Overheat protection method for mining explosion-proof water-cooled frequency converter without flow sensor

Abstract

The invention relates to an overheat protection method for a mining explosion-proof water-cooled frequency converter without a flow sensor. The overheat protection method comprises the following steps: determining a temperature monitoring point referred by adopting the method by utilizing a thermal simulation technology or a thermal imaging experiment; adopting a BP neural network regression method to obtain a general prediction model; adopting a Softmax algorithm to accurately distinguish three working condition types of light load, heavy load and full load of the frequency converter; determining a flow prediction coefficient according to a classification result of the Softmax algorithm, performing temperature rise conversion, and substituting the flow prediction coefficient into the general prediction model to realize intelligent prediction of the flow of the water-cooling radiator under the current working condition and temperature rise; monitoring and recording the flow change of the water-cooling radiator in real time, and judging whether the system is in a safe working state. On the premise that a flow sensor is not used, high universality and intelligence are achieved, the requirements of engineering practice for simplifying system composition, reducing system cost, enhancing system reliability and the like are met, and the method is more suitable for working in an underground severe environment.

Description

Technical field: [0001] The invention relates to the technical field of sensorless intelligent prediction protection, in particular to an overheat protection method for a mine-used explosion-proof water-cooled frequency converter based on a flow sensorless method. Background technique: [0002] Water-cooled radiators are widely used in the cooling and heat dissipation of high-power mining explosion-proof inverters due to the high specific heat capacity of the coolant, high heat transfer coefficient, strong heat exchange capacity, and compact structure, small size, low cost, and high integration. . The performance of the water-cooled radiator is determined by the external input conditions. It is necessary to ensure the stability of the coolant circulation and sufficient coolant flow. Otherwise, the junction temperature of the high-power switching devices such as the rectifier module and the inverter module will be too high, or even overheated and fail. . Therefore, in order...

AI Technical Summary

Problems solved by technology

The existing problems are: the coal mine environment is complex and harsh, the flow sensor is prone to mechanical damage when it works for a long time, it is easily affected by electromagnetic interference and signal distortion, and the intrinsically safe flow sensor itself is expensive, and the communication and control equipment associated with it Complicated, difficult to maintain and replace, and there is also the problem of invalidation of the safety standard qualification

Images