An arc flash study is a critical analysis of your electrical system to evaluate arc flash hazards, enhance safety, ensure proper PPE selection, and maintain NFPA 70E compliance. An arc flash is a phenomenon where a flash-over of electric current leaves its intended path and travels through the air from one conductor to another, or to ground. The results are often violent and when a human is in close proximity to the arc flash, serious injury and even death can occur. Arc flash can be caused by many things including: Dust, Dropping tools, Accidental touching, Condensation, Material failure, Corrosion, Faulty Installation.
The factors to determine the severity of an arc flash injury are Proximity of the worker to the hazard, Temperature, fault current and Time for circuit to break. The main objective of an arc flash study is to identify and analyze high-risk arc flash areas in your electrical power system with greater flexibility by simulating and evaluating various mitigation methods in arc flash study.
The National Fire Protection Association (NFPA) has developed specific approach boundaries designed to protect employees while working on or near energized equipment. These boundaries are:
It is a well-known fact that the power system is not completely free from failures/faults. The key here is to mitigate the consequences during the event of faults. Damage of equipment during a fault can be reduced by quickly isolating the faulty portion from the rest of the healthy system. The objective of a relay coordination study is to determine optimum settings for protection devices such that the protection system isolates the minimum possible faulty portion at the earliest possible time to ensure a reliable power supply for the healthy system. The optimum settings ensure required sensitivity and selectivity that protect workers from harm as well. The software used for protection coordination study includes ETAP, DigSilent Powerfactory, PSCAD, and PSS/E. The relay coordination study involves protection devices from various manufacturers such as Siemens, ABB/Hitachi, GE, Schneider and so on.
A Short Circuit in a system is caused accidentally either due to insulation failure or a flashover of lines initiated by lightning or accidental faulty operation. This phenomenon results in the flow of heavy short circuit currents through the equipment, which may result in permanent damage to power system elements. Hence, it is important to ensure that the short circuit ratings of power system elements are adequate. In addition, the faulty parts need to be disconnected from the healthy power system network by means of circuit breakers, fuses and other protection devices to protect the power system from further damage. The software used for short circuit study are ETAP, DigSilent Powerfactory, PSS/E and so on.
A load flow study is the quintessential study as it aids in proper planning, design, and operation of generation, transmission, and distribution networks. The results of the study provide detailed insight into the steady-state performance under different operating conditions. Load flow is the basis for several other types of studies such as short-circuit, stability, motor starting, and harmonic, and protection studies as it brings out the initial steady-state behavior of the system.
Results of the study will be of great help in identifying the suitable operating conditions and in identifying abnormalities such as equipment overloading, excessive voltage drop, poor power factor, and power loss conditions. Most importantly, the analysis assists in the proper selection of continuous rating of equipment and in spotting out the need for voltage regulation devices and power factor correction devices.
This study can be carried out using ETAP, DIgSILENT Power Factory and PSS/E.
Electrical power systems are highly nonlinear and dynamic in nature: circuit breakers are closing and opening, faults are being cleared, generation is varying in response to load demand and the power systems are subjected to atmospheric disturbances like lightning. Thus, the electromagnetic and electromechanical energy is constantly being redistributed in the power systems among the system components. These energy exchanges cannot take place instantaneously but take some time period, which brings about a transient state. The energy status of the sources can also undergo changes and may subject the system to higher stresses resulting from increased currents and voltages.
In past days, system stability was regarded as a problem of electric utility engineers, but the future is moving towards a deregulated power system. This leads to the emergence of small independent power producers (IPPs) and co-generation (co-gen) companies where they produce power for industrial and commercial facilities by installing local generation units. Hence, a stability study is an area of interest in power system studies from the perspective of both utility and IPP/co-gen companies.
Stability is the concern of the power system behaviour when subjected to a transient disturbance, whether the disturbance may be small or large. It is the property of a power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbance. Transient Stability involves the study of the power system following a major disturbance where the synchronous alternator’s power (load) angle changes due to sudden acceleration of the rotor shaft.
Harmonic studies are normally performed to determine harmonic distortion levels and filtering requirements within a facility and to evaluate if harmonic voltages and currents are at acceptable levels. The recent development in technology is leading to high penetration of non-linear loads into the power systems. These non-linear loads lead to power quality problems in the power system. The characteristic harmonic emissions of these non-linear equipment must be identified, studied and rectified with corrective measures to save on power consumption costs and meet utility standards. This is where a power quality study becomes imperative, as it can be critical in reducing facility downtime and enhancing productivity.
With the growing proliferation of nonlinear loads in commercial buildings and industrial plants, which might become 30% to 50% of the total load, the effects of harmonics within the system and their impact on the utility and neighbouring loads need to be examined before any penalty is levied, equipment is damaged, or production is lost.
According to the IEEE 3002.8-2018, the outcome of this study is to design a new facility or power system, where the load-flow, power factor compensation, and harmonic analyses are considered as one integrated study to determine how to meet the reactive power demands and harmonic performance limits.
Our team has certified professional engineers to analyse the harmonics in the system and give technical solutions to various problems. We work closely with clients for the harmonic analysis study and recommend solutions for industrial & commercial facilities.
A grid compliance study is crucial for ensuring the reliability and stability of power systems. By adhering to relevant grid code compliance and standards, you can prevent issues such as voltage instability, power quality problems, and system failures. At Power Projects, we offer comprehensive assessments for various power systems, including renewable energy sources like solar power, wind energy, battery energy storage systems (BESS), hybrid systems (wind + solar + BESS), and generating stations. We utilize advanced power system simulation tools such as PSS/E, PSCAD, and DIgSILENT PowerFactory to ensure your system meets all necessary standards and performs optimally.
Motor acceleration studies are performed on industrial and large commercial systems where large motors can have unwanted consequences on the performance of the system and surrounding equipment. The starting current of most AC motors is several times (5 to 7 times) the normal full rated load current when starting from full line voltage. These large current requirements can result in nuisance tripping of protection breakers, excessive running currents, a drop in terminal voltage, triggering of under-voltage relays, low starting torques resulting in a failure to start, and stalling of other running motors connected to the power system. The impacts will be even more severe as the industry shifts towards energy-efficient motors where the starting current is as high as 10 to 12 times the full load current.
The ultimate objective of motor acceleration studies is to check whether a motor can successfully start or not, considering different operating conditions like starting the motor with a base load, starting the motor in the absence of the grid (only generator ON condition), and ensuring the system operates within the prescribed voltage limit during the starting transients. Both static and dynamic motor studies can be carried out; however, more detailed information like motor and dynamic load models are required to perform the dynamic acceleration study. Ideally, a motor-starting study should be conducted before a large motor is purchased so that the motor can be installed with confidence that its life and application performance will be satisfactory. A static acceleration study is preferred at this stage due to the non-availability of detailed information.