Design and Development of Multi-Lane Smart Electromechanical Actuators
Buy e-book PDF
The unavoidable element in the development of flight control systems (to date) has been in hydraulic actuators. This has been the case primarily because of their proven reliability and the lack of alternative technologies. However, the technology to build electromechanically actuated primary flight control systems is now available, which may mark the end of the hydraulic actuation systems - an important step for the development of the future 'all-electric' aircraft. Design and Development of Multi-Lane Smart Electromechanical Actuators describes design concepts in electromechanical actuators by considering an actuator that has the capability to drive the aerodynamic and inertial loads of an aileron control surface similar to that of the Sea Harrier. It provides the necessary theoretical background to design smart multi-lane electromechanical actuation systems, and provides a general methodology that engineers (electrical, mechanical, mechatronic, aerospace or chemical) will find useful.
Inspec keywords: intelligent actuators; electromechanical actuators
Other keywords: brushless dc motor; hardware cross monitoring; digital cross monitoring; architecture consolidation; control design; multi-lane smart electromechanical actuators
Subjects: General electrical engineering topics; Intelligent actuators; General control topics; Control gear and apparatus; Electromechanical actuators
- Book DOI: 10.1049/PBCE093E
- Chapter DOI: 10.1049/PBCE093E
- ISBN: 9781849196550
- e-ISBN: 9781849196567
- Page count: 128
- Format: PDF
-
Front Matter
- + Show details - Hide details
-
p.
(1)
-
1 Introduction
- + Show details - Hide details
-
p.
1
–3
(3)
This chapter gives a brief review of electromechanical actuators and an introduction to the topics covered in the other chapters.
-
2 Relevant developments
- + Show details - Hide details
-
p.
5
–13
(9)
It is the aim of this chapter to present state of the art developments in electrohydraulic, electromagnetic and electromechanical actuators that led the way and influenced actuation designs for the future all-electric aircraft development.
-
3 Modelling the brushless dc motor
- + Show details - Hide details
-
p.
15
–34
(20)
This chapters covers the lumped mathematical model and the three-phase mathematical model.
-
4 Control design
- + Show details - Hide details
-
p.
35
–54
(20)
This chapter is dedicated to outline the control system design of the multi-lane electromechanical actuator. The development process is repetitive and has to be modified as new elements are included or more sophisticated models are considered at different stages of the design. This chapter presents an overview of how this is achieved, by considering lumped and three-phase servo models driving inertial and aerodynamic loads.
-
5 Architecture consolidation
- + Show details - Hide details
-
p.
55
–69
(15)
This chapter introduces methods in achieving high integrity in the design of electric actuators, such as: output consolidation in multi-lane actuators; fault detection and fault isolation (FDI) system with embedded monitoring devices that conduct fault monitoring, voting, detection and isolation; two consolidation architectures and their associated FDI systems, namely, torque and velocity summing; a simulation graphical Monte Carlo (SGMC) method as a threshold setting technique; and lumped and three-phase lane models.
-
6 Hardware cross monitoring
- + Show details - Hide details
-
p.
71
–79
(9)
Fault tolerance is achieved through hardware redundancy in repeated hardware elements to provide protection against localised damage in safety-critical systems. Examples of such systems include aircraft, space vehicles, nuclear power plants and plants handling dangerous chemicals. One method in achieving fault detection and fault isolation is through hardware cross monitoring, where the performance of the repeated components is continuously assessed and compared. This technique is simple to apply and is widely used. The drawbacks include the extra hardware cost and the additional space required to accommodate the duplicated equipment. In this chapter, this technique will be presented to calculate the threshold values on a multi-lane actuator in torque and velocity summed architectures. The brushless dc motors in both architectures will be represented by their lumped models. The FDI system (discussed in Chapter 5) will be implemented to monitor the actuator for failures in feedback transducers as well as the currents in each lane.
-
7 Digital cross monitoring
- + Show details - Hide details
-
p.
81
–93
(13)
The previous chapter presented hardware cross monitoring in both architectures, and showed that the largest failure transients were motor failures related. Although the design met the aircraft response in roll, repeated hardware components in hardware cross monitoring necessitates for larger installation compartments. Therefore, this chapter proposes and compares digital cross monitoring (with a minimum of two lanes of repeated hardware) to hardware cross monitoring. Here, the hardware will be represented by three-phase equivalents and the digital mathematical model will be represented by the lumped model equivalent. The threephase hardware representation allows for detailed response examination in the presence of torque ripples contributed by the individual lanes. The Simulation Graphical Monte Carlo (SGMC) method will be implemented in this chapter too as a threshold setting technique.
-
Appendix 1: Hardware cross monitoring
- + Show details - Hide details
-
p.
95
–104
(10)
-
Appendix 2: Digital cross monitoring
- + Show details - Hide details
-
p.
105
–108
(4)
-
Back Matter
- + Show details - Hide details
-
p.
(1)