Novel method of benchmarking energetic efficiency of industrial systems
In actual economic environment, business sustainability requires high-efficiency technological processes. While Government and Utilities Demand Side Management (DSM) programs consider energy consumption (EUsed) as a whole, proposed method splits energy in 2 (two) specific components: Ideal energy (EIdeal) and Energy at Risk (E@R). Considering these two types of energy a Benchmark Energy Factor (BEF) can be defined. BEF compares the energy used by industrial system or processes (IS&P), Eused to the minimum energy required to accomplish the task at hand Eideal. Ideal energy (power) can be very accurate calculated by using adequate (well known) laws of physics chosen function of the work type performed by IS&P, therefore a solid (not empirical) reference for benchmarking system is available. That eliminates traditional variability that uses variable baselines as “best practice” or other criteria. Volatile comparative element across an industrial sector is replaced with a theoretical goal with a scientific set-up. BEF enables a new approach towards energy efficiency in industrial sector and help level the playing field for energy management. Proposed method promotes a sustainable and consistent approach making possible to determine accurately the (E@R) under variable material and environmental conditions making possible to manage the energy losses. The rating is then solely based on how close the true energy consumption within an IS&P gets to that ideal state. From economic standpoint, these sustainability concepts favor high-efficiency systems, as any energy-efficient system translates into higher effective productivity. Paper proposes a rating system model to describe the energy-efficiency for any IS&P independent of a comparison with others. BEF enables a reliable rating system model describing energetic efficiency of any IS&P that can be used by U.S. Department of Energy-Energy-Star Certification for Plants Program replacing existent benchmarking practice. Case study assessing IS&P by using (E@R) and (BEF) concepts with development of a new standard is presented.
System of Systems Strand Tilt Analysis Perspective on MediuMHigh Voltage Stator Bar and a Non-Destructive Testing Case Study
Stator copper bar is usually divided into several thin uniform strands, insulated from each other. This is done to reduce additional induced voltage due to convergence of magnetic flux from winding and rotor themselves. Flux density varies radially in density which causes different induced voltage strand to strand. To cancel out unbalanced strand voltage and minimize circulating current and resultant heating, strands are usually transposed. Transposition mechanism is fairly common, and is referred as roebelling. Manufacturing an ideal transposition is a difficult process. There is almost always some associated manufacturing defects present. Untreated issues like strand tilt leads to less utilization of material (less efficiency) & also issues like partial discharge leads to heating due to voids in the insulation. Nonconformance cost incur during the operation, if issues are not corrected. Paper presents the analysis with SoS (System of Systems) approach. In a better performing system (in this case electrical generator), each of the systems (strand, roebel coil and each phase winding) should collectively work to achieve the target of overall system (i.e. more efficient generator system). There are some other issues which arises due to the strand misalignment, e.g. void in the insulation, partial discharge and slot induced eddy voltage change and are discussed in the paper. Paper presents how important is it for system to work in coordination with other systems in order for the overall system to work efficiently. Paper also presents the complexity in evaluating strand tilt during stator coil manufacturing process. A unique solution of non-destructive testing to detect strand tilt is presented which provided excellent result. This is helpful to evaluate, how off the strand is tilted at any particular location on the generator coil.
Electrothermal Measurements of Bridgewires Used in Electroexplosive Devices
The bridgewire of an electroexplosive device is evaluated for its thermal response to impulse energy and to square-wave power. Thermal time constant and basic electrothermal parameters can be measured from the response. These parameters are useful in the study and characterization of electroexplosive devices.