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In the area of active power filtering, with an objective to reduce inverter capacity, the Series Hybrid Active Power Filter (SHAPF) has been taken into account increasingly. Existing method used for controlling SHAPF is either based on detecting source current harmonic or load voltage harmonics. Generalised Instantaneous Power Theory (GIPT) gives simple and direct method of defining power quantities under sinusoidal and non sinusoidal situations. The definition of GIPT is used to decompose voltage vector into different components, which represents different parts of the power quantity. The separated components of voltage vector are used to derive reference for SHAPF. This paper presents simulation study of SHAPF used for harmonic elimination, where the method used for calculating reference is based on GIPT. The mathematical formulation of proposed control scheme with its applications to SHAPF is presented. The validity of the proposed control scheme is verified by the simulation study. [ABSTRACT FROM AUTHOR]

In the area of active power filtering, the Series Hybrid Active Power Filter (SHAPF) has been taken into account increasingly. SHAPF helps improving power quality problems like voltage unbalance, sag and swell in addition to its main objective of mitigating voltage and current type harmonics. Existing control strategies for SHAPF are based on extracting either source current harmonics or load voltage harmonics and are valid for balanced sinusoidal source conditions. In this paper a novel control scheme for SHAPF, which is based on generalised instantaneous power theory is proposed. This control scheme is valid for balanced and unbalanced, sinusoidal and non-sinusoidal source conditions and is capable of balancing load voltage while mitigating voltage or current type harmonics. The mathematical formulation of proposed control scheme with its applications to SHAPF is presented. The validity of the proposed control scheme is verified by the simulation study. [ABSTRACT FROM PUBLISHER]

In the area of active power filtering, the Series Hybrid Active Power Filter (SHAPF) has been taken into account increasingly. Existing control strategies for SHAPF are based on extracting either source current harmonics or load voltage harmonics and are valid for balanced source and load conditions. In this paper a novel control scheme based on generalised instantaneous power theory for SHAPF is proposed. This control scheme is valid for balanced and unbalanced source conditions and is capable of balancing load voltage while mitigating supply current harmonics. The mathematical formulation of proposed control scheme with its applications to SHAPF is presented. The validity of the proposed control scheme is verified by the simulation study. [ABSTRACT FROM PUBLISHER]

In this paper generalized definition of instantaneous power quantity in the multiphase system under balanced sinusoidal, unbalanced sinusoidal and unbalanced non-sinusoidal supply condition is discussed. In the area of Active Power Line Conditioners (APLC), shunt APLC is widely used in practice. Many reference current generation methods are proposed by different researchers, but most of them work optimally with balanced and sinusoidal source voltage. This paper proposes a novel concept of decomposing the multiphase current vector into different components, which represents different components of the power quantity. The components of current corresponding to zero-sequence power, oscillating power and unwanted components of active power are separated using these definitions. The separated components of current vector are directly used to derive reference for shunt APLC. The mathematical formulation of proposed control scheme with its applications to Shunt APLC is presented. The validity of the proposed control scheme is verified by the simulation study. [ABSTRACT FROM PUBLISHER]

Under geometric algebra framework, generalized definition of instantaneous power quantity in the multiphase system without any co-ordinate transformation is possible. In the area of active power filtering, with an objective to reduce inverter capacity, the Series Hybrid Active Power Filter (SHAPF) has been taken into account increasingly. This paper proposes a novel concept of decomposing the multiphase voltage vector into different quantities that correspond to different components of the power quantity. The separated components of voltage vector are directly used to derive reference for SHAPF. The mathematical formulation of proposed control scheme with its applications to SHAPF is presented. The validity of the proposed control scheme is verified by the simulation study. [ABSTRACT FROM PUBLISHER]

In this paper, we describe the use of phase-invariant complex wavelet filters, coupled to a training process involving a small, high-quality training dataset, to build an image segmentation system capable of performing in very low signal-to-noise, and under conditions of strong object-background contrast change. The three main components of our approach are: i) a patch-based feature description of local phase-invariant orientation fields; ii) a priori ground-truth data; iii) a machine learning method, such as Multilayer Perceptron (MLP) or kernel-based Support Vector Machine (SVM), to build an accurate classifier that is customised to the segmentation problem. A key feature of the approach is that it may be easily retrained and is, therefore, more adaptable to different imaging modalities. A representation of phase-invariant local image orientation using geometric algebra is first introduced; this is important to the patch-based approach. The quality of our trained systems is then assessed using Receiver Operating Characteristic (ROC) curves in two different biomedical applications: the human retinal vessel-bed in colour fundus images from the publicly available DRIVE database, and the rabbit endothelial cell boundaries of thoracic aorta microscopy images. [ABSTRACT FROM PUBLISHER]

This paper presents generalized definition of instantaneous power quantity in the multiphase system. This definition is presented without any co-ordinate transformation and is valid under sinusoidal and non-sinusoidal situations. In the area of Active Power Line Conditioners (APLC), shunt APLC is widely used in practice. This paper proposes a novel concept of decomposing the multiphase current vector into different components, which represents different components of the power quantity. The separated components of current vector are directly used to derive reference for shunt APLC. The mathematical formulation of proposed control scheme with its applications to Shunt APLC is presented. The validity of the proposed control scheme is verified by the simulation study. In simulation study applications of shunt APLC for harmonic elimination, reactive power compensation and load balancing are presented. [ABSTRACT FROM PUBLISHER]

Geometric algebra has been successfully extended to signal processing, feature extraction and pattern recognition, for example Clifford SVM, Clifford neural network, Clifford Fourier transform. But the two-dimensional visual pattern recognition research based on geometric algebra representation principle is still limited. We proposed a theory based on geometric algebra that generates the class field using the triangular method. The values of the geometric product by triangle geometry determine the types of samples tested. The test results of IRIS data set prove our idea, the recognition rate of 98%. [ABSTRACT FROM PUBLISHER]

We will present a fundamental solution of the constructive interference-problem of waves in two dimensions (also known as fringe patterns). Such problems are known from quantum physics and optics. In case of two one-dimensional waves with same frequency but different phases and different amplitudes, the solution of their resulting superposition or interference is well known. We will generalize this solution to two dimensions. In case of two dimensions the waves can not only be described by their phases, amplitudes and frequencies, also geometric properties pop up since in two dimensions an infinite number of additional degrees of freedom exists. The wave equations will be given in a traditional Clifford-valued tensor form. We will solve this problem in a hybrid matrix geometric algebra setting by mapping the traditional tensor expressions to Clifford numbers in conformal space. This Clifford number representation of two-dimensional waves can be used to solve the interference-problem linearly. Future work will consist of the generalization from 2D to multi-dimensional waves. [ABSTRACT FROM AUTHOR]

In 1D signal processing local energy and phase can be determined by the analytic signal. Local energy, phase and orientation of 2D signals can be analyzed by the monogenic signal for all i(ntrinsic)1D signals in an rotational invariant way by the generalized Hilbert transform. In order to analyze both i1D and i2D signals in one framework the main idea of this contribution is to lift up 2D signals to the higher dimensional conformal space in which the original signal can be analyzed with more degrees of freedom by the generalized Hilbert transform on the unit sphere. An appropriate embedding of 2D signals on the unit sphere results in an extended feature space spanned by local energy, phase, orientation/direction and curvature. In contrast to classical differential geometry, local curvature can now be determined by the generalized Hilbert transform in monogenic scale space without any derivatives. [ABSTRACT FROM AUTHOR]