**2. Matrix converter modulation and vector control**

Matrix converter consists of nine bidirectional switches arranged in 3 × 3 as shown in **Figure 4**. This is called all silicon solution [13]. The input phases (A, B, C) can be connected to output phases (a, b, c) for any switching period of time using bidirectional switches. The switches are controlled in such a way that the average output voltage is a sinusoidal waveform of the desired frequency and amplitude.

**57**

**2.1 Basic rules**

**Figure 4.**

basic rules have to be followed [13].

*The general structure of the conventional MC.*

1.No short circuit of two inputs

2.Never open circuit the outputs

space phasors) in various reference frames.

**2.2 Space vector modulation**

**2.3 Vector control**

The matrix converter consists of nine bidirectional switches with 29 (512) possible switching states. However, only 27 switching states can be used because two

Because of the above rules and also inductive loads nature of MC drive, each output line must always be connected to an input line. Under these basic rules, space

The space vector modulation (SVM) is defined as type of pulse width modulation (PWM) to generate gate drive signal to trigger the bidirectional switches (BDS) in MC [14]. SVM is also preferable to control and analyze machines with vector control (VC) or field oriented control of machines and allows visualization of the spatial and time relationships between the resultant current and flux vectors (or

Decoupling flux and torque is feature of VC to overcome sluggish torque response of Induction Motor (IM) to work like a separately excited DC machine. To achieve an independent control of the flux and torque, the direct axis (*d* axis) is aligned to a rotor flux vector (Ψ*r)* and the concept of the indirect field-oriented vector control (IFOVC) is depicted in **Figure 5** [15–17]. The rotating reference frame is rotating at synchronous angular velocity (ωe). The sensed three-phase output currents of MC

vector modulation (SVM) for MC drive has 27 switching states.

*Matrix Converter for More Electric Aircraft DOI: http://dx.doi.org/10.5772/intechopen.81056*

*Schematic of host drum drive system of TA.*

*Matrix Converter for More Electric Aircraft DOI: http://dx.doi.org/10.5772/intechopen.81056*

*Aerospace Engineering*

setup is connected in between input power supply and small input filter of MC. SCC method does not require additional components, which means that no separate RCC

The simulation results prove that the matrix converter is a suitable alternative to conventional HDDS converter topologies. The BDS method is experimentally adopted to verify the proposed concept by laboratory prototype matrix converter, which is built at Smiths Aerospace laboratory (later called GE Aviation laboratory) in University of Nottingham. This MEA project strongly supports the green environment by adopting abovementioned green technologies to obtain reduced aircraft

Matrix converter consists of nine bidirectional switches arranged in 3 × 3 as shown in **Figure 4**. This is called all silicon solution [13]. The input phases (A, B, C) can be connected to output phases (a, b, c) for any switching period of time using bidirectional switches. The switches are controlled in such a way that the average output voltage is a sinusoidal waveform of the desired frequency and

**2. Matrix converter modulation and vector control**

**56**

amplitude.

emissions.

**Figure 3.**

**Figure 2.**

*Tanker aircraft with RCC.*

is required to do the same action.

*Schematic of host drum drive system of TA.*

**Figure 4.** *The general structure of the conventional MC.*

## **2.1 Basic rules**

The matrix converter consists of nine bidirectional switches with 29 (512) possible switching states. However, only 27 switching states can be used because two basic rules have to be followed [13].


Because of the above rules and also inductive loads nature of MC drive, each output line must always be connected to an input line. Under these basic rules, space vector modulation (SVM) for MC drive has 27 switching states.

#### **2.2 Space vector modulation**

The space vector modulation (SVM) is defined as type of pulse width modulation (PWM) to generate gate drive signal to trigger the bidirectional switches (BDS) in MC [14]. SVM is also preferable to control and analyze machines with vector control (VC) or field oriented control of machines and allows visualization of the spatial and time relationships between the resultant current and flux vectors (or space phasors) in various reference frames.

#### **2.3 Vector control**

Decoupling flux and torque is feature of VC to overcome sluggish torque response of Induction Motor (IM) to work like a separately excited DC machine. To achieve an independent control of the flux and torque, the direct axis (*d* axis) is aligned to a rotor flux vector (Ψ*r)* and the concept of the indirect field-oriented vector control (IFOVC) is depicted in **Figure 5** [15–17]. The rotating reference frame is rotating at synchronous angular velocity (ωe). The sensed three-phase output currents of MC

**Figure 5.** *Field orientation: Ψr is aligned with d-axis.*

drive are converted into stationary reference frame (isα, isβ) and then viewed as two "dc" quantities (isd, isq). The direct axis or real axis component is responsible for the field producing current (isd) and is ideally maintained constant up to the motor synchronous speed. If d-axis is aligned with rotor flux vector (Ψ*r*), the system is said to be field oriented. The q-axis component is responsible for torque producing current (isq). These two vectors are orthogonal to each other so that the field current and torque current can be controlled independently [16–17].
