Vacuum on demand: Control system improves milking process efficiency, reliability and performance
Dairy processing is considered one of the most energy intensive sectors in the food industry. What’s more, over 80 per cent of total energy use on a dairy farm is accounted for by milk cooling, water heating and vacuum pumping. Systems integrator Technidrive has developed a vacuum on demand control system to improve reliability and energy efficiency of vacuum pumping on dairy farms.
Often described as the heart of the milking system, vacuum pumps remove air from the system creating a vacuum. The vacuum pump sucks air out of the system, regulated by a mechanical valve. In traditional fixed speed systems using a motor and a pump, the vacuum pump works at full capacity regardless of whether this is necessary.
For example, a fixed speed system for a 1,600 litre pump, will produce 1,600 litres of vacuum a minute, even if only half of this is necessary at that time. This not only wastes energy, but also results in unnecessary wear on the pump. In fact, this is such a problem that government incentives are being created to encourage innovation and efficiency improvements to technology used in the sector.
In addition to the environmental issues surrounding inefficient equipment, Technidrive’s engineers also encountered several further challenging factors associated with this dairy application. Many farms in rural areas operate on poor power supplies, such as single phase 230v but also three phase 400v. Voltage dips and phase imbalance can cause unwanted harmonics, high current spikes, nuisance tripping and poor control on systems.
“Four or five years ago, Technidrive was working with a customer who had asked us to provide an inverter for a robot milking system supplied by DeLaval,” explains Andrew Ritchie, technical sales manager at Technidrive. “They were trying to run the robot off a single-phase supply. However, they didn’t have enough energy to run all equipment at once. We put together a control system to solve this issue and soon discovered that this wasn’t an isolated case.”
This enquiry led Technidrive’s engineers to develop an efficient variable speed system that could be completely flexible for integration with all manufacturer’s equipment. Importantly, it could also eliminate harmonics to be suitable for use alongside electronic equipment such as tags and flow meters.
The system can be retrofitted onto existing vacuum pumps or integrated into new systems. Delivering energy savings between 35 and 55 per cent compared to fixed speed systems, the system also offers reliable vacuum pressure, significant reduction in noise from reduced pump speeds, increased pump life and reduced pump servicing requirements.
Having installed over 600 systems in dairy farms across the UK and Ireland, the technology is designed to be integrated with minimum interference and footprint. In fact, the control panel can be installed in just three to four hours. Regardless of the original equipment manufacturer (OEM), the system is compatible with 95 per cent of pumps.
Depending on the system purchased there are multiple features to reduce the risk of total shutdown such as manual overrides of sensors. If a sensor malfunctions, an override switch kicks in and relies on the valve system as a fixed speed system. In some cases, Technidrive has also developed dual systems. In these solutions two drives with two controllers are used in the same panel. By using two smaller solutions, in the event of any failure in the pump system, it can still run at half capacity.
“We have numerous Technivac systems throughout Northern Ireland and a couple in the south of Ireland,” said Andrew Dunn owner of Northern Dairy Services Premier dealership, covering Northern Ireland for Waikato milking system. “As long as the dairy farmer ensures his electrician makes sure all power requirements are exactly what is required to run the drives, the system is very easy and quick to fit.” For more information visit www.technidrive.co.uk.