High-voltage frequency converters successfully solve high-voltage problems by connecting components or units in series. Their common applications include various fans, pumps, compressors, and rolling mills in industries such as petrochemicals, municipal water supply, metallurgy, steel, and power energy.
High-voltage frequency converters come in a wide variety of types and can be classified in many ways. Based on the presence or absence of a DC component in the intermediate stage, they can be divided into AC-AC converters and AC-DC-AC converters; based on the nature of the DC component, they can be divided into current-type and voltage-type converters; based on the presence or absence of an intermediate low-voltage circuit, they can be divided into high-high frequency converters and high-low-high frequency converters; based on the number of output levels, they can be divided into two-level, three-level, five-level, and multi-level converters; based on voltage level and application, they can be divided into general-purpose converters and high-voltage converters; based on the clamping method, they can be divided into diode-clamped and capacitor-clamped converters, and so on.
The following precautions should be taken when using this type of frequency converter in high-temperature environments:
1. Carefully monitor and record all displayed parameters on the inverter's human-machine interface, and report any abnormalities immediately;
2. Carefully monitor and record the ambient temperature of the frequency converter room. The ambient temperature should be between -5℃ and 40℃. The temperature rise of the phase-shifting transformer must not exceed 130℃.
3. During periods of high summer temperatures, ensure adequate ventilation and heat dissipation at the inverter installation site. Ensure the surrounding air is free of excessive dust, acids, salts, corrosive gases, and explosive gases.
4. Summer is the rainy season, so precautions should be taken to prevent rainwater from entering the inverter (e.g., rainwater entering through the air duct outlet).
5. The filter screen on the inverter cabinet door should usually be cleaned once a week; if the working environment is dusty, the cleaning interval should be shortened according to the actual situation.
6. During normal operation of the frequency converter, a standard thickness A4 sheet of paper should be able to adhere firmly to the air inlet filter screen of the cabinet door;
7. The frequency converter room must be kept clean and tidy, and should be cleaned regularly according to the actual site conditions;
8. The frequency converter room must have good ventilation and lighting, and the ventilation and heat dissipation equipment (air conditioner, ventilation fan, etc.) must be in normal operation.
A frequency converter is a device that enables electric motors to operate at varying speeds, thereby achieving energy savings. Motors with rated voltages between 3kV and 10kV are conventionally called high-voltage motors; therefore, frequency converters developed for motors operating in high-voltage environments (3kV to 10kV) are generally called high-voltage frequency converters. Compared to low-voltage frequency converters, high-voltage frequency converters are suitable for variable frequency speed control of high-power wind power and water pumps, achieving significant energy savings.
