風(fēng)閥執(zhí)行器——電動 VS 氣動（中英文）
電動和氣動執(zhí)行器通過控制風(fēng)門和閥門在 HVAC 系統(tǒng)中發(fā)揮著核心作用，但它們的工作方式有著根本的不同。電動執(zhí)行器響應(yīng)控制信號（通常為2至10伏直流電或4至20毫安）來精確調(diào)整其位置。相反，氣動執(zhí)行器依靠壓縮空氣壓力（也稱為空氣信號）來工作。這需要專用的供氣管線和配套設(shè)備。雖然氣動系統(tǒng)曾經(jīng)被廣泛使用，但由于電動執(zhí)行器具有更高的精度、更容易的安裝和流線型設(shè)計，它已經(jīng)成為標(biāo)準(zhǔn)。例如，Belimo 的直接耦合電動執(zhí)行器無需氣管、壓縮機(jī)、傳感器或定位器，而這些是氣動裝置中必不可少的組件。
Electric and pneumatic actuators play central roles in HVAC systems by controlling dampers and valves, yet they differ fundamentally in how they operate. Electric actuators respond to a control signal, typically between 2 and 10 volts DC or 4 to 20 milliamps, to adjust their position precisely. In contrast, pneumatic actuators rely on compressed air pressure to function, also known as an air signal. This requires dedicated air supply lines and supporting equipment. Although pneumatic systems were once widely used, electric actuation has become the standard thanks to its enhanced precision, easier installation, and streamlined design. Belimo’s direct-coupled electric actuators, for example, eliminate the need for air lines, compressors, transducers, or positioners, components that are mandatory in pneumatic setups.
什么是滯后？
What is hysteresis?
滯后是指控制信號與執(zhí)行器實際位置之間的差異，具體取決于運動方向。在氣動系統(tǒng)中，連桿、閥桿卡緊、密封件和其他機(jī)械阻力產(chǎn)生的內(nèi)部摩擦力都會造成這種影響。由于氣動控制信號也充當(dāng)動力源，它必須超過目標(biāo)值才能克服阻力，這通常會導(dǎo)致過沖。當(dāng)信號反向時，它必須低于彈簧力才能啟動運動，這也會導(dǎo)致位置誤差。
Hysteresis refers to the difference between the control signal and the actual position of the actuator depending on the direction of movement. In pneumatic systems, internal friction from linkages, stem binding, seals, and other mechanical resistance contributes to this effect. Because the air control signal also acts as the power source, it must exceed the target to overcome resistance, often leading to overshoot. When the signal reverses direction, it must drop below the spring force to initiate movement, also contributing to positional error.
為什么電動執(zhí)行器比氣動執(zhí)行器更精確？
Why is electric actuation more accurate than pneumatic actuation?
像Belimo這樣的電動執(zhí)行器專為精確定位而設(shè)計，其正常滯后僅為1%。Belimo通過內(nèi)部反饋電路持續(xù)比較輸入信號與實際軸位置，將滯后降至最低。相比之下，氣動執(zhí)行器在 5 PSI 的彈簧范圍內(nèi)通常表現(xiàn)出約 1.5 PSI 的滯后。額外的機(jī)械負(fù)載會加劇這種影響，進(jìn)一步降低精度。
Electric actuators like Belimo’s are designed for precision positioning, with a normal hysteresis of just 1%. Belimo minimizes this through internal feedback circuits that continuously compare the input signal to the actual shaft position. Pneumatic actuators, by contrast, typically exhibit around 1.5 PSI of hysteresis over a 5 PSI spring range. Additional mechanical loading increases this effect, further reducing accuracy.
與氣動混合執(zhí)行器相比，Belimo電動執(zhí)行器的分辨率是多少？
What is the resolution of Belimo electric actuators compared to pneumatic hybrids?
Belimo執(zhí)行器的最小分辨率為 160:1，這使得它們能夠響應(yīng)控制信號的微小變化。典型的 DDC 控制器可以輸出 0.1 VDC 的分辨率，而 Belimo 的內(nèi)部電路可以達(dá)到這一水平。氣動混合系統(tǒng)（包括 DDC 控制器、傳感器、定位器和執(zhí)行器）在實際應(yīng)用中只能達(dá)到約 20:1 的分辨率。
Belimo actuators have a minimum resolution of 160:1, allowing them to respond to very small changes in the control signal. A typical DDC controller can output with 0.1 VDC resolution, and Belimo’s internal circuitry can match that. Pneumatic hybrid systems, which include a DDC controller, transducer, positioner, and actuator, can only achieve about 20:1 resolution in practice.
為什么氣動執(zhí)行器無法始終準(zhǔn)確響應(yīng)控制信號？
Why don’t pneumatic actuators always respond predictably to the control signal?
氣動執(zhí)行器通常并非僅根據(jù)控制信號進(jìn)行定位。最終位置取決于空氣信號力、彈簧力、阻尼器負(fù)載和阻力的凈效應(yīng)。這些相互作用力可能會導(dǎo)致有效彈簧行程發(fā)生顯著變化。例如，如果阻尼器負(fù)載作用方向與空氣信號方向相同，那么彈簧行程范圍為 8 至 13 PSI 的執(zhí)行器實際上可能在 4 PSI 時就開始移動。這會導(dǎo)致定位不一致，控制分辨率降低。
Pneumatic actuators often do not position based solely on the control signal. The final position depends on the net effect of air signal force, spring force, damper load, and resistance. These interacting forces can cause significant shifts in the effective spring range. For example, an actuator with an 8 to 13 PSI spring range could actually begin to move at 4 PSI if the damper load acts in the same direction as the air signal. The result is inconsistent positioning and reduced control resolution.
定位器能提高氣動執(zhí)行器的精度嗎？
Can positioners improve the accuracy of pneumatic actuators?
可以，但作用有限。單臺氣動執(zhí)行器的精度可能在+/-15%。使用定位器后，精度可以提高到5%左右，但這會增加復(fù)雜性和維護(hù)成本。機(jī)械定位器會隨著時間的推移，由于磨損、彈簧疲勞和校準(zhǔn)漂移而性能下降。信號鏈中的每個組件，包括傳感器、定位器和執(zhí)行器，都會引入誤差。隨著時間的推移，即使經(jīng)過精心設(shè)置，精度也會持續(xù)下降。
Yes, but only to a limited extent. A pneumatic actuator alone may have accuracy of +/-15%. With a positioner, this can improve to about five percent, but this comes with added complexity and maintenance. Mechanical positioners degrade over time due to wear, spring fatigue, and calibration drift. Each component in the signal chain, including the transducer, positioner and actuator, introduces error. Over time, even with careful setup, accuracy continues to decline.
執(zhí)行器性能如何影響溫度控制和能源效率？
How does actuator performance affect temperature control and energy efficiency?
精確的執(zhí)行器直接影響熱舒適度和能源效率。具有緊密滯后和高分辨率的電動執(zhí)行器能夠緊密跟蹤控制信號，將溫度保持在允許范圍內(nèi)，并最大限度地減少能源浪費。氣動執(zhí)行器本身存在精度問題，容易出現(xiàn)位置漂移，尤其是在扭矩負(fù)載變化或風(fēng)速較高的情況下。這會導(dǎo)致溫度和氣流控制出現(xiàn)過沖、欠沖和不穩(wěn)定的情況。
Precision actuation directly impacts thermal comfort and energy efficiency. Electric actuators with tight hysteresis and high-resolution track the control signal closely, keeping temperatures within range and minimizing energy waste. Pneumatic actuators, with their inherent inaccuracy, tend to hunt for position, especially under varying torque loads or high air velocities. This results in overshoot, undershoot, and instability in temperature and airflow control.
電動執(zhí)行器是否比氣動系統(tǒng)更可靠？
Are electric actuators more reliable than pneumatic systems over time?
是的。雖然氣動執(zhí)行器本身機(jī)械性能可能非常耐用，但其周圍的組件（例如傳感器、壓縮機(jī)、干燥器、過濾器和配件）可能會引發(fā)多個故障點。氣動系統(tǒng)的維護(hù)可能涉及多達(dá) 23 個組件。Belimo的電動系統(tǒng)僅需三個組件：線路、DDC 面板和變壓器。Belimo電子執(zhí)行器預(yù)計至少可完成 60,000 個全行程循環(huán)，并且?guī)缀鯚o需維護(hù)，使用壽命可達(dá) 15 至 20 年。在兩年的保修期內(nèi)，Belimo執(zhí)行器的故障率僅為 0.3%。
Yes. While pneumatic actuators themselves may be mechanically durable, the surrounding components, such as transducers, compressors, driers, filters, and fittings, can introduce multiple points of failure. Maintenance for a pneumatic system can involve up to 23 components. Belimo’s electric systems require just three: wiring, the DDC panel, and a transformer. Belimo electronic actuators are expected to last a minimum of 60,000 full stroke cycles, and 15 to 20 years with minimal maintenance. Belimo actuators have a failure rate of just 0.3 percent over a 2-year warranty period.
氣動執(zhí)行器有哪些缺點？
What are the disadvantages of pneumatic actuators?
氣動執(zhí)行器通常在需要精確中間定位的調(diào)節(jié)控制應(yīng)用中表現(xiàn)不佳。由于磁滯和內(nèi)部摩擦，氣動執(zhí)行器只有其全行程的 20% 到 50% 可用于可靠控制。此外，它們還依賴于壓縮機(jī)、傳感器和氣站等外部組件，這會帶來額外的維護(hù)需求和潛在的故障點。
Pneumatic actuators typically perform poorly in modulating control applications that demand accurate intermediate positioning. Due to hysteresis and internal friction, only 20 to 50 percent of a pneumatic actuator’s full stroke may be usable for reliable control. They also rely on external components like compressors, transducers, and air stations, which introduce additional maintenance requirements and potential points of failure.
電動執(zhí)行器有哪些缺點？
What are the disadvantages of electric actuators?
在極端高負(fù)載或特定工藝應(yīng)用中，電動執(zhí)行器可能需要額外的保護(hù)或設(shè)計考慮，而這些應(yīng)用傳統(tǒng)上通常使用快速動作的氣動裝置。但對于絕大多數(shù)暖通空調(diào) (HVAC) 應(yīng)用而言，電動執(zhí)行器不僅能滿足性能要求，還能提供卓越的控制靈活性和一致性。
Electric actuators may require additional protection or design considerations in extreme high-load or process-specific applications where fast-acting pneumatic devices have traditionally been used. But for the vast majority of HVAC applications, electric actuation not only meets performance requirements but also delivers superior control flexibility and consistency.
電動執(zhí)行器和氣動執(zhí)行器的成本差異是什么？
What are the cost differences between electric and pneumatic actuation?
Belimo電動執(zhí)行器的初始安裝成本通常較低。相比彈簧復(fù)位阻尼器的完整配置，如果將傳感器、定位器、人工和共用氣站基礎(chǔ)設(shè)施的成本計算在內(nèi)，電動系統(tǒng)的成本低于氣動系統(tǒng)。隨著時間的推移，這種差異會越來越大。氣動系統(tǒng)需要持續(xù)維護(hù)更多組件，而Belimo的電動解決方案僅涉及接線、DDC面板和變壓器。由于無需定期維護(hù)，并且通過更佳的控制實現(xiàn)更高的效率，電動執(zhí)行器的生命周期成本顯著降低。
Initial installation costs are typically lower for Belimo electric actuators. When comparing a complete setup for a spring return damper, electric systems are less expensive than pneumatic systems once the costs of transducers, positioners, labor, and shared air station infrastructure are included. The difference becomes even greater over time. Pneumatic systems require ongoing maintenance across many more components, while Belimo’s electric solution involves only wiring, a DDC panel, and a transformer. With no recurring service needs and higher efficiency through better control, the life cycle cost of electric actuation is significantly lower.
氣動和電動哪個更好？
Which is better, pneumatic or electric?
在大多數(shù)暖通空調(diào) (HVAC) 應(yīng)用中，電動執(zhí)行器可提供更高的精度、可靠性、分辨率和能效。雖然氣動系統(tǒng)可以在精度要求較低的簡單雙位控制場景中提供更高的扭矩，但電動執(zhí)行器通常能夠滿足這些扭矩需求，同時提供卓越的一致性和長期成本節(jié)約。對于需要精確定位和重復(fù)性的調(diào)節(jié)控制，電動執(zhí)行器明顯更適合，并且避免了氣動系統(tǒng)常見的漂移、滯后和振蕩現(xiàn)象。在寒冷的環(huán)境中，由于氣管和氣動元件容易凍結(jié)，電動執(zhí)行器更適合，尤其是在需要位置反饋的情況下。Belimo提供故障安全和非故障安全型號來滿足這些需求。
Electric actuation offers better accuracy, reliability, resolution, and energy efficiency in most HVAC applications. While pneumatic systems can deliver higher torque in simple two-position control scenarios where precision is less critical, electric actuators often meet those torque demands while providing superior consistency and long-term cost savings. For modulating control, where accurate positioning and repeatability are required, electric actuation is a significantly better fit and avoids the drift, hysteresis, and hunting associated with pneumatic systems. In cold ambient environments, where air lines and pneumatic components are prone to freezing, electric actuation is the better fit, especially when position feedback is required. Belimo offers both fail-safe and non fail-safe models to meet these needs.
聲明：
-文章轉(zhuǎn)載自BELIMO，如有侵權(quán)，請聯(lián)系刪除！
-如有偏頗，歡迎指正！
滬公網(wǎng)安備31011002006738號
