Hardware » History » Revision 12
Revision 11 (Luiz Fernando Lavado Villa, 2019-02-28 14:54) → Revision 12/15 (Luiz Fernando Lavado Villa, 2019-02-28 15:19)
h1. Hardware
{{>toc}}
The hardware of the single-phase project consists of a 10cm by 10cm printed circuit board that hosts 5 electronics blocks.
These blocks all fulfill functions which are necessary to the proper operation of any power electronics converter.
Figure 1 illustrates these blocks.
p=. {{thumbnail(theory_power_converter_1.png, size=350, title=General overview of a power electronics converter)}}
_Figure 1 - General overview of a power electronics converter_
Each block is explained in detail in the sections below.
h2. Power Block
To better explain the Power Block, this page splits its presentation in theory and practice.
h3. Theory
The theory of the power block is explained in the page below.
* [[Power Block Theory|Power Block Theory Page]]
h3. Practice
In practice The Power Block is the part that manages input/output power block is calculated to correspond to within the board.
It consists of a certain set of specifications.
The specifications are given single inverter leg, as illustrated in detail in the page figure below.
* [[Power Block Practice|Power Block Practice Page]]
In
p=. {{thumbnail(single_phase_topology.png, size=350, title=The power topology of the case single-phase board)}}
_Figure 2 - The power topology of the single-phase projects, board_
Figure 2 shows a Vlow, VHigh, T1, T2, D1, D2 and L.
Vlow is the specifications low-side voltage, VHigh is the high-side voltage, T1 and T2 are described by two transistors, D1 and D2 are two diodes and L is an inductor.
This topology is current bi-directional.
This means that its input can be either on the table below.
The Power Block high-side or on the low-side.
If the input is implemented in on the high-side, the circuit acts as a special page buck or step-down converter.
If the input is on the low-side, the circuit acts as a boost or step-up converter.
This topology allows the control of the KiCad project available current in the repository inductor L by controlling its charge and discharge using the switches.
The figure below shows the switching and the current flow within the inductor.
p=. {{thumbnail(states_converter_1.png, size=700, title=Current flow during switching)}}
_Figure 3 - The power topology of the single-phase project.
|_. Variable |_. Description |_. Value | board_
The switching leads to an average current flow between its input and output as shown in the image below.
p=. {{thumbnail(switching_states_1.png, size=700, title=Current flow during switching)}}
| Vlow | Maximum low-side voltage | 60 V | _Figure 4 - Left: average current in the inductor increases_
| Vhigi | Maximum high-side voltage| 120 V | _Center: average current in the inductor stable_
| freq | Switching frequency | 100 kHz | _Right: average current in the inductor decreases_
As figure 4 shows, the key to control the current in the power converter is to control the duration of the signal that is sent to the transistors.
This duration is called *duty cycle* .
| Pnom | Nominal A longer duty cycle will lead to a increase in current, while a shorter duty cycle will lead to a decrease in current.
The duty cycle is the single most important control variable in a power rating | 500 W |
With converter.
The presentation above is, obviously, not complete since there are further phenomena to be taken into account.
The instantaneous rise and fall in current will lead to abrupt variations in voltage at both the high and low sides.
To filter these specifications, variations, power converters are equipped with capacitors in both sides, which effectively provide the single-phase converter uses instantaneous current needed by the following components on it Power Block converter.
The relationship between high and low side voltages, high and low side currents, and the duty cycle is given by the equations below.
|_. Component |_. Description |_. Reference |_. RS Ref. | p=. !http://www.codecogs.com/eq.latex?\dfrac{V_{High}}{V_{Low}}=\dfrac{I_{Low}}{I_{High}}=\dfrac{1}{1-D}!
| ML1 | Low-side MOSFET transistor | FDPF39N20 | _Equation 1 - | Relation between High and Low variables, and the duty cycle for a Boost Mode operation_
p=. !http://www.codecogs.com/eq.latex?\dfrac{V_{High}}{V_{Low}}=\dfrac{I_{Low}}{I_{High}}=\dfrac{1}{D}! [1]
| MH1 | High-side MOSFET transistor| FDPF39N20 | _Equation 2 - |
| CPL1-4 | Low-side Capacitors | - | - |
| CPH1-4 | High-side Capacitors | - | - |
| L1 | Power Inductor | 1410478C | - |
| DL1 | Low-side Schottky Diodes | MBR20200 | - |
| DH1 | High-side Schottky Diodes | MBR20200 | - |
The MOSFET Relation between High and Low variables, and the Schottky diodes were chosen duty cycle for their a Buck Mode operation_
These equations explain the need for all the other blocks of the system.
To estimate the correct duty cycle, it is necessary to measure either voltage rating (200V) or current, leading to a measurement block.
Once these measurements are made, they must be converted in digital values, treated through a mathematical control loop and their current rating (30A - calculate the duty cycle value, leading to a control block.
Once the duty cycle has been correctly calculated, it must be confirmed).
The Capacitors were chosen for their converted in analog voltage rating, 160V - pulses which are in turn used to be confirmed. drive the transistors, leading to a driver block.
The Inductor was chosen for Since all of these operations require some energy, the Feeder block is thus needed to power all of the other blocks.
Each block has its current rating of 10 A.
own specific challenges and technical difficulties, which are explained in their respective wiki page.
h3. Practice
h2. Measurement Block
h2. Control Block
h2. Driver Block
h2. Feeder Block