Motor real-time power detection method and device and motor equipment

Abstract

The invention discloses a motor real-time power detection method, a motor real-time power detection device and motor equipment, relates to the technical field of motor operation detection, and aims to solve the technical problem that the real-time power detection precision and the system cost are difficult to consider at the same time due to dependence on inaccurate internal voltage parameters or additional hardware sensors in the field of sensorless variable frequency driving. According to the method, three-phase and two-phase voltages which accurately reflect the voltage state of the motor end are reversely reconstructed by multiplexing inherent six paths of PWM signals, bus voltage and presumption angle of the motor end, the three-phase and two-phase voltages are fused with the sampling current to calculate the instantaneous power, and then the instantaneous power is filtered and smoothed by software, so that the reference precision and anti-interference performance of power calculation are fundamentally improved, and the power calculation efficiency is improved. Under the condition that no hardware cost is added, the detection precision and stability in a full power range (especially a high power working condition) are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of motor operation detection technology, specifically to a method, device, and motor equipment for real-time motor power detection. Background Technology

[0002] In sensorless variable frequency drive control systems, real-time power detection is crucial for ensuring stable motor output power and avoiding energy waste. Currently, there are two main existing technical solutions: one involves adding extra electronic components (such as resistors, capacitors, and transistors) to the hardware circuit to directly detect bus voltage and current to calculate real-time power. However, this method increases system cost and structural complexity, hindering cost reduction and efficiency improvement. The other method utilizes the two-phase voltages [Vd, Vq] and two-phase currents [Id, Iq] generated during variable frequency control to synthesize instantaneous power through coordinate transformation. However, since these two-phase voltage data originate from within the control algorithm, they fail to accurately reflect the dynamic characteristics of the actual motor terminal voltage. Especially under high-power conditions, the calculation error increases significantly with rising power, leading to decreased modulation accuracy of the control system, increased energy loss, and output power fluctuations, severely restricting the energy efficiency and stability of the motor drive. These inherent defects highlight the insufficient balance between accuracy and cost in existing technologies, necessitating an innovative method that requires no hardware modifications, is based on existing control parameters, and can accurately estimate real-time power.

[0003] The information disclosed in the background section is only intended to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to address the technical problem in the field of sensorless variable frequency drives where the accuracy of real-time power detection is difficult to balance with system cost due to reliance on inaccurate internal voltage parameters or additional hardware sensors. This invention proposes a method, device, and motor equipment for real-time power detection of motors. By reusing the inherent 6-channel PWM signals, bus voltage, and estimated advance angle at the motor terminals, it reverse-reconstructs three-phase and two-phase voltages that accurately reflect the voltage state at the motor terminals. These voltages are then fused with the sampled current to calculate instantaneous power, followed by software filtering and smoothing. This fundamentally improves the baseline accuracy and anti-interference capability of power calculation, achieving a significant improvement in detection accuracy and stability across the entire power range (especially in high-power conditions) without adding any hardware costs.

[0005] In a first aspect, one technical solution provided in the embodiments of the present invention is: a method for real-time power detection of a motor, comprising the following steps: Acquire multiple PWM signals, two-phase current values, advance angle data, and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process; The multi-channel PWM signals are combined with the bus voltage value to perform a voltage conversion to obtain the three-phase voltage value; The three-phase voltage values ​​are combined with the advance angle data to perform a secondary voltage conversion to obtain the target two-phase voltage values; The instantaneous power of the motor is determined by combining the target two-phase voltage value and the two-phase current value; The instantaneous power is filtered to obtain the real-time power value.

[0006] As a preferred embodiment, the multi-channel PWM signals are combined with the bus voltage value to perform a voltage conversion to obtain the three-phase voltage value, including the following steps: The PWM duty cycle of the corresponding three-phase winding of the motor is obtained based on the multi-channel PWM signals; the multi-channel PWM signals are six-channel multi-channel PWM signals; Multiply the PWM duty cycle of each phase by the corresponding bus voltage value to obtain the instantaneous voltage value of each phase in the three-phase stationary coordinate system; The three-phase voltage values ​​are determined by integrating the instantaneous values ​​of each phase voltage based on the phase correspondence of the three-phase windings of the motor.

[0007] As a preferred embodiment, the step of integrating the instantaneous values ​​of each phase voltage based on the phase correspondence of the three-phase windings of the motor to determine the three-phase voltage value includes the following steps: The instantaneous values ​​of each phase voltage are synthesized based on their spatial vector relationship in the three-phase stationary coordinate system to obtain the three-phase voltage vector; The three-phase voltage vector is used as the three-phase voltage value characterizing the voltage state of the motor terminals.

[0008] As a preferred embodiment, the three-phase voltage values ​​are combined with the advance angle data to perform a secondary voltage conversion to obtain the target two-phase voltage values, including the following steps: The three-phase voltage values ​​are converted into the first voltage component in a two-phase stationary coordinate system using Clarke transformation. The first voltage component is combined with the advance angle data and converted into a second voltage component in a two-phase rotating coordinate system using the Park transformation; the second voltage component is used as the target two-phase voltage value.

[0009] As a preferred embodiment, the step of converting the first voltage component into a second voltage component in a two-phase rotating coordinate system by combining the advance angle data with the Park transformation includes the following steps: Calculate the corresponding sine and cosine function values ​​based on the advance angle data; The first voltage component Axis voltage components and The d-axis voltage component and the q-axis voltage component of the second voltage component are obtained by linearly combining the sine function value and the cosine function value, respectively.

[0010] As a preferred embodiment, determining the instantaneous power of the motor operation by combining the target two-phase voltage value and the two-phase current value includes the following steps: Obtain the d-axis voltage component and q-axis voltage component of the target two-phase voltage value, as well as the d-axis current component and q-axis current component of the two-phase current value; Calculate the first product of the d-axis voltage component and the d-axis current component, and the second product of the q-axis voltage component and the q-axis current component; The instantaneous power of the motor is obtained by summing the first product and the second product.

[0011] As a preferred embodiment, the step of filtering the instantaneous power to obtain the real-time power value includes the following steps: Multiple instantaneous powers are collected as a sample sequence within a preset time window; The effective sample set is obtained by removing the maximum and minimum value samples from the sample sequence; The real-time power value is obtained by calculating the arithmetic mean of all sample values ​​in the effective sample set.

[0012] As a preferred embodiment, the steps for obtaining the advance angle data are as follows: After the motor enters the closed-loop control stage, the position angle of the motor rotor is calculated in real time in each control cycle using a vector frequency conversion algorithm; the position angle calculated in the previous control cycle is used as the advance angle data required for the current control cycle.

[0013] Secondly, one technical solution provided in this embodiment of the invention is: a real-time power detection device for a motor, comprising: The parameter acquisition module is used to acquire multiple PWM signals, two-phase current values, advance angle data, and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process. The voltage reconstruction module is connected to the parameter acquisition module and is used to reconstruct the three-phase voltage values ​​by performing coordinate transformation based on the multi-channel PWM signals and the bus voltage values. The coordinate transformation module, connected to the voltage reconstruction module and the parameter acquisition module, is used to transform the three-phase voltage values ​​and the advance angle data into a two-phase rotating coordinate system to obtain the target two-phase voltage values. A power calculation module, connected to the coordinate transformation module and the parameter acquisition module, is used to calculate the instantaneous power of the motor operation based on the target two-phase voltage value and the two-phase current value. A filtering module, connected to the power calculation module, is used to filter the instantaneous power and output a real-time power value. An execution module, connected to the filtering module, is used to perform motor power modulation based on the real-time power value.

[0014] Thirdly, one technical solution provided in the embodiments of the present invention is: a motor device, including a motor and a real-time power detection device for the motor connected to the motor.

[0015] The present invention has at least the following substantial beneficial effects: Based on an in-depth analysis of the technical content of the specification, the three most non-obvious substantive technical effects of this invention are derived and described below: (1) In response to the problem of increased power calculation error caused by distortion of internal voltage parameters under high power conditions, this application collects and utilizes the 6 original PWM signals of the drive stage, combined with the measured bus voltage, and reconstructs the three-phase voltage values ​​that can truly reflect the voltage state of the motor terminals in the three-phase stationary coordinate system through duty cycle mapping and coordinate transformation (Clarke transformation). This technical approach breaks away from the mindset of relying on inaccurate voltage parameters inside the control algorithm in the traditional scheme, and ensures the accuracy of the voltage reference from the signal source. Thus, the power calculation error will not increase significantly with the increase of power in the full power range, especially under high load conditions, and the systematic accuracy and reliability of power detection are significantly improved.

[0016] (2) In view of the problem that adding hardware sensors to improve accuracy increases the system cost and complexity, this application proposes to reuse all the inherent hardware resources of the sensorless frequency conversion control system and creatively integrate and coordinate the multi-source parameters such as PWM signal, bus voltage, advance angle and sampling current at the algorithm level. This technical means realizes the seamless embedding of power detection function on the existing hardware platform, and achieves the technical effect of meeting the requirements of high-precision detection and low cost without changing any hardware structure or adding any additional electronic components, fundamentally solving the traditional contradiction between accuracy and cost.

[0017] (3) In view of the problem that the instantaneous power data has large fluctuations and is easy to cause system instability when used directly for control, this application proposes a real-time power filtering optimization scheme for control stability. By setting a filtering processing module at the end of the power calculation process, a specific algorithm is adopted to collect instantaneous power samples within a preset time window, remove extreme values ​​and calculate the average value. This technique effectively filters out the power data spike interference introduced by PWM switching noise and current sampling fluctuations, and finally outputs a smooth and stable real-time power value, which provides a high-quality and high-reliability feedback signal for the upper-level control strategy (such as constant power control), thereby significantly enhancing the control accuracy and running stability of the entire motor drive system.

[0018] The above description of the invention is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0019] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. The drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0020] Figure 1 This is a flowchart of a real-time power detection method for a motor according to an embodiment of the present invention.

[0021] Figure 2 This is a structural block diagram of a real-time power detection device for a motor according to an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only one preferred embodiment of this invention and are only used to explain this invention. They do not limit the scope of protection of this invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0023] Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe the operations (or steps) as sequential processes, many of the operations (or steps) can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but it may also have additional steps not included in the figures; the process may correspond to a method, function, procedure, subroutine, subroutine, etc.

[0024] In the field of sensorless variable frequency motor control, as described in the background section, achieving high-precision real-time power detection has always faced a dilemma: if external voltage and current sensors are used, although the accuracy can be improved, the system cost and complexity will be significantly increased; if the two-phase voltage parameters (Vd, Vq) inside the control algorithm are used for calculation, the power calculation error will increase sharply, especially under high-speed and high-load conditions, because these parameters deviate from the actual voltage at the motor end. This cannot meet the requirements of precise control and energy saving.

[0025] Based on this, the first embodiment provided in this invention is: a method for real-time power detection of a motor, such as... Figure 1 As shown, it includes the following steps: Acquire multiple PWM signals, two-phase current values, advance angle data, and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process; Multiple PWM signals are combined with the bus voltage value to perform a single voltage conversion to obtain the three-phase voltage value; The target two-phase voltage values ​​are obtained by combining the three-phase voltage values ​​with the advance angle data and performing a secondary voltage conversion. The instantaneous power of the motor is determined by combining the target two-phase voltage and two-phase current values; The instantaneous power is filtered to obtain the real-time power value.

[0026] Understandably, this embodiment first acquires the system's inherent parameters, such as multiple PWM signals generated by the drive stage, bus voltage, two-phase current, and advance angle. Then, it dynamically reconstructs a three-phase voltage that accurately reflects the motor's terminal voltage state using the PWM duty cycle and bus voltage. Next, it combines the advance angle data with a coordinate transformation chain (Clarke-Park transformation) to accurately convert it into a target voltage in a two-phase coordinate system that rotates synchronously with the rotor's magnetic field. Subsequently, it performs instantaneous power calculation on this high-precision voltage and the synchronously acquired two-phase current. The calculation results are then filtered by removing extreme values ​​and averaging to suppress pulsation. This achieves improved voltage reference accuracy from the signal source without increasing any hardware costs, effectively overcoming the accuracy and cost contradictions caused by internal voltage parameter distortion or external sensors in traditional solutions. Finally, it outputs a stable and accurate real-time power value, providing a reliable data foundation for the high-efficiency and high-stability variable frequency control of the motor.

[0027] It should be noted that the steps for obtaining the advance angle data are as follows: After the motor enters the closed-loop control stage, the position angle of the motor rotor is calculated in real time using a vector frequency conversion algorithm in each control cycle; the position angle calculated in the previous control cycle is used as the advance angle data required for the current control cycle. By using the converged and stable angle value of the previous cycle, the advance angle data required for the Park transformation in the current cycle is ensured to be both sufficiently accurate and strictly synchronized with the PWM carrier cycle. This effectively avoids the problem of coordinate transformation asynchrony caused by real-time calculation delay, ensuring the accuracy of voltage reconstruction and power calculation and the stability of system control.

[0028] It should be noted that, in order to solve the problem of large power calculation errors caused by the reliance on the distorted Vd / Vq voltage parameters within the control algorithm in the existing technology, this embodiment also provides a preferred implementation method: obtaining the three-phase voltage values ​​by performing a single voltage conversion using multiple PWM signals combined with the bus voltage value. The specific means include the following steps: The PWM duty cycle of the corresponding three-phase winding of the motor is obtained based on multiple PWM signals; the multiple PWM signals are six-channel PWM signals. Multiply the PWM duty cycle of each phase by the corresponding bus voltage value to obtain the instantaneous voltage value of each phase in the three-phase stationary coordinate system; The instantaneous values ​​of each phase voltage are integrated based on the phase correspondence of the three-phase windings of the motor to determine the three-phase voltage values.

[0029] Understandably, this embodiment first analyzes the six PWM signals to obtain the accurate duty cycle of the corresponding three-phase windings (for example, by detecting the PWM pulse width of the upper and lower bridge arms of each phase and calculating its effective duty cycle). Then, the duty cycle of each phase is multiplied in real time with the measured bus voltage value to directly calculate the instantaneous voltage value of each phase winding in the three-phase stationary coordinate system (ABC coordinate system). (It should be noted that this process essentially simulates the chopping output effect of the inverter bridge arm's power switching action on the DC bus voltage.) Finally, based on the phase correspondence of the three-phase windings with a spatial difference of 120° electrical angle, the above three phase voltage instantaneous values ​​are vector-integrated (for example, through Clarke transformation or its equivalent calculation) to obtain a three-phase voltage vector that can accurately represent the voltage applied to the motor terminals. This realizes the direct and distortion-free restoration of the actual voltage borne by the motor from the source of the drive signal (i.e., the PWM wave), providing a high-precision voltage reference for subsequent power calculations and fundamentally avoiding systematic calculation errors introduced by inaccurate voltage parameters in the internal algorithm.

[0030] It should be noted that, in order to address the problem that the instantaneous voltage values ​​of each phase obtained directly from the PWM duty cycle are still scattered and cannot fully represent the true voltage waveform characteristics at the motor terminals, this embodiment also provides a preferred implementation method: integrating the instantaneous voltage values ​​of each phase according to the phase correspondence of the three-phase windings of the motor to determine the three-phase voltage values. The specific means include the following steps: The three-phase voltage vector is obtained by synthesizing the instantaneous values ​​of each phase voltage based on their spatial vector relationship in the three-phase stationary coordinate system; The three-phase voltage vector is used as the three-phase voltage value to characterize the voltage state of the motor terminals.

[0031] It is understood that this embodiment performs vector synthesis of the separately calculated instantaneous three-phase voltage values ​​(such as Ua, Ub, and Uc) based on their spatial phase relationship of 120° electrical angle difference in the three-phase stationary coordinate system (for example, mapping them to two-phase stationary coordinates through Clarke transformation). - The coordinate system forms a unified voltage space vector Us, thereby integrating three independent scalar voltage values ​​into a comprehensive vector (i.e., a three-phase voltage vector) that can fully reflect the amplitude, frequency, and phase information of the motor terminal voltage. This realizes the transformation of discrete phase voltage information into a voltage vector that can accurately describe the state of the synthetic magnetic field inside the motor, avoiding the random errors that may be caused by relying solely on a single phase voltage for subsequent calculations.

[0032] It should be noted that, in order to solve the problem of instantaneous fluctuations in power calculation caused by the asynchrony between the voltage signal obtained from the three-phase stationary coordinate system and the motor rotor magnetic field, this embodiment also provides a preferred implementation method: the three-phase voltage values ​​are combined with the advance angle data to perform a secondary voltage conversion to obtain the target two-phase voltage values, including the following steps: The three-phase voltage values ​​are converted into the first voltage component in a two-phase stationary coordinate system using Clarke transformation. The first voltage component is combined with the advance angle data and converted into a second voltage component in a two-phase rotating coordinate system using the Park transformation; the second voltage component is then used as the target two-phase voltage value.

[0033] Understandably, in this embodiment, the reconstructed three-phase voltage values ​​are first converted into a two-phase stationary coordinate system using Clarke transformation. - The first voltage component in the coordinate system simplifies the conversion from a three-phase system to a two-phase system (e.g., converting three-phase voltages Ua, Ub, and Uc, which are 120° out of phase, into spatially orthogonal voltage components). and Then, the first voltage component is combined with the advance angle data characterizing the real-time position of the rotor magnetic field and rotated through the Park transform to a two-phase rotating coordinate system (dq coordinate system) synchronized with the rotor to obtain the second voltage component as the target two-phase voltage value (e.g., using the advance angle θ to...). and By performing coordinate rotation calculations, the direct-axis voltage Vd and quadrature-axis voltage Vq are finally output. This converts the voltage signal from a stationary reference frame to a reference frame that rotates synchronously with the rotor magnetic field. This allows the target voltage component to be directly calculated for power in the same coordinate system as the synchronously acquired two-phase current components (Id, Iq). This effectively eliminates the interference of voltage and current phase difference caused by motor rotation on instantaneous power calculation, thereby significantly improving the accuracy and stability of power detection.

[0034] It should be noted that, to address the issue of pulsations in instantaneous power calculation caused by the relative motion between the voltage component and the rotor magnetic field in the two-phase stationary coordinate system, this embodiment also provides a preferred implementation method: converting the first voltage component, combined with the advance angle data, into a second voltage component in the two-phase rotating coordinate system using Park transformation; the specific methods include the following steps: Calculate the corresponding sine and cosine function values ​​based on the advance angle data; The first voltage component Axis voltage components and The d-axis voltage component and q-axis voltage component of the second voltage component are obtained by linearly combining the sine function value and the cosine function value, respectively.

[0035] It is understandable that this embodiment first calculates the corresponding sine value based on the advance angle data estimated in real time using the vector frequency conversion algorithm. ) and cosine value ( ), and then the first voltage component Axis voltage component ( )and Axis voltage component ( ) and perform specific linear combination operations with these trigonometric function values ​​(for example, according to the Park transform formula: direct-axis voltage Vd = × + × Cross-axis voltage Vq = - × + × This decouples the second voltage component (Vd, Vq) that characterizes the excitation and torque components in the rotor synchronous rotating coordinate system, and realizes the precise rotation of the voltage vector from the stationary frame to a dynamic reference system that is completely aligned with the rotor magnetic field, so that the voltage signal and the current signal are completely synchronized in a physical sense, eliminating the relative phase difference between them.

[0036] It should be noted that, in order to achieve accurate instantaneous power calculation that matches the rotor field-oriented control, and to overcome the power pulsation problem caused by the asynchrony of voltage and current phases in the stationary coordinate system in traditional methods, this embodiment further provides an optional embodiment: determining the instantaneous power of the motor operation by combining the target two-phase voltage value and the two-phase current value, specifically including the following steps: Obtain the d-axis voltage components and q-axis voltage components of the target two-phase voltage values, as well as the d-axis current components and q-axis current components of the two-phase current values; Calculate the first product of the d-axis voltage component and the d-axis current component, and the second product of the q-axis voltage component and the q-axis current component; The instantaneous power of the motor is obtained by summing the first product and the second product.

[0037] Understandably, this embodiment first obtains the target two-phase voltage components (Vd, Vq) and two-phase current components (Id, Iq) that are completely aligned with the rotor magnetic field after coordinate transformation. Then, in the completely decoupled dq axis system, the product of Vd and Id (first product) representing excitation power and the product of Vq and Iq (second product) representing torque power are calculated respectively. Finally, the two orthogonal power components are algebraically summed, realizing the establishment of a power calculation model that completely corresponds to the physical process of electromagnetic energy conversion of the motor in the synchronous rotating coordinate system. This fundamentally eliminates the power calculation pulsation caused by the phase difference between voltage and current, so that the instantaneous power calculation result can accurately reflect the real-time active power of the motor.

[0038] It should be noted that, in order to solve the power pulsation problem caused by PWM switching noise and current sampling fluctuations in the instantaneous power calculation results and to ensure the stability and reliability of the output power value, this embodiment further provides an optional embodiment: filtering the instantaneous power to obtain the real-time power value, specifically including the following steps: Multiple instantaneous power samples were collected within a preset time window as a sample sequence; The effective sample set is obtained by removing the maximum and minimum value samples from the sample sequence; The real-time power value is obtained by averaging the arithmetic mean of all sample values ​​in the effective sample set.

[0039] Understandably, this embodiment first collects multiple instantaneous power calculation results within a preset time window (such as 10 consecutive control cycles) to form a sample sequence. First, the maximum and minimum value samples in the sequence are removed to eliminate abnormal pulse interference. Then, the arithmetic mean of all power values ​​in the remaining valid sample set is calculated. This achieves the goal of effectively filtering out the influence of random interference and occasional pulses on the power data while preserving the true power change trend. As a result, the final output real-time power value can not only respond quickly to actual power changes, but also has excellent smoothness and stability. This provides a reliable and jitter-free feedback signal for the power regulation module of the motor control system, thereby significantly improving the accuracy of power control and the stability of system operation.

[0040] Another embodiment of the present invention provides: a real-time power detection device for a motor, such as... Figure 2 As shown, it includes: The parameter acquisition module 101 is used to acquire the multi-channel PWM signals, two-phase current values, advance angle data and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process. The voltage reconstruction module 102 is connected to the parameter acquisition module and is used to reconstruct the three-phase voltage values ​​based on the coordinate transformation of multiple PWM signals and the bus voltage value. The coordinate transformation module 103 is connected to the voltage reconstruction module and the parameter acquisition module. It is used to transform the three-phase voltage values ​​and advance angle data into a two-phase rotating coordinate system to obtain the target two-phase voltage values. The power calculation module 104 is connected to the coordinate transformation module and the parameter acquisition module, and is used to calculate the instantaneous power of the motor operation based on the target two-phase voltage value and two-phase current value. The filtering module 105 is connected to the power calculation module and is used to filter the instantaneous power and output the real-time power value. The execution module 106 is connected to the filtering module and is used to perform motor power modulation based on the real-time power value.

[0041] Understandably, in this embodiment, the parameter acquisition module directly connects to the microcontroller's timer unit and ADC sampling unit to capture in real time the duty cycle data of six PWM signals, the raw values ​​of two-phase currents sampled by the current sensor, the rotor position angle calculated by the vector frequency conversion algorithm (whose principle is: without relying on position sensors, using real-time acquired motor phase currents and PWM voltages and other electrical parameters, continuously estimating the rotor flux position and speed through a state observer (such as a sliding mode observer, Romberg observer, etc.) or a model reference adaptive system) as the advance angle data, and the bus voltage value acquired through the voltage divider circuit; after receiving these parameters, the voltage reconstruction module first multiplies the PWM duty cycle of each phase with the bus voltage to obtain the instantaneous values ​​of the three-phase voltages, and then synthesizes them into a three-phase voltage vector through Clarke transformation; coordinates The transformation module then converts the three-phase voltage values ​​into target two-phase voltage values ​​in the dq coordinate system using the Clarke-Park transformation chain and the advance angle data. The power calculation module performs scalar multiplication and accumulation on the target voltage value and the corresponding current value to output the instantaneous power. The filtering module uses extreme value elimination and moving average algorithms to smooth the instantaneous power. Finally, the execution module feeds back the filtered real-time power value to the motor control core, dynamically adjusting the PWM output to achieve precise power modulation. This achieves a high degree of integration and collaborative work of each functional module on a single hardware platform. Through a systematic signal processing flow, the dispersed inherent parameters in the control system are transformed into high-precision power feedback signals. While ensuring detection accuracy, this completely avoids hardware modification costs and provides a stable and reliable power closed-loop control foundation for motor power modulation.

[0042] It should be noted that the multiple PWM signals are directly generated by the timer / counter unit inside the microcontroller (MCU). By configuring its compare / capture register, six PWM waveforms with phase differences are generated. The parameter acquisition module obtains the duty cycle information of each phase PWM in real time by reading the register status of the timer unit. The two-phase current values ​​are acquired by current sensing elements (such as high-precision sampling resistors or Hall current sensors) connected in the motor drive circuit. The generated analog voltage signals are converted into digital quantities by analog-to-digital converters (ADCs) and then read and stored by the parameter acquisition module. The advance angle data is calculated in real time by a sensorless position estimation algorithm (such as a sliding mode observer) running in the MCU in each control cycle. The parameter acquisition module directly obtains the data by accessing a specific memory address or register that stores the calculation results. The bus voltage value is sampled by a voltage divider resistor network connected between the positive and negative terminals of the DC bus. The attenuated voltage signal is also converted by the ADC and then read periodically by the parameter acquisition module.

[0043] It's important to note that the microcontroller (MCU) serves as the core hardware platform shared by the entire device. Its resources are shared by all the aforementioned functional modules, rather than belonging solely to any one specific module. Specifically: The parameter acquisition module uses the MCU's timer unit to generate and capture PWM signals, uses the ADC unit to sample current and bus voltage, and uses the CPU core to read the advance angle data calculated by the algorithm from memory or registers. The voltage reconstruction module, coordinate transformation module, power calculation module, and filtering module are essentially a series of algorithm programs running on the MCU's CPU core, relying on its computational capabilities for execution. The execution module ultimately reconfigures the PWM output through the MCU's timer unit to achieve power modulation.

[0044] Another embodiment of the present invention is a motor device, including a motor and a real-time power detection device connected to the motor.

[0045] It is understandable that the motor, as the controlled object and actuator, generates physical quantities such as actual current and back electromotive force in the drive circuit during its operation. These are converted into electrical signals through built-in sensors (such as current sampling resistors) and drive circuits (such as inverter bridges). At the same time, the motor real-time power detection device, as the core processing unit, continuously collects these signals, as well as the PWM wave and advance angle data generated by the controller, through the parameter acquisition module, forming a complete data stream from the physical execution end to the signal processing end.

[0046] Furthermore, the algorithm modules (voltage reconstruction module, coordinate transformation module, power calculation module, and filtering module) in the detection device process the collected raw data and finally output a high-precision, smooth real-time power value; this power value is fed back to the variable frequency drive control system of the motor in real time through the execution module, forming a closed-loop feedback.

[0047] Furthermore, the motor drive system (with the aforementioned MCU as its core) dynamically adjusts the PWM output strategy (such as adjusting the duty cycle and frequency) based on the received precise real-time power value, thereby achieving precise control of the motor torque and speed. This enables the motor to: quickly maintain constant power output during load fluctuations, avoiding overload or insufficient power; optimize energy consumption according to actual power requirements, avoiding energy waste; maintain high control precision throughout the entire operating range; and significantly improve system stability, especially under high-speed and high-load conditions.

[0048] Through the aforementioned collaborative working mode, this motor equipment achieves end-to-end optimization from signal sensing and data processing to power control without increasing hardware costs, ultimately achieving the unification of high-precision power detection and high-efficiency motor control.

[0049] The specific embodiments described above are preferred embodiments of the real-time power detection method, device and motor equipment of the present invention, and are not intended to limit the specific scope of the present invention. The scope of the present invention includes but is not limited to the specific embodiments described above. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A method for real-time power detection of a motor, characterized in that: Includes the following steps: Acquire multiple PWM signals, two-phase current values, advance angle data, and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process; The multi-channel PWM signals are combined with the bus voltage value to perform a voltage conversion to obtain the three-phase voltage value; The three-phase voltage values ​​are combined with the advance angle data to perform a secondary voltage conversion to obtain the target two-phase voltage values; The instantaneous power of the motor is determined by combining the target two-phase voltage value and the two-phase current value; The instantaneous power is filtered to obtain the real-time power value.

2. The method for real-time power detection of a motor according to claim 1, characterized in that: The multi-channel PWM signals are combined with the bus voltage value to perform a voltage conversion to obtain the three-phase voltage value, including the following steps: The PWM duty cycle of the corresponding three-phase winding of the motor is obtained based on the multi-channel PWM signals; the multi-channel PWM signals are six-channel multi-channel PWM signals; Multiply the PWM duty cycle of each phase by the corresponding bus voltage value to obtain the instantaneous voltage value of each phase in the three-phase stationary coordinate system; The three-phase voltage values ​​are determined by integrating the instantaneous values ​​of each phase voltage based on the phase correspondence of the three-phase windings of the motor.

3. The method for real-time power detection of a motor according to claim 2, characterized in that: The process of integrating the instantaneous values ​​of each phase voltage based on the phase correspondence of the three-phase windings of the motor to determine the three-phase voltage value includes the following steps: The instantaneous values ​​of each phase voltage are synthesized based on their spatial vector relationship in the three-phase stationary coordinate system to obtain the three-phase voltage vector; The three-phase voltage vector is used as the three-phase voltage value characterizing the voltage state of the motor terminals.

4. A method for real-time power detection of a motor according to claim 1, 2, or 3, characterized in that: The three-phase voltage values ​​are combined with the advance angle data to perform a secondary voltage conversion to obtain the target two-phase voltage values, including the following steps: The three-phase voltage values ​​are converted into the first voltage component in a two-phase stationary coordinate system using Clarke transformation. The first voltage component is combined with the advance angle data and converted into a second voltage component in a two-phase rotating coordinate system using the Park transformation. The second voltage component is used as the target two-phase voltage value.

5. The method for real-time power detection of a motor according to claim 4, characterized in that: The step of converting the first voltage component, combined with the advance angle data, into a second voltage component in a two-phase rotating coordinate system via Park transformation includes the following steps: Calculate the corresponding sine and cosine function values ​​based on the advance angle data; The α-axis and β-axis voltage components of the first voltage component are linearly combined with the sine and cosine function values, respectively, to calculate the d-axis and q-axis voltage components of the second voltage component.

6. A method for real-time power detection of a motor according to claim 1 or 5, characterized in that: Determining the instantaneous power of the motor by combining the target two-phase voltage value and the two-phase current value includes the following steps: Obtain the d-axis voltage component and q-axis voltage component of the target two-phase voltage value, as well as the d-axis current component and q-axis current component of the two-phase current value; Calculate the first product of the d-axis voltage component and the d-axis current component, and the second product of the q-axis voltage component and the q-axis current component; The instantaneous power of the motor is obtained by summing the first product and the second product.

7. The method for real-time power detection of a motor according to claim 1, characterized in that: The step of filtering the instantaneous power to obtain the real-time power value includes the following steps: Multiple instantaneous powers are collected as a sample sequence within a preset time window; The effective sample set is obtained by removing the maximum and minimum value samples from the sample sequence; The real-time power value is obtained by calculating the arithmetic mean of all sample values ​​in the effective sample set.

8. A method for real-time power detection of a motor according to claim 1 or 5, characterized in that: The steps for obtaining the advance angle data are as follows: After the motor enters the closed-loop control stage, the position angle of the motor rotor is calculated in real time in each control cycle using a vector frequency conversion algorithm; the position angle calculated in the previous control cycle is used as the advance angle data required for the current control cycle.

9. A real-time power detection device for a motor, characterized in that: include: The parameter acquisition module is used to acquire multiple PWM signals, two-phase current values, advance angle data, and bus voltage values ​​generated by the motor during the sensorless variable frequency drive control process. The voltage reconstruction module is connected to the parameter acquisition module and is used to reconstruct the three-phase voltage values ​​by performing coordinate transformation based on the multi-channel PWM signals and the bus voltage values. The coordinate transformation module, connected to the voltage reconstruction module and the parameter acquisition module, is used to transform the three-phase voltage values ​​and the advance angle data into a two-phase rotating coordinate system to obtain the target two-phase voltage values. A power calculation module, connected to the coordinate transformation module and the parameter acquisition module, is used to calculate the instantaneous power of the motor operation based on the target two-phase voltage value and the two-phase current value. A filtering module, connected to the power calculation module, is used to filter the instantaneous power and output a real-time power value. An execution module, connected to the filtering module, is used to perform motor power modulation based on the real-time power value.

10. A motor device, characterized in that: It includes a motor and a motor real-time power detection device as described in claim 9 connected to the motor.

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