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Most Canadian remote communities are supplied electricity partly or wholly generated by diesel generators, which results in high electricity costs mostly due to the cost of transporting fuel to the remote locations. A large portion of the financial budget from the government or local community is allocated to cover the cost of diesel electricity generation. Renewable energy integration can substantially reduce the cost of electricity generation and greenhouse gases (GHGs) emissions in these remote communities. The annual solar photovoltaic (PV) potential for these northern arctic communities ranges from 850 to 1150 kWh/kWp; therefore, a significant portion of the community energy requirement can be supplied by the PV system. This article presents the impact of PV integration on the system’s annual performance and project economic aspects of small remote northern microgrids for integrating varying penetration levels of centralized PV systems. The modeling of a typical PV-diesel hybrid system considering the electrical performance, emissions, and economics of various generation sizes and control strategies has been addressed. The methodology presented in this article can help quantify the PV energy integration limit (without any spill/curtailment) and economic feasibility of new PV system integration in current arctic microgrids.

As modern grids shift towards renewable energy (RE), new challenges arise with higher penetration of inverter-based distributed energy resources (DER). The variability and intermittency of RE also pose significant challenges for grid operation. Therefore, DER standards are updated/revised with new grid support functions to ensure proper grid operation with higher penetration of renewable energy. This paper presents an assessment of the frequency-droop function from the recently revised IEEE 1547-2018 standard. The function is assessed using high-resolution solar photovoltaic (PV) system production data from commercial PV inverters of a 5 MW solar farm. Several issues with the current droop function implementation is discussed. In addition, PV energy curtailment with different settings of the droop function is also assessed. The results are presented using the datasets of five days with different levels of solar variability. The daily energy curtailment can be as high as 4.1% and 13.2% with IEEE 1547 and CSA C22.3 No. 9 standards respectively.

A model for interpolating irradiance data in space and time is developed using cloud motion vectors. It is tested using two networks of photodiodes in Eastern Canada that measure irradiance at time scales of milliseconds and spatial scales of tens of meters. The model captures network-average variability with skill scores of up to 86% compared to nearest neighbor interpolation. We provide case studies showing how to use this model to study inverter response to rapid irradiance fluctuations. We also use AC power measurements from an inverter collocated with one of the photodiode networks to benchmark our approach and the wavelet variability model.

Canadian remote arctic communities are mostly supplied electricity by diesel generators. The electricity price in these communities is high due mostly to the transportation cost of the diesel fuel to these remote locations. A large portion of the financial budget from the government or local community is allocated to cover the electricity cost. Diesel power plants are also major emitters of greenhouse gases (GHGs). The annual solar photovoltaic (PV) potential in the Canadian arctic region ranges from 850 to 1150 kWh/kWp. Therefore, a significant portion of the community energy requirement can be supplied by PV systems thus reducing diesel fuel consumption and associated GHG emissions. This paper presents the impact of PV integration on the system annual energy performance at various levels of PV penetration. The modelling of a typical small arctic PV-Diesel hybrid microgrid is addressed with the specifications of a small representative community. The PV utilization analysis establishes the low PV penetration regime up to 40% of peak load. Then two technical alternatives are presented that allow medium PV penetration up to 70% of peak load with associated PV energy contribution up to 23% of the community energy requirement.

The vast majority of the 300 Canadian off-grid communities rely heavily on diesel-fuel generators as their source of electricity. In northern communities, the annual photovoltaic (PV) potential ranges from 850 to 1150 kWh/kWp. Therefore, there is an opportunity for these communities to decrease their dependency on diesel fuel by integrating more PV to supply a portion of their electricity demand. Currently, remote Canadian microgrid models are not available to conduct studies that involves integrating PV as alternative solution. The availability of a simulation model with field data will allow for the opportunity to study renewable energy integration as well as hosting capacity with smart grid technologies such as advanced inverter functions and demand-side management. This paper addresses the need to reduce the diesel consumption of Jean-Marie River First Nation; a remote community in the Northwest Territories of Canada. A digital microgrid model of the community's power grid was developed using OpenDSS and Matlab. The model was then validated with field data measured using an advanced metering infrastructure. The validated model was used to conduct renewable energy (RE) integration study and establish a range of maximum allowable PV capacity on the power grid based on voltage limits. Later, advanced inverter functions were applied to mitigate voltage violations resulting from the RE integration thus further increasing the PV integration limit or hosting capacity of the microgrid.

In 2016, 1.2 GW of photovoltaic (PV) power tripped off in California during the “Blue Cut Fire” when PV inverters miscalculated the grid frequency during a line-to-line fault. In response, the 2018 edition of the IEEE 1547 interconnection standard was updated to mandate distributed energy resource (DER) devices “ride-through” voltage phase angle changes that appear during faults. This new requirement is designed to ensure bulk-system stability is not impacted by emergent DER misbehaviors triggered by local fault events. Transitory DER behaviors under phase changes may still significantly impact grid operations, so it is necessary to quantify the DER response to both balanced and unbalanced voltage phase angle shifts. To achieve this, two PV inverters were subjected to balanced and unbalanced phase jump changes defined in the IEEE 1547.1-2020 test protocol to validate compliance to IEEE 1547. Experimental results show that one DER inverter was compliant to IEEE 1547 and its “momentary cessation” behavior produced stable power system response. However, the other PV inverter failed the IEEE 1547.1 compliance test and tripped off during some of the phase jump experiments.

Grid codes around the world are requiring grid-support functions (GSFs) and standardized interoperability interfaces for distributed energy resources (DERs) to address the rapid increase of renewable energy. However, these new GSFs need to be assessed to ensure the desired power and communication capabilities exist in the field. The IEEE 1547.1 standard outlines the conformance test procedures for DER devices and is currently undergoing a major revision to align it with IEEE 1547–2018. Once it is published (anticipated in mid-2020), GSFs in commercial PV inverters in USA and Canada will be certified to the IEEE 1547.1 conformance test procedures. Several international research laboratories are collaborating to develop a versatile open-source DER testing platform that performs automated testing of DER devices. This community of laboratories is developing open-source IEEE Std. 1547.1 test scripts to lower barriers to DER vendor internal equipment evaluations, ease product compliance testing at certification laboratories, and provide research institutions a tool to study DER behaviors. In this work, test scripts were used for test verification of GSFs, including limit active power, constant reactive power, active power-reactive power (watt-var), and prioritization of GSF response for several DER devices. Sample test results for these DER GSFs and test protocol recommendations are presented in this paper.

With the rapid increase in renewable energy integration in the electric grid, grid codes around the world are getting updated with requirements of grid support functions (GSFs) for the distributed energy resources (DERs). The Canadian interconnection standard CSA C22.3 No. 9 recently underwent revision and recently completed the public review process. This revised standard included advanced GSFs for DER systems and the test procedures (mostly referring to IEEE 1547.1 or UL 1741 SA) for assessing these DER GSFs. Two commercial solar/photovoltaic (PV) smart inverters were tested at the CanmetENERGY inverter test facility following the test procedures from UL 1741 SA and using the parameters from CSA C22.3 No.9. This paper presents the important aspects of the test procedure while doing standard compliance tests for the selected GSFs. Test results, issues requiring future consideration and comments are presented in this paper.

The high penetration of distributed energy resources (DERs) (especially PV) presents a number of technical challenges for power system operation; one of them being overvoltage. To better manage the grid operation, the interconnection standards around the world are including requirement of grid support functions (GSFs) for these DERs. The recently updated Canadian interconnection standard, CSA C22.3 No. 9 also included advanced GSFs requirements for these DERs. This paper investigates the impact of high PV penetration on the voltage profile of Canadian suburban residential neighborhood. The initial base case is established with the consideration of the legacy PV inverter (unity power factor operation) in 216 houses in which case voltage violation is observed in the network. Then the voltage profile of the neighborhood is compared for three separate scenarios with different GSFs; fixed power factor, Volt-Var and Volt-Watt. Each GSF is configured according to the CSA C22.3 No. 9 standard. These functions can mitigate/reduce the overvoltage issues in different proportions, e.g., voltage violation does not occur for fixed power factor operation. The impact of these GSFs on the customer PV production (active power) and the loading of the network component are also analyzed in this paper.

The irradiance at ground level mostly fluctuates due to cloud coverage. As clouds are moving toward a certain direction, the cardinal orientation of photovoitaic arrays affects the variability of the output power, and thus the impact on the electric power grid. This paper presents a new methodology with a circular layout for irradiance monitoring units to assess the solar variability in different directions of any site based on cloud speed-direction trend and directional variability reduction. The proposed methodology is used to assess the directional variability for a site at Varennes, QC, Canada using 1 year of measured data. The cloud speed direction is studied in order to observe any trend from a month-to-month and from an hour-to-hour. Overall the cloud direction has a trend of West to East direction, especially during the winter months. The variability reduction for each axis is estimated using the variability index (VI). The largest VI reduction is observed close to the cloud direction axis.

Several international research laboratories are collaborating under a Smart Grid International Research Facility Network (SIRFN) project to develop certification procedures for advanced distributed energy resources (DER). To effectively evaluate interoperability and grid-support functionality in DER equipment, test permutations across the full range of modes and parameters are required. It is impractical to complete these experiments manually so the project team is working to develop a software tool, associated abstraction layers, and hardware drivers to execute the experiments autonomously using the same opensource test logic. This software can then be programmed to complete interoperable DER certification experiments at DER vendor facilities, certification laboratories, or research institutions. By sharing the codebase with all institutions, barriers to adoption steadily decrease. To demonstrate the approach, Underwriters Laboratories 1741 Supplement A volt-var and specified power factor test results from multiple laboratories are presented and compared.

This paper presents an overview of the minimal complexity level requirement for modeling generic grid-interactive inverter to conduct power flow, protection, stability and power quality studies. For each functional, control or protection block of the inverter system, it describes the appropriate level of complexity needed to perform each of the power system studies. This work serves as a foundation for the development of an inverter modeling toolbox to facilitate power system studies in renewable energy projects. It intends to address the need of utilities to have access to adequate inverter models to perform accurate integration impact studies of photovoltaic or inverter-based wind projects.