This tool ensures your Inverter-Based Resource (IBR) model is interconnection-ready. It is an advanced automation module built in EMTP®. Developed for Generation Owners (GOs), system operators (ISO, TSO), and consultants, E-Interconnect drastically simplifies the complex, time-consuming process of running Model Quality Tests (MQT) and conformity assessments required for grid connection. More information here: https://www.emtp.com/products/modules/e-interconnect – Willy Nzale, Henry Gras

EMTP® recorded the 26th of November 2025, showing the newly released E-interconnect tool.

Faults within a transmission system can greatly impact the capability for power transfer. Isolating a fault by removing the line from service can further diminish the power transfer capacity, compromising the system`s stability margin. Single-phase-to-ground faults, which are the most frequent, can be effectively isolated by taking only the affected phase out of service, while keeping the remaining two phases active. This approach, referred to as single-pole switching (SPS), permits the line to carry two-thirds of its power and preserve synchronization between the sources at both ends of the line, However, it presents distinct challenges. In a long line, a small AC current can still sustain even after the breakers open. This current is called the secondary arc current and it is due to electromagnetic coupling between the phase conductors. If the breaker pole is reclosed before this current extinguishes, the fault will reoccur, leading to unsuccessful reclosure. The aim of this work is to identify the key factors that significantly influence the secondary arc current and to evaluate different methods to reduce its amplitude. For successful reclosure, the circuit breaker`s dead time must be longer than the secondary arc`s extinction time. This study models the secondary arc using the EMTP program to simulate its interaction with the transmission system and estimate the necessary dead time for the circuit breaker. The study analyzes the self-extinguishment of the secondary arc by monitoring its magnitude and the recovery voltage using EMTP. It concludes with recommendations for reducing the secondary arc current and determining the minimum dead time required for the successful reclosure of a 380KV transmission line.

The implementation of distributed generation sources with islanding microgrid capabilities can introduce new challenges for engineers integrating new large generators to existing power systems. The generator interconnection transformer winding configuration and the generator winding pitch greatly impacts the flow of circulating currents and can result in unexpected generator heating, as well as high grounding resistor operating temperatures. This presentation presents a case study of the flow of 3rd order harmonic currents in a microgrid power system, and how EMTP was used to design equipment modifications necessary to reduce the current. A review of generators and how they can lead to 3rd order harmonic current generatio, along with additional options for correcting this condition will be presented.

Since 2022, the National Electric Coordinator in Chile has requested standardization of the dynamic models of the power plants or parks connected to the National Electrical System (SEN). As a company (EEMT), we have participated in the development of dynamic models for various wind and photovoltaic parks, carrying out a series of EMT homologations, both for equivalent and complete models. This involves analyzing their operation and validating them through records. Once this process is completed, it is possible to conduct tests and systemic verifications on the model, performing different short circuits and analyzing the LVRT. Thanks to the development and homologations of these models, in their complete and equivalent stages, different analyses can be carried out where electromagnetic phenomena exist for complete models, while with the equivalent models analyses can be carried out in a delimited area, generating faults and comparing them with real cases that have occurred. Within the framework of this conference, EEMT wants to present what the development of the homologation of these models has meant, the results that have been obtained in their different stages, and the usage that can be given to them for the performance of different analyses. On the other hand, as a consulting firm, we have been developing our own model of the Chilean National Electrical System based on various studies and based on the experience we have acquired as a leading consulting in EMT models. With the progress of homologations and the development of EMT models, it is expected that in the future there will be a systemic Database of the SEN that contains a greater number of aggregated models and that reliably allows for a large scale systemic analysis, such as, failures in the 500 kV transmission line, among other phenomena.

In this hydroelectric generation project, connection is established in a 500 kV system, which includes series compensation. A comprehensive TRV analysis was conducted to evaluate the existing circuit breakers. Based on this analysis, it was determined that implementing opening resistors is necessary to mitigate the adverse effects of TRV and ensure compliance with Peruvian electrical regulations.

This presentation will focus on a specific issue of bipolar HVDC lines with a dedicated metallic return (DMR). DMR is insulated to a lower level than the pole and its insulators are shorter. One event, for example, pole-to-ground-fault will cause a fault on both the pole insulation and the DMR insulation simultaneously because the DMR insulation fault will be supported by the DC current and will turn into a DC arc. To ensure independent pole operation, these types of events should be avoided or, if the DMR does flashover, to extinguish the fault as soon as possible. This is phenomena are presented and how different solutions are tested with EMTP software to protect the DMR.

This is a presentation on lightning overvoltage analyses for a 500/220 kV substation. Highlights: An interesting application case where the electrical distance between the surge arrester and transformer was quite long, requiring us to check the adequacy of the surge arrester. Proper selection of lightning parameters in line with CIGRE TB063 (updated in 2021). We can provide some easy-to-use recommendations for lightning waveform modeling. Modeling of substation apparatus, including some brief guidelines and critical points not to miss.

Shunt compensation reactors, deployed in long AC transmission lines, serve to mitigate overvoltages induced by capacitive charging under light load conditions. However, these reactors can introduce operational challenges, notably sustained overvoltages due to zero sequence resonance. Such resonance occurs in unbalanced conditions, often stemming from circuit breaker malfunctions that result in one- or two-phase disconnections. The zero-sequence resonance is triggered between shunt reactors and phase capacitance in disconnected phases. The overvoltage caused by this resonance can lead to equipment damage. The overvoltage caused by this resonance can lead to equipment damage.
The presentation will cover:
• Zero Sequence Resonance: Background on the phenomenon and resulting sustained overvoltages.

This presentation shows the acceptance tests performed on a wind power plant modeled using the WECC model. The plant cosistes of 121 turbines, each with a capacity of 0.85 MW, operating at 60 Hz. These turbines are connected to the 34.5 kV medium voltage collector system via 121 step-up transformers. The wind power plant is linked to the 320 kV network through a 230/34.5 kV 125 MVA main facility transformer. Other network components, such as collector cables and wind turbine step-up transformers, have also been represented by their equivalents. The model was developed and validated using two commercial tools – EMTP® and PSS®E. Simulations and analysis were performed to validate a group of acceptance tests required by the local utility. This presentation will focus on the modelling process, analysis and results obtained using EMTP®. The results obtained from the EMTP® and PSS®E are compared and discussed.

This presentation examines the impact of high DER penetration, particularly PV systems, on EPDS protection reliability. Instead of concentrating DERs in specific nodes, they are distributed along an unbalanced feeder with single-phase and three-phase PV systems. Various fault types, including impedance faults, were analyzed using the IEEE 34-node test feeder in EMTP-RV. Three scenarios were considered: (i) without DERs, (ii) 50% DER penetration with protection set by rated load, and (iii) 50% DER penetration with protection set by conductor capacity. Results showed reduced feeder relay currents for three-phase and phase-to-phase faults and significant decreases for phase-to-ground faults with impedance, leading to relay blindness and delayed protection operation. These insights support utilities in adapting EPDS protection systems for DER integration.

The Delta-connected STATCOM is regarded as the most advantageous topology for STATCOMs based on the Modular Multilevel Converter (MMC) technology. Embedding energy storage devices into the MMCs has gained significant research interest in recent years. This presentation focuses on modeling of MMC-based Delta-STATCOMs with embedded energy storage. A flexible modeling approach is proposed, which allows easy interfacing of various converter models with various energy storage device models. Four commonly used types of MMC models are applied to STATCOM modeling: detailed, detailed equivalent, arm equivalent, and average value. Supercapacitors and batteries are used as energy storage devices. Dynamic performances of the models are compared in transient simulation cases using EMTP.

This chapter presents some analysis of the modeling techniques used to evaluate the effects of electromagnetic interference phenomena that could occur when metallic pipelines are placed close to high-voltage power lines. The electric and magnetic fields produced by overhead power lines could perturb the normal operation of the metallic pipelines through induced currents and voltages. These perturbations could be dangerous for both pipeline operating personnel (as electrical hazard) and pipeline structural integrity (due to accelerated electrochemical corrosion phenomena). The chapter depicts the electromagnetic coupling mechanisms behind the abovementioned interference phenomena and how the induced voltages could be evaluated. A parametric analysis is showcased to highlight the influence of various geometrical and electrical parameters.

In this presentation three single-core cables with 630 mm2 copper conductors and lead sheathed cores, being in trefoil touching formation, are simulated through EMTP® and evaluated against experimental measurements. Both solid- and single-point sheath bonding configurations are considered. The standing voltages and circulating currents induced in the metallic sheaths are measured and compared against EMTP®. Positive-sequence impedance and loss results are also considered. As demonstrated, significantly better agreement between theoretical and experimental results occur when proximity effects are considered in EMTP®.

EHV cables have higher capacitance and a larger current, which increases the possibility of overvoltage occurrences during the charging. A 400kV EHV cable experienced a long-duration overvoltage incident that damaged the Lightning Arrestor. The incident was analyzed using EMTP®, and mitigation methods for cable charging were proposed. The EMTP simulation and site relay measurements matched closely. The presentation will share the analysis results and mitigation methods.

This presentation will focus on a specific issue of bipolar HVDC lines with a dedicated metallic return (DMR). DMR is insulated to a lower level than the pole and its insulators are shorter. One event, for example, pole-to-ground-fault will cause a fault on both the pole insulation and the DMR insulation simultaneously because the DMR insulation fault will be supported by the DC current and will turn into a DC arc. To ensure independent pole operation, these types of events should be avoided or, if the DMR does flashover, to extinguish the fault as soon as possible. This is phenomena are presented and how different solutions are tested with EMTP software to protect the DMR.

Battery technology and power electronic converters have facilitated the widespread use of Electric Vehicles (EVs), resulting in reduced rotational inertia and frequency stability of the power system. To address this issue, grid frequency support must be provided through various methods, including the regulation of power exchange between the grid and grid-tied inverter. Virtual inertia can be obtained from the energy stored in the DC link capacitors of the grid-tied VSC and the battery charging points. Coordinated droop control strategies from the VSC and EV charging ports can provide frequency support to the grid during disturbances. This session will discuss the use of EMTP® simulations to develop coordinated droop control strategies for mitigating frequency stability issues.

In this presentation, different wideband transformer models will be presented: extended BCTRAN model and black-box model based on measurements of frequency-dependent admittance matrix. These models are validated using transferred overvoltages measured in high voltage laboratory. Afterwards, the results of the EMTP simulations of the lightning overvoltages are presented and compared to the onsite measurements at power transformer terminals.

To facilitate the integration of renewable energy, RTE must connect new substations where multiple onshore wind power plants are connected at a distribution voltage level. These substations can be connected to the transmission grid with long underground cables, which can lead to harmonic amplification issues. To compensate for the lack of data on the distribution level of wind generators, RTE developed generic harmonic models for conducting harmonic studies and sensitivity analysis. This presentation will focus on the wind farm models, sensitivity analysis models, and results related to understanding which parameters influence harmonic amplification factors.

The accurate modelling of underground cable systems and specifically of sheath bonding designs in system studies is very important. In this presentation different modelling issues regarding the calculation of sheath currents and voltages at power frequency in power cable systems is systematically investigated. Different bonding schemes are considered, i.e., single-point bonding, solid bonding and cross-bonding, and a parametric steady-state analysis is presented using EMTP®. The results of the investigations reveal some important issues regarding the accurate modelling of underground power cable systems.

In this work, the standard model for wind power generation systems based on the international standard IEC 61400-27-1 (Edition 2.0, 2020) was implemented in EMTP®. Its validation has been carried out in a test system with respect to a validated RMS model of a wind farm in Chile.

The study of the damage and protection of systems against EMP weapons is very critical, especially for military purposes. This paper discusses the coupling modes and damage mechanisms of intense electromagnetic pulses (EMP); the interference effect of EMP on ELV systems is simulated and analyzed using EMTP.

Synchronous generators are exposed to oscillatory stresses due to their proximity to statcom devices and other power electronics devices, such as FSCs, HVDC controllers, and STATCOMs, which generate sub-harmonic frequencies. The interaction between sub-harmonic frequency components and mechanical mass can lead to Sub-Synchronous Resonance (SSR), an unstable and dangerous condition that causes torsional oscillation in the turbine generator shaft. This can reduce machine life, cause fatigue and damage to the shaft, and even result in its breakage. To avoid this, SSR detection/protection should be installed in generator units close to series compensated transmission lines. Different SSR modes can occur depending on the network condition and degree of compensation provided. Comprehensive Torsional Vibration Monitoring & Analysis systems are expensive, but there are cost-effective solutions to sense sub-harmonic quantities reliably at low amplitudes based on desired magnitude of sub-synchronous voltage and/or current. The offered solutions are supported by simulations, studies, modeling, and detailed analysis carried out in EMTP®.

The study analyzes the technical feasibility of the BESS Grid Booster project in an EMT simulation environment. A detailed EMT model of the Chilean power system was developed for the main 500 and 220 kV transmission systems. Most of the dynamic models for VRE generators used the AVM models from the EMTP® library. The study also included critical FACTS devices and all series compensation in the main transmission lines.

Lightning is one of the main electric hazards a photovoltaic is subjected to. This is due to the large collection area of the plant itself and to the incoming electric lines connected to the plant. The main purpose of this paper is to investigate in what cases LV/MV step-up transformers of the PV farm must be protected against overvoltages after a potential lightning strike event. This paper stabilises the lightning assessment simulation process by implementing a computer-based model in EMTP® based on the real engineering design of a 9MW PV plant connected to a 23 kV distribution grid in Chile.