Breamlea Operations Group Progress Report 14 April 1995 Recent Developments: Mark McAllister re-built the brake power supply during March and it was reinstalled on Thursday 6th April. The microprocessor was turned on and the brake caliper adjusted. However the brake was left locked. Thus the W/G was able to track the wind, test the brake power supply under load and monitor the mains voltages, but not able to generate. The following day, Mr Vivian Ohis, an electrical engineer from CitiPower attended and performed a number of voltage, current and power tests as the windgenerator was powered-up. It ran well for about 5 minutes, and then the noise and power dips became apparent. I had arranged for PowerCor's breakdown crew to visit and they heard a fault on their power pole as soon as they got out of their truck. (Why didn't we hear it???). The fault was quickly traced to the white phase LV fusible link on the lower wooden cross-arm on the pole. It was replaced. The red & white links were cleaned and reset. The W/G was re-started and ran perfectly at 40 to 70 kW. It was left running. PowerCor Distribution Manager, Craig Hobbs was informed of developments and the fact that ATA has lost $2000 in 2 months due to their faulty equipment. CitiPOWER's Roger Lamb was also informed, and asked us to start invoicing CitiPOWER monthly, and they will START PAYING FOR OUR ELECTRICITY, while we get our verbal contract (8cents/kWh) negotiated formally and put on paper. A letter was sent to the Geelong Advertiser, highlighting the help received and informing re the open day on Easter Sunday. On Saturday 8th April I borrowed a grease gun from Gary Wileman and greased the generator bearings (18 pumps front, 12 pumps rear). Average power output in the 2 days to 6pm Sunday was about 19 kW. Approaches have been made to the Victorian Power Exchange and the Office of the Regulator-General to clarify whether we need to apply for a licence or apply for a licence exemption. We should have an answer next week. Most likely an exemption will be granted as we are under 1 MW installed capacity, and so small we are not even defined as an "Embedded Unit" under the VPX System Code. By the end of the financial year PowerCor is supposed to notify the Regulator-General of all Embedded Units connected to its grid, so we will need to formalise and document our relationship with PowerCor soon. Future Options: I am keen to "fine tune" the W/G to squeeze the maximum possible electric power out of it. Three easy and safe methods seem readily achievable without any significant risk to the integrity of the machine or its expected lifespan: 1. 220 or even 150 grade oil in the main gearbox. It currently contains 320 grade and becomes almost too hot to touch during prolonged high speed operation. Given the size of the gearbox, it might be dissipating up to 1kW or more of heat. Thinner oil will allow more power to the gen. and more electricity to be produced. If the generator operates an average of 12 hours/day this will mean another 6 kwH/day, or another $180/year worth of electricity. 2. Remove the fan from the rear of the generator. The gen. rotates at a fixed 1000 rpm whether it is producing 5 kW or 60 kW. It only gets hot when it is generating at high power. No cooling fan is needed below 15-20 kW. If the gen is enclosed in a cowling ducted to the rear grille, either natural wind flow or a thermostatically activated electric fan will keep the gen cool. More mechanical energy will be available for electric conversion. 3. A additional brake caliper can be fitted to the brake disc. It will need some control circuitry and sensors but will be applied when high speed generating averages 15 kW or less for 5 minutes (or when there are no peaks greater than 25 kW for 5 minutes). As it slows the blades, the generator will act like a motor for a few seconds, then disconnect. The high speed shaft will then rapidly decelerate to 750 rpm, which will be sensed by another inductive sensor on the gen shaft. The brake will then release as the low speed contactors switch in. This brake may operate frequently in certain wind conditions and it will need a brake-wear sensor which disables it at a predetermined state of wear. Late Note: On Saturday 8th April I borrowed a grease gun from the farm neighbour and greased the gen. bearings (18 pumps front, 12 pumps rear). Average power output in the 2 days to 6pm Sunday was about 19 kW. Approaches have been made to the Victorian Power Exchange and the Office of the Regulator-General to clarify whether we need to apply for a licence or apply for a licence exemption. We should have an answer next week. Most likely an exemption will be granted as we are under 1 MW installed capacity, and so small we are not even defined as an "Embedded Unit" under the VPX System Code. By the end of the financial year PowerCor is supposed to notify the Regulator-General of all Embedded Units connected to its grid, so we will need to formalise and document our relationship with PowerCor soon. M. Gunter