NULL

Today’s electric power distribution systems with development of distributed energy resources introduce variability, uncertainty, and opportunities to recruit diverse resources for grid services. Multiple resources on each feeder have more complex impacts on the circuit behavior that can be observed with voltage and current phase angle variations. Micro Phasor Measurement Units (μPMUs) take timesynchronized measurements of voltage, current and frequency that can tell grid operators what is happening, where, and when. This paper presents a new μPMUs power flow algorithm for complete observation of balanced radial distribution grid. This algorithm calculates all voltages in both high and low voltage buses, currents in all branches, line active and reactive power flow in all branches and total active and reactive power losses in the grid. This algorithm provides high quality data for distribution planners and operators, which will translate into better model accuracy and thus better results from distribution analysis tools. To test the validity of proposed algorithm, backward / forward sweep power flow program is developed and tested by ETAP software.

Today’s electric power distribution systems with development of distributed energy resources introduce variability, uncertainty, and opportunities to recruit diverse resources for grid services. Multiple resources on each feeder have more complex impacts on the circuit behavior that can be observed with voltage and current phase angle variations. Micro Phasor Measurement Units (μPMUs) take timesynchronized measurements of voltage, current and frequency that can tell grid operators what is happening, where, and when. This paper presents a new μPMUs power flow algorithm for complete observation of balanced radial distribution grid. This algorithm calculates all voltages in both high and low voltage buses, currents in all branches, line active and reactive power flow in all branches and total active and reactive power losses in the grid. This algorithm provides high quality data for distribution planners and operators, which will translate into better model accuracy and thus better results from distribution analysis tools. To test the validity of proposed algorithm, backward / forward sweep power flow program is developed and tested by ETAP software.

NULL

NULL

The smart distribution grids monitoring process refers to consistently collect data related to all distributed resources conditions. The dynamic nature of distribution grid systems makes the monitoring tools to be essential in utilizing different types of distributed resources and providing smart services to users. This paper gives a general overview about distribution grid monitoring system and its challenges, technologies, aspects, key components, and important requirements. Also, it sets the rules for optimum locations and the scenarios for loss observation units.

The smart distribution grids monitoring process refers to consistently collect data related to all distributed resources conditions. The dynamic nature of distribution grid systems makes the monitoring tools to be essential in utilizing different types of distributed resources and providing smart services to users. This paper gives a general overview about distribution grid monitoring system and its challenges, technologies, aspects, key components, and important requirements. Also, it sets the rules for optimum locations and the scenarios for loss observation units.

This study presents the test results of seven exterior beam-column joints with different longitudinal reinforcement details for the columns. The test program included a beam-column joint designed to serve as a control specimen, in which column reinforcement was continuous ribbed steel bars. The other six specimens were divided into two groups, three specimens for each group. In the first group, the longitudinal column reinforcement was detailed with well-confined lap-splice longitudinal bars: two specimens were reinforced with lap-splice deformed steel bars and the later was with lap-splice plain steel bars. The same reinforcement details were used for the second group but additional longitudinal basalt fiber reinforced polymer (BFRP) rebars were placed at the joint and extended to the upper and lower columns. The test results showed that splicing the longitudinal column reinforcement successfully reduced the contribution of the joint to the deformability of the beam-column joint. Furthermore, adding BFRP rebars to the beam-column joint could be applied as damage controllable bars reducing both the damage level at the serviceability state and the shear deformability of the joint up to failure. A sole strut resistant mechanism was realized by the joints of all test specimens detailed with lap-spliced longitudinal column reinforcement. Ultimately, the test results point to a probability to the renunciation of the ACI 318-11 requirements for splicing longitudinal column reinforcement at column mid-height.

This study presents the test results of seven exterior beam-column joints with different longitudinal reinforcement details for the columns. The test program included a beam-column joint designed to serve as a control specimen, in which column reinforcement was continuous ribbed steel bars. The other six specimens were divided into two groups, three specimens for each group. In the first group, the longitudinal column reinforcement was detailed with well-confined lap-splice longitudinal bars: two specimens were reinforced with lap-splice deformed steel bars and the later was with lap-splice plain steel bars. The same reinforcement details were used for the second group but additional longitudinal basalt fiber reinforced polymer (BFRP) rebars were placed at the joint and extended to the upper and lower columns. The test results showed that splicing the longitudinal column reinforcement successfully reduced the contribution of the joint to the deformability of the beam-column joint. Furthermore, adding BFRP rebars to the beam-column joint could be applied as damage controllable bars reducing both the damage level at the serviceability state and the shear deformability of the joint up to failure. A sole strut resistant mechanism was realized by the joints of all test specimens detailed with lap-spliced longitudinal column reinforcement. Ultimately, the test results point to a probability to the renunciation of the ACI 318-11 requirements for splicing longitudinal column reinforcement at column mid-height.

This study proposes both steel and fiber-reinforced polymer (FRP) composites as main reinforcement for modern reinforced concrete (RC) moment-resisting frame (MRF) structures. A detailed three-dimensional finite element model (3D FEM), which takes into account the material and geometric nonlinearity and the bond behavior of steel and glass FRP (GFRP) reinforcement, was created and validated against the available experimental results. 54 cases covering several combinations of steel-to-GFRP reinforcements and design scenarios (under and over reinforced design scenarios) were studied. The analysis results of steel-FRP reinforced concrete (SFRC) joints pointed to the ratio between the effective FRP reinforcement ratio and the balanced FRP reinforcement ratio (the normalized reinforcement ratio) as the main design tool that can be adopted to achieve a predefined seismic behavior. Moreover, a definition is given to the lower and upper limits of the normalized ratio. Design recommendations regarding the controllability of the serviceability state, the post-yielding state, the ultimate state, and the residual strength of SFRC joints through an appropriate design for the steel-to-FRP mixing ratio are drawn. Ultimately, a mechanical model describing the behavior of SFCR joints with different steel-to-FRP reinforcement ratios is introduced based on the general behaviors of the simulated joints.