Control of a pump device

Abstract

A method of controlling a pump device for discharging fluid, wherein the method comprises the steps of providing a heat portion adapted to be thermally coupled to the fluid to allow heat transfer there between when the fluid is at or above a certain level; monitoring a temperature parameter reflecting a temperature of the heat portion, the temperature parameter including a temperature value of the temperature of the heat portion; calculating a cooling rate value (CRV), the calculation including a comparison between at least two temperature values measured at different times; performing a pumping operation analysis including a comparison between a present cooling rate value (CRV) and a reference cooling rate value (ref), the reference cooling rate value representing a specific cooling rate of the heat portion; and initiating pumping operation to discharge the fluid if the cooling rate value is equal to or exceeds the reference cooling rate value.

Description

TECHNICAL FIELD OF THE INVENTION[0001]The invention relates to the field of methods for controlling a pump device for discharging fluid. The invention furthermore relates to the field of devices for controlling a pump device for discharging fluid.TECHNICAL BACKGROUND[0002]Pump devices for discharging fluid are used in a large number of applications, for example discharging fluid from fluid tanks or discharging excess fluid from construction sites or sewage pipes. Such pump devices may be of the submersible type, i.e. that the pump device is able to be at least partly submersed in the fluid which the pump device is adapted to discharge. In some applications, e.g. where the fluid level varies, it may be desirable that the pumping operation of the pump device is automatically controlled. For example, it may be desirable to control when the pump device is to be turned on or turned off depending on the fluid level or the variation thereof. Moreover, it may also be desirable to control th...

AI Technical Summary

Benefits of technology

The patent describes a method for accurately measuring the cooling rate of a heat portion in a pumping device. The method involves heating the heat portion to a specific temperature and measuring the temperature difference between the heat portion and the fluid. The heat portion can be actively or passively heated to ensure a sufficient temperature difference for accurate cooling rate measurement. The method also includes steps to account for changes in the surrounding temperature and to repeat the heating step if the temperature difference is not large enough. The invention can be used in various pumping devices to accurately measure the cooling rate and mitigate the influence of noise and numerical problems.

Problems solved by technology

Waiting a predetermined time before restarting the pump may be problematic due to the risk of flooding if the fluid level would increase rapidly during the predetermined time when the pump is stopped.

This problem could be partly alleviated by choosing a very short predetermined time, but on the other hand this would result in an excessive amount of unnecessary starts and operation resulting in wear to the pump.

Waiting until the temperature has decreased to a predetermined level before restarting the pump may result in similar problems, i.e. the risk of flooding if the temperature limit is set to a too low value or unnecessary starts and dry operation if the temperature limit is set to a too high value.

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