中央空调变频改造技术

1、the partys fine style, carry forward the traditional Chinese virtues, practicing the Socialist core values, vigorously carry forward the spirit of Jiao Yulu, Hongqi Canal spirit and spirit of persistence, honesty in politics, strict statesman, stick to the spiritual heights of the Communists. Four t

2、o devotion, as, do play a role in qualifying. Official Communist duty. To fulfill the partys purpose, maintain for the people themselves, and dedication, devotion, maintain pioneer, pioneering and enterprising spirit, active at the well-off extra practice, make contributions. The incentive function

3、of party organizations at all levels should give full play to advanced models, establish a representative, advanced and typical of the times, and guide the broad masses of party members to emulate. In honor of the 95 anniversary of founding as an opportunity to award in recognition of a number of ou

4、tstanding party members advanced grass-roots party organizations, outstanding party workers, and put the pioneer trees. Third, the reform efforts for example, be sure to change into. Learning to teachEducation in order to solve the problem, if it does not solve the problem, it will form, goes throug

5、h the motions. To strengthen the consciousness of problems and insisted on problem-oriented, problem-solving learning education for traction, truly deep investigation into change, modification. A checked swing. Learning education programme for party-building in our city actually proposed to focus on

6、 solution of fuzzy ideals and beliefs waver, consciousness, purpose of the party weak sense, honesty and self-discipline awareness is not strong, depressed, six issues of ethical misconduct study contents specific programmes for all party members and leading cadres above the county level shall focus

7、 on further refinement to the problems. Specific to every party member and every cadre, also requires a combination of actual and controlled, focused and really put yourself in, people see things, see, with their own specific problems to learn Constitution Party rules, series, address, so precision

8、to find the problem, laying a solid foundation for further corrective action. B to make change. For check put of problem, through established rectification Taiwan account, and take special supervision, and on account PIN, approach, insisted do side learn side modified, and that know that modified, w

9、hile focused on put two learn a do learning education rectification with grasp party of mass line education practice activities and three strict three real topic education problem rectification combined up, consolidation expanded has made of rectification results, strongly corrected for officer not

10、for, and Chi and endless corrected four wind, and regulation masses side of abuses, ensure work advance more powerful, and problem solution more completely. Third, we must consolidate our achievements. For more public, some party members who focus on the outstanding issues, combining concentrated中央空

11、调系统PLC与变频器在中央空调节能改造技术中的综合应用 中央空调循环水系统的工作示意图中央空调水系统的节能分析1.变水量系统的基本原理变水量系统运行的基本原理可用热力学第一定律表述为：q=QCt 式中：q系统冷负荷；Q冷水流量 ；C水的比热；t冷水系统送回水温差热力学第一定律表明，在冷水系统中，可以根据实际冷负荷的大小调整冷水流量或冷水系统送回水温差。在冷水系统盘管或负荷末端，进行冷水系统设计时， q 、C、t 已经确定，q 为系统设计工况下的冷负荷，t 为按规范确定的温差，一般取 5 ，因此冷水量也被确定，系统按这些值设计选择设备。当系统设计完成并投入运行后， q 成了独立参数，它与室外的气

12、象条件和室内散热量等诸多因素相关。当系统冷负荷 q 变化时，由热力学第一定律，系统也必须相应改变冷水流量Q或温差t的大小。例如当冷负荷在某一时刻为设计值的 50 % ，并且冷水送水温度不变，如果改变送回水温差 t ，而保持流量Q不变，则形成定流量系统。如果保持冷水送回水温差t不变，改变冷水流量Q则形成变水量系统。理想的变水量系统，其送回水温差保持不变，而使冷水流量与负荷成线性关系2.水泵的基本原理离心水泵的相似定律又称为比例定律，表示如下：（1） （2） （3） 公式中Q水泵流量；H水泵扬程 ；P水泵功率；n水泵转速。3. 水泵变频调速节能原理中央空调系统中的冷冻水系统、冷却水系统是完成外部热

13、交换的两个循环水系统。以前，对水流量的控制是通过挡板和阀门来调节的，许多电能被白白浪费在挡板和阀门上；如果换成交流调速系统，把浪费在挡板和阀门上的能量节省下来，每台冷冻水泵、冷却水泵平均节能效果就很可观。故采用交流变频技术控制水泵的运行，是目前中央空调水系统节能改造的有效途经之一。 对于变频调速来说，转速基本上与电源频率f成正比，而对于水泵来说，根据相似定律，即公式可知：水泵流量与频率成正比，水泵扬程与频率的平方成正比，水泵消耗的功率与频率的三次方成正比。扬程 - 流量(HQ)关系曲线曲线为泵在转速n1下的扬程-流量特性，曲线为泵在转速n2下的扬程-流量特性，曲线为阀门关小时的管阻特性曲线，为

14、阀门正常时的管阻特性。三、中央空调节能改造实例1.兖州宾馆原中央空调系统的概况兖州宾馆中央空调为一次泵系统，冷冻水泵和冷却泵电机全年恒速运行，冷冻水和冷却水进出水温差都约为2 ，采用继电接触器控制。冷水机组：中央空调系统采用两台（一用一备）开利水冷冷水机组，单机制冷量为400USRT，电动机功率为300KW。冷冻水泵：冷冻水泵两台（一用一备），电动机功率为55KW，电机启动方式为自耦变压器启动。 冷却水泵：冷却水泵两台（一用一备），电动机功率为75KW，电机启动方式为自耦变压器启动。冷却塔风机：冷却塔三座，每座风机台数为一台，风机额定功率为5. 5KW，额定电流为13A，电机启动方式为直接启动

15、。该大厦中央空调系统的最大负载能力是按照天气最热，负荷最大的条件来设计的，存在着很大宽裕量，但实际上系统极少在这些极限条件下工作。一年中只有几十天时间中央空调处于最大负荷。大厦原中央空调水系统除了存在很大的能量损耗，同时还会带来以下一系列问题： (1)水流量过大使循环水系统的温差降低，恶化了主机的工作条件、引起主机热交换效率下降，造成额外的电能损失。 (2)水泵采用自耦变压器启动起动，电动机的起动电流较大，会对供电系统带来一定冲击。(3)传统的水泵起、停控制不能实现软起、软停，在水泵起动和停止时，会出现水锤现象，对管网造成较大冲击，容易对机械零件、轴承、阀门、管道等造成破坏，增加维修工作量和备

16、件费用。为使循环水量与负荷变化相适应，采用成熟的变频调速技术对循环系统进行改造，是降低水循环系统能耗的较好解决方案。一方面能够控制冷冻（却）泵的转速，即改变冷冻（却）水的流量，来跟踪冷冻（却）水的需求量，随着负载的变化调节水流量，从而节约能源；另一方面，因变频器是软启动方式，电机在启动时及运转过程中均无冲击电流，可有效延长电机、接触器及机械散件、轴承、阀门、管道的使用寿命。2. 节能改造措施 结合大厦原中央空调水系统的实际情况，确定大厦水系统节能改造措施如下：（1）由于系统中冷却水泵功率为75KW，相对主机功率接近30 较大，故对冷却水系统和冷冻水系统都进行变流量改造，在保证机组安全可靠运行的

17、基础上，取得最大化的节能效果。（2）冷冻水系统的控制方案采用定温差控制方法，因为冷冻水系统的温差控制适宜用于一次泵定流量系统的改造，施工较容易，将冷冻水的送回水温差控制在4.55。PLC通过温度传感器及温度模块将冷冻水的出水温度和回水温度读入内存，根据回水和出水的温差值来控制变频器的转速，从而调节冷冻水的流量，控制热交换的速度。温差大，说明室内温度高，应提高冷冻泵的转速，加快冷冻水的循环速度以增加流量，加快热交换的速度；反之温差小，则说明室内温度低，可降低冷冻泵的转速，减缓冷冻水的循环速度以降低流量，减缓热交换的速度，达到节能的目的。（3）冷却水系统的控制方案也采用定温差控制方法，因为冷却水系

18、统定温差控制的主机性能明显优于冷却水出水温度控制，将冷却水的进出水温差控制在4.55。PLC通过温度传感器及温度模块将冷却水的出水温度和进水温度读入内存，根据出水和进水的温差值来控制变频器的转速，调节冷却水的流量，控制热交换的速度。因此，对冷却水来说，以出水和进水的温差作为控制依据，实现出水和进水的恒温差控制是比较合理的。温差大，说明冷冻机组产生的热量大，应提高冷却泵的转速，加大冷却水的循环速度；温差小，说明冷冻机组产生的热量小，应降低冷却泵的转速，减缓冷却水的循环速度，达到节能的目的。（4）由于冷却塔风机的额定功率为5. 5KW，比较小，故不考虑对风机进行变频调速。（5）两台冷却水泵M1、M

19、2和两台冷冻水泵M3、M4的转速控制采用变频节能改造方案。正常情况下，系统运行在变频节能状态，其上限运行频率为50HZ，下限运行频率为30HZ；当节能系统出现故障时，可以启动原水泵的控制回路使电动机投入工频运行；在变频节能状态下可以自动调节频率，也可以手动调节频率，每次的调节量为0.5HZ。两台冷冻水泵（或冷却水泵）可以进行手动轮换。3.节能改造控制系统的功能结构图控制系统的功能结构图4. 节能改造控制系统的设计(以冷却水泵为例)（1）设计方案冷却水泵M1的主回路电气原理图（2）控制系统的IO分配及系统接线IO分配根据系统控制要求，选用F940GOT-SWD触摸屏，触摸屏和PLC输入、输出分配

20、如下：X0：变频器报警输出信号； M0：冷却泵起动按钮； M1：冷却泵停止按钮；M2：冷却泵手动加速； M3：冷却泵手动减速； M5：变频器报警复位；M6：冷却泵M1运行； M7：冷却泵M2运行； M10：冷却泵手自动调速切换；Y0：变频运行信号(STF)； Y1：变频器报警复位； Y4：变频器报警指示，Y6：冷却泵自动调速指示； Y10：冷却泵M1变频运行； Y11：冷却泵M2变频运行。数据寄存器D20为冷却水回水温度，D21为冷却水出水温度，D25为冷却水出回水温差，D1001为变频器运行频率显示，D1010为DA转换前的数字量。系统接线冷却泵的接线图（3）触摸屏画面制作触摸屏画面(a)

21、触摸屏首页画面 (b) 触摸屏操作画面 (c) 触摸屏监视画面（4）编制程序控制程序主要由以下几部分组成：冷却水出进水温度检测及温差计算程序CH l通道为冷却水进水温度（D20），CH2通道为冷却水出水温度（D21），D25为冷却水出进水温差。冷却水出进水温度检测及温差计算程序D / A转换程序进行D / A数模转换的数字量存放在数据寄存器D1010中，它通过FX2N-2DA模块将数字量变成模拟量，由CH l通道输出给变频器，从而控制变频器的转速以达到调节水泵转速的目的。D / A转换程序手动调速程序 手动调速程序自动调速程序自动调速程序变频器、水泵启停报警的控制程序变频器的启、停、报警、复位

22、，冷却泵的轮换及变频器频率的设定、频率和时间的显示等均采用基本逻辑指令来控制。变频器、水泵启停报警的控制程序reinforcing declare hidden wall reinforcing test next step. Base plate Joint: reinforced joints staggered,aasxq Taiwan. C. According to the design prepared templates, connectors, and support, release agents, cleaning preparations for material pre

23、paration and manipulation tools. D. numbers after assembling, and paint release agents, specification pile up. E. place axis, template line level elevation, template, locate the line of control and the line of control, templates should do the leveling layer at the bottom. F. installation sequence: a

24、. before installation check: must be carefully inspected before installation template edge level elevation, template, the line of control and the correctness of the line of control, check the smoothness of leveling layer at the bottom of the template, sponge form is correct, Complete. B. welding wal

25、l spacer bars: from the roof at 50mm, according to the axis of the wall wall positioning of welding steel, using steel 600 12, welding. Basements outer defence walls and air walls are made of steel 900 12, plum blossom features as wall thickness control based on, and positive and negative zero wall

26、above the middle of the basement wall with grade concrete with wall support 600 plum blossom arrangement to ensure the wall thickness. C. template installation: template installation should be in place, calibration, and installation ofrectification and strengthening the management of daily education

27、, the spirit of reform short of the complete system, pay close attention to system implementation, really make the party organization and party member education and strict management, solid. Finally, the urge work on the lead, be sure to promote efficiency. Two education, not on education educationa

28、l, not working with the Centre two, must stick around the Center, serving the overall situation, coordinate, truly result-oriented and promote efficiency. Current and future a period, to tightly around coordination advance four a full strategy layout, winning full built society this a central and wo

29、rk overall, put carried out learning education as promoted work of important opportunities and powerful power, guide General members cadres insisted development first priority, active adapted economic development new normal, consciously practice line five big development concept, effective grasp sup

30、ply side structural reform, to guarantees and improved livelihood, construction more high ecological vitality happiness of city. Last year, we carry out three-three activities as a three-three special education important, find education and effective platform to facilitate the combination of work. R

31、eference this a good practices, provincial, and municipal decided in two learn a do learning education in the carried out five check five promoting, the County District units to insisted put two learn a do learning education and five check five promoting organic fusion, and common advance, do one pl

32、an layout, and one organization implementation, put carried out two learn a do situation, and five check five promoting situation as party work evaluation of importantContent, as an important aspect of mutual evaluation on party members, testing as an important basis for leading bodies and leading cadres performance and guide the broad masses of party members and cadres to study education opens up to