At present, the variable speed regulation method of the air conditioning cold and hot water circulation pump has constant pressure difference control, fixed terminal pressure difference control, minimum resistance control and temperature difference control.
1. Constant pressure difference control: to make the supply and return water dry pipe pressure difference to maintain a constant control method. Supply and return water dry pipe pressure constant pump provided by the pump to maintain a constant, it is also known as the constant pressure control Ding Yangcheng control. This approach is: according to the static water collector and a water separator before and after the cold and hot water circulating pump of the poor control of cold and hot water circulation pump speed, the static pressure difference is always stable around the setting value.
2. Fixed terminal pressure control: to make the end (the most unfavorable) loop pressure to maintain a constant control method. This method is: according to the air-conditioning water system in the most unfavorable loop in the air conditioning equipment before and after the static pressure difference, control the speed of the cold and hot water circulation pump, so that the static pressure difference is always stable in the vicinity of the set value.
3. According to the minimum resistance control valve of each air conditioning air conditioning cold and hot water circulation system in the opening of the cold and hot water circulation pump speed control, the control valve has at least one open state in control method.
4. Temperature control: the supply and return water temperature difference of dry pipe to maintain a constant control method. When the load drops, such as flow rate remains unchanged, then the return water temperature decreased, the corresponding temperature difference becomes smaller, to keep the temperature constant, can reduce the pump speed by controlling the temperature controller and frequency converter. To reduce the water flow, decreasing the energy consumption of the pump speed to between three parties.
