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Everything posted by novacova
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Life is an experience on this planet, enjoy it while you’re here.
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What is amusing is noting the antisocial grown adults who are socially undeveloped that are easily offended by such minor things and resent others for having a disagreement or two or even a few. Whether it’s a forum nanny, user or abuser, it’s childish behavior that looks really silly. Reminder: You are grown adults and don’t take it so seriously.
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Spanish Power Outage - The Official Report
novacova replied to Crossy's topic in Alternative/Renewable Energy Forum
The scenario describes a cascading series of power system disturbances with multiple events triggering protocolized actions and equipment tripping. A concise analysis of the events and their implications, based on power system dynamics and standard protocols: 1. **Forced Oscillation (0.6 Hz, Badajoz PV Plant, N-1)**: A photovoltaic (PV) power plant in Badajoz introduces a forced oscillation at 0.6 Hz, likely due to control system issues or equipment malfunction. This triggers system-altering actions, including operating shunt reactors to manage reactive power and coupling lines to stabilize the grid. Schedule modifications indicate adjustments to generation or load to dampen oscillations. This is classified as an N-1 contingency (single element failure). 2. **Natural Oscillation (0.2 Hz, N-2)**: A lower-frequency natural oscillation at 0.2 Hz emerges, possibly due to system-wide resonance or insufficient damping. Further shunt reactor operations and line coupling are enacted, with additional schedule adjustments. This N-2 event suggests a second contingency compounding the initial disturbance. 3. **Reactive Power Absorption Failure (P.O. 7.4, N-3)**: Generation units under operating condition P.O. 7.4 (likely a specific grid code or protocol) fail to absorb required reactive power, exacerbating voltage control issues. This indicates non-compliance or equipment limitations, further stressing the system. 4. **RCW Generation Issues (N-4)**: Renewable (likely wind or solar, RCW = Renewable Control Wind or similar) generation units exhibit variations during active power regulation, impacting voltage control. Many units fail to meet grid obligations, suggesting control or communication issues, adding to system instability. 5. **Conventional Generation Failure (N-5)**: Requested conventional generation (e.g., thermal or gas units) to mitigate oscillations does not come online, likely due to delays, outages, or scheduling errors, leaving the system vulnerable. 6. **Generation Loss in Distribution (N-5)**: A minor generation loss (P < 1 MW) and significant self-consumption (435 MW) before 12:32:57 indicate distributed energy resources (e.g., small-scale PV or loads) are not contributing as expected, further straining the grid. 7–14. **Multiple Inappropriate Trippings (N-6 to N-10, N-12 to N-14)**: A series of inappropriate trippings occur across various generation types and locations: - Granada generation transformer (N-6). - Solar thermal and PV plants in Badajoz (N-7, N-8, N-14). - PV plants in Seville and Cáceres (N-9, N-10). - Three wind farms in Segovia and one wind farm plus a PV plant in Huelva (N-10, N-11). Many lack point-of-interconnection data, indicating missing telemetry or communication with the transmission system operator (TSO), which complicates system monitoring and control. 15. **CCGT Unit Tripping (Valencia, N-11)**: A combined-cycle gas turbine (CCGT) unit trips, removing a significant dispatchable power source, further reducing system stability. 16. **Load Shedding and Voltage Increase**: Underfrequency triggers load shedding of pumping units and other loads, reducing demand but causing an unintended increase in system voltage due to reduced reactive power absorption. 17. **HVDC Link Operation**: The HVDC link to France continues exporting 1,000 MW in constant power mode, unaffected by local disturbances. This may exacerbate local instability by prioritizing export over domestic stabilization. 18. **Nuclear Power Plant Tripping (N-12)**: A nuclear plant trips, a critical event given its large capacity and baseload role, significantly worsening the system’s stability and capacity margin. ### System Implications - **Oscillations**: The 0.6 Hz forced and 0.2 Hz natural oscillations suggest poorly damped inter-area or local modes, likely exacerbated by high renewable penetration and inadequate reactive power support. - **Cascading Failures**: The sequence of events (N-1 to N-12) indicates a cascading failure, where initial disturbances (PV-related oscillations) trigger widespread equipment trippings due to protection settings, lack of coordination, or missing telemetry. - **Reactive Power and Voltage Issues**: Repeated failure to manage reactive power (N-3, N-4, N-16) points to insufficient voltage control resources or non-compliance with grid codes. - **Data Gaps**: Missing point-of-interconnection data for multiple tripped units (N-7, N-8, N-10, N-11, N-14) highlights a critical issue in TSO visibility, hindering real-time response. - **Export Strain**: The HVDC link’s constant 1,000 MW export reduces local flexibility, potentially worsening underfrequency and stability issues. ### Recommended Actions 1. **Oscillation Damping**: Deploy power system stabilizers (PSS) on remaining conventional units and tune renewable controllers to dampen 0.2–0.6 Hz oscillations. 2. **Reactive Power Management**: Enforce grid code compliance for renewable units (P.O. 7.4) and activate additional reactive power resources (e.g., SVCs or synchronous condensers). 3. **Telemetry Improvement**: Address missing point-of-interconnection data by mandating real-time telemetry for all generators, especially renewables. 4. **Protection Coordination**: Review and adjust protection settings to prevent inappropriate trippings, particularly for PV, wind, and thermal units. 5. **Contingency Planning**: Enhance N-1 and N-2 contingency plans to prioritize local stability over exports, including dynamic HVDC control adjustments. 6. **Load and Generation Balance**: Restore conventional generation and adjust load shedding schemes to balance frequency and voltage. 7. **Post-Event Analysis**: Conduct a root cause analysis of the Badajoz PV oscillation and subsequent trippings to prevent recurrence. -
Fellers
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I thought it would get easier here at older age
novacova replied to Chinagmaiguy's topic in General Topics
Why work in a country where one may only be able to build a limited amount of wealth and assets and faced with a dead end? Work in your home country and accumulate wealth and assets, then retire and have your fun. -
Hall
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Report Phuket to Introduce Cannabis Zones Amid Growing Concerns
novacova replied to snoop1130's topic in Phuket News
On their stale weed beer breath. -
USA Trump to make decision on US involvement 'within two weeks'
novacova replied to Social Media's topic in World News
Impossible to predict the outcome either way. This may vary well blow the the Middle East and bring complete chaos in the region, or a revolutionary peace. Though if the Iranian regime survives then so will their nuclear ambitions to succeed in bringing uncertainty and perpetual conflicts. -
Also eating or eating too much before sleep has a higher chance of causing sleep apnea.
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Poll Should Thailand legalize brothels?
novacova replied to MalcolmB's topic in ASEAN NOW Community Pub
There plenty of “legal” brothels in TH. -
Architecture
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Data
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Pact
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Silver
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John
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No, not that sandwich at a western sit down in cm.
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Over
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Butt
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Yeah, all the neighbors have their security cams pointed at my house. They peek in the windows at night. They follow me wherever I head out to the local kad, the folks at the local kad are eye balling me the entire time I’m there. It’s a broad network of lurking and keeping tabs on me, I’m sure they have compiled a lot of detailed information and pass it on to those who are interested in other parts of the district.
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Illegal