Noises Cancelling Adaptive Methods in Control Telemetry Systems of Oil Electrical Submersible Pumps

The main ideas of this paper are that only some from more than 10 MATLAB Adaptive Methods library may be useful and can be recommended to filter out High-Noises in similar Control Telemetry Channels of Electric Power Components like ESP Systems: only four of applied have shown successfully good results in the early prediction of the ESP motor real insulation disruption (like Sign-error, Sign-data and Sign-sign filters). The best among the ten analyzed adaptive filter algorithms was recognized to be, The Normalized LMS FIR filter algorithm — adaptfilt.nlm

Evaluating state of health of Li-ion polymer batteries

Günümüzde birçok enerji depolama çözümünde, yüksek enerji ve güç yoğunluklarına sahip olmaları nedeni ile Li-iyon polimer tip hücreler tercih edilmektedir. Li-iyon polimer hücrelerde, elektrotlar arasında bulunan seperatör malzeme elektriksel olarak yalıtkan fakat iyonik olarak iletken bir malzemedir. Bu malzemenin yapısı, hücrenin aşırı zorlanma durumlarında özelliğini kaybetmekte ve hücreyi arızalı konuma düşürerek güvenlik problemleri meydana getirmektedir. Hücrelerde geri döndürülemez değişiklilerin meydana geldiği bölgelerden biri elektrot ile seperatör arası katı elektrolit geçişlerinin yaşandığı bölgedir. Bu çalışmada, elektrokimyasal empedans spektroskopi yöntemi ile li-iyon polimer pillerin hücre kinetik parametreleri elde edilmiştir ve hücrelerin zorlanmış dolma ve boşalma durumlarında bu parametrelerin değişimi kuramsal olarak incelenmiştir. Li-iyon polimer pillerde oluşabilecek yanlış doldurma ve boşaltma işlemleri sebebi ile meydana gelen geri döndürülemez etkilerin klasik hücre modelleri tarafından tam olarak yansıtılamadığı görülmüştür. Bu nedenle çalışmada hücre eşdeğer devre modeli arıza durumularına göre geliştirilmiş ve sınıflandırılmış, yeni geliştirilmiş hücre eşdeğer devresi modeli ile pil sağlamlık durumunun daha iyi yansıtılacağı önerilmiştir. Yapılan deneysel çalışma ile, normal dolma ve boşalma durumlarında klasik pil modelinin, sağlamlık durumunun değerlendirmesi için yeterli olduğu görülmüştür. Aşırı dolma ve boşalma durumlarının ve etkilerinin incelendiği deneysel çalışmalar neticesinde klasik modelin durum değerlendirme için yetersiz kaldığı ispat edilmiş ve bu çalışmada önerilen modelin arıza durumlarını daha gerçekçi biçimde yansıttığı görülmüştür. Anahtar Kelimeler: Li-iyon polimer hücre modeli, aşırı şarj, aşırı deşarj, sağlamlık durumu.As much as the batteries involve to our lives in any technologic area as energy storage devices -in our case Li batteries - gain is much importance. Battery state definition is even more important with the complex energy storage solutions. In most cases having a Battery Management System (BMS) integrated with cells is necessary, because of specific applications. One of the main tasks in Battery Management is the determining the battery state by means of charge and health. The battery manufacturers or suppliers have high concern to have a proper battery for the specific application. Charging and discharging of batteries are critical since it is an external intervention to the cell, exciting cell chemistry. When they are not controlled properly there is high risk for battery state of health and the application. The literature reports various different approaches to estimating state of heath (primarily capacity fade). These include the discharge test, which completely discharge a fully cell in order to determine its total capacity; chemistry dependent methods, such as measuring the electrolyte density; ohmic tests such as resistance, conductance or impedance tests perhaps combined with fuzzy logic algorithms. The impedance techniques have been widely used in the last two decades for investigating the kinetic of primary or secondary cells and determining their state of charge or state of health. Electrochemical impedance spectroscopy method is a time consuming but a well proven technique for impedance measurement. In order to have an idea or make a decision on a "Battery State", state of charge and state of health parameters should be obtained. State of function could easily be evaluated after these determinations. However, state of function may differ according to the operating conditions and it is "user defined". Having the accurate value of state of charge and state of health for detecting failure is very important. Changes in state of charge can be defined as reversible changes in a battery. After proper usage and charging of a battery, effective capacity, internal resistance, open circuit voltage and gas production of the battery yield positive trend comparing the initial values. If this parametric changes act as irreversible changes, battery state of health is affected negatively, comparing to the initial state of the battery. Measuring only the cell terminal voltage and esti-mating the cell status is commonly used technique in most applications, bringing us possible faults while easy measurement technique. On contrary to the fact that, it is possible to detect internal short circuit and cell open circuit while it is not possible to detect irreversible changes on self discharge and internal resistance increase or active power loss by only voltage measurement. Therefore generally a small excitation current signal is applied to cell terminals in order to involve impedance to the measurement parameters. This study aims to identify the measurable parametric changes between cell terminals occur during overcharge and overdischarge process of Li-ion polymer batteries. These parametric chances will give the opportunity to detect and evaluate the failure of the battery. In this study, Li-ion polymer cell kinetic parameters were obtained by electrochemical impedance spectroscopy method and changes in these parameters were analyzed theoretically in cases of forced charging and discharging. It was seen that, classical cell models were not sufficient enough to mirror the irreversible effects on Li-ion polymer cells caused by improper charging and discharging procedures. Therefore cell equivalent circuit was improved and classified according to the failure states and it is suggested that the improved model is better reflecting the cell state of health. Experimental studies denote that classical cell model is sufficient and classical method is proper for state of health determination under normal charging and discharging cases. It was proved by experiments concentrated on overcharge and overdischarge characteristics that classical cell model is not sufficient and suggested new model is more realistic for state of health determination. Keywords: Li-ion polymer battery model, over-charge, overdischarge, state of health

The application of wavelet technique to sensorless control of brushless DC (BLDC) motor

Bu çalışmada fırçasız doğru akım motorunun (FDAM) dalgacık teorisi yardımıyla algılayıcısız olarak kontrolü ve elektrikli otomobile uygulanması amaçlanmıştır. Bu doğrultuda geliştirilen bir kalkış algoritması yöntemiyle, motorun, endüklenen gerilim bilgisinin algılanabileceği belirli bir hıza kadar açık çevrim olarak hızlanması sağlanıp, bu hızdan sonra geribesleme olarak elde edilen beslenmeyen faz endüklenen geriliminden ve faz akımlarından yararlanılarak kapalı çevrim olarak dalgacık dönüşümü yardımıyla fırçasız doğru akım motorunun algılayıcısız kontrolü gerçekleştirilmiştir. Komutasyon anlarının algılayıcısız olarak elde edilmesi sırasında, geliştirilen PID ve Bulanık kontrolör algoritmaları yardımıyla motor hız ve faz akımları gerçek zamanlı olarak denetlenmiştir. Anahtar Kelimeler: Fırçasız DA motoru, bulanık, PID, algılayıcısız, dalgacık, sonlu elemanlar yöntemi (SEY).This paper deals with developing a novel sensorless drive technique for BLDC motors by using wavelet theory. Study adopts two methods of position prediction. The first method involves self phase inductance variation of which finite element analysis is employed. The second method is based upon the induced voltage and zero crossing point estimation. Starting problem is solved by using position inductance function for the first method and by providing a look-up table for each direction of rotation for the second method. The MATLAB/Simulink model of the motor is established and the simulation performances are obtained. A PID and a fuzzy control algorithms are developed, current and speed controlled performance predictions are obtained. Then as an experimental study, BLDC motor?s PWM pulses are produced by DS1005 processor and DS2201 board of dSPACE DSP kit. The time domain currents and induced-voltage waveforms are recorded. The Daubechies wavelet analyses of the experimental and simulation waveforms are obtained with an extra emphasis on commutation intervals. So an algorithm is developed to predict the commutation instants without any position sensor. This procedure is applied experimentally and it is successfully demonstrated that the proposed method described above could be useful for sensorless control of BLDC motors. It is also shown that, results of the simulation model and its wavelet analysis are in a very good agreement with those of experiments.   Keywords: Brushless DC motor, fuzzy, PID, sensorless, wavelet, finite element method (FEM)

Fuzzy supervisory control of Rotor-AMB system and bias current optimization

This paper presents the Fuzzy Supervisory Control (FSC) and bias current optimization algorithm developed for a Rotor-Active Magnetic Bearing (Rotor-AMB) system. Since the AMBs are inherently unstable, it is essential to use a controller for a stable levitation. Initially, a closed loop control of Rotor-AMB system is achieved and the whole model is built in a virtual environment (MatlabÒ/ Simulink). With the help of simulation model the system dynamics is analyzed. In addition to that, the effect of bias current on energy consumption is studied for both unidirectional and differential control current strategies. A diffential current control gives better efficiency compared with a unidirectional approach when the bias current is variable. Thus, optimizing the bias current according to the operational conditions is beneficial for magnetically levitated systems. According to the results obtained an energy optimization algorithm (EOA) is developed. Since the system is nonlinear and has some uncertainties a Fuzzy Supervisory Controller is used to overcome these problems. Then, the real time model of the FSC and EOA are achieved using dSPACE. Finally an experimental set up is formed and FSC+EOA are applied to the Rotor-AMB system. It is shown that, FSC and the algorithm developed make the system tolerant to higher unbalances and disturbances with minimum energy consumption. Keywords: Active magnetic bearing, fuzzy logic, energy.Bu çalışmada, Rotor-Aktif Manyetik Yatak (AMY) sistemi için tasarlanılan Bulanık Denetleyici Kontrolör (BDK) ve sistemde harcanılan enerjiyi azaltmayı sağlayan enerji eniyileştirme algoritması (EİA) sunulmuştur. Başlangıçta sistem dinamiğini incelemek için sisteme ait benzetişim modeli MatlabÒ/ Simulink ortamında gerçekleştirilmiştir. Oluşturulan model ile denge akımının enerji kaybına olan etkisi literatürde yer alan iki farklı yöntemi için incelenmiştir. Elde edilen sonuçlardan hareket ile enerji eniyileştirme algoritması geliştirilmiş ve sistemin kontrolünde kullanılan BDK’ya bağlanmıştır. Gerçekleştirilen BDK+EİA, dSPACE modülü yardımı ile Rotor-AMY sistemine uygulanmıştır. Sonuçta sistem parametrelerinin aynı anda değiştirilmesi ile dinamik yapının uygun katılıkta ve en az enerji harcayacak biçimde çalıştığı deneysel olarak gösterilmiştir. Anahtar Kelimeler: Aktif manyetik yatak, bulanık mantık, enerji

Noises Cancelling Adaptive Methods in Control Telemetry Systems of Oil Electrical Submersible Pumps

The main ideas of this paper are that only some from more than 10 MATLAB Adaptive Methods library may be useful and can be recommended to filter out High-Noises in similar Control Telemetry Channels of Electric Power Components like ESP Systems: only four of applied have shown successfully good results in the early prediction of the ESP motor real insulation disruption (like Sign-error, Sign-data and Sign-sign filters). The best among the ten analyzed adaptive filter algorithms was recognized to be, The Normalized LMS FIR filter algorithm — adaptfilt.nlm