phase current and the physical contact change segment corresponding to the contactor action delay within the candidate time period. Only when the unloading state has been confirmed, the rotor is still within the support range, and the original gear can complete the disconnection in the low-current segment, will the candidate time period become an executable window. When multiple executable windows appear consecutively, the controller selects the window that can accommodate the complete disconnection confirmation and the target gear connection process. The window is bound to this shift transaction after execution begins and will not be replaced by subsequent candidate windows. If the change in pneumatic unloading speed causes the window to shrink, the controller decides whether to return to the load release state or continue to complete the interlock sequence that has already started, depending on whether the contacts have already acted.

[0037] In this embodiment, the gear nodes of the multi-gear voltage regulation circuit record the input-side connection relationship, output-side connection relationship, phase sequence constraints, and the allowed switching direction with adjacent gears. When selecting the target gear, the connection combination that would cause the motor terminal voltage to continue to deviate is first eliminated based on the direction of input voltage rise or fall. Then, the connection combination that cannot maintain the current pneumatic load after gear shift is eliminated based on the current pipeline pressure, fan speed, and load release range. The remaining gears are arranged according to the number of connection changes with the current gear, the integrity of historical operation verification, and the reachability status of the contacts. The controller selects the gear nodes that are ranked first and can complete the interlocking conversion within the existing gear shift window. Once the target gear is associated with the gear shift window, the gear execution module only accepts disconnect and connect commands with the same transaction flag. When the target gear becomes unreachable due to auxiliary contact abnormality, the controller cancels the association and reselects from the remaining gears.

[0038] In a preferred embodiment, the programmable controller is configured with a shift state sequence that switches between holding, load release, disconnection confirmation, target gear activation, operation verification, and load recovery. After entering the load release state, the gear execution module moves the pneumatic adjustment mechanism to the position corresponding to the load release state and cancels the original gear drive after the phase current enters the shift window. After the auxiliary contact of the original gear returns to the disconnected state, the gear execution module activates the target gear and completes the transition between the operation verification state and the load recovery state based on the switched phase current, fan speed, and pipeline pressure.

[0039] Specifically, the system continuously receives feedback on the version of the disturbance event segment and the current gear position. After the power supply disturbance flag takes effect and the gear shift window has been generated, the state sequence carries the event flag and transitions to the load release state. In the load release state, the pneumatic regulating mechanism is only allowed to move in the direction of reducing pneumatic torque, and the position feedback, pipeline pressure, and phase current are continuously checked to see if they form a compatible change. After the executable window arrives, the controller locks the target gear position and transaction flag and transitions to the disconnection confirmation state. After the original gear position drive is canceled, the software status bit, drive circuit feedback, and auxiliary contact feedback are checked simultaneously. The target gear position is only entered when all three types of feedback indicate that the original gear position is disconnected. If any feedback still indicates that the original gear position is closed, the target gear position drive remains blocked, the state sequence remains in the disconnection confirmation state, and the contact feedback trajectory is recorded.

[0040] Furthermore, when the target gear is engaged, a drive command with a transaction marker is issued and the target auxiliary contact is monitored. After the phase current is re-established, the operation verification state is entered. In the operation verification state, the continuity of the phase current, phase sequence, direction of speed change, and direction of pipeline pressure change after the gear shift are compared with the verification record corresponding to the target gear. If the current is not continuously established, the phase sequence is inconsistent, or the speed continues to decay, the load recovery state is not entered. After the verification conditions are closed, the pneumatic regulating mechanism returns to the load position before the gear shift in segments according to the position feedback. After each position change interval is completed, the phase current, speed, and pressure are reread. When the three types of operating quantities remain compatible, the recovery continues. When any operating quantity turns into an abnormal trend, the current position is frozen and the operation verification state is returned. The gear shift transaction is closed after the pneumatic regulating mechanism returns to the target load position and the event segment enters the recovery state.

[0041] In a preferred embodiment, the state sequence is stored in pairs using non-volatile state records and running memory state records. The non-volatile records contain transaction flags, original gear positions, target gear positions, most recently completed states, and auxiliary contact combinations. The running memory stores high-frequency sampling and intermediate judgment data. Before each state transition, a transition flag is written first, and then an execution command is output. After receiving the corresponding feedback, the transition flag is changed to a completed flag. When the controller restarts after an interruption, the output register is not directly reused. Instead, the non-volatile records are read and the auxiliary contacts, input voltage, and phase current are re-acquired. The controller is restored to the hold, disconnection confirmation, or isolation shutdown state based on the actual contact combination. When the recorded state is inconsistent with the actual contact combination, all gear position drives are canceled, and only the acquisition and pneumatic unloading commands are allowed to be executed until the contact combination is confirmed.

[0042] In a preferred embodiment, the programmable controller intercepts a reference data segment without gear operation instructions before each disturbance event segment, and establishes a change difference sequence between the reference data segment and the input voltage, phase current, fan speed, and pipeline pressure in the disturbance event segment. Using the input voltage, phase current, fan speed, and pipeline pressure as event nodes, and the transmission order of the change starting point and the change direction as the node connection relationship, a disturbance propagation chain is formed. A disturbance source label is generated according to the first event node and the order of subsequent nodes in the disturbance propagation chain, and the electrical transient segment formed by the contactor action is removed from the disturbance propagation chain using the time stamp of the gear operation instruction.

[0043] In this embodiment, the reference data segment is obtained by tracing back from the starting point of the current disturbance event segment. The tracing process excludes time intervals containing gear drive commands, pneumatic adjustment commands, sensor interruption markers, and protection state transitions, and requires that the input voltage, phase current, speed, and pressure remain corresponding to each other in continuous sampling. The reference sequence of each channel is paired with the disturbance sequence according to the same time index. The variation difference sequence records the direction, duration, and cumulative deviation of the current sample relative to the corresponding position of the reference sequence. Periodic signals are paired according to the same electrical phase, and low-speed pulse signals are paired according to the interval between adjacent pulses. When the reference data segment is insufficient to cover the stable state, no new disturbance source label is generated. Instead, the pending label is used and sampling continues until a comparable reference segment is formed.

[0044] Specifically, the disturbance propagation chain is stored using a directed event graph. The starting points of changes in input voltage, phase current, fan speed, and pipeline pressure constitute event nodes. Each node records a time stamp, direction of change, duration interval, and the location of the original data referenced. When the change time of the preceding node is earlier than that of the following node, and the directional relationship between the two nodes conforms to the order of the fan's electrical and aerodynamic responses, a directed connection is established between the nodes. The connection records the time interval and propagation type. A propagation chain starting with the input voltage node and sequentially connecting the phase current node and the speed node is written into the power supply disturbance source label. A propagation chain starting with the pipeline pressure node and connecting the phase current node and the speed node, but lacking a leading voltage node, is written into the aerodynamic load disturbance source label. Nodes that cannot form a complete connection are retained in the undetermined node set and re-evaluated as the event boundary expands.

[0045] Furthermore, each gear shifting command and auxiliary contact change generates an operation time stamp, which is associated with the command issuance time, the expected contact action interval, and the actual auxiliary contact change time. After the disturbance propagation chain is generated, the programmable controller retrieves the operation time stamps that overlap with the event node time interval and marks the voltage and current nodes that occur during the original gear disengagement, target gear engagement, and contact bounce as control-endogenous nodes. Control-endogenous nodes are removed from the disturbance source determination chain, but their original samples are still stored in the gear shifting data area and used for contactor action delay updates. When the propagation chain is incomplete after removing a node, the original disturbance source label is downgraded to a pending label. When a node that is continuous with the original power supply change appears later, the power supply disturbance source label is restored to prevent the transient generated by the gear shift itself from being repeatedly identified as a new power supply event.

[0046] In a preferred embodiment, the programmable controller establishes a power supply event queue representing the continuous deviation of the input voltage and a mechanical event queue representing the continuous decay of the fan speed. When the input voltage briefly returns but the phase current and fan speed have not yet recovered to the corresponding reference data segment, adjacent power supply events are kept continuous within the same disturbance event segment. When the pipeline pressure changes before the phase current changes, the corresponding segment is transferred to the pneumatic load disturbance flag. The disturbance persistence state is generated by the continuous range of the power supply event queue and the overlapping range of the mechanical event queue, and is written into the shift window record together with the load release interval.

[0047] Specifically, each queue entry in the power supply event queue stores the start time, direction of change, return segment, corresponding phase current response, and current source tag of the input voltage deviation. Each queue entry in the mechanical event queue stores the start time, direction of speed decay, pipeline pressure status, and position of the pneumatic regulating mechanism. When a new sample arrives, if the input voltage still deviates in the original direction, the current power supply queue entry is extended. If the input voltage returns but the phase current and speed have not yet formed a recovery sequence, the return data is written to the current queue entry without ending the event. Only when the input voltage, phase current, and speed return to the reference state in the reverse order of the power supply disturbance propagation does the current power supply queue entry enter the closed state. The mechanical event queue closes after the speed stops decaying and forms a continuous recovery segment, avoiding the use of a single speed fluctuation to determine the end of the inertial support.

[0048] Preferably, when the pipeline pressure change starts earlier than the phase current change and the input voltage node remains in the reference state, the controller will cancel the corresponding power supply queue candidate and connect the phase current and speed nodes to the pneumatic load disturbance flag. When pressure and voltage change simultaneously, the two queues remain in a pending state in parallel until the phase current response direction, speed decay direction, and subsequent pressure trend form a complete propagation chain. The overlapping part of the power supply event queue and the mechanical event queue on the time axis generates a disturbance persistence record. The start point of the overlapping part must not be earlier than the power supply change start point, and the end point must not be later than the end point of the rotor inertia-supportable interval. After the load release interval is written into the same record, the programmable controller can directly retrieve the executable interval between the unloading completion position and the remaining support period without re-splitting data from different sources during the gear execution stage.

[0049] In a preferred embodiment, the event queue uses non-overwrite sequence numbers to connect adjacent segments. Each return, deviation, or source tag change generates a sub-segment and retains the parent queue item identifier. When a sensor recovers from an interruption, the recovered data establishes a new sub-segment, directly extending the original segment without crossing the interruption interval. The controller determines whether to allow two sub-segments to be included in the same disturbance process based on the voltage direction and contact status before and after the interruption. The shift window records the referenced specific sub-segment range, the load release interval version, and the target shift version. When any referenced object is revoked, shift windows that have not yet started execution synchronously fail. Transactions that have entered the disconnection confirmation state maintain their original interlock sequence and are transferred to the running verification state for processing.

[0050] In a preferred embodiment, the data acquisition module also acquires the air volume and the actual position of the pneumatic adjustment mechanism. The programmable controller establishes a gear load relationship table indexed by the current gear, disturbance source label, and pneumatic load status. Each entry is associated with the reachable connection combination of multiple gear pressure regulating circuits, the fan speed before gear shift, the phase current sequence after gear shift, the speed recovery sequence, and the movable stroke of the pneumatic adjustment mechanism. The target gear is selected from the reachable connection combination that matches the current index and has a complete operation verification record. If no matching entry is obtained, a candidate gear sequence is constructed according to the adjacent reachable connection combination.

[0051] In this embodiment, the air volume sampling value and the pipeline pressure sampling value together form the pneumatic load state. The controller divides the pneumatic load state into stable delivery, resistance increase, unloading transition and load recovery records according to the direction of air volume change, the direction of pressure change and the position of the pneumatic adjustment mechanism. The gear load relationship table adopts a hierarchical index structure. The upper index is the current gear and disturbance source label, and the lower index is the pneumatic load state and the direction of input voltage change. The table entries store the data version, source event, reachable connection combination and operation verification result. Multiple verified gear change records can be stored under the same index. The original phase current sequence and speed sequence are stored in association through event identifiers. The table entries only store references that can locate the original sequence and representative change trajectories to avoid the compression result deviating from the original sampling.

[0052] Specifically, the reachable connection combination is generated based on the actual wiring of the multi-speed voltage regulation circuit. The controller reads the input terminal, output terminal, interlock object and auxiliary contact status of each contactor to construct the speed node and the allowed switching edge. After maintenance or wiring changes, the no-load contact combination is read one by one in the debugging state and checked against the wiring configuration. Only the nodes that have been checked are written into the reachable connection set. If the auxiliary contact status of a contactor is inconsistent with the drive status during operation, the corresponding node and the switching edge connected to it are set to unreachable. The relationship table retains the historical record but no longer provides the node to the target speed selection. Node recovery requires the contact status verification to be completed in the non-speed-changing state and a new reachable connection version to be generated. The transaction being executed continues to reference the old version locked at startup.

[0053] Furthermore, each shift record includes the input voltage trajectory before the shift, fan speed, air volume, pipeline pressure, and pneumatic adjustment mechanism position, as well as the phase current establishment process, speed recovery process, pressure recovery process, and final load position after the shift. The controller uses a common time base to time-align the shift records, using the original shift disconnection time and the target shift connection time as two positioning points, so that records of different durations can be compared according to the same control event. Records that verify the closure are entered into the available record set, while records that experience sensor interruption, interlocking abnormality, composite pending disturbance, or controlled shutdown are entered into the isolation set. Adjacent trajectories in the available record set generate representative trajectories for entries according to the direction of change and the order of duration. When a new record is compatible with a representative trajectory, the entry reference is updated; when incompatible, it is retained as a candidate branch and awaits verification by subsequent similar events.

[0054] In this embodiment, the target gear selection first uses the current gear, power supply disturbance source tag, and pneumatic load status to search for a fully matching entry. If a fully matching entry exists, combinations with abnormal auxiliary contacts, failed switching edges, or those that cannot be accommodated in the current gear shift window are removed from the reachable connection combinations associated with the entry. Then, the phase current continuity, speed recovery direction, and movable stroke of the pneumatic adjustment mechanism in the remaining records are compared. If no fully matching entry exists, the controller searches for neighboring entries according to the pneumatic load status adjacency relationship and sequentially writes the gear nodes that only change one reachable connection edge into the candidate gear sequence. After the candidate gear is put into operation, the pneumatic adjustment mechanism is kept in the unloaded position. The next gear in the sequence is allowed to be called only after the operation verification is completed. If the current is discontinuous or the speed continues to decrease in any candidate gear, the candidate sequence is stopped and the system enters the rollback state.

[0055] In a preferred embodiment, the gear position execution module includes a phase current zero-crossing detection interface, a contactor auxiliary contact acquisition interface, and an interlock drive circuit. The programmable controller generates a drive advance based on the adjacent zero-crossing times of the phase current and the historical action delay of the original gear contactor, so that the separation time of the original gear main contact falls into the low current section within the gear shift window. The interlock drive circuit blocks the target gear drive when the original gear auxiliary contact has not returned to the open state, and acquires the continuity of each phase current and the phase sequence status after the target gear is turned on, and writes the acquisition results into the operation verification status.

[0056] Specifically, the phase current zero-crossing detection interface performs sign change detection on the sampling sequence of each phase current. When continuous sampling crosses zero from the same polarity and enters the opposite polarity, a candidate zero-crossing mark is generated. Isolated reverse samples or short reverse samples during contactor bounce do not generate zero-crossing marks. The programmable controller forms a current cycle record for each phase based on adjacent candidate zero-crossing marks and calculates the local segment where the current of each phase is in a lower amplitude within the shift window. The historical action delay is generated by the time record between the original gear drive cancellation time and the auxiliary contact confirmation disconnection time. The controller sorts the most recently completed action records without bounce abnormalities, takes the middle record as the current action delay, and issues the drive command in advance relative to the local low current segment, so that the actual main contact separation falls within the local segment.

[0057] Preferably, the interlocking drive circuit uses both the programmable controller output permission and the normally closed auxiliary contact of the contactor to form a cross-blocking mechanism. When the original gear coil is still in the driving state or the original gear auxiliary contact has not been confirmed to be open, the drive path of the target gear coil remains open. The auxiliary contact acquisition interface performs continuous sampling confirmation on the contact changes and records the time stamps for the main drive cancellation, the start of auxiliary contact change, the stable opening of the contact, and the stable closing of the target contact. When the contact changes repeatedly within the confirmation interval, a bounce abnormality mark is written. After the target gear is turned on, the current sampling of each phase checks the zero-crossing sequence according to the phase sequence template and checks whether there is a missing phase current in the continuous electrical cycle. The detection results and the target auxiliary contact status are written together into the operation verification status. If any result is incompatible, the load resumes output and remains blocked.

[0058] In a preferred embodiment, the contactor's historical action delay is stored separately according to the contactor's identity, load direction, and most recent pneumatic unloading state, avoiding the mixing of action records from different mechanical contacts or under different load conditions. When a contactor lacks available historical records, the controller does not perform drive advance compensation, but instead issues a disconnect command and records the actual action delay within a longer low current candidate range. After the record is verified during operation, it is written into the delay set of the corresponding contactor. When the action delay continuously deviates from the existing record, the corresponding contactor is marked as limited reachable. The target gear selection only calls the contactor when there are no other reachable connection combinations, and expands the pneumatic load release range before calling. When the limited reachable state persists, the corresponding switching edge is isolated from the reachable connection version.

[0059] Please refer to Figure 3 The horizontal axis is segmented according to the order of the contactor's most recently completed and verified action records, while the vertical axis represents the action delay and related time. Figure 3 The actual action delay curve reflects the time record from drive cancellation to stable disconnection of auxiliary contacts. The drive advance curve represents the amount of time the controller issues an advance command to make the main contacts separate and fall into the low current section. The width of the low current section and the auxiliary confirmation time correspond to the low current amplitude section that can accommodate the disconnection action and the continuous contact confirmation process, respectively.

[0060] from Figure 3 Based on the recorded distribution, the actual action delay is mainly concentrated between 52 and 73, with the currently used median value being 60, indicating that most records can support stable advance compensation. The 7th record rises to approximately 91, exceeding the restricted observation line of 78. At the same time, the width of this low-current section is approximately 125, and the auxiliary confirmation time is approximately 104, indicating that although the controller can still find action accommodation space from the longer low-current candidate section, the contactor has already shown hysteresis characteristics that deviate from the existing records in the corresponding load direction or unloading state.

[0061] In a preferred embodiment, the programmable controller extracts relationship table update samples only from disturbance event segments that have power supply disturbance source tags, complete shift state sequences, and continuous sampling time bases. It then assembles the input voltage trajectory before shifting, the current gear, pipeline pressure, and fan speed into a pre-state record, and the target gear, the phase current sequence after shifting, the speed recovery sequence, and the actual position of the pneumatic adjustment mechanism into a post-state record. The post-state record is written into the gear load relationship table according to the adjacency relationship of the pre-state record, and event segments containing pneumatic load disturbance source tags, sensor interruption markers, or interlocking abnormality markers are stored in the isolation record area.

[0062] Specifically, the relation table update sample is generated after the running verification state is closed. The sample generation program checks whether the disturbance source label remains a power supply disturbance, whether there are unresolved versions at the event segment boundary, whether the shared time base is continuous, and whether the state sequence contains complete state markers from load release to load recovery. If any check item is not met, the event record is still saved in the original data area but is not entered into the relation table. The previous state record uses the stable segment before the original gear is disconnected as the data boundary, the input voltage trajectory retains the direction of change and continuous segments, and the pipeline pressure and speed retain the representative sequence on the same time base. The subsequent state record uses the target gear being connected to the point where the load is fully restored as the boundary, and the phase current, speed, and position data are aligned according to the contact connection marker. The previous state record and the subsequent state record are bound by the same transaction marker to prevent data from different gear shifting events from being combined.

[0063] Furthermore, the load relationship table searches for existing entries based on the index position of the previous state record. When adjacent entries exist, the new subsequent state record is compared with the existing representative trajectory for time alignment and direction consistency. If the trajectories are compatible, the new record is added to the available record set and the center sequence of the representative trajectory is updated. If the trajectories are incompatible, a branch to be verified is created without overwriting the existing entries. Events corresponding to the pneumatic load disturbance source tag enter the load isolation area, events corresponding to the sensor interruption tag enter the data integrity isolation area, and events corresponding to the interlock anomaly tag enter the execution isolation area. Each isolation area retains the original index and transaction tag. Subsequent diagnosis only allows reading isolated events and does not allow isolated events to participate in the target load retrieval, so that the update source of the relationship table is consistent with the power supply disturbance control branch.

[0064] In a preferred embodiment, when the programmable controller enters the load release state, it saves the original gear position, the original position of the pneumatic adjustment mechanism, the fan speed before gear shift, and the input voltage trajectory, forming a transaction snapshot bound to the gear shift state sequence. After the target gear position is turned on, the phase current continuity, phase sequence status, and speed change sequence are written into the same transaction record. When the operation verification state fails to obtain continuous phase current or the fan speed continues to decay, the gear execution module maintains the load release position of the pneumatic adjustment mechanism and calls the reverse interlock sequence from the target gear position to the original gear position, sequentially disconnecting the target gear position and turning on the original gear position in the subsequent low current section. When the auxiliary contact of the original gear position is abnormal, the gear shift state sequence enters the isolation shutdown state.

[0065] Specifically, the transaction snapshot is written to the non-volatile storage area before the load release command is output. The snapshot includes the event identifier, the original gear node, the original gear auxiliary contact combination, the original position of the pneumatic adjustment mechanism, the speed segment before the gear shift, and the input voltage change segment, and is supplemented with a check code generated from all fields. The pneumatic adjustment mechanism is allowed to move only after the writing is completed and the readback verification is consistent. If the readback fails, the original gear is maintained and the current gear shift window is canceled. After the target gear is turned on, the transaction record is continuously updated with verification flags to check whether the current of each phase is continuous, whether the phase sequence is consistent with the target gear, whether the speed has changed from decay to recovery, and whether the pipeline pressure is compatible with the unloading state. When all verification flags are closed, the state sequence enters the load recovery phase. If there are unclosed flags, the unloading position is maintained and a rollback request is created.

[0066] Furthermore, the reverse interlock sequence is automatically generated by the forward gear shifting edge. The controller uses the target gear as the node to be disconnected and the original gear as the node to be connected, and re-calls the phase current zero-crossing detection and historical action delay record to determine the backoff disconnection time. After the target gear auxiliary contact is confirmed to be disconnected, it checks whether the original gear auxiliary contact has the conditions to be connected. If the original gear is reachable, it issues a connection command with the original transaction mark. After the phase current is reconnected, it performs segmented recovery according to the original position of the pneumatic adjustment mechanism in the transaction snapshot. If the original gear auxiliary contact is abnormal, the original shifting edge has been isolated, or the input voltage state no longer allows the original gear to be restored, all gear drives are canceled, the pneumatic adjustment mechanism remains in the unloaded position, the state sequence enters isolation shutdown and saves the unfinished transaction, and it is prohibited to try other gears under the condition of missing contact confirmation.

[0067] In a preferred embodiment, when the controller restarts after a power outage, it reads the unclosed transactions, first verifies the transaction snapshot and collects the current auxiliary contact combination, input voltage, phase current, and pneumatic adjustment mechanism position; when the actual contact combination is consistent with the original gear and the phase current is continuous, it resumes to the running verification state; when the actual contact combination is consistent with the target gear, it continues to complete the target gear verification; when all contacts are open, it maintains pneumatic unloading and re-determines whether the original gear is reachable based on the current input voltage; when it detects that two interlocked gears are simultaneously in closed feedback, the auxiliary contact state cannot be determined, or the transaction snapshot verification fails, the controller maintains the drive output cancellation and enters the isolation shutdown record, directly connecting any gear without relying on the software output state before the interruption, and ending the unfinished transactions only after the contact combination and event data regain a consistent state.

[0068] Furthermore, after the shift transaction is closed, the programmable controller encapsulates the transaction snapshot, disturbance event segment version, shift window version, reachable connection version, and state transition record into a read-only event package. The event package saves the correspondence between control instructions and feedback data in the order of sampling time. When the relation table update program reads the event package, it verifies the power supply disturbance source label, state transition integrity, and operation verification results. Only when the verification results are consistent with the online judgment will the table entry change be submitted. If they are inconsistent, the change to be submitted will be revoked and the event package will be transferred to the execution isolation area. In maintenance mode, the state judgment can be replayed according to the timestamp in the event package, but the replay program is isolated from the field output channel. Only the expected state and expected instruction records are generated. Then, the expected records are compared with the original transaction records item by item to check whether the handling of disturbance boundaries, shift windows, and interlocking sequences is consistent after the control program version change.

[0069] Please refer to Figure 4 The horizontal axis is expanded according to the transaction replay steps, corresponding to hold, snapshot, load release, low flow confirmation, disconnection confirmation, target connection, operation verification, and load recovery in sequence. The vertical axis represents the consistency score between the replay record and the original transaction record. State sequence consistency, instruction feedback consistency, interlock sequence consistency, and verification mark closure are respectively the state transition record saved in the package, control instructions and feedback data, the original target gear interlock sequence, and the operation verification result.

[0070] Figure 4 All four curves are above the lower limit of 0.85 for verification. The interlock sequence consistency gradually decreases from approximately 0.99 to 0.944, indicating that the disconnection confirmation, target connection, and load recovery phases maintain clear sequential constraints. The state sequence consistency decreases from 0.995 to 0.918, reflecting that the playback process can reproduce the original closed-loop state path, but the latter part will be slightly different due to the influence of the recovery observation segment and version boundary extension. The verification mark closure is approximately 0.892 at the load recovery point, which is the lowest among the four types of curves, suggesting that the final recovery phase needs to focus on checking whether all marks such as current continuity, phase sequence, speed recovery, and pressure compatibility are closed.

[0071] In this embodiment, the programmable controller's software tasks are scheduled according to the dependencies of sampling and writing, event recognition, window calculation, state execution, and record submission. The sampling and writing task only updates the circular buffer and time index, the event recognition task reads the closed sampling interval, the window calculation task reads the versioned event state and pneumatic support state, and the state execution task only accepts control objects that have locked target gears and transaction markers. Data is transferred between different tasks through immutable state snapshots. New sampling will not rewrite the event version referenced by the currently executing transaction, and the contact time markers generated by state execution are returned to the event recognition task in an append manner. The control output adopts a single write channel. Pneumatic adjustment commands and gear drive commands are both submitted by the state execution task. The protection input can cancel the gear drive but cannot bypass the interlock condition to directly connect other gears, so that the data processing logic, state transition logic, and field output maintain a traceable sequential relationship.

[0072] In a preferred embodiment, before the system is put into operation, initial reference data is established when there is no power supply disturbance and the pipeline is under a verifiable load condition. The controller maintains a legal gear position and a stable pneumatic adjustment position, continuously collecting input voltage, phase current, speed, air volume, and pipeline pressure, and writing continuous segments without protection actions, contact changes, and sensor interruptions into the initial reference area. Subsequently, the position of the damper or guide vane is changed within the allowable pneumatic adjustment position range, and a corresponding pneumatic load record is formed after each position stabilizes, but the pressure adjustment gear is not automatically changed during the commissioning process. The wiring relationship, auxiliary contact combination, and phase sequence status of each legal gear position are written into the reachable connection version through no-load verification, and the gear records that have been verified by field operation are gradually replaced by the initial reference records. The initial reference area is only used to generate noise bands, speed termination boundaries, and actuator action trajectories when historical events are lacking, and is not directly written into the gear load relationship table as a successful gear shift record.

[0073] Specifically, when the input voltage continuously decreases while the pipeline pressure has not changed beforehand, the voltage node enters the power supply event queue. The phase current node and speed node are connected to the voltage node in chronological order, and the controller locks the power supply disturbance source tag accordingly. The speed decay sequence generates the rotor inertia support range, and the remaining stroke of the pneumatic regulating mechanism and the pressure response record generate the load release range. The two ranges overlap and are written into the shift window. The state sequence switches to load release and continuously collects position, pressure and current. After the unloading state is confirmed, the original gear disconnection command is issued based on the zero-crossing record and the contactor action delay. After the auxiliary contact is stably disconnected, the reachable gear corresponding to the voltage drop direction is connected. After the phase current continuity, phase sequence and speed recovery sequence after the target gear is engaged are verified, the pneumatic regulating mechanism returns to the original load position according to the position range. The complete transaction is submitted to the relationship table as a power supply disturbance sample. If any verification condition is not closed, the unloading is maintained and reverse interlocking is executed.

Claims

1. An industrial control system for wide voltage adaptive operation of wind turbines, characterized in that, It includes a data acquisition module connected to the wind turbine inlet circuit and the operating side, and a programmable controller connected to the data acquisition module. The programmable controller is also connected to the gear execution module of the multi-gear pressure regulation circuit and the pneumatic adjustment mechanism. The data acquisition module synchronously acquires electrical status data consisting of input voltage trajectory and motor phase current, as well as machine-air status data consisting of fan speed and pipeline pressure. The programmable controller generates a disturbance persistence state based on the temporal coupling of two types of state data, and maps the fan speed and pipeline pressure to a machine-air support state that constrains the disturbance persistence state. The target gear and shift window are determined by the machine-air support state. The gear shifting module adjusts the pneumatic regulating mechanism according to the shifting window and switches the multi-gear pressure regulating circuit in an interlocking sequence of first disconnecting and then closing.

2. The industrial control system for wide voltage adaptive operation of a fan according to claim 1, characterized in that, The data acquisition module is equipped with a common time base covering voltage sampling, phase current sampling and speed sampling, and writes the pipeline pressure sampling value and the position of the pneumatic regulating mechanism into the corresponding time base interval; The programmable controller establishes a disturbance event segment based on the starting point of the input voltage trajectory change, aligns the starting point of the phase current change, the starting point of the fan speed change, and the starting point of the pipeline pressure change to the disturbance event segment in sequence, and generates a power supply disturbance identifier or a pneumatic load disturbance identifier based on the order and direction of each change starting point. The disturbance duration is generated by the continuous event segment corresponding to the power supply disturbance identifier.

3. An industrial control system for wide voltage adaptive operation of a fan according to claim 2, characterized in that, The programmable controller extracts the continuous change sequence of the fan speed from the disturbance event segment, and combines it with the current pipeline pressure and the movable stroke of the pneumatic regulating mechanism to generate the rotor inertia support range and the load release range. The time range corresponding to the rotor inertia support range, the load release range and the disturbance duration state are overlapped to form a shift window that allows the gear to be disconnected and connected. Select the target gear corresponding to the current input voltage direction and pipeline pressure status from the reachable connection combinations of the multi-level voltage regulation circuit, and associate the target gear with the gear shift window.

4. An industrial control system for wide voltage adaptive operation of a fan according to claim 1, characterized in that, The programmable controller is configured with a shift state sequence that switches between hold, load release, disconnection confirmation, target gear activation, operation verification, and load recovery. After entering the load release state, the gear execution module moves the pneumatic adjustment mechanism to the position corresponding to the load release state, and cancels the original gear drive after the phase current enters the shift window; After the auxiliary contact of the original gear returns to the off state, the gear execution module connects to the target gear and completes the conversion between the operation verification state and the load recovery state based on the switched phase current, fan speed and pipeline pressure.

5. An industrial control system for wide voltage adaptive operation of a fan according to claim 1, characterized in that, The programmable controller intercepts a reference data segment without gear operation instructions before each disturbance event segment, and establishes a change difference sequence between the reference data segment and the input voltage, phase current, fan speed and pipeline pressure in the disturbance event segment. Using input voltage, phase current, fan speed, and pipeline pressure as event nodes, and the transmission order and direction of change of the starting point of change as the node connection relationship, a disturbance propagation chain is formed. A disturbance source tag is generated based on the first event node and the order of subsequent nodes in the disturbance propagation chain, and the electrical transient segment formed by the contactor action is removed from the disturbance propagation chain using the time stamp of the gear operation command.

6. An industrial control system for wide voltage adaptive operation of a fan according to claim 3, characterized in that, The programmable controller establishes a power supply event queue representing the continuous deviation of the input voltage and a mechanical event queue representing the continuous decay of the fan speed. When the input voltage briefly returns while the phase current and fan speed have not yet recovered to the corresponding reference data segment, the adjacent power supply events are kept continuous within the same disturbance event segment. When the pipeline pressure changes before the phase current changes, the corresponding segment will be transferred to the pneumatic load disturbance flag. The disturbance persistence state is generated by the overlapping range of the power supply event queue and the mechanical event queue, and is written into the shift window record together with the load release interval.

7. An industrial control system for wide voltage adaptive operation of a fan according to claim 3, characterized in that, The data acquisition module also collects the air volume and the actual position of the pneumatic adjustment mechanism. The programmable controller establishes a gear load relationship table indexed by the current gear, disturbance source label, and pneumatic load status. Each entry is associated with the reachable connection combination of multiple voltage regulation circuits, the fan speed before shifting, the phase current sequence after shifting, the speed recovery sequence, and the movable stroke of the pneumatic adjustment mechanism. The target tier is selected from the reachable join combination that matches the current index and has a complete runtime verification record. If no matching table entry is found, a candidate tier sequence is constructed according to the adjacent reachable join combination.

8. An industrial control system for wide voltage adaptive operation of a fan according to claim 4, characterized in that, The gear position execution module includes a phase current zero-crossing detection interface, a contactor auxiliary contact acquisition interface, and an interlock drive circuit. The programmable controller generates a drive advance based on the adjacent zero-crossing times of the phase current and the historical action delay of the original gear contactor, so that the separation time of the original gear main contact falls into the low current section of the shift window. The interlock drive circuit blocks the target gear drive when the original gear auxiliary contact has not returned to the open state, and collects the continuity of each phase current and the phase sequence status after the target gear is turned on, and writes the collection results into the operation verification status.

9. An industrial control system for wide voltage adaptive operation of a fan according to claim 7, characterized in that, The programmable controller extracts relation table update samples only from disturbance event segments with power supply disturbance source tags, complete shift state sequences and continuous sampling time bases. It combines the input voltage trajectory before shift, the current gear, pipeline pressure and fan speed into a pre-state record, and the target gear, the phase current sequence after shift, the speed recovery sequence and the actual position of the pneumatic adjustment mechanism into a post-state record. Write the subsequent state records into the gear load relationship table according to the adjacency relationship of the preceding state records, and store the event segments containing aerodynamic load disturbance source tags, sensor interruption tags, or interlock anomaly tags into the isolation record area.

10. An industrial control system for wide voltage adaptive operation of a fan according to claim 8, characterized in that, When the programmable controller enters the load release state, it saves the original gear position, the original position of the pneumatic adjustment mechanism, the fan speed before the gear shift, and the input voltage trajectory, forming a transaction snapshot bound to the gear shift state sequence. After the target gear is turned on, the phase current continuity, phase sequence status and speed change sequence are written into the same transaction record; When the operation verification state does not obtain continuous phase current or the fan speed continues to decline, the gear execution module maintains the load release position of the pneumatic adjustment mechanism and calls the reverse interlock sequence from the target gear to the original gear, and sequentially disconnects the target gear and connects the original gear in the subsequent low current section. When the original gear auxiliary contact is abnormal, the gear shift state sequence enters the isolation shutdown state.

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