日光采集设计与应用

以下初稿来自照明122-02王琴瑶

COURSE DESCRIPTION
课程描述

Welcome to Part 2 of the EE201: Daylight harvesting course, covering design and application of a daylight harvesting control system. Daylight Harvesting, Part 2: Design and Application (1) and Part 3: Design and Application (2) describe a simple process for design and application of lighting controls used to enact energy-saving daylight harvesting control strategies. Part 2 educates participants about two critical initial decisions—whether the lighting should be switched or dimmed in response to daylight, and whether the system should be open or closed loop.
欢迎来到EE201：日光采集课程的第二部分，课程涵盖了日光采集控制系统的设计与应用。日光采集，第二部分：设计与应用（1）和第三部分：设计与应用（2）描述了一个简单的设计与应用的过程，是用于制定节能日光采集控制策略的照明控制的设计与应用过程。第二部分教给学员两种临界情况的初步选定—灯具是否应该对日光做出响应从而开关或调节明暗，以及系统是否应该开环或者闭环。

Daylighting, the use of daylight as a primary source of general illumination in a space, has become a more important feature of mainstream construction due to the sustainable design movement.
天然采光，将日光作为主要来源应用于空间一般照明，由于其可持续的设计方案，已成为主流建设中的一个更为重要的特征。

Numerous studies over the last 50 years attest to the importance of daylight in design. Research indicates that daylight can improve user satisfaction/performance and retail sales. These characteristics can make daylighted buildings more valuable and marketable.
过去50年中大量的研究证明了日光的设计的重要性。研究表明，采用日光可以提升用户的满意度或表现以及零售销售额。这些特性可使采用日光照明的建筑更有价值及市场销路。

Daylighting also enables daylight harvesting, a control strategy that has been demonstrated to generate up to 70 percent lighting energy savings. A daylight harvesting system decreases electric light contribution as daylight contribution increases.
天然采光同时也实现日光的采集，该控制策略已被证明能够节约高达30%的能量。日光采集系统通过增加日光来供应照明以减少使用电力供应照明。

LEARNING OBJECTIVES
学习目标

At the end of the course, participants will be able to:
在课程结束后，学员将能够掌握：
select dimming or switching as the output of the daylight harvesting control system, based on how the space is used.
在空间中如何使用和选择调暗或者开关来控制日光采集控制系统的输出。
distinguish between open- and closed-loop daylight harvesting control systems, and select an appropriate solution based on the application.
辨别开环和闭环日光采集控制系统之间的区别，并基于实际应用选择合适的解决方案。
place photosensors in the space appropriately based on whether the control system is open or closed loop.
根据控制系统处于开环或者闭环模式，把光电传感器放置在合适的空间位置上。
have general knowledge needed to begin designing a daylight harvesting control system.
掌握设计一个日光采集控制系统所需的基本知识。

DIMMING VERSUS SWITCHING
调光与开关

A key design decision will be how to control the lights. The two choices are switching or dimming:
这是一个关键的设计决策，它将决定如何控制灯光。这里有两个选择，分别是开关切换和调光：

Switching entails separate circuiting and control of alternate lamps/ballasts, fixtures or fixture rows, enabling one or more steps between OFF and full output.
开关意味着断开回路和灯具、镇流器的控制、装置以及装置电路，能够实现在关闭和全开状态之间进行一阶或多阶段调节。

Step dimming is similar to switching but the change in lighting state occurs across all lamps, providing a uniform visual appearance.
分步调光与开关切换类似，但是在照明设备状态上的变化是发生在所有灯具部件上的，它提供一个统一的视觉外观。

Continuous dimming enables a smooth, continuous change in light level across the given dimming range.
连续调光能够在给定调光范围内的灯光级别上实现平滑、连续的变化。

CONTINUOUS DIMMING
连续调光

Continuous dimming offers much broader flexibility, resulting in greater control accuracy. This, coupled with smooth transitions between light levels, increases the likelihood of occupant acceptance.
连续调光具有更宽泛的灵活性，从而能更好地控制精度。这点外加上灯光级别上的平滑过渡，提高了使用者接受该方式的可能性。

Due to its relatively high degree of control accuracy, dimming can produce higher energy savings in spaces where daylight levels are highly variable and/or close to electric light levels. These systems typically present a higher initial cost and more sophisticated commissioning. Some manufacturers have introduced auto-commissioning capabilities for their products, which can reduce the complexity previously associated with calibration and testing.
由于其有相对较高的控制精度等级，调光可以在日光水平变化大和/或接近电力灯光照明水平的空间中产生更好的节能效果。这些系统明显地呈现出较高的初始投资成本以及更加复杂的调试过程。一些厂商纷纷在他们的产品中加入自动调试的功能，这可以有效降低之前校准和调试的复杂程度。

Due to its relative transparency, dimming is ideally suited to applications where:

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由于其相对明了，因此该调光非常适合应用于：

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1) occupants perform stationary or critical tasks;
2) daylight provides a smaller portion of the required light level or is highly variable; and/or
3) where light fixtures must be mounted in the normal field of view.
1）用户进行固定的或者重要的工作时；
2）日光提供所需的光照水平的一小部分，或者是高度变化的；以及/或者
3）灯具装置必须安装在正常视野范围内的地方。

SWITCHING
开关调控

Switching and step dimming traditionally presented a lower initial cost and are easier to commission (although the falling cost of dimming ballasts are bring costs into par, and automatic commissioning controls can simplify commissioning for dimming systems), but offer less control accuracy and potentially lower energy savings. For automatic control systems, there is also a risk of occupants not accepting it.
开关调控和分步调光在传统上呈现较低的投入成本而且更易调试(尽管调光镇流器成本花费的下降使整体成本趋于平价，并且自动调试控制能为调光系统简化调试的过程)，但是它的控制精度较低，而且可能出现较差的节能效果。对于自动的控制系统，也有一定的用户不接受该系统的风险性。

Due to the control system having less flexibility and accuracy, switching and step dimming daylight harvesting control systems typically generate high energy savings in applications with very high, consistent amounts of daylight.
由于具有较低的灵活度和准确度，开关调控和分步调光日光采集控制系统通常在要求日光照明水平高且需求量一致的这类应用中产生高效节能的效果。

Because the control effect is more intrusive than continuous dimming, switching and most step dimming daylight harvesting controls are ideally suited to applications where:
由于其控制效果比连续调光更加深入，开关调控和大多数分步调光日光采集控制非常适合应用于：

1) occupants perform non-stationary, non-critical tasks (e.g., hallways, atria);
2) daylight level is high and consistent (2-3 times greater than minimum electric light levels); and
3) light fixtures/lamps are mounted high and not in the normal field of view.
1）用户进行非固定、非重要工作的地方（例如：走廊，楼梯间）；
2）日光照明水平要求高且一致性高的地方（比最低的电光源照明水平高2-3倍）；以及
3）灯具装置/灯具安装得高且不在正常视野范围内的地方。

CLOSED VERSUS OPEN LOOP
闭环与开环

Another key decision point will be whether the daylight harvesting control system should be closed versus open loop.
另一个关键的决定点则是日光采集控制系统是否应该是闭环或者开环。

Closed loop systems measure the combined electric light and daylight level reflected from the task surface (see top image). This allows the designer to set a target light level that the controller maintains by adjusting electric light output through switching and/or dimming. The sensor "sees" the results of its adjustment and may make further adjustments based on this feedback, creating a CLOSED loop.
闭环系统测量的是混合型电力灯光和从工作面上的反射的日光的照明水平（见上方图）。这允许设计师通过开关和/或调光来调整电力的光输出，从而设定控制器可保持的目标照明水平。传感器“看到”（实为测量到）这个的调整结果，并可以基于该反馈结果进一步调整，形成闭环。

Placed at the daylight aperture or outside the building, open loop systems "see" only incoming daylight and adjust electric light output based on estimated task light levels (see bottom image). Because they "see" only daylight, they are OPEN loop.
开环系统放置在日光光孔或者建筑物外，“看到”的仅仅是传入的日光，并且基于估算的工作光照水平进行电力的光输出调整（见下方图片）。因为系统“看到”的仅仅是日光，所以称作开环。

以下初稿来自照明121-25 陈婷瑶

CLOSED LOOP
闭环
Closed loop systems are considered more precise than open loop. Sensor placement is more critical, however, particularly in spaces where indirect general lighting is installed. (This image shows typical locations for closed loop sensors.)
闭环系统被认作是比开环更精确的系统。传感器的位置更是关键，特别是安装间接照明的空间里。（这个图片展示闭环传感器安装的典型位置）

Commissioning is also typically more complex than with open loop systems, although some manufacturers have introduced closed loop sensors with auto-commissioning capabilities, making them simple to set up and calibrate.
Commissioning is also typically more complex than with open loop systems, although some manufacturers have introduced closed loop sensors with auto-commissioning capabilities, making them simple to set up and calibrate.
虽然一些厂家推出了拥有自动调试能力的闭环传感器，能使其更简单地进行设置和校准，但调试过程通常也比开环系统更复杂。

Ideal applications for closed loop systems include windows with blinds or shades, and spaces with frequently changing lighting conditions.
闭环系统的理想应用包括百叶窗或有窗帘的窗户，和能频繁改变照明条件的空间。
With closed loop systems, photosensor placement is critical. In windowed spaces, a rule of thumb is to place the sensor 2 window heights deep into the space. Sensor placement should take into account the possibility of changing reflectivity of tasks; for example, if the sensor is oriented towards a desk, the sensor will detect different light levels depending on what is placed on the desktop, such as white paper. In open interior spaces, consider allocating one sensor at least every 30 linear feet of window wall; for each partitioned space such as a private office, allocate one sensor per space. Consider operable shades and, if needed, consider additional sensors to account for differences in illumination caused by different shade positions.(Note that window height is commonly defined as distance from floor to top of glazing.)

闭环系统中光电传感器的位置是极重要的。在窗口的空间中，一条经验法则是将传感器安装在深入空间内两个窗户的高度。传感器的放置应考虑到目标会改变反射率的可能性；例如，如果传感器是面向书桌的，传感器将根据书桌上放置的物品检测到的不同的光照水平，如白色的纸。在宽敞的室内空间，应在直线长度至少为每30英尺的玻璃墙上配置一个传感器；每个分区的空间，如私人办公室，应分配一个传感器。考虑到可操作性的色调和，如果需要，可以考虑使用额外的传感器，因为不同的阴影位置会引起照明上的不同。（注意窗口的高度通常被定义为从地面到玻璃顶部的距离。）
When using closed loop systems, it is important to ensure that the photosensor not be placed with a direct view of substantial light emission from nearby indirect light fixtures. In some spaces, it may be advantageous to specify the photosensor as an integral component on the bottom face of the fixture, avoiding this issue. Similarly, avoid placing closed loop sensors where they receive exposure to direct sunlight, or are exposed to hard shadows caused by interior objects.

当采用闭环系统时，保证传感器不被放置在有大量从周围装置上反射出来的光线的地方时十分重要的。在一些地方，明确指出把传感器作为安装在固定装置底面的不可分割的部分会很有利，这样可以避免这一问题。同样，避免将闭环传感器安装在能接受到阳光直射的地方，或暴露于由于室内物体造成的阴影下。

OPEN LOOP
开环
Open loop systems enable multiple control zones to be controlled by a single photosensor. More forgiving of "errors" in placement of the sensor or its field of view, open loop systems offer greater calibration flexibility. Note that manual or automatic shading may block daylight, but the sensor may signal the controller to change the lights anyway; for this reason, local overrides are useful.
开环系统使多个控制区被一个光电传感器控制。更情有可原的“错误”是传感器的安装位置或者是它的感应范围，开环系统能提供校准的灵活性。注意，手动或自动遮阳可以阻挡阳光，但传感器在任何情况下都会警告控制者去改变光线；出于这个原因，局部覆盖是很有用的。
Ideal applications for open loop systems include skylights or clerestories (rows of windows set into upper walls) without shades as well as spaces with relatively constant daylighting conditions.
开环系统的理想应用包括没有阴影的天窗或通风窗（成排的窗户被置于顶墙上），和相对持续不变的日照空间条件。

With open loop systems, photosensors are typically placed at or near daylight apertures, oriented either towards incoming daylight or the closest reflected surface (as long as the reflected component does not include any electric light contribution). (Note that window height is commonly defined as distance from floor to top of glazing.)

开环系统中，光电传感器通常被放置于接近日光的缝隙附近，或者是朝向射进的日光，或者是最靠近反射面的地方（只要反射分量不包括任何电灯发出的光）。（注意窗口的高度通常被定义为从地面到玻璃顶部的距离。）

CLOSED VERSUS OPEN LOOP
闭环与开环

Often, there is no single ideal choice, with either closed or open loop systems being effective in the space, as long as the sensor is placed in a suitable location.
通常，没有单独的理想的选择，在空间中要么是关闭系统有效要么就是开环系统，只要传感器被置于在合适的位置上。

DUAL LOOP
双回路

A new alternative to closed and open loop systems combines these approaches in a system called dual loop. Developed at the California Lighting Technology Center in partnership with companies including WattStopper, dual loop systems utilize open and closed loop photodiodes looking in different directions.
一个新的可代替开环和闭环系统的事物在一个系统内结合了这些方法，被称之为双回路。在加利福尼亚照明技术中心和WattStopper公司，被合作开发出来，双回路系统采用开环和闭环光电二极管面向不同的方向。

Dual loop systems provide greater accuracy than using open loop alone, while providing greater resistance to transient light level changes than using closed loop alone.
双回路系统的精度比仅使用开环回路更高， 同时其抗瞬时照明等级变化的能力比仅使用闭环系统更强。