Water cooling VFD is mainly composed of water-cooling air conditioning tank, phase shifter transformer, power cell cabinet, control cabinet and circulating pure water cooling cabinet (hereinafter referred to as water cooling cabinet), as shown in the picture:
1. Composition of Transformer cabinet
Transformer cabinet has two parts including the transformer tank and water-cooled air conditioning cabinet, as shown in figure 3, 4, phase shift of water-cooled air conditioning cabinet is used for cooling, the forced air cooling way to carry transformer heat to the air channel, concentrated collection hot air through the heat exchanger, then transfer the heat to the cooling water in the heat exchanger pipe, in order to cool it, the cooling wind after cold go back to the transformer tank, makes the temperature of the transformer enclosure to maintain in a certain range. At the same time, the cooling water in the heat exchanger pipe absorbs heat and flows out of the outlet and takes the heat away. The cooling water of heat exchanger pipes is below 33 ℃, so it keeps the indoor environment temperature of VFD below 40 ℃(heat exchanger outlet temperature), so as to guarantee the stability of the VFD running in the stable environment.
Cold source water flow pipe is equipped with instrumentation monitor parameters, accurate display of circulating water temperature, flow parameters;
There is air valve on the top of the heat exchanger and there is drainage valve on the bottom of the heat exchanger, which can drain the circulating water and prevent frostbite.
There are the temperature transmitters setting at the inlet position of the fan and the wind outlet position of heat exchanger respectively, which can monitor the operating environment of transformer in the real time.
There are PT100 temperature sensor in the primary side windings and side windings of the transformer, which can monitor the wind channel temperature of the transformer winding in real time.
2.Power cell cabinet
Power cell heat dissipation method: water cooling is the main method; air cooling is the auxiliary heat dissipation mode.
Programs and features
Cooling water pipe adopts the parallel access, ensure uniform flow distribution;
Independent power cell electrolytic capacitor cooling wind channel, capacitor operating temperature lower and has a longer life;
The power unit radiator adopts the vacuum brazing type water cooling radiator, the inlet and outlet of water cooling radiator use the double intercepting fast connector, which is very convenient for power cells replacement;
The main pipe of power cell cabinet is stainless steel pipe, and the junction between the power cell and the main pipe use the rubber hose, which can guarantee the insulation of the power cell.
3.Circulating water cooling unit
Cooling water driven by the main circulation pump, along the pipeline at a constant flow through the power cell heat sink, constantly take out the heat, after warming, cooling water go along the main pipe loop into the heat exchanger equipment for heat exchange; After cooling, cooling water backflow to the inlet of the main circulation pump, forming a closed loop cooling system. The system control module automatically adjusts the heat exchange rate according to the preset cooling water temperature value, thus controlling the water temperature accurately.
According to the different cooling capacity and the conditions of the site, the system can release heat into the environment by using water - water, water - wind and other secondary heat exchange forms.
Because of the VFD is run under the environment of high voltage, cooling water must have high resistivity, so in the main loop cooling circuit in parallel bypass deionized water treatment, a percentage of the cooling water flowing through the ion exchanger, continuously removing ion precipitation from equipment and piping. In order to keep the pressure of the pipeline constant and the flushing of the cooling water, and the volume change resulting from the temperature change of the buffer cooling water, the buffer tank and water filling device are set up in the system.
All parts of pipeline circuits adopt stainless steel material, which have a good anticorrosion sex;
The main circulating pump adopts redundant design and can be replaced and repaired online.
Independent deionized water treatment bypass device;
Independent PLC monitoring system can realize remote control.
It has comprehensive warning protection function. For example: leakage monitoring and alarm, condensate monitoring and control, water temperature control and water temperature alarm, water conductivity monitoring and alarm, etc.
4.The operating conditions
Due to the power cell cabinet of the water cooling VFD, in addition to the main electronic device on the cooling water plate, there are the electrolytic capacitor, connect copper platoon and other heating device in the power cell cabinet, which can generate heat, so the cooling fans are installed on the top of the power cell cabinet, it can take out the hot air to the environment, thus the water cooling VFD has to be installed in the air conditioning room. The air conditioning refrigerating capacity is 0.5% of the rated power of VFD.
VFD is Installed in the independent enclosed space, according to the frequency of the VFD equipped with cooling air conditioning. Air conditioning power selection formula:
P air conditioning = (P VFD (kVA) * 0.5%) / 2.5, unit is lmx.
On site provide 5-32℃ cooling water resource, the flow is related to the VFD capacity. If there is no cooling water supply, the secondary water cooling equipment can be providing when supply of the VFD.
The water circulation system of water cooling VFD includes two parts: internal water circulation system and external water circulation system. As shown in figure 2, the water circulation between plate heat exchanger and power cell in the water-cooling cabinet is called internal water circulation system, also called primary circulation; namely the constant pressure and flow velocity of the water cooling cabinet are continuously flowing through the plate heat exchanger for the heat exchange, after heat exchange, then it enter the power cells of VFD taking away heat, warmed water back to the inlet of the main circulation pump, by electric three-way valve regulating the flow into the plate heat exchanger, achieve accurate control the purpose of the cooling water temperature in the pure water cooling device. At the same time, some water will be exchanged by ion exchanger to meet the required deionized water.
The heat from the heat exchanger and plate heat exchanger in the water-cooled air conditioner is brought out by the continuous cooling source water outside. The water cycle is called the external water circulation system and the second cycle is called.
Scheme 1 Site provides the requirement external water
Scheme 2 Closed cooling tower
Working fluid (water) circulate in the coil of closed cooling tower, working fluid heat disperse in the water coil when it goes through the water coil. At the same time, the outside the air enter from the side air-inlet grille, it is perpendicular to the water flow direction, when it is flow water coil crosswise, a small part of the water evaporates and absorb heat, the hot humid air is being exhausted from the top of the cooling tower fan into the atmosphere. The rest of the water fall into the bottom of the water dish, recycle it to the water distribution system by the water pump, by pre-cooling packing it pour back into the coil.
Scheme 2 Precision cold water machine
Working principle of the system: the cooling system is mainly composed of compressor, condenser, expansion valve, plate heat exchanger, cooling fan, water tank, water pump, web of circulating pump, etc. On the one hand, cold water in water tank through a external water circulating pump circularly flow into the external water inlet pipe of the water cooling cabinet, flow back to the water tank after heat exchanged in the plate heat exchanger of the water cooling cabinet, to decrease the temperature of cooling water in the water cooling cabinet; on the other hand, the hot water flow back into the water tank, through the refrigeration system of refrigerant heat exchange, the plate heat exchanger exchange with the low temperature hot water, to reduce the temperature, so as to maintain the water tank in the cold water temperature; The high temperature refrigerant to reduce the temperature by cooling fan exchange with the surrounding environment.
Rated input voltage
50Hz / 60Hz (-10%~15%)
Cell-cascaded multilevel PWM
3-phase 380V AC
Input power factor
>0.98 inverter section; >0.96 including transformer
Output frequency range
0.01 Hz (0 Hz~80 Hz)
Instantaneous over-current protection
150% protects immediately (or customized)
120% 2 minutes; 150% instantaneous
Current limit protection
Two loops 4~20mA
Four loops 4~20mA
Modbus RTU built-in, Devicenet / Profibus /Ethernet IP optional
Acceleration and deceleration time
5s～1600s (load dependant)
Inputs and outputs
12 inputs /9 outputs (extendable)
-5 to +45 ℃
-40 to +70 ℃
< 95%, non-condensing
<1000m, when altitude is higher than 1000m, each 100 meter derates VFD by 1%
500VA / 1000VA Optional
Non-conductive, no causticity，＜6.5mg/dm３
RAL 7032 (or Customized)
External cooling water
Supplied by user / closed cooling tower (on request, not for free) / precision cold water machine (on request, not for free)
English / Russian / Spanish (Customized)
Sound level at 1 meter
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Hiconics Eco-energy Technology Co., Ltd.
Address：NO.3 Boxing 2nd Road,Economic and Technological Development Zone,Daxing District, 100176,Beijing, China
TEL：+86 10 5918 0185