【摘要】：由于一些感應電機需要運行在復雜工況下(例如潛油電機),由于這一類復雜工況下工作的感應電機溫度不易直接測量,其電機內腔溫度也不易散發(fā)。此時電機溫升情況關系到電機長期穩(wěn)定運行的安全性,這就需對復雜工況下運行的感應電機溫度進行狀態(tài)監(jiān)測。尤其在電機負載突變的瞬間,其電流會發(fā)生突變,但電機的溫度卻不會發(fā)生突變。因此,本文針對以上問題進行了研究,將電機定轉子電阻參數(shù)辨識方法與電機等效熱模型進行結合,以實現(xiàn)對電機定轉子側溫度的在線辨識。將模型參考自適應理論應用于電機定轉子電阻的參數(shù)辨識當中,根據(jù)兩相靜止坐標系下的感應電機數(shù)學模型進行推導,可到得到等效轉子磁鏈的電壓與電流模型。通過等效轉子磁鏈的電壓與電流模型可以確定定子和轉子電阻辨識方案的參考模型與可調模型,所做工作可為定轉子電阻各自自適應率的設計提供理論依據(jù)。為了保證定轉子電阻辨識系統(tǒng)的穩(wěn)定性,將超穩(wěn)定不等式應用于定轉子電阻辨識系統(tǒng)誤差方程,得到定轉子電阻對應的各自自適應率。由于電機溫度變化對定轉子電阻的影響,利用電機溫度與金屬電阻的近似線性關系對自適應率中的電阻阻值進行了修正,得到了跟隨電機溫度變化的定轉子電阻辨識方案。通過建模仿真可驗證所建立模型的穩(wěn)定性。由于電機的溫升是因為其所產(chǎn)生的損耗引起的,跟據(jù)感應電機結構得到感應電機兩熱源的等效熱模型。在此基礎上將感應電機散熱系統(tǒng)對電機溫度的影響因素進行考慮,得到修正后的感應電機等效熱模型,利用該模型可以實現(xiàn)對感應電機定轉子側溫度的實時辨識。改進了感應電機溫度辨識系統(tǒng)的平臺,完善了算法平臺。然后進行了恒負載轉矩,變負載轉矩,變壓變負載轉矩以及變頻變負載轉矩的實驗以模擬實際電機運行的復雜工況。通過對不同實驗條件下的實驗辨識溫度與實測溫度的對比分析,二者間的最大誤差小于8℃,且負載突變瞬間溫度辨識結果無突變,體現(xiàn)了算法模型的具有良好的動態(tài)跟隨性,同時也驗證了本文所提出的電機溫度辨識方法的可行性與正確性。
[Abstract]:Since some induction motors need to operate under complex operating conditions (such as submersible motors), the temperature of induction motors operating under this kind of complex working conditions is not easy to be measured directly, and the temperature of the inner cavity of the motors is not easy to emit. In this case, the temperature rise of the motor is related to the safety of the motor running steadily for a long time, so it is necessary to monitor the temperature of the induction motor operating under complex conditions. Especially in the moment of the sudden change of the motor load, the electric current will change, but the temperature of the motor will not change. Therefore, this paper studies the above problems and combines the identification method of resistance parameters of stator and rotor with the equivalent heat model of motor to realize the on-line identification of stator and rotor side temperature of motor. The model reference adaptive theory is applied to the parameter identification of the stator and rotor resistance of the motor. According to the mathematical model of the induction motor in the two-phase stationary coordinate system, the voltage and current model of the equivalent rotor flux can be obtained. The reference model and adjustable model of stator and rotor resistance identification scheme can be determined by the voltage and current model of equivalent rotor flux. The work can provide a theoretical basis for the design of self-adaptive rate of stator and rotor resistance. In order to ensure the stability of the stator and rotor resistance identification system, the superstability inequality is applied to the error equation of the stator and rotor resistance identification system, and the corresponding adaptive rates of the stator and rotor resistance are obtained. Because of the influence of the temperature change of the motor on the stator and rotor resistance, the resistance in the adaptive rate is modified by using the approximate linear relationship between the temperature of the motor and the metal resistance, and the identification scheme of the stator and rotor resistance following the variation of the temperature of the motor is obtained. The stability of the established model can be verified by modeling and simulation. Due to the loss caused by the temperature rise of the motor, the equivalent heat model of the two heat sources of the induction motor is obtained according to the structure of the induction motor. On the basis of this, the influence factors of induction motor heat dissipation system on motor temperature are considered, and the modified equivalent heat model of induction motor is obtained, which can be used to realize the real-time identification of stator and rotor side temperature of induction motor. The platform of induction motor temperature identification system and the algorithm platform are improved. Then the experiments of constant load torque, variable voltage load torque and variable frequency load torque are carried out to simulate the complex operating conditions of the actual motor. Through the comparison and analysis of the experimental identification temperature and the measured temperature under different experimental conditions, the maximum error between them is less than 8 鈩，

本文編號：2268134