外文翻译-基于西门子LOGO！控制的驼峰空压站风源监控设计

广西科技大学毕业设计外文翻译系 别 专 业 班 级 学 号 姓 名 指导教师 2013 年 5 月 16 日MM420 inverter energy-saving measures in the water supply system-Nanjing Hangda Yihang Technology Co., Ltd.Because the frequency conversion velocity modulation does not need to construct the tradition for the aqueous system for the aqueous system top digit water tank, the water tank, avoided two times polluting and reducing the construction investment, moreover designed reasonably can achieve the good energy conservation effect.In gives in the aqueous system, the constant speed pump only then in its highly effective section movement can guarantee the system normal work also does not have the energy dissipation.In the design, (this time current capacity is generally biggest by the pipe network most unfavorable situation, must lift is also biggest) takes the choice water pump unit the main basis, but when the pipe network current capacity reduces, the energy waste is inevitable, when also possibly creates the low current capacity in pipeline overpressure question.The water pump basis system current capacity real-time change realization stepless speed regulation movement, is solves above problem well, achieves one of energy conservation goal ways.The water pump velocity modulation may through the very many way realization, in which frequency conversion velocity modulation be the present ideal one kind.The frequency conversion velocity modulation is through will give on the aqueous system pipe network the pressure transmitter to carry on the sampling to the pipe network hydraulic pressure, transforms the pressure signal into the electrical signal, and delivers to the PID regulator and the user establishment value of pressure it carries on the comparison and the operation, finally will transform for the frequency control signal delivers to the frequency changer.The frequency changer basis transmits frequency control signal adjustment water pump electrical machinery supply frequency, thus realizes adjusts the water pump the rotational speed.May divide into two kinds according to the customer in actual use request frequency conversion velocity modulation for the aqueous system: The live pressure variable gives the aqueous system for the aqueous system and the constant pressure variable.The live pressure variable establishes for the aqueous system pressure transmitter in the service pipe net terminal, the PID regulator setting value the service flood peak value which needs for the pipe network terminal user.The system causes the pipe network terminal hydraulic pressure maintenance through the automatic control to be constant, causes the pipeline characteristic curve and system static lifting is invariable, but the water pump water outlet pressure changes along with the volume of diversion change according to the pipeline characteristic curve, therefore theoretically realized “the system to need how many, the unit provided how many”, could not because the volume of diversion reduced has unnecessary static lifting, the energy conservation effect was satisfied.But this is only one kind of ideal situation, also in the system only has the frequency conversion pump alone to work.Because the frequency conversion equipment quite is expensive, large-scale often uses the frequency conversion pump and the constant speed pump parallel operation way water supply for the aqueous system.Presently establishes a frequency conversion pump and a power frequency pump and the combined transport behavior example by the system in.When the pipe network current capacity reduces, needs to lift reduces correspondingly, the frequency conversion pump may through the deceleration movement realization.But also must reduce correspondingly for guarantee parallel unit normal work power frequency pump lifting, this only can through increase the current capacity realization, thus creates the water volume the dropout, also possibly causes the power frequency pump to leave the highly effective section work, namely has not achieved the true energy conservation the goal.Meets has above situation, may take following measure to improve its energy conservation effect:Gives the aqueous system regarding the small scale, may only suppose a frequency conversion pump, and causes the pump the highly effective area (its highly effective scope to move the time scope compared to power frequency pump to want as far as possible many including to appear the probability big operating point in a big way). Uses the multi-Taiwan pump velocity modulation movement, certainly, quite is expensive as a result of the frequency conversion speeder price, should overall evaluation its economic agent decide. When choice power frequency pump, should cause the system when the most disadvantageous spot work, the power frequency pump operating point approaches left side of as far as possible its highly effective area; If the most unfavorable situation appears the probability to be small, may enable it to deviate slightly the highly effective area, falls in the highly effective area left flank.Thus, when system lifting reduces, the power frequency pump still may in the highly effective area work. The constant pressure variable is located in the water pump unit water outlet for the aqueous system the pressure transmitter, is for the purpose of causing the water pump water outlet pressure maintenance to be constant, general hypothesis for most disadvantageous operating mode when the water pump water outlet needs the value of pressure.Still by a frequency conversion pump and a power frequency pump and combined transport behavior example.When the pipe network current capacity reduces, the frequency conversion pump through the deceleration movement, maintenance lifting invariable reduces the water discharge.Because the outlet pressure is invariable, the power frequency pumps out the water volume not to be able to change (i.e. movement operating mode invariably), still in highly effective area work, thus achieves the energy conservation goal.Needs to point out, the system needs when the current capacity changes small, the water pump water outlet pressure (still for the most unfavorable situation in system needs pressure) to be bigger than the pressure which the pipeline this time needs, thus still could cause static lifting to a certain extent the waste.Following two measures may improve its energy conservation effect: Enlarges the pipe network suitably the caliber, causes the pipeline characteristic curve to hasten gently, but this can increase the pipe network the disposable investment, needs and the energy conservation effect makes the comprehensive economical comparison.When choice power frequency pump causes each pump the operating point to fall as far as possible on the highly effective area.For aqueous system when water used trough (for example at night), in the system the water consumption is very small, even achieved the zero current capacity, is called “the micro current capacity”.In this case, if depends upon at the highly effective area great current capacity scope movement water pump maintains the system pressure, not only buckle water pump life, moreover the efficiency is low, cannot achieve the energy conservation the goal.Theoretically, the frequency conversion pump current capacity may approach in the highly effective scope in the zero, but in fact the water pump rotational speed not impossible unlimited to reduce, only depends on the frequency conversion pump to be competent the micro current capacity operating mode with difficulty toward the dealings.The actual project uses generally when the system additionally builds the small current capacity power frequency auxiliary pump, small current capacity facilities and so on frequency conversion auxiliary pump, barometric pressure pot maintain the micro current capacity the system pressure.To the different system micro current capacity question should the special details concrete analysis, and carries on the overall evaluation to the disposable investment and the long-term operating cost to be able to make the reasonable solution.In the frequency conversion velocity modulation for in the aqueous system design process, should choose the pump reasonably according to the service pipe net characteristic, achieved in satisfies the operation requirements under the premise, both saves the goal which the investment and conserves energy.MM420 变频器在给水系统的几点节能措施- 南京航大意航科技股份有限公司由于变频调速给水系统不需要建造传统给水系统的高位水箱、水塔，避免了二次污染并减少了土建投资，而且设计得合理能达到较好的节能效果。在给水系统中，定速泵只有在其高效段运行才能保证系统正常工作且没有能量浪费。在设计中，一般以管网的最不利情况 (此时流量最大，所需扬程也最大) 作为选择水泵机组的主要依据，但当管网流量减小时，能量的浪费不可避免，而且还可能造成低流量时管道内超压问题。水泵根据系统流量实时变化实现无级调速运行，是较好地解决以上问题，达到节能目的的途径之一。水泵调速可以通过很多途径实现，其中变频调速是目前较理想的一种。变频调速是通过给水系统管网上的压力传感器对管网的水压进行采样，将压力信号转换为电信号，并将其送至 PID 调节器与用户设置的压力值进行比较和运算，将结果转换为频率调节信号送至变频器。变频器根据传送过来的频率调节信号调整水泵电机的电源频率，从而实现调整水泵的转速。根据客户在实际使用中的要求变频调速给水系统可分为两种: 变压变量给水系统和恒压变量给水系统。变压变量给水系统的压力传感器设置在给水管网末端，PID 调节器设定值为管网末端用户所需的服务水头值。系统通过自动调节使管网末端水压保持恒定，使管路特性曲线和系统静扬程不变，而水泵出水口压力则随着供水量变化依管路特性曲线而改变，故理论上实现了“系统需要多少，机组提供多少” ，不会由于供水量的减小而产生多余的静扬程，节能效果满意。但这只是一种理想情况，且系统中仅有变频泵在单独工作。由于变频设备比较昂贵，大型给水系统往往采用变频泵与定速泵