A power supply and motor drive integrated control system for a cooking machine

Abstract

The application relates to the field of electric control technology of cooking equipment, and discloses a power supply and motor drive integrated control system for a cooking machine, which comprises the following steps: acquiring direct-current bus voltage, bus current, single-resistance sampling value, three-phase inverter bridge switch state, rotor position and rotation speed feedback data, reconstructing three-phase phase current based on an SVPWM effective vector interval, establishing a unified basis for the state of the power supply side and the driving side, determining a power supply side change segment according to torque current, bus voltage and bus current, combining rotation speed feedback data to determine a driving side change segment, forming a power supply driving time sequence relationship through sampling time overlap, generating a PFC duty adjustment amount, an SVPWM zero vector distribution amount and a PWM blocking period based on the relationship, thereby reducing the influence of strong electric interference and load mutation, improving the bus power supply and motor drive collaboration, and guaranteeing the motor rotation speed stability.

Description

Technical Field

[0001] This invention relates to the field of electrical control technology for cooking equipment, and more specifically, to an integrated power supply and motor drive control system for a stir-fry machine. Background Technology

[0002] The power supply and motor drive control of a cooking machine are used in scenarios such as power conversion of cooking equipment, driving of stirring motors, and maintaining stir-frying speed. They are usually constrained by internal space, power density, heat dissipation path and control delay. Existing technologies usually use independent control of power conversion, independent control of motor drive, local state judgment, segmented power adjustment, time smoothing and protection screening to achieve operation control. This type of method is usually suitable for application scenarios where the coupling between the power supply side and the drive side is weak, the load change is gradual and the internal electromagnetic interference is controllable.

[0003] During the operation of the cooking machine, high-current switching interference and sudden changes in the stir-fry load can alter the stable state of the bus voltage and the transmission state of the drive signal. These factors make it difficult for the control method based on independent power conversion control, independent motor drive control, and local state judgment to maintain the same control benchmark between the bus power supply state and the motor drive state, resulting in a decrease in motor speed stability. Therefore, the technical problem that needs to be solved is how to enhance the bus drive coordination and ensure motor speed stability while reducing the impact of strong electrical interference.

[0004] In view of this, the present invention proposes an integrated power supply and motor drive control system for a cooking machine to solve the above problems. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides an integrated power supply and motor drive control system for a cooking machine.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An integrated power supply and motor drive control system for a cooking machine is provided, comprising: Current Reconstruction Module: Used to acquire DC bus voltage, bus current, single resistor sampling value, three-phase inverter bridge switch status, rotor position, heat sink temperature and speed feedback data. Based on the SVPWM effective vector interval corresponding to the three-phase inverter bridge switch status, the single resistor sampling value is written into the phase current channel to obtain the three-phase phase current. Power sensing module: used to perform coordinate transformation of three-phase current based on rotor position to obtain torque current, and to determine the power supply side change segment based on DC bus voltage, bus current and torque current; Drive fusion module: used to determine the drive-side change segment based on torque current and speed feedback data, and to overlap the power supply-side change segment with the drive-side change segment according to the sampling time to obtain the power supply drive timing relationship; Integrated control module: used to generate PFC duty cycle adjustment and SVPWM zero vector allocation based on power drive timing relationship, DC bus voltage and torque current, and generate PWM lockout cycle according to heat sink temperature, bus current and three-phase phase current.

[0007] In some embodiments, based on the SVPWM effective vector interval corresponding to the three-phase inverter bridge switching state, the single-resistor sample value is written into the phase current channel to obtain the three-phase phase current, including: Read the upper and lower bridge arm conduction phases in the three-phase inverter bridge switch states, and read the start and end boundaries of the SVPWM effective vector interval to form a switch interval correspondence table; Match the conducting phase of the bridge arm in the switch interval correspondence table with the direction of the bus current to obtain the sampling channel correspondence table; The sampling channel correspondence table is consulted according to the sampling time of the single resistor sampling value, and the single resistor sampling value is written into the phase current channel recorded in the sampling channel correspondence table. The unwritten phase current channels are supplemented according to the constraint relationship that the phase currents already written into the channel and the total three-phase current is zero, so as to obtain the three-phase current.

[0008] In some embodiments, the bridge arm conduction phase in the switch interval correspondence table is matched with the bus current direction to obtain the sampling channel correspondence table, including: Read the SVPWM effective vector interval where the sampling time is located in the table corresponding to the switching interval, and extract the upper bridge arm conduction phase and the lower bridge arm conduction phase corresponding to the SVPWM effective vector interval; Based on the direction of the bus current, mark the current inflow phase and the current outflow phase in the upper and lower bridge arm conducting phases, and assign the current inflow phase and the current outflow phase to the phase current channel respectively to form channel candidates. Based on the direction of the bus current within the effective vector interval of the SVPWM where the single resistor sampling value is located, the phase current channel corresponding to the single resistor sampling value is selected from the channel candidates to obtain the sampling channel correspondence table.

[0009] In some embodiments, determining the power supply side variation segment based on DC bus voltage, bus current, and torque current includes: The DC bus voltages are arranged according to the sampling time, and the voltage change segments are divided according to the rise and fall relationship between adjacent sampling points; Read the bus current direction switching position within the voltage change segment, and mark the voltage change segment containing the bus current direction switching position as the bus current response segment; The positions of torque current increase / decrease are filled back into the bus current response segment, and the segment boundary is truncated according to the sampling order of torque current increase / decrease position and bus current direction switching position to obtain the power supply side change segment.

[0010] In some embodiments, reading the bus current direction switching position within a voltage change segment and marking the voltage change segment containing the bus current direction switching position as a bus current response segment includes: Read the current direction of adjacent sampling points of the bus current within the voltage change segment, and mark the sampling points where the current direction changes as the bus current direction switching positions; The bus current direction switching position is backfilled into the corresponding voltage change segment according to the sampling time, and the voltage change segment containing the bus current direction switching position is retained. By extracting the DC bus voltage, bus current, and torque current from the start and end boundaries of the retained voltage change segment, the bus current response segment is obtained.

[0011] In some embodiments, determining the drive-side variation segment based on torque current and speed feedback data includes: The torque current is arranged according to the sampling time, and the torque current change segments are divided according to the increase or decrease relationship between adjacent sampling points; Read the response position of the speed feedback data within the torque current change segment, and mark the torque current change segment containing the response position of the speed feedback data as the speed response segment; The torque current increase / decrease relationship within the speed response segment is correlated with the response position of the speed feedback data according to the sampling time, and the segment boundary is truncated according to the corresponding sampling range to obtain the drive-side change segment.

[0012] In some embodiments, reading the response position of speed feedback data within a torque current change segment, and marking the torque current change segment containing the response position of speed feedback data as a speed response segment, includes: Read the rise and fall relationship between adjacent sampling points of speed feedback data within the torque current change segment, and mark the sampling point where the rise and fall relationship switches as the response position of speed feedback data; The response position of the speed feedback data is backfilled into the corresponding torque current change segment according to the sampling time, and the torque current change segment containing the response position of the speed feedback data is retained. The torque current and speed feedback data are extracted according to the start and end boundaries of the retained torque current change segment to obtain the speed response segment.

[0013] In some embodiments, based on power drive timing relationships, DC bus voltage, and torque current, PFC duty cycle adjustment and SVPWM zero vector allocation are generated, including: Read the starting boundaries of the power supply side change segment and the starting boundaries of the drive side change segment in the power supply drive timing relationship, and determine the control sequence relationship based on the sampling order of the starting boundaries; The PFC duty cycle adjustment direction is determined based on the control sequence and the rise and fall of the DC bus voltage; the SVPWM zero vector movement direction is determined based on the control sequence and the increase and decrease of the torque current. Write the PFC duty cycle adjustment direction into the interleaved parallel Boost control cycle, and write the SVPWM zero vector movement direction into the three-phase inverter bridge control cycle to generate the PFC duty cycle adjustment amount and the SVPWM zero vector allocation amount.

[0014] In some embodiments, the PFC duty cycle adjustment direction is determined based on the control sequence and the rise / fall relationship of the DC bus voltage, including: Read the power supply side precedence marker or drive side precedence marker in the control sequence, and read the rise and fall relationship of the DC bus voltage within the power supply side change segment; When the control sequence is marked with the power supply side first, the rise and fall of the DC bus voltage is mapped to the interleaved parallel Boost control cycle. When the control sequence is marked with the drive side first, the increase and decrease of the torque current in the change segment on the drive side is mapped to the interleaved parallel Boost control cycle. The PFC duty cycle adjustment direction is determined based on the corresponding results within the interleaved parallel Boost control cycle.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention acquires DC bus voltage, bus current, single-resistor sampling values, three-phase inverter bridge switch status, rotor position, heat sink temperature, and speed feedback data. Based on the effective vector range of SVPWM, it reconstructs the three-phase current, providing a unified sampling basis for the power supply and drive side states. Then, based on the rotor position, it performs coordinate transformation on the three-phase current to obtain the torque current. Combining the bus voltage and bus current, it determines the power supply-side variation segments, and simultaneously, based on the torque current and speed feedback data, it determines the drive-side variation segments, establishing a correspondence between power supply changes and motor load changes. Furthermore, it overlaps these two types of variation segments according to sampling time to form a power supply drive timing relationship, thereby generating PFC duty cycle adjustment, SVPWM zero vector allocation, and PWM lockout period. This reduces the impact of strong electrical interference and sudden load changes, improves the coordination between bus power supply and motor drive, and ensures motor speed stability. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the integrated power supply and motor drive control system for a cooking machine according to the present invention. Figure 2This is a flowchart illustrating an integrated power supply and motor drive control method for a cooking machine according to the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. In the following detailed description, many specific details are set forth to provide a thorough understanding of the exemplary embodiments described. However, it will be apparent to those skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other exemplary embodiments, well-known structures have not been described in detail to avoid unnecessarily obscuring the concepts of this disclosure. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention. Furthermore, the various aspects described in the embodiments may be combined arbitrarily without conflict.

[0018] The user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0019] Example 1

[0020] Figure 1 This disclosure illustrates an integrated power supply and motor drive control system for a cooking machine, provided in at least one embodiment, comprising: Current Reconstruction Module: Used to acquire DC bus voltage, bus current, single resistor sampling value, three-phase inverter bridge switch status, rotor position, heat sink temperature and speed feedback data. Based on the SVPWM effective vector interval corresponding to the three-phase inverter bridge switch status, the single resistor sampling value is written into the phase current channel to obtain the three-phase phase current. In this embodiment, the DC bus voltage is the voltage across the DC bus formed after the AC input has been corrected for power factor. The bus current is the current when the DC bus supplies power to the three-phase inverter bridge. The single resistor sampling value is the current sampling result output by the sampling resistor set on the DC bus or the common circuit of the inverter bridge. The three-phase inverter bridge switching state is the conduction state of each upper and lower bridge arm in the three-phase inverter bridge within the same control cycle. The rotor position is the electrical angle position of the motor rotor within the current control cycle. The heat sink temperature is the temperature collected by the heat sink of the power device. The speed feedback data is the speed detection result of the stirring motor or the speed result obtained from the change of rotor position.

[0021] It is understandable that during the stir-frying process, the weight of the ingredients, their adhesion, and the stirring resistance will cause changes in the motor load. The switching action of the three-phase inverter bridge will also create strong switching interference within the same circuit board. If the single resistor sample value is directly used as the current of a certain phase, the current sampling result may not correspond to the actual conducting phase. Therefore, this embodiment does not read the phase current separately, but combines the switching state of the three-phase inverter bridge and the effective vector range of SVPWM to determine the phase current channel to which the single resistor sample value should be assigned, so that the single resistor sample value corresponds to the conduction path of the inverter bridge at that time.

[0022] It should be noted that, through the above processing, the three-phase current is not directly acquired by three independent phase current sensors, but is formed by writing the single resistor sampling value into the corresponding phase current channel in different SVPWM effective vector intervals. This reduces the number of current sampling hardware components and allows subsequent torque current calculation, power supply side change segment judgment, and drive side change segment judgment to be based on the same set of current data.

[0023] Based on the effective vector interval of SVPWM corresponding to the switching states of the three-phase inverter bridge, the sampled value of a single resistor is written into the phase current channel to obtain the three-phase phase current, including: Read the upper and lower bridge arm conduction phases in the three-phase inverter bridge switch states, and read the start and end boundaries of the SVPWM effective vector interval to form a switch interval correspondence table; Match the conducting phase of the bridge arm in the switch interval correspondence table with the direction of the bus current to obtain the sampling channel correspondence table; The sampling channel correspondence table is consulted according to the sampling time of the single resistor sampling value, and the single resistor sampling value is written into the phase current channel recorded in the sampling channel correspondence table. The unwritten phase current channels are supplemented according to the constraint relationship that the phase currents already written into the channel and the total three-phase current is zero, so as to obtain the three-phase current.

[0024] Furthermore, the switch interval correspondence table records the correspondence between each SVPWM effective vector interval and the bridge arm conduction phase within the same control cycle. The start and end boundaries of the SVPWM effective vector interval can be determined by the action time of the effective vector within the control cycle. The upper and lower bridge arm conduction phases can be determined by the drive signal of the three-phase inverter bridge. For example, in a certain effective vector interval, if the upper bridge arm of phase A is conducting and the lower bridge arm of phase B is conducting, then the DC bus current flows through the relevant loops of phase A and phase B in that interval.

[0025] In this embodiment, the sampling channel correspondence table records the correspondence between the single resistor sampling value and the phase current channel. This correspondence is not fixed, but is determined by the bridge arm conducting phase and the bus current direction. For example, when the bus current direction indicates that the current flows from the positive end of the DC bus into the upper bridge arm conducting phase and returns to the negative end of the DC bus through the lower bridge arm conducting phase, the single resistor sampling value corresponds to the current channel of the inflow phase and the current channel of the outflow phase, respectively. Subsequently, the current of the remaining phases is supplemented by the constraint that the total of the three-phase currents is zero.

[0026] It is understandable that the three-phase currents of a three-phase motor at the same moment satisfy the current constraint that the total current is zero. Therefore, within the same control cycle, after the current corresponding to the single resistor sampling value has been written into two phase current channels, the remaining phase current channels can be supplemented according to the two phase currents that have been written, thereby forming a three-phase current. This three-phase current can be directly entered into the subsequent coordinate transformation process, avoiding the torque current calculation deviation caused by the mismatch between the single resistor sampling value and the inverter bridge conduction path.

[0027] Matching the conducting phases of the bridge arms in the switch interval correspondence table with the direction of the bus current yields the sampling channel correspondence table, including: Read the SVPWM effective vector interval where the sampling time is located in the table corresponding to the switching interval, and extract the upper bridge arm conduction phase and the lower bridge arm conduction phase corresponding to the SVPWM effective vector interval; Based on the direction of the bus current, mark the current inflow phase and the current outflow phase in the upper and lower bridge arm conducting phases, and assign the current inflow phase and the current outflow phase to the phase current channel respectively to form channel candidates. Based on the direction of the bus current within the effective vector interval of the SVPWM where the single resistor sampling value is located, the phase current channel corresponding to the single resistor sampling value is selected from the channel candidates to obtain the sampling channel correspondence table.

[0028] It should be noted that the effective vector interval of SVPWM at the sampling time determines the inverter bridge conduction path corresponding to the current single resistor sampling value. The direction of the bus current determines the current inflow and outflow direction in this conduction path. Together, they determine the phase current channel that the single resistor sampling value should be written into. If the phase current channel is determined only based on the conduction phase of the bridge arm, the phase sign may be reversed when the current direction changes or energy feedback occurs.

[0029] Furthermore, the channel candidates may include the phase current channel corresponding to the current flowing into the phase and the phase current channel corresponding to the current flowing out of the phase. The direction of the bus current within the effective vector interval of the SVPWM where the single resistor sampling value is located is used to determine the actual write channel from the channel candidates. For example, when the load suddenly increases, the torque demand will change the position of the bus current direction change. In this embodiment, the channel candidates are selected by the direction of the bus current so that the sampling channel correspondence table can reflect the actual current path within the current control cycle.

[0030] In this embodiment, after the sampling channel correspondence table is generated, the single resistor sampling value can be written into the corresponding phase current channel according to the sampling time, instead of being written into the phase current channel according to a fixed phase sequence. This keeps the three-phase phase current associated with the SVPWM effective vector range, the three-phase inverter bridge switch state and the bus current direction, providing a data basis for obtaining the torque current based on the three-phase phase current.

[0031] Power sensing module: used to perform coordinate transformation of three-phase current based on rotor position to obtain torque current, and to determine the power supply side change segment based on DC bus voltage, bus current and torque current; In this embodiment, the torque current is the current component obtained after coordinate transformation of the three-phase phase current with the rotor position involved. The torque current is used to characterize the current change state corresponding to the motor output torque. The power supply side change segment is the continuous rise and fall of the DC bus voltage, and this continuous rise and fall change is related to the sampling time of the bus current direction change and the torque current change. By converting the three-phase phase current into torque current, the load change on the motor side can participate in the bus side change judgment in the form of current component, instead of relying solely on the fluctuation of the DC bus voltage itself to determine the power supply state.

[0032] It is understandable that during the stir-frying process, when the stirring motor encounters food accumulation or resistance from the pot wall, the torque current will first reflect the change in motor load, and then the DC bus voltage and bus current will also change accordingly. If only the rise and fall of the DC bus voltage is used as the basis for the power supply side change, it is easy to mistake switching noise or short-time ripple for the power supply side change. Therefore, this embodiment uses the DC bus voltage, bus current and torque current together to determine the power supply side change segment, so that the power supply side change segment can reflect the correspondence between the bus power supply status and the motor torque demand.

[0033] The power supply side variation segments are determined based on DC bus voltage, bus current, and torque current, including: The DC bus voltages are arranged according to the sampling time, and the voltage change segments are divided according to the rise and fall relationship between adjacent sampling points; Read the bus current direction switching position within the voltage change segment, and mark the voltage change segment containing the bus current direction switching position as the bus current response segment; The positions of torque current increase / decrease are filled back into the bus current response segment, and the segment boundary is truncated according to the sampling order of torque current increase / decrease position and bus current direction switching position to obtain the power supply side change segment.

[0034] Furthermore, the voltage change segment is a continuous sampling range divided according to the rise and fall relationship of the DC bus voltage between adjacent sampling points. This continuous sampling range is used to define the time boundary where the bus voltage change occurs. The bus current direction switching position is the sampling position where the bus current changes from the inflow direction to the outflow direction or from the outflow direction to the inflow direction within the voltage change segment. The bus current direction switching position can reflect the moment when the energy flow direction between the DC bus and the three-phase inverter bridge changes.

[0035] It should be noted that filling the torque current increase / decrease position back into the bus current response segment means writing the position of the increase / decrease of the torque current at the sampling time into the voltage change segment that already includes the bus current direction switching position. This allows the same segment to simultaneously retain the DC bus voltage change, the bus current direction change, and the torque current change. Then, based on the sampling order of the torque current increase / decrease position and the bus current direction switching position, the segment boundary is truncated. This can reduce a simple voltage fluctuation segment into a power supply side change segment that is related to the motor torque demand.

[0036] Read the bus current direction switching position within the voltage change segment, and mark the voltage change segment containing the bus current direction switching position as the bus current response segment, including: Read the current direction of adjacent sampling points of the bus current within the voltage change segment, and mark the sampling points where the current direction changes as the bus current direction switching positions; The bus current direction switching position is backfilled into the corresponding voltage change segment according to the sampling time, and the voltage change segment containing the bus current direction switching position is retained. By extracting the DC bus voltage, bus current, and torque current from the start and end boundaries of the retained voltage change segment, the bus current response segment is obtained.

[0037] In this embodiment, the current direction can be determined based on the sampling polarity of the bus current or the energy flow direction corresponding to the bus current. The sampling point where the current direction changes is used to indicate the location where the DC bus supplies power to the three-phase inverter bridge changes. After filling the bus current direction change location back into the corresponding voltage change segment, segments that only have voltage rise and fall but do not include changes in the bus current direction can be excluded, thereby retaining the voltage change segments related to changes in the bus energy flow direction.

[0038] Furthermore, the DC bus voltage, bus current, and torque current are extracted according to the start and end boundaries of the retained voltage change segments in order to ensure that the three types of data are within the same sampling time range. For example, when a bus current direction switching position occurs within a certain voltage change segment, the DC bus voltage, bus current, and torque current are simultaneously extracted between the start and end boundaries of the segment. This yields a bus current response segment that includes bus voltage changes, bus current direction switching, and torque current changes, providing a unified segment basis for subsequently determining power supply side change segments.

[0039] It should be noted that the bus current response segment is not simply a combination of any voltage change segment and any bus current direction switching position. Instead, it needs to meet the binding and screening rules between voltage fluctuation and current direction switching. Specifically, the voltage change segment corresponds to the candidate fluctuation range in which the DC bus voltage forms a continuous increase or decrease between adjacent sampling points, and the bus current direction switching position corresponds to the sampling position where the energy flow direction between the DC bus and the three-phase inverter bridge changes. Only when the bus current direction switching position is located between the start boundary and the end boundary of the voltage change segment, and the sampling interval between the bus current direction switching position and the start boundary or peak position of the voltage change segment does not exceed the preset binding time window, is the voltage change segment retained as a bus current response segment.

[0040] Furthermore, if multiple bus current direction switching positions exist within a voltage change segment, the bus current direction switching position with the smallest sampling interval to the starting boundary of the voltage change segment or the position with the largest voltage change amplitude is preferentially selected as the binding position. If the bus current direction switching position falls within the voltage change segment, but the interval between it and the voltage fluctuation start point is too large, or the change in bus current amplitude before and after the current direction switching does not reach the preset current switching threshold, then the voltage change segment is not marked as a bus current response segment. Thus, the continuous rise and fall relationship of DC bus voltage corresponds to the voltage fluctuation candidate range, the bus current direction switching position corresponds to the basis for energy flow direction change, and the preset binding time window and preset current switching threshold correspond to the screening conditions for whether the two are effectively bound, thereby avoiding misjudging switching ripple, short-time voltage noise, or irrelevant current zero crossing as power supply side changes.

[0041] Drive fusion module: used to determine the drive-side change segment based on torque current and speed feedback data, and to overlap the power supply-side change segment with the drive-side change segment according to the sampling time to obtain the power supply drive timing relationship; In this embodiment, the driving-side change segment is a segment in which the torque current continuously increases or decreases, and this continuous increase or decrease is related to the sampling time of the response position of the speed feedback data. The power supply driving timing relationship is the sequential relationship and overlap relationship between the power supply-side change segment and the driving-side change segment at the sampling time. The torque current is used to reflect the current change corresponding to the motor output torque, and the speed feedback data is used to reflect the change in the actual speed of the stirring motor. Therefore, by determining the driving-side change segment based on the torque current and speed feedback data, the motor current change and the actual speed response can be analyzed within the same sampling time range.

[0042] It is understandable that during the stir-frying process of a cooking machine, when the stirring motor encounters changes in the resistance of the food, the torque current usually increases or decreases first. The speed feedback data then reflects the speed increase or decrease or the speed recovery. If the state of the drive side is judged solely by the speed feedback data, it is easy to miss the interval where the torque current has changed but the speed has not yet responded. If the state of the drive side is judged solely by the torque current, it is difficult to distinguish between the current disturbance caused by changes in effective load and switching interference. In this embodiment, the torque current change segment is combined with the response position of the speed feedback data to obtain the drive side change segment. Then, the drive side change segment and the power supply side change segment are overlapped according to the sampling time to determine the timing correspondence between the bus power supply change and the motor drive change.

[0043] Based on torque current and speed feedback data, the drive-side variation segments are determined, including: The torque current is arranged according to the sampling time, and the torque current change segments are divided according to the increase or decrease relationship between adjacent sampling points; Read the response position of the speed feedback data within the torque current change segment, and mark the torque current change segment containing the response position of the speed feedback data as the speed response segment; The torque current increase / decrease relationship within the speed response segment is correlated with the response position of the speed feedback data according to the sampling time, and the segment boundary is truncated according to the corresponding sampling range to obtain the drive-side change segment.

[0044] Furthermore, the torque current change segment is a continuous sampling range divided according to the increase or decrease relationship of torque current between adjacent sampling points. This continuous sampling range is used to define the time boundary where the change in motor torque demand occurs. The response position of the speed feedback data is the sampling position where the speed feedback data shows a switching relationship between increase and decrease within the torque current change segment. This response position can reflect the moment when the stirring motor speed responds to the change in torque current.

[0045] It should be noted that placing the response position of the speed feedback data within the torque current change segment is to confirm whether the actual speed has changed accordingly within the same torque current change range. Subsequently, the torque current increase / decrease relationship is correlated with the response position of the speed feedback data according to the sampling time. This can compress the simple current disturbance segment into a drive-side change segment related to the speed response, so that the subsequent power supply drive timing relationship no longer comes only from the current change, but also includes both torque demand and speed response information.

[0046] The response position of the speed feedback data is read within the torque current change segment, and the torque current change segment containing the response position of the speed feedback data is marked as the speed response segment, including: Read the rise and fall relationship between adjacent sampling points of speed feedback data within the torque current change segment, and mark the sampling point where the rise and fall relationship switches as the response position of speed feedback data; The response position of the speed feedback data is backfilled into the corresponding torque current change segment according to the sampling time, and the torque current change segment containing the response position of the speed feedback data is retained. The torque current and speed feedback data are extracted according to the start and end boundaries of the retained torque current change segment to obtain the speed response segment.

[0047] In this embodiment, the rise and fall relationship of the speed feedback data can be determined by the direction of speed change of adjacent sampling points. The sampling point where the rise and fall relationship changes indicates the position where the stirring motor changes from acceleration to deceleration or from deceleration to acceleration. After filling the response position of the speed feedback data back into the corresponding torque current change segment, segments that only have torque current change but no speed response can be excluded, thereby retaining the torque current change segment related to the actual operating state of the motor.

[0048] Furthermore, extracting torque current and speed feedback data according to the start and end boundaries of the retained torque current change segments is to ensure that the torque current and speed feedback data correspond within the same sampling time range. For example, when the response position of speed feedback data appears within a certain torque current change segment, the torque current and speed feedback data are extracted synchronously between the start and end boundaries of that segment. This yields a speed response segment that includes changes in torque demand and speed response, providing a segment basis for subsequently obtaining drive-side change segments.

[0049] Integrated control module: used to generate PFC duty cycle adjustment and SVPWM zero vector allocation based on power drive timing relationship, DC bus voltage and torque current, and generate PWM lockout cycle according to heat sink temperature, bus current and three-phase phase current.

[0050] In this embodiment, the power drive timing relationship is used to represent the sequential correspondence between the power supply side change segment and the drive side change segment at the sampling time. The PFC duty cycle adjustment is the duty cycle correction amount written into the interleaved parallel Boost control cycle. The SVPWM zero vector allocation is the zero vector action interval adjustment amount written into the three-phase inverter bridge control cycle. The PWM blocking cycle is the control cycle in which the three-phase inverter bridge stops outputting PWM control signals in the protection state. By applying the power drive timing relationship to both the PFC duty cycle adjustment and the SVPWM zero vector allocation, the DC bus power supply change and the motor drive change can be processed under the same control cycle system.

[0051] Understandably, when a stir-fry machine experiences a sudden change in load, if the change on the power supply side precedes the change on the drive side, it usually indicates that the DC bus power supply status has changed, requiring priority adjustment of the PFC side control. If the change on the drive side precedes the change on the power supply side, it usually indicates that the motor torque demand changes first, requiring constraints on subsequent PFC duty cycle adjustment and SVPWM zero vector allocation based on the torque current change. At the same time, the heat sink temperature, bus current, and three-phase current together reflect the thermal state of the power devices, the bus power supply status, and the motor phase current status, and can therefore be used to generate PWM lockout cycles, avoiding protection judgments based solely on a single temperature or a single current.

[0052] Based on the power drive timing relationship, DC bus voltage, and torque current, PFC duty cycle regulation and SVPWM zero vector allocation are generated, including: Read the starting boundaries of the power supply side change segment and the starting boundaries of the drive side change segment in the power supply drive timing relationship, and determine the control sequence relationship based on the sampling order of the starting boundaries; The PFC duty cycle adjustment direction is determined based on the control sequence and the rise and fall of the DC bus voltage; the SVPWM zero vector movement direction is determined based on the control sequence and the increase and decrease of the torque current. Write the PFC duty cycle adjustment direction into the interleaved parallel Boost control cycle, and write the SVPWM zero vector movement direction into the three-phase inverter bridge control cycle to generate the PFC duty cycle adjustment amount and the SVPWM zero vector allocation amount.

[0053] Furthermore, the control sequence is determined by the sampling order of the starting boundary of the power supply side change segment and the starting boundary of the drive side change segment. When the starting boundary of the power supply side change segment comes first, a power supply side precedence mark is formed; when the starting boundary of the drive side change segment comes first, a drive side precedence mark is formed. This control sequence is not determined solely by the current value of voltage or current, but by the aforementioned relationship between the starting times of the power supply side change segment and the drive side change segment. Therefore, it is possible to distinguish between two situations: the bus power supply change occurs first and the motor load change occurs first.

[0054] In this embodiment, the PFC duty cycle adjustment direction corresponds to the rise and fall of the DC bus voltage, and the SVPWM zero vector movement direction corresponds to the increase and decrease of the torque current. For example, when the control sequence indicates that the power supply side is in advance and the DC bus voltage is decreasing, the PFC duty cycle adjustment direction can be written into the interleaved parallel Boost control cycle to make the PFC control correspond to the bus voltage change; when the control sequence indicates that the drive side is in advance and the torque current is increasing, the SVPWM zero vector movement direction can be written into the three-phase inverter bridge control cycle to make the vector distribution of the three-phase inverter bridge correspond to the motor torque demand.

[0055] It should be noted that the PFC duty cycle adjustment and the SVPWM zero vector allocation are written into different control cycles, but both are constrained by the same control sequence. The PFC duty cycle adjustment acts on the interleaved parallel Boost circuit, and the SVPWM zero vector allocation acts on the three-phase inverter bridge. This enables the power conversion side and the motor drive side to form corresponding control under the same sampling timing, rather than adjusting independently based on their local states.

[0056] Based on the control sequence and the rise / fall relationship of the DC bus voltage, the PFC duty cycle adjustment direction is determined, including: Read the power supply side precedence marker or drive side precedence marker in the control sequence, and read the rise and fall relationship of the DC bus voltage within the power supply side change segment; When the control sequence is marked with the power supply side first, the rise and fall of the DC bus voltage is mapped to the interleaved parallel Boost control cycle. When the control sequence is marked with the drive side first, the increase and decrease of the torque current in the change segment on the drive side is mapped to the interleaved parallel Boost control cycle. The PFC duty cycle adjustment direction is determined based on the corresponding results within the interleaved parallel Boost control cycle.

[0057] In this embodiment, the power supply side prior marker indicates that the change on the DC bus side occurs before the change on the motor drive side, and the drive side prior marker indicates that the change on the motor drive side occurs before the change on the DC bus side. The rise and fall relationship of the DC bus voltage within the power supply side change segment is used to characterize the direction of change of the bus power supply state, and the increase and decrease relationship of the torque current within the drive side change segment is used to characterize the direction of change of the motor load demand. Both participate in the determination of the PFC duty cycle adjustment direction under different prior relationships.

[0058] Furthermore, when the control sequence is marked with the power supply side first, the interleaved parallel Boost control cycle directly receives the rise and fall relationship of the DC bus voltage, so that the PFC duty cycle adjustment direction corresponds to the bus voltage change; when the control sequence is marked with the drive side first, the interleaved parallel Boost control cycle receives the increase and decrease relationship of the torque current within the drive side change segment, so that the PFC duty cycle adjustment direction corresponds to the change of motor torque demand. This treatment can avoid the PFC duty cycle adjustment still only based on the bus voltage for lagging adjustment when the drive side load has changed but the bus voltage has not yet formed a complete response.

[0059] It should be noted that determining the PFC duty cycle adjustment direction based on the corresponding results within the interleaved parallel Boost control cycle means retaining the control basis corresponding to whether the power supply side or the drive side takes precedence within the control cycle, and determining the increase or decrease direction of the PFC duty cycle adjustment accordingly. Thus, the PFC duty cycle adjustment direction is continuously connected with the aforementioned power supply drive timing relationship, DC bus voltage rise and fall relationship, and torque current increase and decrease relationship, providing a basis for the subsequent control coordination between the interleaved parallel Boost circuit and the three-phase inverter bridge.

[0060] Example 2

[0061] Please see Figure 2 As shown, based on the same inventive concept, this embodiment discloses an integrated control method for the power supply and motor drive of a cooking machine. For details not covered in this embodiment, please refer to the relevant sections of Embodiment 1. The method includes: S10: Acquire DC bus voltage, bus current, single resistor sampling value, three-phase inverter bridge switch status, rotor position, heat sink temperature and speed feedback data. Based on the SVPWM effective vector interval corresponding to the three-phase inverter bridge switch status, write the single resistor sampling value into the phase current channel to obtain the three-phase phase current. S20: Based on the rotor position, the coordinate transformation of the three-phase current is performed to obtain the torque current. Based on the DC bus voltage, bus current and torque current, the power supply side change segment is determined. S30: Determine the drive-side change segment based on torque current and speed feedback data, and overlap the power supply-side change segment with the drive-side change segment according to the sampling time to obtain the power supply drive timing relationship; S40: Based on the power drive timing relationship, DC bus voltage and torque current, it generates PFC duty cycle adjustment and SVPWM zero vector allocation, and generates PWM blocking cycle according to heat sink temperature, bus current and three-phase phase current.

[0062] The detailed description above, in conjunction with the accompanying drawings, describes examples but does not represent all examples that can be implemented or fall within the scope of the claims. The terms “example” and “exemplary” are used in this specification to mean “serving as an example, instance or illustration” and do not mean “superior to or better than other examples”.

[0063] Throughout this specification, the phrase "an embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the invention. Therefore, the use of these phrases may refer to more than one embodiment. Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0064] It should also be noted that these embodiments may be described as processes depicted as flowcharts, structural diagrams, or block diagrams. Although a flowchart may describe the operations as sequential processes, many of these operations can be performed in parallel or concurrently, and the order of these operations may be rearranged.

Claims

1. An integrated power supply and motor drive control system for a cooking machine, characterized in that, include: Current Reconstruction Module: Used to acquire DC bus voltage, bus current, single resistor sampling value, three-phase inverter bridge switch status, rotor position, heat sink temperature and speed feedback data. Based on the SVPWM effective vector interval corresponding to the three-phase inverter bridge switch status, the single resistor sampling value is written into the phase current channel to obtain the three-phase phase current. Power sensing module: used to perform coordinate transformation of three-phase current based on rotor position to obtain torque current, and to determine the power supply side change segment based on DC bus voltage, bus current and torque current; Drive fusion module: used to determine the drive-side change segment based on torque current and speed feedback data, and to overlap the power supply-side change segment with the drive-side change segment according to the sampling time to obtain the power supply drive timing relationship; Integrated control module: used to generate PFC duty cycle adjustment and SVPWM zero vector allocation based on power drive timing relationship, DC bus voltage and torque current, and generate PWM lockout cycle according to heat sink temperature, bus current and three-phase phase current.

2. The integrated power supply and motor drive control system for a cooking machine according to claim 1, characterized in that, Based on the effective vector interval of SVPWM corresponding to the switching states of the three-phase inverter bridge, the sampled value of a single resistor is written into the phase current channel to obtain the three-phase phase current, including: Read the upper and lower bridge arm conduction phases in the three-phase inverter bridge switch states, and read the start and end boundaries of the SVPWM effective vector interval to form a switch interval correspondence table; Match the conducting phase of the bridge arm in the switch interval correspondence table with the direction of the bus current to obtain the sampling channel correspondence table; The sampling channel correspondence table is consulted according to the sampling time of the single resistor sampling value, and the single resistor sampling value is written into the phase current channel recorded in the sampling channel correspondence table. The unwritten phase current channels are supplemented according to the constraint relationship that the phase currents already written into the channel and the total three-phase current is zero, so as to obtain the three-phase current.

3. The integrated power supply and motor drive control system for a stir-fry machine according to claim 2, characterized in that, Matching the conducting phases of the bridge arms in the switch interval correspondence table with the direction of the bus current yields the sampling channel correspondence table, including: Read the SVPWM effective vector interval where the sampling time is located in the table corresponding to the switching interval, and extract the upper bridge arm conduction phase and the lower bridge arm conduction phase corresponding to the SVPWM effective vector interval; Based on the direction of the bus current, mark the current inflow phase and the current outflow phase in the upper and lower bridge arm conducting phases, and assign the current inflow phase and the current outflow phase to the phase current channel respectively to form channel candidates. Based on the direction of the bus current within the effective vector interval of the SVPWM where the single resistor sampling value is located, the phase current channel corresponding to the single resistor sampling value is selected from the channel candidates to obtain the sampling channel correspondence table.

4. The integrated power supply and motor drive control system for a cooking machine according to claim 1, characterized in that, The power supply side variation segments are determined based on DC bus voltage, bus current, and torque current, including: The DC bus voltages are arranged according to the sampling time, and the voltage change segments are divided according to the rise and fall relationship between adjacent sampling points; Read the bus current direction switching position within the voltage change segment, and mark the voltage change segment containing the bus current direction switching position as the bus current response segment; The positions of torque current increase / decrease are filled back into the bus current response segment, and the segment boundary is truncated according to the sampling order of torque current increase / decrease position and bus current direction switching position to obtain the power supply side change segment.

5. The integrated power supply and motor drive control system for a cooking machine according to claim 4, characterized in that, Read the bus current direction switching position within the voltage change segment, and mark the voltage change segment containing the bus current direction switching position as the bus current response segment, including: Read the current direction of adjacent sampling points of the bus current within the voltage change segment, and mark the sampling points where the current direction changes as the bus current direction switching positions; The bus current direction switching position is backfilled into the corresponding voltage change segment according to the sampling time, and the voltage change segment containing the bus current direction switching position is retained. By extracting the DC bus voltage, bus current, and torque current from the start and end boundaries of the retained voltage change segment, the bus current response segment is obtained.

6. The integrated power supply and motor drive control system for a cooking machine according to claim 1, characterized in that, Based on torque current and speed feedback data, the drive-side variation segments are determined, including: The torque current is arranged according to the sampling time, and the torque current change segments are divided according to the increase or decrease relationship between adjacent sampling points; Read the response position of the speed feedback data within the torque current change segment, and mark the torque current change segment containing the response position of the speed feedback data as the speed response segment; The torque current increase / decrease relationship within the speed response segment is correlated with the response position of the speed feedback data according to the sampling time, and the segment boundary is truncated according to the corresponding sampling range to obtain the drive-side change segment.

7. The integrated power supply and motor drive control system for a stir-fry machine according to claim 6, characterized in that, The response position of the speed feedback data is read within the torque current change segment, and the torque current change segment containing the response position of the speed feedback data is marked as the speed response segment, including: Read the rise and fall relationship between adjacent sampling points of speed feedback data within the torque current change segment, and mark the sampling point where the rise and fall relationship switches as the response position of speed feedback data; The response position of the speed feedback data is backfilled into the corresponding torque current change segment according to the sampling time, and the torque current change segment containing the response position of the speed feedback data is retained. The torque current and speed feedback data are extracted according to the start and end boundaries of the retained torque current change segment to obtain the speed response segment.

8. The integrated power supply and motor drive control system for a stir-fry machine according to claim 1, characterized in that, Based on the power drive timing relationship, DC bus voltage, and torque current, PFC duty cycle regulation and SVPWM zero vector allocation are generated, including: Read the starting boundaries of the power supply side change segment and the starting boundaries of the drive side change segment in the power supply drive timing relationship, and determine the control sequence relationship based on the sampling order of the starting boundaries; The PFC duty cycle adjustment direction is determined based on the control sequence and the rise and fall of the DC bus voltage; the SVPWM zero vector movement direction is determined based on the control sequence and the increase and decrease of the torque current. Write the PFC duty cycle adjustment direction into the interleaved parallel Boost control cycle, and write the SVPWM zero vector movement direction into the three-phase inverter bridge control cycle to generate the PFC duty cycle adjustment amount and the SVPWM zero vector allocation amount.

9. The integrated power supply and motor drive control system for a cooking machine according to claim 8, characterized in that, Based on the control sequence and the rise / fall relationship of the DC bus voltage, the PFC duty cycle adjustment direction is determined, including: Read the power supply side precedence marker or drive side precedence marker in the control sequence, and read the rise and fall relationship of the DC bus voltage within the power supply side change segment; When the control sequence is marked with the power supply side first, the rise and fall of the DC bus voltage is mapped to the interleaved parallel Boost control cycle. When the control sequence is marked with the drive side first, the increase and decrease of the torque current in the change segment on the drive side is mapped to the interleaved parallel Boost control cycle. The PFC duty cycle adjustment direction is determined based on the corresponding results within the interleaved parallel Boost control cycle.

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