空中有东西

2021年2月19日

随着汽车行业的电气化，野心迅速将其转移到航空时期。液压系统让位于电动系统。由于质量减少，该系统的供应电压增加以允许更大的范围。在商业航空的早期，所有人都控制着…Read More

随着汽车行业的电气化，野心迅速将其转移到航空时期。液压系统让位于电动系统。由于质量减少，该系统的供应电压增加以允许更大的范围。

在商业航空的早期，所有控制命令均在电线绳索或推杆的帮助下进行。这具有优势：力量可以毫不拖延，不会损失。由于当时的飞机很小，飞行员可以用肌肉力量操作一切。但是，仅驾驶具有肌肉力量的现代宽阔飞机是完全不可能的。

液压
为了应用这种力，使用了液压技术。早在1795年，一位名叫约瑟夫·布拉马（Joseph Bramah）的英国人开发了一台由加压水提供动力的水力力学机器。该机器利用水的力量将现有的肌肉功率提高了2000倍。原则上，任何液体都适合此目的。液压油由于其化学和热性能而占了上风。

This is how it works
液压enable forces to be transmitted over almost any distance. With a purely mechanical power transmission, you always need a drive shaft or push rods and cables to provide propulsion. In an aircraft, however, space is at a premium. That’s why the use of hydraulics quickly gained acceptance. Since the entire system must be under pressure, pumps are needed on board to provide it permanently or for a specific purpose (e.g. landing gear). For the sake of safety, hydraulic systems in such applications are always designed redundantly.

液压驱动器的优缺点
Hydraulic systems generate very high pressures and thus large forces in a small space. Once the pressure has been built up, a hydraulic drive can hold the desired position for any length of time without requiring additional energy.

However, this is also a weak point of hydraulic systems: Where high pressures are generated, the loss of energy in the event of leakage is high. In addition to leaks, contamination can also occur in the used pipes. The viscosity of the hydraulic oil is also dependent on the outside temperature, and further pressure losses occur due to the compressibility of the oil. The main argument against hydraulics in future aircraft, however, is their high mass. For safety reasons, they must be equipped with a lot of margin and have a redundant design. This makes them very heavy. In short: hydraulic drives are more vulnerable and require more maintenance than their electric counterparts.

Pros and cons of electric drives
Electric drives are considered easy to control. During movement, they consume less energy than hydraulic drives. They operate largely without jerks. New possibilities for integration into the aircraft structure and into the control system significantly expand the range of applications. Compared to hydraulic systems, an electric drive system is easier to install. It requires less space in the vast majority of applications, as there are no hoses and pumps that need regular maintenance. An electric drive has a long service life and requires little or no maintenance. Although the initial investment costs are higher, they are quickly amortised by the more favourable operation.

Disadvantages of electric drives are said to be the linear movement in connection with a high expenditure of force. And as already mentioned: A hydraulic drive can remain in a loaded position without any further energy supply, whereas an electric motor must maintain this position throughout the entire process in order to the necessary force.

下一个：电压向上 - 电流下降

电压向上 - 电流下降
Analogue to automotive technology, the developers of electric aircraft are taking the path of high system voltage. Power is the product of voltage times current. If the system voltage for actuators and control units as well as drive systems such as propellers is increased, only low currents flow. This allows the use of thinner and thus lighter cables. In this way, mass can be saved. With the vast amount of cables that are installed in an aircraft, this adds up to a lot. Less mass leads to lower energy consumption, the aircraft allows greater ranges.

可靠性和安全性
毋庸置疑，未来的电动飞机将必须与以前相同的安全要求。但这并不是那么容易：您必须为飞机提供很多动力。这里需要大约1000 V的系统电压和几百千瓦的输出。冗余系统的使用是给定的。这里正在追求各种各样的概念。例如，配备四个螺旋桨的无人机（四轮驱动器）也必须能够安全地降落，如果一个系统失败。

要求

这些数字意味着极端的要求放置on the electrical fuse protection, on a fail-safe concept. Such fuses are designed for continuous currents of several hundred amperes, must be able to interrupt very reliably, precisely and quickly in the event of a malfunction and have a breaking capacity of several kA at 1 kV. In addition, they must be small, light and absolutely reliable.

Experience from space technology

SCHURTER, the仅欧洲航天局的合格保险丝供应商（MGA-S和HCSF）自2008年以来，人们意识到此类需求在开发和过程质量方面对保险丝提出了问题。基于已经可用的UMT-W，超紧密的，防脉冲的SMD保险丝1000的分断能力,研究is being conducted into even more powerful versions.

TheSCHURTER UMT-W非常适合具有特别长电缆的应用，例如在航空中常见的应用，这些应用在主要侧通过电子保险丝保护。如果此监视失败或不正确执行其任务，则UMT-W接管了故障安全设备，并将系统传输到安全的降低状态。

公司

The SCHURTER Group is a globally successful Swiss family business. With our components ensuring the clean and safe supply of power, input systems for ease of use and sophisticated overall solutions, we impress our customers with agility and excellent product and service quality. We focus on industrial equipment, medical equipment, automotive, avionics and space, data and communication and energy.