Kalkitech PowerApps is a Power System Engineering Software that features some of the most advanced analysis tools for transmission, distribution and industrial power systems. Kalkitech offers comprehensive services in order for our customers to fully benefit from the PowerApps applications in their specific IT/Engineering environment and to address their engineering/operational analysis needs. The services offered include engineering studies, assistance to integration and comprehensive training.
PowerApps is an integrated Power Systems Analysis Software & Simulation package that includes the Graphic User Interface, Data Base Manager, and Electrical Equipment Parameter Estimation for creating the network one-line diagram and associated database. PowerApps offers both graphical and tabular data entry modes, user-preferred single-line diagram drawing options and advanced facilities for reporting, plotting and customizing the simulation reports. The design of PowerApps recognizes the fact that there is no memory restriction in present day computers. Consequently, PowerApps has no built in dimensioned variables and the needed memory for analysis of any system is allocated dynamically during execution time.
PowerApps calculation engine is the backend of PowerApps that does calculations needed for various power system / electrical system analysis/design and studies. Given below is a summary of the calculation modules available with PowerApps engine
- Single/3 phase load flow analysis
- Short circuit calculations / Conventional/ IEC 60909 / ANSI
- Transient Stability Analysis [Large Signal Performance]
- Dynamic Stability Analysis [Small Signal Performance]
- Static Voltage Stability Analysis
- Relay Coordination[Overcurrent phase/earth/instantaneous/distance]
- Motor Starting Studies/Motor Acceleration Studies
- Optimal Power Flow/Economic dispatch/Reactive power optimization
- Harmonic analysis/Filter Design/Impedance Scan
- Short Term Load Forecast
- Long Term Energy and Demand Forecast
- Power System Stabilizer Applications
- Contingency Ranking and Evaluation
- Network Topology Processor
- Observability analysis
- Static State Estimation
- Ground mat design
The ease of use of PowerApps can be understood from the multitude of options it provides the user with. Some of the key ones are listed below.
- Supports multiple drawing pages, of any standard sizes and orientation
- Provides unrestricted number of Undo and Redo facilities for the drawing
- Page Zoom facility
- Data view, Symbol view - Tree structure
- Graphical display of equipment grounding
- Standard drawing symbols like, bus, nodes, breakers, relays, lines, bus-sections, transformers (2 winding, 3 winding), neutral impedances [resistances, reactances, NGT’s], CT’s, PT’s, generators, motors, constant power loads, harmonic current injections, SVC’s, fuses, shunt capacitors, shunt reactors, series capacitors, series reactors, HVDC links HVDC converters, Harmonic Filters, FACTS devices, Mutually coupled lines etc.,
- Interactive data entry through symbols for various analysis
- Execution of analysis modules using the GUI and report generation, report manager, Tabular reports, Reports on Single Line Diagrams, Plot form reports [X-Y plots, linear – linear plots, linear – log plots, log – log plots, Bar charts]
- Selection of single or multiple elements
- Customizable font types, styles and colors
- Copy and paste facility for single or multiple elements to reduce drawing effort
- Hide and Show of protective device
- Single database for all study cases and analysis. Single report database file for all analysis and study cases for easier maintenance.
- Customizable display of rating and results
- Automatic display of energized and de-energized elements using dynamic continuity check.
- Single or Batch mode execution of all study cases and report generations
- Solution for networks with multiple network islands
- Combination of XY Plots and One Line Diagram portions for printing and report purposes
- Standard Library Facilities for equipments for technical data and technical performance curves [cables, overhead conductors, motors, transformers, generators, generator controls and relays.
- Built in network topology Processor in the analysis modules that construct equivalent network mathematical model based on the breaker/switch statuses, blow fuses, outage of elements etc.
- Built in calculator for MVA, MW, MVAr, KV, AMP, short circuit impedance, etc.,
- Facilities for Base Case Study and derived case studies [where derived cases reflect changes in parameters of the base case]
The following minimum hardware/software configurations are recommended and higher configurations can be used wherever possible.
- Microsoft Windows XP Professional, Version 2002, Service Pack 3 or above
- Any Intel or AMD x86 processor (≥ 1.0 G Hz), At least 128 MB RAM
The software solution by KALKITECH will be loaded in each individual PC’s and can have local or server based hardware locks depending on choice of licensing. KALKITECH’s software solutions can use any standard printer, plotter available on the LAN.
PowerGUI is a general purpose single line diagram tool for construction of single line diagrams, taking data inputs for various power system analysis modules, execution and report generation.
Power Foundation Classes
Power Foundation Classes [PFC] is a collection of C++ classes for various electrical equipments, mathematical functions and power system analysis algorithms. PowerApps software is built using these class library functions. These functions may be provided to end users/industries/academics on license basis for academic/research/industrial/consulting applications
PowerGraph is a post processing utility used for XY plots of types, linear-linear, linear-log, log-linear, log-log. Typical examples of usage are transient stability plots, Motor starting studies, Driving point impedance plots in Harmonic studies.
PowerTCC is a time current characteristic modeling tool that draws the Time Current Characteristics (TCC) of protective devices and shows the discrimination in relay operating times. User can modify relay settings and can achieve better coordination between protective devices. The utility can also plot TCC’s for the PowerApps relay coordination module.
PowerMath is a collection of generic mathematical functions used to develop the power system analysis software modules. These include matrix routines, sparse matrix techniques, curve fitting techniques, statistical analysis tools, optimization techniques, numerical integration routines and so on. There are specific routines for both complex numbers and Real numbers. The methods are general and are applicable to any field. These modules can be provided to end users on license basis with specific documentation and support via email.
PowerUI is a general purpose user interface with context sensitive help for preparing the database for power system studies using PowerApps. The database structure is generalized and can be used for any other specific applications where similar user interface requirements exist.
Kalkitech PowerApps comes with a host of analytical modules that are essential for all power system studies. These includes power flow studies, short circuit studies , transient stability studies, state estimation studies, relay coordination studies, harmonic analysis studies.
Power Flow / Load Flow Solution Module
Power flow calculations provide active and reactive power flows and bus voltage magnitude and their phase angle at all the buses for a specified power system and operating conditions. These values are subject to the regulating capability of generators, synchronous condensers, static var compensators, HVDC controls, FACTS controllers, tap changing under-load transformers and specified net interchange between individual operating systems (utilities). This information is essential for the continuous evaluation of the current performance of a power system and for analyzing the effectiveness of alternative plans for system expansion to meet increased load demand. These analyses require the calculation of numerous power flow cases for both normal, and emergency (contingency) operating conditions. PowerApps provides the following key features:
- Gauss-Seidel/Newton –Raphson/Fast-Decoupled Models.
- Load flow solution of multiple-islanded systems. The solution is available for each of the islands having a reference (slack) node. The reference node is automatically identified by the algorithm as the largest generator node in each island.
- Shunt compensations, series compensations, phase shifters, transformer taps.
- No limits on the number of study cases and related reports in a single execution of the program
Short Circuit Analysis
Short circuit calculations provide currents and voltages on a power system during fault conditions. This information is required to design an adequate protective relaying system and to determine interrupting requirements for circuit breakers at each switching location. Fault conditions can be balanced/unbalanced shunt faults or series (open conductor) faults. Often information about contributions to a fault from rotating machines such as synchronous machines and large motors would be required as a function of time to determine making and breaking requirements. Fault calculations may consider or ignore pre-fault power flow conditions. PowerApps supports the following key features:
- Fault levels for asymmetrical and symmetrical faults including bolted faults.
- ANSI/IEEE standards.
- IEC standards including 363 and 909.
- G74 British standard, a computer algorithm based standard for IEC 909 standard.
- IEC 909 standard specified multiplication factors based on hand calculation procedures and simplifying assumptions.
Transient Stability Analysis
The recovery of a power system subjected to a severe large disturbance is of interest to system planners and operators. Typically the system must be designed and operated in such a way that a specified number of credible contingencies do not result in failure of quality and continuity of power supply to the loads. This calls for accurate calculation of the system dynamic behavior, which includes the dynamic characteristics of the rotating machines, generator controls, static var compensators, loads, protective systems and other controls. Transient stability analysis can be used for dynamic analysis over time periods from few seconds to few minutes. Kalkitech PowerApps supports the following key features:
- Transient models of excitation systems, turbine governors, static-var compensators and power system stabilizers.
- Load shedding / islanded operation.
- Transient stability analysis of multiple-islanded systems with solution for each of the islands.
- Choice of generator models -From simple classical generators with constant voltage behind transient reactance to modeling detailed synchronous machines with variable voltages behind sub-transient reactances.
- Standard IEEE excitation system models and turbine and governor models.
- Commercial excitation models and governor models.
Voltage Stability Studies
An important issue in the real time system operation, monitoring and control exercise is to check whether the system is sufficiently working within the stability limits and whether the system has sufficient stability margins.
For static or steady state operating point, it is determined by the power transfer limits as determined by the static voltage stability analysis. For normal operating conditions where system is subjected to small power impacts, these limits may be defined by the small signal stability considerations. PowerApps supports the following key features:
- Ability to perform bus-level voltage and steady-state stability calculations to identify critical buses.
- Can provide system-wide voltage and steady-state stability calculations for a broad range of user-specified single and multiple contingency events.
- PowerApps is capable of determining the loading limits imposed by voltage stability under the steady-state conditions.
- Compute both the total system MW loading and the MW schedule for each generator and tie-line import for a state that would correspond to the security margin.
- Contingency cases can be configured as an input that can be combined into single or multiple event scenarios.
- Can be used in sizing the reactive power compensation devices required at relevant buses to prevent voltage collapse.
- Can calculate the maximum transfer of power between buses before voltage collapse point
Relay Co-ordination and Protection Settings
Protective relays are to be designed to isolate the faulted portion of the system at the earliest with minimum system disruption. When the relays meant to protect specific equipments, transmission/distribution lines/feeders or zones do not operate backup relays must act to isolate the fault providing sufficient time discrimination for the operation of the primary relays. The relays must also be able to discriminate between faulted conditions, normal operating conditions and abnormal operating conditions. PowerApps supports the following key features:
- Coordination with maximum load current.
- Coordination with fuse characteristics.
- Coordination with maximum motor starting current and time.
- Coordination with transformer inrush current.
- Coordination with primary-back up pairs.
- Coordination with thermal withstand capabilities ([I2]t = K characteristics).
- Coordination with safe stall limits for Motors.
Motor Starting Studies
Motor starting studies can help in the selection of best method for motor starting, motor design, and system design so as to minimize the impact of motor starting. Analysis of motor starting methods can be performed by both static and dynamic simulation techniques as follows. These techniques have their own conveniences, advantages and drawbacks. The result should be transient (dynamic) motor starting studies that reproduce observed (measured) motor starting conditions. Following are the key features supported by PowerApps:
- Load flow type solution with the perceived starting impedance of the motor modeled as part of network modeling
- Short circuit method type of calculations considering pre-fault short circuit conditions and using voltage drop calculations considering motor starting currents.
- Where accurate dynamic model of the motor electric circuit and load torque characteristics are available, dynamic model of the motor can be used in traditional transient stability algorithm to assess the impact of the motor starting.
Energy Management System Solutions
Kalkitech has the following functional modules readily available. These modules can be provided or integrated with an Existing SCADA/EMS system.
- Network Topology Processor
- Observability analysis
- Static State Estimation
- Contingency Ranking and Evaluation.
- Long and Short Term Load Forecast
Optimal Power Flow
OPF analysis module of PowerApps is based on the dual LP programming approach and has the following features:
- Newton - Raphson load flow for solution at an operating point.
- OPF solution of multiple - islanded systems. The solution is available for each of the islands having a reference (slack) node. The reference node is automatically identified by the algorithm as the largest generator node in each island.
- Choice of objectives for the OPF (Transmission loss minimization, Voltage Stability improvement, Removal of operating violations, Economic dispatch, ATC calculations).
- OPF control options are active power injections, reactive power injections, shunt compensations, series compensations, phase shifters, transformer taps.
- OPF sensitivity calculations with respect to the performance objective provides information for suitable location of shunt reactive power compensation and also identifies most effective controllers for optimization.
- No limits on the number of study cases and related reports in a single execution of the program.
- PowerApps supports a generic trend as well as generic regression model for bus load forecast.
- Historical data of the bus loads at a given time of the day can be stored in the database along with the other parameters such as temperature, type of day, rain fall, humidity, bus voltage and frequency etc..
- The results from bus load forecast can be used for off-line power system analysis as well as for on-line state estimation for pseudo measurements as needed. This can also be used for short term operational planning using economic dispatch and optimal power flow solution of PowerApps.
- The method of bus load forecast used in PowerApps is also applicable to the system wide load forecast
- State Estimator (SE) computes the static state of the system (voltage magnitude and phase angle) by monitoring available measurements.
- PowerApps State Estimator supports a variety of communication options such as OPC (automation for Process Control) or Shared Memory Interface for implementing data interchange with any kind of SCADA system.
- Highly accurate estimation of full system state that minimizes deviations from measurements
- Fast-converging non-linear optimization algorithms
- Observability test, inbuilt topology processor and bad data analysis
- State Estimator solution for multiple-islanded systems.
- Contingency evaluation studies typically refer to evaluation of network adequacy and security under credible network element outage conditions.
- Typically outage of important transmission lines, transformers, generating units are usually considered in the evaluation.
- The evaluation is carried out by using static as well as dynamic analytical tools such as load flow analysis and transient stability analysis.
- Real time control and monitoring solutions in energy control centers or energy management systems or load dispatch centers usually use an algorithm called contingency ranking algorithm to shortlist credible contingencies for real time evaluation and control of power systems.
- Often contingency ranking algorithm will use some approximate and fast load flow type algorithms from a list of contingencies and rank them in the decreasing order of severity.
- This ordered or ranked list will be considered for a detailed contingency evaluation to assess system security.
Harmonic Analysis and Filter Design
Harmonics in power systems can result in undesirable influence such as Capacitor heating/failure, Telephone interference, Rotating equipment heating, Relay mis-operation, Transformer heating, Switchgear failure, Fuse blowing. The main sources of harmonics in power system are static power converters, arc furnaces, discharge lighting and any other load that requires non-sinusoidal current. In order to limit the harmonic current propagation in to the network, harmonic filters are placed close to the source of the harmonic currents. Harmonic filters provide low impedance paths to harmonic currents and thus prevent them from flowing into the power network.
- Distortion Factor Calculations as per IEEE 519 Standard
- Impedance Frequency Scans to identify parallel and series resonance points and bus locations
- Modeling of harmonic sources and filters
- Modeling of all electric circuits as function of frequency
- Analysis using design data or field measurements
- Analysis for various network configurations, fault levels
General Features of PowerApps
- Multiple study cases of load flow/short circuit/stability/protection/and other analytical procedures cases for all the network islands in one single execution
- A single master database for all the study cases and outputs for easier maintenance of project database.
- Facilities for interactive single line diagram creation using a Windows based PowerGUI.
- Automatic network model construction based on breaker statuses using an inbuilt Network topology processor. The Network topology processor algorithm is suitable for real time/Offline simulation applications.
- Multiple study cases due to changes in breaker statuses, changes in load power specifications, changes in generator schedules, changes in transformer taps, changes in number circuits, changes in compensation are handled in single program execution without creating additional databases and the results are stored in the same single database for post processing (e.g. Report generation). All other analysis which needs load flow base case as input are automatically executed after each load flow base case (e.g. Transient stability analysis with different disturbance scenarios) and the results are stored for post processing.
- Derived study cases from any given study base case with necessary data changes.
- No in built restriction on system size or components. The size of the system can vary between the barest minimum to maximum permissible by the memory available in the computer.
- Multiple stability study cases on the same load flow base case, with different disturbance scenarios.
- Input data in the format of ASCII, Excel, Access databases.
- Object oriented programming approach with Power Foundation Classes (PFC) to build analytical algorithms. The concept is similar to using MFC for MS windows programming in VC++.
- Standard library facilities for all common electrical elements.
- Validated algorithms (documents) with standard bench mark examples.
Key References for PowerApps Implementation
Power Systems Division of Central Power Research Institute has used the PowerApps power system simulation software successfully for the following studies:
- Load Flow and Short Circuit Calculations of Raichur Thermal Power Plant, Network leading to relay coordination.
- Load Flow and Short circuit calculations (both conventional and G74 (IEC909) Standard) for Rourkela Steel Plant Renovation and Modernization schemes, and
- Load Flow and Energy Audit for Southern Power Distribution Company of Andhra Pradesh.
Download Link to Reference Certificate
PowerApps software was successfully used by Danway LLC for the following studies:
- Voltage Drop/Load Flow Studies
- Short Circuit Studies
- Motor Starting Studies
- Relay Coordination Studies
PowerApps software has been used in I.D.E.A for carrying out Power system studies. The recent projects carried out by I.D.E.A using PowerApps are given below:
- GMR International Airport, Hyderabad
- Essar Steel, Hazira
- Rourkela Steel Plant, through CPRI, Bangalore
- Elme Petro Chemicals Ltd, Nigeria
- Riddi Siddi gluco biols limited, Gokak
Power Engineering & Technology Consultants Pvt. Ltd. (POET) has used PowerApps to perform power system studies for industrial power projects for:
- Bio Mass Generator Project
- Wind Farm Project
- Breaker Failure Analysis
- Paper Mills
- Automobile Plant