grid connect inverters nuer 19 basic principles. what is an inverter? a solid state device which...
TRANSCRIPT
![Page 1: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/1.jpg)
Grid Connect InvertersNUER 19
Basic Principles
![Page 2: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/2.jpg)
What is an Inverter?
• A Solid State Device which main job is to convert a Direct Current Supply to an Alternating Current Supply
• Inverter Symbol
![Page 3: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/3.jpg)
An Inverter converts this Direct Current Input Wave Shape
To this Alternating Current Output wave shape
![Page 4: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/4.jpg)
By using many very high speed switching devices an inverter is able to convert a series of precise D.C. Pulses
into a synthesised A.C. Wave shape
![Page 5: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/5.jpg)
Inverter Principle of Operation
• Basically a 4 way switching bridge is used to re-route the direct current to alternate it at a set frequency through the load.
![Page 6: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/6.jpg)
The Roles of a Grid Connect Inverter
To convert D.C. from the generating source Photovoltaic Array or Wind Turbine etc into an A.C. Wave that is then transformed and synchronised with the electricity grid
May Provide galvanic (voltage) isolation between the D.C. side and A.C. sides
To extract the maximum amount of energy from the generating source Called Maximum Power Point Tracking (MPPT)
To log and display electrical data from the array such as Energy, Power Voltage Current, $ Income & CO2 offset
System monitoring and protection over: current, temperature & voltageEarth fault & arc fault detection etc
![Page 7: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/7.jpg)
System Diagram
![Page 8: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/8.jpg)
Basic Portable Inverter Circuit with MOSFET’s and Centre Tap Transformer
![Page 9: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/9.jpg)
Block Diagram for Typical Grid connect Inverter
![Page 10: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/10.jpg)
Internal Inverter Components
• Switching Devices Transistors MOSFET’s/IGBT’s• Double Wound Transformer • Diodes• Thermistor’s • Surge diverter MOV’s• Fuses • Filtering Inductors and Capacitors
![Page 11: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/11.jpg)
PN Junction Diodes
Diodes are semi conductor devices consisting of a PN Junction the P is the anode and the N is the cathode. When a positive charge is placed on the anode & negative is place on the cathode the diode conducts and is said to be forward biased. If a negative is placed on the anode and positive on cathode the diode is said to be reverse biases and the diode will not conduct
AnodeCathode
![Page 12: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/12.jpg)
Bridge Rectifier Converts A.C. Supply in to Basic D.C. Supply
Input wave shape
Output wave shape
Symbol
Bridge Rectifier
Bridge Rectifier
![Page 13: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/13.jpg)
MOSFET TransistorMetal Oxide Semi Conductor Field Effect Transistor
• Two N type semi Conductors within a P type base
• When the gate is pulsed positive a electron bridge is created and current can flow through the source and drain.
MOSFET symbol
![Page 14: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/14.jpg)
MOSFET’s N channel & P channel
![Page 15: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/15.jpg)
IGBTInsulated Gate Bipolar Transistor
The insulated-gate bipolar transistor or IGBT is a three-terminal power semiconductor device, noted for high efficiency and fast switching. It switches electric power in many modern appliances: electric cars, variable speed refrigerators, air-conditioners, and even stereo systems with digital amplifiers. Since it is designed to rapidly turn on and off, amplifiers that use it often synthesize complex waveforms with pulse width modulation and low-pass filters.
![Page 16: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/16.jpg)
Double Wound Transformer
Used for stepping the input voltage up or down providing galvanic isolation and helps with smoothing out the sin wave
![Page 17: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/17.jpg)
Types of Wave Shapes of Inverters
• Square Wave • No voltage regulation, cheap and nasty, limit to type of
appliances that can be run off it
• Modified Square Wave voltage • Still a square wave except the voltage is Regulated by
Pulse Width Modulation (PWM)
• True Sin wave (PWM with filters) less than 5% total Harmonic Distortion
![Page 18: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/18.jpg)
Types of Waves (Continued)
![Page 19: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/19.jpg)
Pulse Width Modulation to create a True Sine Wave
Pulse width modulation is a technique used to create sinusoidal wave from a series of coded D.C. pulses called a pulse train. For the pulse train to become Smooth like a true sin wave a capacitive inductive filter must be used.
![Page 20: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/20.jpg)
Classifying Grid Connect Inverters
• Method of Commutation– Line Commutated– Self Commutated
• Transformer/ Transformerless • How P.V. Array and Inverter Interface
– Modular (at the modules)– String Inverter– Multi String– Mini Central – Central
![Page 21: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/21.jpg)
Line Commutated Inverters
Using a thyristor Bridge arrangement the thyristor’s are switched (commutated)By alternated pulses from the grid.These are known as grid controlled inverters and when the grid falls these inverter will automatically stop
![Page 22: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/22.jpg)
Self Commutated Inverters
Same Principle as Stand Alone Inverters Using Pulse width modulation switching devices are MOSFET’s or IGBTMust be used with a Grid Protection Device To ensure safety of the line workers when the grid goes down.
![Page 23: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/23.jpg)
Transformer Classifications Based on Transformers
• Low Frequency Transformer (Safe, reliable, lowest efficiency very heavy) Galvanic Isolation
![Page 24: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/24.jpg)
HF Inverters• High Frequency Transformer (Galvanic Isolation, no
iron Core, Tx very light and more efficient than Low Frequency Tx more complicated electronics)
![Page 25: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/25.jpg)
Transformerless Grid Connect Inverters• No Tranformer (transformerless) (No galvanic
isolation cheap to build most efficient has some serious safety concerns)
![Page 26: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/26.jpg)
Safety Concerns with Transformerless Inverters
![Page 27: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/27.jpg)
Specification Sheet SMA Sunny Boy
![Page 28: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/28.jpg)
Efficiency Curve
![Page 29: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/29.jpg)
Classification by interfaceString Inverters
Most common type
![Page 30: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/30.jpg)
Multi String Inverter
Dual MPPT so that two completely separate arrays can be inputed into the inverter with no efficiency consequences .Can have East West Facing Arrays
![Page 31: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/31.jpg)
Central Inverters
• Used for Large Solar Farms/Parks where the solar access is uniform across the park
![Page 32: Grid Connect Inverters NUER 19 Basic Principles. What is an Inverter? A Solid State Device which main job is to convert a Direct Current Supply to an](https://reader035.vdocuments.net/reader035/viewer/2022070306/551663b9550346a2698b5287/html5/thumbnails/32.jpg)
List the Advantages and Disadvantages of Central Inverter over Multiple string Inverters