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In this paper a systematic model based approach to state estimation for Permanent Magnet Synchronous Motor (PMSM) to built up sensorless drives is presented. A moving horizon estimation (MHE) algorithm is used, an optimization based scheme that yields excellent performance. Under mild assumptions, an optimal problem of type Equality Constrained Quadratic Programming (EQP) is resolved at each iteration...
Distributed energy resources (DER) systems introduce uncertainties in the electrical grid that cannot be addressed by classical deterministic methods. Power system analytic tools, such as Load Flow (LF), should be revisited to address such uncertainties. Probabilistic Load Flow (PLF) provides a solution to this problem by handling these uncertainties as random variables. Among the existing sampling...
Switching models possess discontinuous and nonlinear behavior rendering difficulties in simulations in terms of time consumption, computational complexity causing mathematical instability while equally vulnerable to errors. This issue can be sorted out by averaging detailed models over entire switching period. Several static as well as dynamic average models (full order and reduced order) have been...
Many prediction studies using real life measurements such as wind speed, power, electricity load and rainfall utilize linear autoregressive moving average (ARMA) based models due to their simplicity and general character. However, most of the real life applications exhibit nonlinear character and modelling them with linear time series may become problematic. Among nonlinear ARMA models, polynomial...
Friction modeling plays a very important role in control and simulation systems. A lot of dynamic models are proposed to capture most of the friction behavior observed experimentally. Most dynamic models are typically considered to be dependent only on relative speed and relative displacement of contacting surfaces. However, it is known that dynamic characteristics of friction are affected by other...
In recent years, electric power assisted bicycles become popular in Japan. However the prices of such bicycles are still high because an expensive torque sensor is attached. It is a necessary component to measure human pedaling torque for comfortable motor assistance. Therefore realization of pedaling torque estimation without torque sensor is effective for the cost reduction. In our previous studies,...
Most of the distance relays base their operation on the measured apparent fault impedance. These relays are bound to have an error inflicted by the unknown remote end parameters and fault resistance. This paper presents a method, which diminishes such errors using optimization techniques. The proposed method executes a system model unknown parameter estimation by adjusting model output to measurements...
This paper presents a practical swing-angle estimation method for slung load operations of the multi-rotor unmanned aerial vehicle (UAV), which is essential to maintain the safety during the operation. In order not to rely on extra sensors for monitoring the swing angle, the proposed method in this paper offers an autonomous swing-angle estimation using only an inertial measurement unit (IMU) and...
On a power network, events are desired to be monitored to find its reasons and to take preventive action. Today, power quality measurement devices are used to obtain synchronous measurement data of network, however these devices are expensive and it is not considered a practical option to place one on each node of the network. Therefore, methods estimating voltages and currents at non-measured points...
Several techniques have been developed to estimate the load parameters in power systems. Most of the algorithms mainly focus on estimating the parameters for offline studies. With ongoing smart grid development, high-resolution data at fast rates are available to allow load modeling in real-time. This paper addresses the challenges in online estimation of the load parameters using Phasor Measurement...
Model-based control strategies are widely used to improve the energy efficiency of building systems but they require accurate dynamic building models. Information about disturbances such as lumped load and occupancy is necessary in order to cover the mismatch between the simulations and reality, which leads to determining correct energy predictions of the building. Rigorous models that are applied...
Incentive based demand response (IBDR) offers one of the more promising opportunities for engineering sustainable electricity services. While there are a wide range of studies representing the potential of IBDR program in the power market, understanding customer response needs further study. A key component in all demand response (DR) programs' design is the elasticity which implies customer reaction...
This paper proposes a computationally efficient technique for estimating the composite load model parameters based on analytical similarity of parameter sensitivity. When the model parameters are updated in the optimization procedure to best fit the actual load dynamics, i.e., measurements, parameters of similar sensitivity representation in the given mathematical model structure are updated in the...
This paper analyses the effectiveness of voltage estimations used as a new control logic for a traditional 110/20kV Medium Voltage (MV) On-Load Tap Changing (OLTC) transformer in order to regulate over-voltages in a residential Low Voltage (LV) network. This study is carried out on a radial distribution feeder modelled in MATLAB and simulations are run for 24 hour periods. A number of cases were tested...
Incentive-based demand response (IBDR) is an important category of demand response (DR) programs with large untapped potential, especially in the residential sector. Understanding customers elasticity is key to effective design of incentives. However due to limited information, price-based elasticity is needed in IBDR modeling as well. In this work, customer elasticity for an IBDR program is calculated...
The change rate of terminal voltage of a LiFePO4 battery is too small to be used to estimate state of charge (SOC) during discharging when the battery is within 10-80% SOC. A coulombic counting SOC estimation (Ah) method has the disadvantages of accumulated error and start point error. Therefore, in this paper the Extended Kalman filter (EKF) is used. The estimation accuracy of EKF deeply depends...
Hysteresis is an undesired phenomenon which degrades the positioning precision of a piezostage. Therefore, the hysteresis suppression is required for accurate micro/nanopositioning applications. This paper conducts a comparison study of three different approaches for the hysteresis modeling and suppression. Bouc-Wen model is a typical approach used to describe hysteresis. As a revised version, asymmetric...
This paper presents sensorless speed estimation scheme for Linear Induction Motor (LIM) using Cascaded MRAS Observer. Initially, LIM is represented by its state space model including the end effects. Next, the thrust due to end effect and the external load is modeled as a quadratic function of motor velocity. One of the parameters of the quadratic cost function is tuned according to adaptive laws,...
Distribution systems are being challenged by voltage fluctuation due to the increasing penetration of distributed photovoltaic generation. In this paper, a stochastic approach based on kernel density estimation is proposed to identify the optimal location for the PV plant installation in distribution systems so that the voltage deviation and network losses are minimized. In order to demonstrate the...
For a Li-ion battery based energy storage system, the state of energy is a key index for the energy management and operation optimization. In the actual Li-ion batteries based energy storage system in building environment, the varying load current will lead to the estimated battery's residual energy deviated from the real value. To solve this problem, an equivalent circuit model is presented for the...
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