patient help sheet - amazon s3...cause of sciatica. blood stagnation can affect the soft tissue of...

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CIRED Workshop - Ljubljana, 7-8 June 2018 Paper 0056 Paper No 0056 Page 1 / 4 ADVANCED ISLANDING DETECTION IN GRID INTERACTIVE MICROGRIDS Hannu LAAKSONEN Petri HOVILA Kimmo KAUHANIEMI, Katja SIRVIÖ ABB Oy – Finland University of Vaasa – Finland [email protected] [email protected] ABSTRACT In the future active network management and protection solutions have to enable utilization of intended island operation as well as active control and utilization flexibilities during normal and islanded operation of grid interactive microgrids. In this paper, combined islanding detection schemes for both MV and LV network connected distributed generation units during normal grid-connected operation are studied. Utilization of active network management functionality at MV level enables to control the reactive power unbalance continuously in order to ensure reliable islanding detection without non-detection zone. Combined scheme also prevents maloperations due to other disturbances. INTRODUCTION In the future, active utilization of controllable, flexible, distributed energy resources, DER, like distributed generation, energy storages, controllable loads/demand response, intelligent charging of electric vehicles will be in key role to enable more resilient power system. In addition, new cost-efficient, reliable, standardized and redundant solutions for future resilient power system must utilize possibilities of advanced ICT technologies (like wireless 5G and cloud servers with smart big data- analytics) and have cyber-security integrated in all solutions. Electricity distribution network areas with DER, i.e. FlexZones [1] or nested, grid interactive microgrids could be seen as resilient power system building-blocks. Intelligent and coordinated use of microgrids’ flexibilities between distribution and transmission system operators (DSOs and TSOs) for different technical services enables realization of improved local and system-wide grid resiliency in the future during normal grid interactive operation mode. During transmission or distribution network downtimes due to storms, natural disasters or external attacks (physical or cyber) microgrid with flexibilities can still continue electricity supply to customers in islanded operation mode. Grid-code compatible, combined islanding detection schemes (e.g. high-speed communication based transfer trip through optical fibre / wireless 5G, like IEC 61850- based GOOSE or routable R-GOOSE message & fault detection/direction + voltage vector shift, VVS) (Fig. 1) are needed in the future. With resilient combined scheme maloperation due to other network events can be avoided, non-detection zone (NDZ) can be minimized, prioritization issues with DG unit grid code requirements can be avoided and ENTSO-E RfG requirement (not only status position detection) can be fulfilled. Utilization of active network management (ANM) functionality at MV level enables to control the reactive power unbalance Qunb continuously in order to ensure islanding detection of the passive method (like VVS with sensitive settings) in the combined scheme without NDZ (Fig. 1). Realization of future-proof and grid code compatible schemes requires studies regarding dependencies between protection, islanding detection and ANM functionalities. [1]-[7] Figure 1. a) Combined islanding detection scheme, b) grid code compatible ANM scheme able to fulfill multiple targets simultaneously (see Fig. 2) and c) Dependencies between network status, protection, islanding detection & ANM functionalities and issues related to intended islanding operation prioritization. In this paper, combined islanding detection schemes (Fig. 1) for both MV and LV network connected DG units during grid-connected operation are studied by PSCAD simulations with model from Sundom Smart

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Page 1: Patient Help Sheet - Amazon S3...cause of sciatica. Blood stagnation can affect the soft tissue of the lumbar spine, hips and pelvis. This is what causes the muscles to spasm, then

© Acupuncture Media Works/AcuDownloads • www.acupuncturemediaworks.com • 0819

“Take care of your body. It’s the only place you have to live.” – Jim Rohn

Acupuncture for sciatica: Many studies have shown acupuncture is more effective at relieving the pain, numbness and tingling associated with sciatica than modern medicinal treatments. Acupuncture treatments can help to reprogram the muscles to stay in a relaxed position. Acupuncture treatments can also help treat sciatica by releasing natural painkillers like endorphins and enkephalins from the brain and neurologic system.

Acupuncture points for sciatica:Urinary bladder 23: This point is located on the lower back, halfway between the lowest ribs and the hip bone and on either side of the muscle group that runs right up the spine. This point reduces muscle tension and provides relief from low-back pain.

Urinary bladder 40: This point is located directly in the middle of the crease at the back of each knee. This point treats all the major pain sensations felt along the spine. It also helps to control muscle spasms, knee stiffness, arthritis, leg pain and it helps to dissipate excess heat trapped in the body.

Sciatica is the pain caused by pressure or irritation of the sciatic nerve, which runs from the lower back to the sole of the foot. The irritation

can lead to pain anywhere along the sciatic nerve, and it can also create a lack of muscle power to the legs and cause sensations in the legs, buttocks and low back to change. Current statistics show that up to 10 percent of the population between the ages of 25 to 45 are dealing with or have experienced sciatic pain.

The sciatic nerve is the largest nerve in the body. It consists of a large bundle of smaller nerves that begin in the low back region of the spine, travel down the buttocks and move through the leg. Symptoms of sciatica include radiating pain, numbness and tingling. Irritation of the sciatic nerve can be caused by muscle spasms, spinal disc compression or slipped spinal discs.

In traditional Chinese medical theory, blood stagnation is the most common cause of sciatica. Blood stagnation can affect the soft tissue of the lumbar spine, hips and pelvis. This is what causes the muscles to spasm, then creating extra tension that triggers the shooting pain associated with sciatica.

Traditional Chinese Medicine suggests several treatment modalities for managing sciatica.

Dietary and Lifestyle Recommendations for Sciatica: Adding potassium to your diet can help you heal from sciatica. Bananas, oranges, potatoes and spirulina are all good sources of potassium. Dark, leafy vegetables and legumes, such as black beans, kidney beans and soybeans are also beneficial when dealing with sciatica. Avoid foods that create dampness in the body, such as spicy, greasy or fried foods and dairy.

Incorporating daily exercise and stretching into your life can also help. The low back and lumbar spine may become weak if they are neglected, so sitting for long periods of time without getting up can be very detrimental. This also has a way of weakening the muscles of the lumbar area, which then can lead to slipped discs. Stretching and moving throughout the day, even after the pain has subsided, is vital to a healthy back.

Photo Credits: ©iStock.com/bluejayphoto, ©iStock.com/gilaxia

Patient Help Sheet Acupuncture for sciaticaHere are some tips that you can use to help balance and support

your health during this time. Please feel free to call me if you have further questions or concerns.

“Keep your vitality. A life without health is like a river without water.” - Maxime Lagace