Electric Control Cabinet Cooling Solution

Scheme Introduction

Intelligence is the trend of power grid development. With the gradual improvement and implementation of relevant technical standards, the proportion of intelligent substation projects is also increasing. In the construction of intelligent substation, outdoor cabinet is widely used. The intelligent control cabinet is installed outdoors, which can reduce the use of cables and optical cables, reduce the interference caused by long cables, reduce the floor area of the main control room, and facilitate the intelligent transformation of the old station. At the same time, because the outdoor cabinet is directly exposed to the air, in order to ensure the operation environment of the equipment installed in the cabinet, high requirements are put forward for the protection grade and environmental control of the outdoor cabinet. In recent years, with the vigorous promotion and construction of energy grid, the demand for intelligent equipment such as intelligent substation, intelligent control cabinet and intelligent terminal is increasing.

Let's discuss the thermal control solution of outdoor cabinet in power system. It is mainly divided into two aspects: humidity control and temperature control.

1. Humidity control

       For general electronic equipment, the relative humidity of 30% ~ 80% is more appropriate. When the relative humidity exceeds 80%, it will have an adverse impact on electronic equipment: reduce the performance of insulating materials, rust and mildew metal devices, etc. When the humidity further increases, condensation will be formed on the equipment surface under certain conditions, which will seriously affect the normal operation of the equipment. Under certain temperature conditions, the higher the relative humidity in the air, the closer the condensation temperature is to the ambient air temperature and the more likely condensation will occur.

     There are generally two ways of dehumidification: one is to reduce the relative humidity by increasing the ambient temperature and keeping the water vapor content unchanged; The second is to extract water vapor from the air through dehumidifiers and other equipment to directly reduce the content of water vapor. At this time, the inside and outside of the cabinet shall be completely isolated without air circulation. For the outdoor cabinet of power system, the heating dehumidification method is generally adopted to meet the operation requirements of the equipment in the cabinet: the heater is controlled by the temperature and humidity controller to achieve the purpose of dehumidification.

2. Temperature control

       From the current engineering application, two methods are mainly used: fan cooling and heat exchanger cooling. The temperature control equipment in both modes does not have refrigeration function, and the temperature control range depends on the external ambient temperature. If the equipment has high requirements for temperature, air conditioning refrigeration shall be considered.    

       Compared with the heat exchanger, the cabinet air conditioner can not only isolate the external harsh environment, but also adjust the temperature in the cabinet in a wider range. In addition to temperature and humidity, the operation of electronic equipment is also affected by external conditions such as wind, sand, dust and salt fog. In practical application, the heat dissipation method depends on the specific situation of the project.

The electric outdoor cabinet air conditioner developed by LANDKING perfectly solves the problems of temperature control and humidity control.

Application scenario：

Outdoor control cabinet applied in power industry. More project details, see power cabinet cooling in Project Cases section. 

Product feature：

• Standard electric heating function；

• Integrated cover design;

• Professional dehumidification design can effectively control the relative temperature of the application;

• Low noise, micro positive pressure design meets the requirements of power grid indicators;

• 4 ~ 20mA output ambient temperature and humidity signals;

• The temperature is adjustable between 18-50 degrees, which solves various disadvantages caused by ventilation and heat dissipation;

• The automatic evaporation function of condensate is selected to effectively solve the problem of condensate discharge;

• RS485 interface, support MODBUS protocol communication and realize remote monitoring function;

• It has the function of self starting when power is on, and provides a variety of alarm and protection functions;

• Support alarm dry contact output;

• Chinese and English LCD menu display is convenient for setting parameters and viewing alarm information;

• R134a environment-friendly refrigerant meets ROHS requirements;

• High reliability, 365 days / year, uninterrupted operation for more than 10 years;

• Full front maintenance, simple and convenient, reducing service costs;

• Strong corrosion resistance, IP55 protection.

• It can meet different certification needs of customers.