阅读说明：本技术 一种可联网的开关磁阻电机控制方法 (Networking switched reluctance motor control method ) 是由 穆浩伟 苏杭 *** 于 2019-10-30 设计创作，主要内容包括：本发明公开了一种可联网的开关磁阻电机控制方法，客户端通过通信网络装置与指定洗衣机ID，建立与该洗衣机的连接；洗衣机的控制器通过位置检测装置和电流检测模块收集电机转子的位置信号和电流信号；控制器根据位置信号计算洗衣机电机当前状态，包括电机转速和转向，按照通讯协议将洗衣机当前状态发送给客户端；控制器根据采样的位置信号和电流信号，基于模型预测的方法控制电机功率变换器中开关管的导通，实现电机运行。本发明更加符合现代化生活的要求，可实现远程监控；具有运行效率较高、调速范围大、静音运行、成本较低的优势。(The invention discloses a method for controlling a switched reluctance motor capable of being networked, wherein a client establishes connection with a specified washing machine ID through a communication network device; a controller of the washing machine collects a position signal and a current signal of a motor rotor through a position detection device and a current detection module; the controller calculates the current state of the motor of the washing machine according to the position signal, including the rotating speed and the rotating direction of the motor, and sends the current state of the washing machine to the client according to a communication protocol; and the controller controls the conduction of a switching tube in the motor power converter based on a model prediction method according to the sampled position signal and the sampled current signal so as to realize the operation of the motor. The invention better meets the requirements of modern life and can realize remote monitoring; the speed-regulating device has the advantages of high operation efficiency, wide speed-regulating range, silent operation and low cost.)

1. A method for controlling a switched reluctance motor capable of being networked is characterized by comprising the following steps:

step 1, a client establishes connection with a specified washing machine ID through a communication network device;

step 2, a controller of the washing machine collects position signals and current signals of a motor rotor through a position detection device and a current detection module;

step 3, the controller calculates the current state of the motor of the washing machine according to the position signal, wherein the current state comprises the rotating speed and the rotating direction of the motor, and the current state of the washing machine is sent to the client according to a communication protocol;

and 4, controlling the conduction of a switching tube in the motor power converter by the controller according to the sampled position signal and current signal based on a model prediction method to realize the operation of the motor.

2. The method as claimed in claim 1, wherein the position detecting device comprises three photo sensors P1, P2 and P3, the three photo sensors are installed on the motor casing and are sequentially spaced at 120 °, and the positive and negative rotation of the motor can be determined according to the high and low points obtained by the photo sensors.

3. The method of claim 1, wherein the current detection module employs a hall element to feed back the magnitude of the current in the motor winding to the controller.

4. The method of claim 1, wherein in step 3, the protocol for information transmission between the client and the controller is modbus communication protocol.

5. The method as claimed in claim 1, wherein in step 3, the rotation speed and the rotation direction information are transmitted in a separate transmission mode or a combined transmission mode through a function code bit flag in the transmission information.

6. The method of claim 1, wherein the power converter comprises six switching tubes a1, a2, B1, B2, C1, C2 in the form of asymmetric half bridge circuits.

7. The method for controlling the switched reluctance motor capable of being networked according to claim 1, wherein the specific steps of the switch tube conduction control are as follows:

step 4.1, judging the position information of the rotor according to the codes of the position signals collected by the position measuring device;

step 4.2, acquiring the current i at the moment k of the corresponding phase according to the position of the rotor_kCalculating the flux linkage value psi of the motor at the phase angles of 22.5 deg., 17.5 deg., 12.5 deg. and 0 deg. by using the coincidence of the central lines of salient poles of stator pole and rotor pole as initial positions_max、ψ_p、ψ_r、ψ_min：

Step 4.3, obtaining psi according to the calculation_max、ψ_p、ψ_r、ψ_minCalculating the DC component psi of the motor flux linkage₀First order component psi₁Second order component psi₂Third order component psi₃：

Step 4.4, according to the calculated direct current component psi₀First order component psi₁Second order component psi₂Third order component psi₃Number of poles N with the motor rotor_rAnd calculating the motor flux linkage psi:

ψ(i,θ_k)＝ψ₀(i)+ψ₁(i)*cos(N_rθ)+ψ₂(i)*cos(2N_rθ_k)+ψ₃(i)*cos(3N_rθ_k)

wherein, theta_kThe phase angle of the rotor at the moment k is calculated by an EQep module of the position measuring device according to the position signal code;

step 4.5, according to the phase angle theta_kCalculating the angular velocity omega of the motor, and combining the motor phase current i at the moment k_kMotor flux linkage psi at time k, time difference delta T between time k +1 and time k, and motor winding resistance R, k +1 at time kRated voltage U of motor_k+1Predicting the motor phase current i at the moment k +1_k+1：

Step 4.6, according to the phase angle theta of the rotor at the moment k_kCalculating the phase angle theta at the time k +1_k+1：

θ_k+1＝θ_k+ωΔT

Step 4.7, according to the predicted k +1 time phase angle theta_k+1Motor phase current i at time k +1_k+1And predicting the torque T at the moment k +1 by fitting a function f to the motor torque obtained by off-line static testing_k+1：

T_k+1＝f(i_k+1,θ_k+1)

Step 4.8, setting the rotating speed n according to the motor_rAnd the actual speed n_cCalculating the reference torque T by the Pi element_refVariable u before truncation_presat：

In the formula K_pIs a proportionality coefficient, K_iIs the integral coefficient, K_cIs a differential gain factor;

step 4.9, p u_presatPerforming truncation calculation to obtain reference torque T_ref：

In the formula T_maxFor the upper limit of torque obtained from the motor characteristics, T_minA lower torque limit obtained according to the motor characteristics;

step 4.10, reference torque T according to time k_refActual torque T at time k +1_realEstablishing a metric T_refAnd T_realObjective function of gap J:

J＝(T_real-T_ref(k))²

step 4.11, actual Torque T due to time k +1_realNot available at time k, from T_k+1As T_realThen the target function pair T is obtained_realIf the gradient is larger than 0, the switch tube of the corresponding phase of the rotor is switched off, and if the gradient is smaller than 0, the switch tube of the corresponding phase is switched on, so that the optimal control of the switched reluctance motor is finally realized.

Technical Field

The invention relates to a switched reluctance motor speed regulation and equipment networking technology, in particular to a networking control technology of a switched reluctance motor based on model prediction.

Background

In modern society, people are more and more aware of clothes washing feeling caused by difference of clothes texture, and washing machines are also more and more used for washing clothes. The current motors used in washing machines are mainly single-phase double-speed asynchronous motors, unidirectional series excitation motors, variable frequency induction motors and the like operated by capacitors, and have the defects of low efficiency, small speed regulation range, large noise, short service life and the like. For a driving motor in a washing machine, the motor has poor working conditions and requires that the driving motor meets the requirement of low speed during washing, the maximum rotating speed in the dehydration process is large enough, and different rotating speed schemes are possibly needed to perform washing and dehydration when different clothes are faced. Therefore, the capacitor-run single-phase double-speed asynchronous motor, the unidirectional series motor and the variable frequency induction motor are not suitable for being used in the washing machine.

The switched reluctance motor has larger torque and smaller current when being started, so that the switched reluctance motor can be well adapted to the running mode of frequent forward and reverse rotation switching in the washing process. Meanwhile, the speed regulation range of the switched reluctance motor is large, and the requirements of low rotating speed during washing and high rotating speed of the roller during dehydration can be met simultaneously; the switch reluctance motor has the characteristic of good speed regulation performance, so that the washing machine can be washed more cleanly. Therefore, the switched reluctance motor is gradually used in washing laundry. However, the switched reluctance motor has a problem of large torque ripple and large noise. And the traditional control method can only be locally controlled and cannot play the excellent characteristics of the switched reluctance motor in the washing process.

Disclosure of Invention

The invention aims to provide a networked control method of a switched reluctance motor.

The technical solution for realizing the purpose of the invention is as follows: a method for controlling a switched reluctance motor capable of being networked comprises the following steps:

step 1, a client establishes connection with a specified washing machine ID through a communication network device;

step 2, a controller of the washing machine collects position signals and current signals of a motor rotor through a position detection device and a current detection module;

step 3, the controller calculates the current state of the motor of the washing machine according to the position signal, wherein the current state comprises the rotating speed and the rotating direction of the motor, and the current state of the washing machine is sent to the client according to a communication protocol;

and 4, controlling the conduction of a switching tube in the motor power converter by the controller according to the sampled position signal and current signal based on a model prediction method to realize the operation of the motor.

Compared with the prior art, the invention has the following remarkable advantages: 1) the invention better meets the requirements of modern life and can realize remote monitoring; 2) the invention has the advantages of higher operation efficiency, large speed regulation range, silent operation and lower cost.

Drawings

Fig. 1 is a flow chart of a network-enabled switched reluctance motor control method of the present invention.

Fig. 2 is a block diagram of a network-enabled switched reluctance motor control method of the present invention.

Fig. 3 is a structural view of the position detecting apparatus of the present invention.

Fig. 4 is a wiring diagram of a power switch tube in the control system of the present invention.

Detailed Description

As shown in fig. 1-2, the network-enabled switched reluctance motor control method includes the steps of:

step 1, a client establishes connection with a specified washing machine ID through a communication network device;

step 2, a controller of the washing machine collects position signals and current signals of a motor rotor through a position detection device and a current detection module;

the position detection device comprises three photoelectric sensors P1, P2 and P3, wherein the three photoelectric sensors are arranged on the motor shell and are sequentially arranged at intervals of 120 degrees, and the position detection device is specifically shown in figure 3. The positive machine rotation and the negative machine rotation can be judged according to the high-low point obtained by the photoelectric sensor. Taking an 6/4-pole switched reluctance motor as an example, position signals in the operation process of the motor have six codes of code 0 ("101"), code 1 ("100"), code 2 ("110"), code 3 ("010"), code 4 ("011"), and code 5 ("001"). The motor can be judged to be in forward rotation or reverse rotation according to the six codes. The occurrence of the position signal in the order of code 0, code 2,. code 5, code 0 is a positive rotation, and vice versa. The current detection module adopts a Hall element and feeds the current in the motor winding back to the controller.

Step 3, the controller calculates the current state of the motor of the washing machine according to the position signal, wherein the current state comprises the rotating speed and the rotating direction of the motor, and the current state of the washing machine is sent to the client according to a communication protocol;

the protocol for information transmission between the client and the controller is modbus communication protocol. The rotating speed and the steering information can be sent separately or can be sent in one time in a combined mode and content through a function code bit mark in the transmission information.

Step 4, the controller controls the conduction of the switch tube by adopting a model prediction-based method according to the sampled position signal and the sampled current signal, so that the motor runs with low pulsation and low noise on the premise of keeping the advantages of the switched reluctance motor;

in the power converter, the power switch tube adopts an asymmetric half-bridge circuit, as shown in fig. 4, A1 and A2 are connected with a phase A winding of the motor; b1 and B2 are connected with a phase B winding of the motor; c1 and C2 are connected with the C-phase winding of the motor. The switching tube control specifically comprises the following substeps:

and 4.1, judging the position information of the rotor according to the codes of the position signals collected by the position measuring device, taking an 6/4-pole switched reluctance motor as an example, the signals at the position of the rotor corresponding to the position A are coded into '010' or '110', the signals at the position B corresponding to the position B are coded into '001' and '011', and the signals at the position C corresponding to the position C are coded into '100' and '101'.

Step 4.2, acquiring the current i at the moment k of the corresponding phase according to the position of the rotor_kCalculating the flux linkage value psi of the motor at the phase angles of 22.5 deg., 17.5 deg., 12.5 deg. and 0 deg. by using the coincidence of the central lines of salient poles of stator pole and rotor pole as initial positions_max、ψ_p、ψ_r、ψ_min：

Step 4.3, obtaining psi according to the calculation_max、ψ_p、ψ_r、ψ_minCalculating the DC component psi of the motor flux linkage₀First order component psi₁Second order component psi₂Third order component psi₃：

Step 4.4, according to the calculated direct current component psi₀First order component psi₁Second order component psi₂Third order component psi₃Number of poles N with the motor rotor_rAnd calculating the motor flux linkage psi:

ψ(i,θ_k)＝ψ₀(i)+ψ₁(i)*cos(N_rθ)+ψ₂(i)*cos(2N_rθ_k)+ψ₃(i)*cos(3N_rθ_k)

wherein, theta_kThe phase angle of the rotor at the moment k is calculated by an EQep module of the position measuring device according to the position signal code;

step 4.5, according to the phase angle theta_kCalculating the angular velocity omega of the motor, and combining the motor phase current i at the moment k_kMotor flux linkage psi at moment k, time difference delta T between moment k +1 and moment k, and motor rated voltage U at moment R, k +1_k+1Predicting the motor phase current i at the moment k +1_k+1：

Step 4.6, according to the phase angle theta of the rotor at the moment k_kCalculating the phase angle theta at the time k +1_k+1：

θ_k+1＝θ_k+ωΔT

Step 4.7, according to the predicted k +1 time phase angle theta_k+1Motor phase current i at time k +1_k+1And predicting the torque T at the moment k +1 by fitting a function f to the motor torque obtained by off-line static testing_k+1：

T_k+1＝f(i_k+1,θ_k+1)

Step 4.8, setting the rotating speed n according to the motor_rAnd the actual speed n_cReference is calculated by the Pi elementTorque T_refVariable u before truncation_presat：

In the formula K_pIs a proportionality coefficient, K_iIs the product coefficient, K_cIs the differential gain;

step 4.9, p u_presatPerforming truncation calculation to obtain reference torque T_ref：

In the formula T_maxFor the upper limit of torque obtained from the motor characteristics, T_minA lower torque limit obtained according to the motor characteristics;

step 4.10, reference torque T according to time k_refActual torque T at time k +1_realEstablishing a metric T_refAnd T_realObjective function of gap J:

J＝(T_real-T_ref(k))²

step 4.11, actual Torque T due to time k +1_realNot available at time k, from T_k+1As T_realThen the target function pair T is obtained_realIf the gradient is larger than 0, the switch tube of the corresponding phase of the rotor is switched off, and if the gradient is smaller than 0, the switch tube of the corresponding phase is switched on, so that the optimal control of the switched reluctance motor is finally realized, and the washing machine motor has the advantages of excellent speed regulation performance, low pulsation and low noise.