CN104167969A

CN104167969A - Position sensor-free control method used for sea wave power generation system

Info

Publication number: CN104167969A
Application number: CN201410232172.1A
Authority: CN
Inventors: 余海涛; 孟高军; 胡敏强; 黄磊
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2014-05-28
Filing date: 2014-05-28
Publication date: 2014-11-26

Abstract

The invention discloses a position sensorless control method for a wave power generation system, which combines a double-pulse nonlinear voltage application method, a sliding mode observer, a neural network controller, and a rotor position anti-interference observer; The sliding mode observer obtains the rotor position information. First, the PMSG back electromotive force EEMF is estimated by the sliding mode observer, and then the error between the measured current and the observed current constitutes a sliding film plane to observe the EEMF, and the rotor position is obtained accurately; at the same time The neural network controller is used to replace the traditional switching function Z, and the equivalent EEMF is obtained to obtain the rotor position detection value. In order to reduce the observation error, the error caused by the phase lag of the low-pass filter is compensated; and the rotor position anti-interference observation is designed. In addition, the rotor initial position angle is calculated by double pulse voltage application method. The invention can accurately and effectively detect the rotor position information of the ocean wave power generation system PMSG in real time.

Description

A position sensorless control method for ocean wave power generation system

技术领域 technical field

本发明涉及一种用于海浪发电系统的无位置传感控制方法，是一种将双脉冲非线性电压施加法、滑模观测器、神经网络控制器和转子位置抗干扰观测器等结合在一起的无位置传感器技术。 The invention relates to a position sensorless control method for a wave power generation system, which combines a double-pulse nonlinear voltage application method, a sliding mode observer, a neural network controller, and a rotor position anti-interference observer. position sensorless technology. the

背景技术 Background technique

传统能源日趋枯竭、环境污染问题恶化，新能源开发迫在眉睫。随着低功耗无线传感器的发展，利用环境清洁可再生能源如太阳能、风能以及波浪能发电制作成微电源为传感器节点提供电能，日益受到各界广泛关注。相比风能与太阳能技术，波浪能发电技术要落后十几年。但是波浪能具有其独特的优势，波能能量密度高,是风能的4～30倍；相比太阳能，波浪能不受天气影响。波浪能发电电源是利用波浪发电制作成的电源，为海洋传感节点供电具有诸多优点。目前，在各种结构的海浪发电系统中，采用永磁同步发电机(PMSG)的方案及其效率较高，具有无需励磁电路等优点，有着重要的地位。特别是在小海浪发电系统中，PMSG由于这些优点而得到了更多的应用。一般情况下，PMSG采用机械式位置传感器来检测转子位置，如光电编码器和旋转变压器。然而，机械式传感器的存在带来了很多弊端：1)电机与控制器之间的连接元件增多，坑干扰能力变差，降低了系统可靠性；2)加大了电机空间尺寸和体积，减少了功率密度，增加了系统的硬件成本和维护成本；3)在高温与强腐蚀环境中，将使传感器性能变差、甚至失效，导致电机驱动系统无法正常工作。以上几点都是造成海浪发电系统不稳定工作的主要原因。故采用无位置传感器技术显得格外的必要。 The depletion of traditional energy sources and the deterioration of environmental pollution make it urgent to develop new energy sources. With the development of low-power wireless sensors, the use of environmentally clean and renewable energy sources such as solar energy, wind energy, and wave energy to produce micro-power supplies to provide electrical energy for sensor nodes has increasingly attracted widespread attention from all walks of life. Compared with wind energy and solar energy technology, wave energy power generation technology is more than ten years behind. However, wave energy has its unique advantages. The energy density of wave energy is high, which is 4 to 30 times that of wind energy. Compared with solar energy, wave energy is not affected by the weather. The wave power generation power supply is a power supply made by using wave power generation, and it has many advantages for powering marine sensor nodes. At present, in various structures of wave power generation systems, the permanent magnet synchronous generator (PMSG) scheme has an important position because of its high efficiency and the advantages of no need for excitation circuits. Especially in small wave power generation systems, PMSG has been more applied due to these advantages. Generally, PMSG uses mechanical position sensors to detect the rotor position, such as photoelectric encoders and resolvers. However, the existence of mechanical sensors has brought many disadvantages: 1) The number of connection elements between the motor and the controller increases, the pit interference ability becomes worse, and the system reliability is reduced; 2) The space size and volume of the motor are increased, reducing the The power density is increased, and the hardware cost and maintenance cost of the system are increased; 3) In a high temperature and strong corrosive environment, the performance of the sensor will deteriorate or even fail, resulting in the failure of the motor drive system to work normally. The above points are the main reasons for the unstable operation of the wave power generation system. Therefore, the use of position sensorless technology is particularly necessary. the

而无传感器的核心是控制系统能对转子的实时位置和速度进行准确的估算，常用无传感器的控制方法可分为3类： The core of sensorless is that the control system can accurately estimate the real-time position and speed of the rotor. The commonly used sensorless control methods can be divided into three categories:

(1)采用电机理想模型的开环计算法，如直接计算法、反电动势积分法等；基于开环的计算方法简单直接、动态性能较好；但计算时依赖电机参数，而电机运行时参数总处于变化之中，这样势必会影响转子位置估计的准确性；并且在电机速度很低时，反电动势非常小，容易和各种干扰信号掺杂在一起，信噪比变低，使得反电势难于检测。所以这种方法并不适合用于电机静止或低速时无传感器位置估算。 (1) The open-loop calculation method of the ideal model of the motor is adopted, such as the direct calculation method, the back electromotive force integration method, etc.; the calculation method based on the open-loop is simple and direct, and the dynamic performance is good; but the calculation depends on the motor parameters, and the parameters of the motor during operation It is always changing, which will inevitably affect the accuracy of rotor position estimation; and when the motor speed is very low, the back electromotive force is very small, and it is easy to be mixed with various interference signals, and the signal-to-noise ratio becomes low, making the back electromotive force Difficult to detect. So this method is not suitable for sensorless position estimation when the motor is stationary or at low speed. the

(2)基于外部高频信号注入的转子位置辨识方案，如旋转高频电压注入法、旋转高频电压注入法和旋转高频电流注入法。高频信号注入法是通过给电机三相绕组注入高频信号(电压或电流信号)，依靠电机转子自身的凸极性或由于饱和导致的凸极效应，使高频信号产生的磁场受到转子凸极的调制作用，因此高频信号中将带有转子位置信息，再将高频信号从定子电流或电压中解调出来就能提取出电机转子的位置信息。这种方法依靠外加激励信号，并不依赖于转速，但估算转子位置所需要的时间较长，位置量更新频率不高，所以高频信号注入法在电机静止和低速时有更好的估算效果。 (2) Rotor position identification schemes based on external high-frequency signal injection, such as rotating high-frequency voltage injection method, rotating high-frequency voltage injection method and rotating high-frequency current injection method. The high-frequency signal injection method is to inject a high-frequency signal (voltage or current signal) into the three-phase winding of the motor, relying on the saliency of the motor rotor itself or the saliency effect caused by saturation, so that the magnetic field generated by the high-frequency signal is affected by the saliency of the rotor. Therefore, the high-frequency signal will contain rotor position information, and then the high-frequency signal can be demodulated from the stator current or voltage to extract the position information of the motor rotor. This method relies on an external excitation signal and does not depend on the rotational speed, but it takes a long time to estimate the rotor position, and the update frequency of the position value is not high, so the high-frequency signal injection method has a better estimation effect when the motor is stationary and at low speed . the

(3)基于状态观测器的闭环算法，如滑模观测器法(SMO)、模型参考自适应系统法(MRAS)、扩展卡尔曼滤波器法(EKF)等。观测器的本质就是系统状态重构，即重新构造一个系统，利用原系统中直接可以测到的输出向量和输入向量作为它的输入信号，并使重构系统的输出信号在一定的条件下等价于原系统的状态，这个重新构造的系统就称为观测器。 (3) Closed-loop algorithms based on state observers, such as sliding mode observer method (SMO), model reference adaptive system method (MRAS), extended Kalman filter method (EKF), etc. The essence of the observer is system state reconstruction, that is, to reconstruct a system, use the output vector and input vector that can be directly measured in the original system as its input signal, and make the output signal of the reconstructed system equal to Based on the state of the original system, this reconstructed system is called an observer. the

发明内容 Contents of the invention

发明目的：为了克服现有技术中存在的不足，本发明提供一种用于海浪发电系统的无位置传感控制方法，将双脉冲非线性电压施加法、滑模观测器、神经网络控制器和转子位置抗干扰观测器等结合在一起，在有效的对海浪发电系统PMSG转子初始估计的同时，可以准确、有效的实时检测海浪发电系统PMSG运行后的转子位置信息。 Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a position-sensing-free control method for ocean wave power generation systems, which combines a double-pulse nonlinear voltage application method, a sliding mode observer, a neural network controller and Combined with the rotor position anti-interference observer, etc., it can accurately and effectively detect the rotor position information of the PMSG after the operation of the ocean wave power generation system in real time while effectively initially estimating the PMSG rotor of the ocean wave power generation system. the

技术方案：为实现上述目的，本发明采用的技术方案为： Technical scheme: in order to achieve the above object, the technical scheme adopted in the present invention is:

一种用于海浪发电系统的无位置传感控制方法，将双脉冲非线性电压施加法、滑模观测器、神经网络控制器和转子位置抗干扰观测器等结合在一起，具体包括以下步骤： A position sensorless control method for an ocean wave power generation system, which combines a double-pulse nonlinear voltage application method, a sliding mode observer, a neural network controller, and a rotor position anti-interference observer, and specifically includes the following steps:

(1)转子初始位置检测采用双脉冲电压施加法，根据交、直轴电感差异原理，向电机施加2个方向不同、幅值相同的等宽电压矢量，检测到两次电流响应，从而解出与转子位置构成函数关系的差分电感分量，最终根据所述函数关系得出转子初始位置角； (1) The initial position detection of the rotor adopts the double-pulse voltage application method. According to the principle of the difference between the alternating and direct axis inductance, two equal-width voltage vectors with different directions and the same amplitude are applied to the motor, and the two current responses are detected, so as to solve The differential inductance component that forms a functional relationship with the rotor position, and finally obtains the initial rotor position angle according to the functional relationship;

(2)海浪发电系统开始运行后，采用反电动势来检测转子位置，采用滑模观测器获取转子位置信息：首先采用滑膜观测器对等效扩展反电动势EEMF进行估算，随后通过检测电流和观测电流之间的误差构成模滑面对等效扩展反电动势EEMF进行观测，从而获得转子位置检测值；为了减小位置估算误差，对低通滤波器相位滞后产生的误差进行补偿； (2) After the wave power generation system starts to operate, the back electromotive force is used to detect the rotor position, and the sliding mode observer is used to obtain the rotor position information: firstly, the sliding film observer is used to estimate the equivalent extended back electromotive force EEMF, and then by detecting the current and observing The error between the currents constitutes a model sliding surface to observe the equivalent extended back electromotive force EEMF, so as to obtain the rotor position detection value; in order to reduce the position estimation error, the error caused by the phase lag of the low-pass filter is compensated;

(3)为削弱滑模观测器的抖振现象，采用神经网络控制器代替传统的开关函数Z，得到等效扩展反电动势EEMF；神经网络控制器同时反映出检测电流、观测电流以及两者之间的差值对等效反电动势EEMF的控制的作用； (3) In order to weaken the chattering phenomenon of the sliding mode observer, a neural network controller is used instead of the traditional switching function Z to obtain the equivalent extended back electromotive force EEMF; The effect of the difference between them on the control of the equivalent back electromotive force EEMF;

(4)当海浪发电系统因为海浪的不平稳运行而产生大于阈值的扰动转矩时，启动转子位置扰动抵抗观测器，解决在海浪不平稳运行条件下的干扰而可能导致的滑膜观测器检测的到位置信号误差逐渐变大，甚至脱离实际值的状态。 (4) When the wave power generation system generates a disturbance torque greater than the threshold due to the unstable operation of the waves, the rotor position disturbance resistance observer is started to solve the detection of the synovial film observer that may be caused by the disturbance under the condition of the unstable operation of the waves The error of the position signal becomes larger gradually, and even deviates from the state of the actual value. the

有益效果：本发明提供的用于海浪发电系统的无位置传感控制方法，将双脉冲非线性电压施加法、滑模观测器、神经网络控制器和转子位置抗干扰观测器等结合在一起，相较于现有技术，具有如下优势：1、初始位置检测采用双脉冲线性电压注入法的方式，向海浪发电系统PMGM的电枢绕组施加空间电压矢量，能够非常准确的检测海浪发电系统PMGM的转子初始位置；2、节约了硬件成本和维修成体，同时提高了系统的抗干扰性和鲁棒性；3、为了削弱滑模观测器的抖振现象，采用神经网络控制器代替传统开关函数Z，得到等效EEMF；4、有效解决在海浪的不稳定波动而可能导致观测器检测的到位置信号误差逐渐变大，甚至脱离实际值的状态。 Beneficial effects: The position sensorless control method for ocean wave power generation system provided by the present invention combines the double-pulse nonlinear voltage application method, sliding mode observer, neural network controller and rotor position anti-interference observer, etc., Compared with the existing technology, it has the following advantages: 1. The initial position detection adopts the double-pulse linear voltage injection method, and the space voltage vector is applied to the armature winding of the wave power generation system PMGM, which can detect the PMGM of the wave power generation system very accurately. The initial position of the rotor; 2. It saves hardware cost and maintenance costs, and at the same time improves the anti-interference and robustness of the system; 3. In order to weaken the chattering phenomenon of the sliding mode observer, a neural network controller is used to replace the traditional switching function Z , to obtain the equivalent EEMF; 4. Effectively solve the unstable fluctuation of ocean waves that may cause the error of the position signal detected by the observer to gradually increase, or even deviate from the actual value. the

附图说明 Description of drawings

图1为PMSG模型； Fig. 1 is PMSG model;

图2为空间电压矢量分布图； Figure 2 is a space voltage vector distribution diagram;

图3为带有滑模观测器的扩展反电动势检测法原理图； Figure 3 is a schematic diagram of the extended back EMF detection method with a sliding mode observer;

图4为转子位置抗干扰观测器观测原理图； Fig. 4 is the observation principle diagram of the rotor position anti-jamming observer;

图5为神经网络工作原理图； Fig. 5 is the working principle diagram of neural network;

图6为电流传感器调理电路原理图。 Figure 6 is a schematic diagram of the current sensor conditioning circuit. the

具体实施方式 Detailed ways

下面结合附图对本发明作更进一步的说明。 The present invention will be further described below in conjunction with the accompanying drawings. the

下面就本发明的设计思想等内容加以具体说明。 In the following, the design idea and other contents of the present invention will be described in detail. the

如图1所示为PMSG模型，在定子静止两相αβ坐标系下，PMSG的数学模型可表示为： The PMSG model is shown in Figure 1. In the static two-phase αβ coordinate system of the stator, the mathematical model of the PMSG can be expressed as:

$[\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] = = R R [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] + + [\begin{matrix} {L L}_{11} + + {L L}_{22} cos cos 22 {θ θ}_{r r} & 22 sin sin {θ θ}_{r r} \\ {L L}_{22} sin sin 22 {θ θ}_{r r} & {L L}_{11} - - {L L}_{22} cos cos 22 {θ θ}_{r r} \end{matrix}] . . D D. [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] + + {w w}_{r r} {ψ ψ}_{PM PM} [\begin{matrix} - - cos cos {θ θ}_{r r} \\ sin sin {θ θ}_{r r} \end{matrix}] - - - - - - ((11))$

其中， in,

$\{\begin{matrix} {L L}_{11} = = (({L L}_{d d} + + {L L}_{q q})) / / 22 \\ {L L}_{22} = = (({L L}_{d d} - - {L L}_{q q})) / / 22 \end{matrix} - - - - - - ((22))$

式中，u和i为αβ坐标系下的定子电压和定子电流，R为定子相电阻；ψ_PM为永磁磁链；θ_r为转子位置；w_r为PMSG电角速度；L_d、L_q分为PMSG的d轴电感和q轴电感；D为微分算子。当PMSG处于静止状态时，其反电动势为零，故式(1)可以简写为： In the formula, u and i are the stator voltage and stator current in the αβ coordinate system, R is the stator phase resistance; ψ _PM is the permanent magnet flux linkage; θ _r is the rotor position; w _r is the electrical angular velocity of the PMSG; L _d , L _q It is divided into d-axis inductance and q-axis inductance of PMSG; D is a differential operator. When the PMSG is at rest, its counter electromotive force is zero, so formula (1) can be abbreviated as:

$[\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] = = R R [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] + + [\begin{matrix} {L L}_{11} + + {L L}_{22} cos cos 22 {θ θ}_{r r} & 22 sin sin {θ θ}_{r r} \\ {L L}_{22} sin sin 22 {θ θ}_{r r} & {L L}_{11} - - {L L}_{22} cos cos 22 {θ θ}_{r r} \end{matrix}] . . D D. [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] - - - - - - ((33))$

若对PMSG定子施加2次方向不同，幅值相同的2次电压矢量(具体施加规则见图2的任意两个不同的电压矢量，如V₁或V₂，通过电流传感器检测2次电流响应值，随后解出电感矩阵方程为： If two voltage vectors with different directions and the same amplitude are applied to the PMSG stator (see any two different voltage vectors in Figure 2 for the specific application rules, such as V ₁ or V ₂ , the secondary current response value is detected by the current sensor , and then solve the inductance matrix equation as:

$[\begin{matrix} {μ μ}_{α α 11} & {μ μ}_{α α 22} \\ {μ μ}_{β β 11} & {μ μ}_{β β 22} \end{matrix}] = = R R [\begin{matrix} {i i}_{α α 11} & {i i}_{α α 22} \\ {i i}_{β β 11} & {i i}_{β β 22} \end{matrix}] + + [\begin{matrix} {L L}_{11} + + {L L}_{22} cos cos 22 {θ θ}_{r r} & 22 sin sin {θ θ}_{r r} \\ {L L}_{22} sin sin 22 {θ θ}_{r r} & {L L}_{11} - - {L L}_{22} cos cos 22 {θ θ}_{r r} \end{matrix}] D D. [\begin{matrix} {i i}_{α α 11} & {i i}_{α α 22} \\ {i i}_{β β 11} & {i i}_{β β 22} \end{matrix}] - - - - - - ((44))$

$\begin{matrix} [\begin{matrix} {L L}_{1111} & {L L}_{1212} \\ {L L}_{21 twenty one} & {L L}_{22 twenty two} \end{matrix}] = = [\begin{matrix} {L L}_{11} + + {L L}_{22} cos cos 22 {θ θ}_{r r} & 22 sin sin {θ θ}_{r r} \\ {L L}_{22} sin sin 22 {θ θ}_{r r} & {L L}_{11} - - {L L}_{22} cos cos 22 {θ θ}_{r r} \end{matrix}] \\ = = [\begin{matrix} {μ μ}_{α α 11} - - {Ri Ri}_{α α 11} & {μ μ}_{α α 11} - - {Ri Ri}_{α α 22} \\ {μ μ}_{β β 11} - - {Ri Ri}_{β β 11} & {μ μ}_{β β 22} - - {Ri Ri}_{β β 22} \end{matrix}] [\begin{matrix} \frac{{di di}_{α α 11}}{dt dt} & \frac{{di di}_{α α 22}}{dt dt} \\ \frac{{di di}_{β β 11}}{dt dt} & \frac{{di di}_{β β 22}}{dt dt} \end{matrix}] \end{matrix} - - - - - - ((55))$

根据是(5)，转子位置可由下式获得： According to (5), the rotor position can be obtained by the following formula:

${θ θ}_{r r} = = \frac{11}{22} {tan the tan}^{- - 11} \frac{{L L}_{1212} + + {L L}_{21 twenty one}}{{L L}_{1111} - - {L L}_{22 twenty two}} - - - - - - ((66))$

根据式(6)即可得出PMSG转子初始位置角。 According to formula (6), the initial position angle of the PMSG rotor can be obtained. the

当电机处于运行状态后，采用滑膜观测器来获取PMSG转子位置信息，结构框图如图3所示，在d-q旋转坐标系中PMSG的电压方程为： When the motor is in the running state, the synovial film observer is used to obtain the position information of the PMSG rotor. The structural block diagram is shown in Figure 3. The voltage equation of the PMSG in the d-q rotating coordinate system is:

$[\begin{matrix} {u u}_{d d} \\ {u u}_{q q} \end{matrix}] = = [\begin{matrix} R R + + {DL DL}_{d d} & - - {w w}_{r r} {L L}_{d d} \\ {w w}_{r r} {L L}_{d d} & R R + + {DL DL}_{q q} \end{matrix}] [\begin{matrix} {i i}_{d d} \\ {i i}_{q q} \end{matrix}] + + [\begin{matrix} 00 \\ {w w}_{r r} {K K}_{E E.} \end{matrix}] - - - - - - ((77))$

其中，[u_d u_q]^T为旋转坐标系下电压；[i_d i_q]^T为旋转坐标系下电流；R为定子电阻；D为微分算子；w_r为转子角速度(电角度)；K_E为反电势常数；L_d为d轴电感；L_q为q轴电感。 Among them, [u _d u _q ] ^T is the voltage in the rotating coordinate system; [i _d i _q ] ^T is the current in the rotating coordinate system; R is the stator resistance; D is the differential operator; w _r is the rotor angular velocity (electrical angle) ; K _E is the back EMF constant; L _d is the d-axis inductance; L _q is the q-axis inductance.

将式(7)变换到α-β静止坐标系下，得到： Transform formula (7) into the α-β static coordinate system to get:

$[\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] = = [\begin{matrix} R R + + {DL DL}_{α α} & - - {w w}_{r r} {L L}_{αβ αβ} \\ {w w}_{r r} {L L}_{αβ αβ} & R R + + D D. {L L}_{β β} \end{matrix}] [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] + + {w w}_{r r} {K K}_{E E.} [\begin{matrix} - - sin sin {θ θ}_{r r} \\ cos cos {θ θ}_{r r} \end{matrix}] - - - - - - ((88))$

[u_α u_β]^T为旋转坐标系下电压；[i_α i_β]^T为旋转坐标系下电流；L_α＝L_o+L₁cos2θ_r；L_αβ＝L₁sin2θ_r；L_β＝L_o-L₁cos2θ_r；L_o＝(L_d+L_q)/2；L₁＝(L_d-L_q)/2；θ_r为海浪发电系统在运行时的PMSG位置角。 [u _α u _β ] ^T is the voltage in the rotating coordinate system; [i _α i _β ] ^T is the current in the rotating coordinate system; L _α ＝L _o +L ₁ cos2θ _r ; L _αβ ＝L ₁ sin2θ _r ; L _β ＝ L _o -L ₁ cos2θ _r ; L _o =(L _d +L _q )/2; L ₁ =(L _d -L _q )/2; θ _r is the PMSG position angle of the ocean wave power generation system during operation.

式(8)中包含有θ_r、2θ_r项，其中2θ_r将给后期的计算带来很大的难度，因此，可以通过适当的变换使其消除，从式(8)中可以看出：电感矩阵的不对称是2θ_r的出现的主要原因，因而，将d-q轴下的PMSG的电压方程(7)重写为： Equation (8) contains the terms θ _r and 2θ _r , among which 2θ _r will bring great difficulty to the later calculation, so it can be eliminated by appropriate transformation, as can be seen from equation (8): The asymmetry of the inductance matrix is the main reason for the appearance of 2θ _r , therefore, the voltage equation (7) of the PMSG under the dq axis is rewritten as:

$[\begin{matrix} {u u}_{d d} \\ {u u}_{q q} \end{matrix}] = = [\begin{matrix} R R + + {DL DL}_{d d} & - - {w w}_{r r} {L L}_{q q} \\ {w w}_{r r} {L L}_{q q} & R R + + {DL DL}_{d d} \end{matrix}] [\begin{matrix} {i i}_{d d} \\ {i i}_{q q} \end{matrix}] + + [\begin{matrix} 00 \\ {w w}_{r r} {K K}_{E E.} + + (({L L}_{d d} - - {L L}_{q q})) (({w w}_{r r} {i i}_{d d} - - {di di}_{q q} / / dt dt)) \end{matrix}] - - - - - - ((99))$

将式(9)变换到α-β静止坐标系下，得： Transform the formula (9) into the α-β static coordinate system, and get:

$\begin{matrix} [\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] = = [\begin{matrix} R R + + {DL DL}_{d d} & {w w}_{r r} (({L L}_{d d} - - {L L}_{q q})) \\ - - {w w}_{r r} (({L L}_{d d} - - {L L}_{q q})) & R R + + {DL DL}_{d d} \end{matrix}] [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] \\ + + [[(({w w}_{r r} {K K}_{E E.} + + (({L L}_{d d} - - {L L}_{q q})) (({w w}_{r r} {i i}_{d d} - - \frac{{di di}_{q q}}{dt dt}))]] \begin{matrix} [\begin{matrix} - - sin sin {θ θ}_{r r} \\ cos cos {θ θ}_{r r} \end{matrix}] \end{matrix} \end{matrix} - - - - - - ((1010))$

为了便于使用滑膜观测器对反电动势进行观测，将电压方程(7)改写成电流的状态方程形式： In order to facilitate the observation of back electromotive force with a synovial film observer, the voltage equation (7) is rewritten into the form of the state equation of the current:

$\frac{d d}{dt dt} [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] = = A A \cdot \cdot [\begin{matrix} {i i}_{α α} \\ {i i}_{β β} \end{matrix}] + + \frac{11}{{L L}_{d d}} [\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] + + \frac{E E.}{{L L}_{d d}} [\begin{matrix} sin sin {θ θ}_{m m} \\ - - cos cos {θ θ}_{m m} \end{matrix}] - - - - - - ((1111))$

其中， $A = \frac{1}{L_{d}} [\begin{matrix} - R & - ω_{r} (L_{d} - L_{q}) \\ ω_{r} (L_{d} - L_{q}) & - R \end{matrix}],$ in, $A = \frac{1}{L_{d}} [\begin{matrix} - R & - ω_{r} (L_{d} - L_{q}) \\ ω_{r} (L_{d} - L_{q}) & - R \end{matrix}],$

$E = [\begin{matrix} E_{α} \\ E_{β} \end{matrix}] = [(w_{r} K_{E} + (L_{d} - L_{q}) (w_{r} i_{d} - \frac{{di}_{q}}{dt})] [\begin{matrix} - \sin θ_{r} \\ \cos θ_{r} \end{matrix}],$ 且E为反电动势。 $E. = [\begin{matrix} {E.}_{α} \\ {E.}_{β} \end{matrix}] = [(w_{r} K_{E.} + (L_{d} - L_{q}) (w_{r} i_{d} - \frac{{di}_{q}}{dt})] [\begin{matrix} - \sin θ_{r} \\ \cos θ_{r} \end{matrix}],$ And E is the counter electromotive force.

构造如下的滑膜观测器： Construct the synovium observer as follows:

$\frac{d d}{dt dt} [\begin{matrix} {\overset{^^}{i i}}_{α α} \\ {\overset{^^}{i i}}_{β β} \end{matrix}] = = A A \cdot &Center Dot; [\begin{matrix} {\overset{^^}{i i}}_{α α} \\ {\overset{^^}{i i}}_{β β} \end{matrix}] + + \frac{11}{{L L}_{d d}} [\begin{matrix} {μ μ}_{α α} \\ {μ μ}_{β β} \end{matrix}] + + \frac{{Z Z}_{αβ αβ}}{{L L}_{d d}} - - - - - - ((1212))$

其中，为定子α和β轴电流观测值；为了削弱滑模观测器的抖振现象，采用神经网络控制器代替传统开关函数Z_αβ，具体结构图如图5所示。 in, are the stator α and β axis current observations; in order to weaken the chattering phenomenon of the sliding mode observer, a neural network controller is used to replace the traditional switching function Z _αβ , the specific structure diagram is shown in Figure 5.

神经网络速度控制器要反应实测电流i_αβ，观测电流与两者差值之间差值ε_αβ对扩展反电动势EEMF的控制的作用；其输出量代替传统的开关函数Z_αβ。 The neural network speed controller should respond to the measured current i _αβ and observe the current The effect of the difference between the difference ε _αβ on the control of the extended back electromotive force EEMF; its output Instead of the traditional switch function Z _αβ .

神经网络控制器设计采用3层网络：输入层、隐含层和输出层，如图5所示。输入层有3个输入量i_αβ和ε_αβ；隐含层有6个神经元；输出层是 The neural network controller design uses a 3-layer network: input layer, hidden layer and output layer, as shown in Figure 5. The input layer has 3 inputs i _αβ and ε _αβ ; the hidden layer has 6 neurons; the output layer is

输入层：由3个神经元组成 Input layer: consists of 3 neurons

σ₂＝i_αβ σ₃＝ε_αβ σ ₂ =i _αβ σ ₃ =ε _αβ

o_i(t)＝σ_i i＝1,2,3 o _i (t) = σ _i i = 1,2,3

${n no}_{22 j j} ((t t)) = = {Σ Σ}_{i i = = 11}^{66} {w w}_{ji the ji} {o o}_{i i} ((t t)) + + {θ θ}_{22 j j},, i i = = 1,2,3 1,2,3$

隐含层：由6个神经元组成 Hidden layer: composed of 6 neurons

o_2j(t)＝f₁[n_2j(t)] j＝1,2,...,6 o _2j (t)=f ₁ [n _2j (t)] j=1,2,...,6

${n no}_{33} ((t t)) = = {Σ Σ}_{j j = = 11}^{66} {w w}_{33 j j} {o o}_{22 j j} ((t t)) + + {θ θ}_{33},, j j = = 1,2 1,2,, . . . . . .,, 66$

输出层：由1个神经元组成 Output layer: composed of 1 neuron

o₃(t)＝f₂[n₃(t)] o ₃ (t) = f ₂ [n ₃ (t)]

选择不同的输出函数可以增强网络的映射功能，且提高网络收敛速度。隐含层的输出函数为logsigmoid函数，输出层的输出函数为trnsig moid函数。 Choosing different output functions can enhance the mapping function of the network and improve the convergence speed of the network. The output function of the hidden layer is the logsigmoid function, and the output function of the output layer is the trnsigmoid function. the

${f f}_{11} ((x x)) = = log log sig sig ((x x)) = = \frac{11}{11 + + {e e}^{- - x x}}$

${f f}_{22} ((x x)) = = tan the tan sig sig ((x x)) = = \frac{11 - - {e e}^{- - 22 x x}}{11 + + {e e}^{- - 22 x x}}$

$Z_{αβ} = [ksgn ({\hat{i}}_{α} - i_{α}), - ksgn ({\hat{i}}_{β} - i_{β})],$ k为滑模增益。 $Z_{αβ} = [ksgn ({\hat{i}}_{α} - i_{α}), - ksgn ({\hat{i}}_{β} - i_{β})],$ k is the sliding mode gain.

公式(12)减去公式(11)，得到电流观测误差的状态方程为： Subtracting formula (11) from formula (12), the state equation of current observation error is obtained as:

当满如下条件时，滑模观测器进入滑模状态： When the following conditions are met, the sliding mode observer enters the sliding mode state:

$[[{i i}_{α α} - - {\overset{^^}{i i}}_{α α},, {i i}_{β β} - - {\overset{^^}{i i}}_{β β}]] \frac{d d}{t t} [\begin{matrix} {i i}_{α α} - - {\overset{^^}{i i}}_{α α} \\ {i i}_{β β} - - {\overset{^^}{i i}}_{β β} \end{matrix}] < < 00 - - - - - - ((1414))$

若滑模增益k足够大，不等式(18)成立，系统进入滑膜状态，有 If the sliding mode gain k is large enough, the inequality (18) holds true, and the system enters the sliding film state, with

$\frac{d d}{t t} [\begin{matrix} {i i}_{α α} - - {\overset{^^}{i i}}_{α α} \\ {i i}_{β β} - - {\overset{^^}{i i}}_{β β} \end{matrix}] = = [\begin{matrix} {i i}_{α α} - - {\overset{^^}{i i}}_{α α} \\ {i i}_{β β} - - {\overset{^^}{i i}}_{β β} \end{matrix}] = = 00 - - - - - - ((1515))$

将上式(15)代入到公式(13)，得： Substituting the above formula (15) into formula (13), we get:

Z＝E (16) Z＝E (16)

其中Z中包含有不连续高频信号，因此为去除不连续高频信号，将其通入低通滤波器后得到等价控制量，即： Among them, Z contains discontinuous high-frequency signals, so in order to remove discontinuous high-frequency signals, the equivalent control amount is obtained after passing them into a low-pass filter, namely:

$[\begin{matrix} {Z Z}_{α α} \\ {Z Z}_{β β} \end{matrix}] = = [\begin{matrix} {E E.}_{α α} \\ {E E.}_{β β} \end{matrix}] = = [[(({w w}_{r r} {K K}_{E E.} + + (({L L}_{d d} - - {L L}_{q q})) (({w w}_{r r} {i i}_{d d} - - \frac{{di di}_{q q}}{dt dt}))]] [\begin{matrix} - - sin sin {θ θ}_{r r} \\ cos cos {θ θ}_{r r} \end{matrix}] - - - - - - ((1717))$

由公式(17)，可以得到PMSG在高速运行时的转子位置角θ_r From formula (17), the rotor position angle θ _r of the PMSG at high speed can be obtained

${θ θ}_{r r} = = arctan arctan ((- - \frac{{E E.}_{α α}}{{E E.}_{β β}})) - - - - - - ((1818))$

为了减小观测误差，对低通滤波器相位滞后产生的误差进行补偿，补偿值为： In order to reduce the observation error, the error caused by the phase lag of the low-pass filter is compensated, and the compensation value is:

${\overset{^^}{θ θ}}_{re re} = = arctan arctan ((\frac{{w w}_{r r}}{{w w}_{cutoff cut off}})) - - - - - - ((1919))$

其中，w_cutoff＝1/τ₀是低通滤波器的截止频率，τ₀是低通滤波器的时间常数。 Among them, w _cutof f=1/τ ₀ is the cutoff frequency of the low-pass filter, and τ ₀ is the time constant of the low-pass filter.

为了防止海浪发电系统在高速运行时，由于风速阻力而使得转子位置观测值收敛得的情况，为了解决这项问题，本发明专利加入转子位置抗干扰观测器，其具体的工作原理如下： In order to prevent the observed value of the rotor position from converging due to wind speed resistance when the wave power generation system is running at high speed, in order to solve this problem, the patent of the present invention adds a rotor position anti-interference observer, and its specific working principle is as follows:

检测θ_hr为T₁时刻所检测的位置角，为T₂时刻所检测到的位置角，且T₂-T₁＝20ms，设位置误差信号并将ξ作为输入，并加入矩阵前馈输入，根据PMSG的机械运动模型，可构造PMSG转子位置观测器等效结构图。位置误差信号通过线性反馈构造状态观测，从而实现对转子位置的观测。电磁转矩的二阶微分项为一阶微分，为二阶微分)看作是观测器的等效输入，从而可以兼顾不同风速下所产生变化率不同的负载扰动情况，使观测器有足够的坑扰能力。 Detecting θ _hr is the position angle detected at time T ₁ , is the position angle detected at T ₂ time, and T ₂ -T ₁ = 20ms, set the position error signal Taking ξ as input and adding matrix feedforward input, according to the mechanical motion model of PMSG, the equivalent structure diagram of PMSG rotor position observer can be constructed. The position error signal constructs the state observation through the linear feedback, so as to realize the observation of the rotor position. The Second Order Differential Term of Electromagnetic Torque is the first order differential, is the second-order differential) as the equivalent input of the observer, so that the load disturbance with different change rates under different wind speeds can be taken into account, so that the observer has sufficient pit disturbance capability.

PMSG转子位置观测器的机械状态方程可表示为： The mechanical state equation of the PMSG rotor position observer can be expressed as:

$\overset{\cdot &Center Dot;}{X x} = = AX AX + + Bu Bu - - - - - - ((2020))$

y＝CX (21) y=CX (21)

式中： $\overset{\cdot}{X} = {[\begin{matrix} {\overset{\cdot}{T}}_{e} & T_{e} & w_{r} & θ_{r} \end{matrix}]}^{T};$ $u = {\overset{\cdot \cdot}{T}}_{e};$ y＝θ_r； $A = [\begin{matrix} 0 & 0 & 0 & 0 \\ 1 & 0 & 0 & 0 \\ 0 & \frac{1}{J} & 0 & 0 \\ 0 & 0 & P_{n} & 0 \end{matrix}];$ $B = [\begin{matrix} 1 \\ 0 \\ 0 \\ 0 \end{matrix}];$ $C = [\begin{matrix} 0 \\ 0 \\ 0 \\ 1 \end{matrix}];$ P_n极对数；J为转动惯量。 In the formula: $\overset{&Center Dot;}{x} = {[\begin{matrix} {\overset{&Center Dot;}{T}}_{e} & T_{e} & w_{r} & θ_{r} \end{matrix}]}^{T};$ $u = {\overset{&Center Dot; &Center Dot;}{T}}_{e};$ y = θ _r ; $A = [\begin{matrix} 0 & 0 & 0 & 0 \\ 1 & 0 & 0 & 0 \\ 0 & \frac{1}{J} & 0 & 0 \\ 0 & 0 & P_{no} & 0 \end{matrix}];$ $B = [\begin{matrix} 1 \\ 0 \\ 0 \\ 0 \end{matrix}];$ $C = [\begin{matrix} 0 \\ 0 \\ 0 \\ 1 \end{matrix}];$ P _n pole logarithm; J is moment of inertia.

转子位置观测器的状态方程可以表示为： The state equation of the rotor position observer can be expressed as:

$\overset{\cdot &Center Dot;}{\overset{^^}{X x}} = = [\begin{matrix} 00 & 00 & 00 & 00 \\ 11 & 00 & 00 & 00 \\ 00 & \frac{11}{\overset{^^}{J J}} & 00 & 00 \\ 00 & 00 & {P P}_{n no} & 00 \end{matrix}] \overset{^^}{X x} + + [\begin{matrix} 11 \\ 00 \\ 00 \\ 00 \end{matrix}] u u + + [\begin{matrix} {l l}_{11} \\ {l l}_{22} \\ \frac{{l l}_{33}}{\overset{^^}{J J}} \\ \frac{{l l}_{44}}{\overset{^^}{J J}} \end{matrix}] ((y the y - - \overset{^^}{y the y})) - - - - - - ((22 twenty two))$

定义公式(22)中 $[\begin{matrix} l_{1} & l_{2} & \frac{l_{3}}{\hat{J}} & \frac{l_{4}}{\hat{J}} \end{matrix}]$ 为反馈矩阵。 In the definition formula (22) $[\begin{matrix} l_{1} & l_{2} & \frac{l_{3}}{\hat{J}} & \frac{l_{4}}{\hat{J}} \end{matrix}]$ is the feedback matrix.

根据图4所示的位置观测器的结构，可以建立位置观测误差与扰动转矩的传函关系式： According to the structure of the position observer shown in Fig. 4, the relationship between position observation error and disturbance torque can be established as follows:

${Δθ Δθ}_{e e} ((s the s)) = = \frac{- - \frac{\overset{^^}{J J}}{J J} {s the s}^{22}}{\overset{^^}{J J} {s the s}^{44} + + {l l}_{44} {s the s}^{33} + + {l l}_{33} {s the s}^{22} + + {l l}_{22} s the s + + {l l}_{11}} {T T}_{d d} ((s the s)) - - - - - - ((23 twenty three))$

式中T_d(s)为因海浪不稳定而引起的扰动转矩。 where T _d (s) is the disturbance torque caused by unstable sea waves.

由公式(23)可知，因海浪发电系统因为海浪的不平稳运行而产生很大的扰动转矩时，启动转子位置扰动抵抗观测器，解决在海浪的不稳定波动而可能导致观测器检测的到位置信号误差逐渐变大，甚至脱离实际值的状态。 From the formula (23), it can be known that when the wave power generation system generates a large disturbance torque due to the unstable operation of the waves, the rotor position disturbance resistance observer is started to solve the problem that may be detected by the observer due to the unstable fluctuation of the waves. The error of the position signal becomes larger gradually, and even deviates from the state of the actual value. the

由于本实验过程中，对电流采样的要求比较高，故设计了一种电流采样信号调理电路如图6，LSTR15-NP第10引脚是基准电压输入，默认值为2.5V，第9引脚是电压信号输出端。运放LM358对电压信号具有跟随和驱动的作用，与输出端并联的稳压管保证了输出电压不会超出板卡接收的范围。 Due to the relatively high requirements for current sampling during this experiment, a current sampling signal conditioning circuit is designed as shown in Figure 6. The 10th pin of LSTR15-NP is the reference voltage input, the default value is 2.5V, and the 9th pin is the voltage signal output terminal. The operational amplifier LM358 has the function of following and driving the voltage signal, and the regulator tube connected in parallel with the output terminal ensures that the output voltage will not exceed the range received by the board. the

以上所述仅是本发明的优选实施方式，应当指出：对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也应视为本发明的保护范围。 The above is only a preferred embodiment of the present invention, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also possible. It should be regarded as the protection scope of the present invention. the

Claims

1. A sensorless control method for ocean wave power generation system, characterized in that: double-pulse nonlinear voltage application method, sliding mode observer, neural network controller and rotor position anti-jamming observer are combined together, Specifically include the following steps:

(1) The initial position detection of the rotor adopts the double-pulse voltage application method. According to the principle of the difference between the alternating and direct axis inductance, two equal-width voltage vectors with different directions and the same amplitude are applied to the motor, and the two current responses are detected, so as to solve The differential inductance component that forms a functional relationship with the rotor position, and finally obtains the initial rotor position angle according to the functional relationship;

(2) After the wave power generation system starts to operate, the back electromotive force is used to detect the rotor position, and the sliding mode observer is used to obtain the rotor position information: firstly, the sliding film observer is used to estimate the equivalent extended back electromotive force EEMF, and then by detecting the current and observing The error between the currents constitutes a model sliding surface to observe the equivalent extended back electromotive force EEMF, so as to obtain the rotor position detection value; in order to reduce the position estimation error, the error caused by the phase lag of the low-pass filter is compensated;

(3) In order to weaken the chattering phenomenon of the sliding mode observer, a neural network controller is used instead of the traditional switching function Z to obtain the equivalent extended back electromotive force EEMF; The effect of the difference between them on the control of the equivalent extended back electromotive force EEMF;

(4) When the wave power generation system generates a disturbance torque greater than the threshold due to the unstable operation of the waves, the rotor position disturbance resistance observer is started to solve the detection of the synovial film observer that may be caused by the disturbance under the condition of the unstable operation of the waves The error of the position signal becomes larger gradually, and even deviates from the state of the actual value.