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--- lab:ninjascc:hardware [2016/03/12 23:35] – chrono
+++ lab:ninjascc:hardware [2016/03/25 20:23] – chrono
@@ Line 1: / Line 1: @@
-====== NinjaSCC Hardware ======
+====== NinjaSCC Hardware Design Specifications ======
 {{:lab:ninjascc:ninjascc.sch.svg|}}
-# Design Specifications
-Desired NinjaSCC Specs to have a guideline during design phase.
+Desired NinjaSCC Specs to have a common frame of reference during design and
+documentation phase.
-| Symbol           | Parameter                  | Min  | Typ  | Max  | Unit |
+===== Electrical =====
-|:----------------:|:--------------------------:|:----:|:----:|:----:|:----:|
-| V<sub>MPP</sub>  | PV MPP Voltage             | 5    |      | 45   | V    |
-| V<sub>OC</sub>   | PV Open-Circuit Voltage    |      |      | 50   | V    |
-| I<sub>SC</sub>   | PV Short-Circuit Current   |      |      | 15   | A    |
-| P<sub>MPP</sub>  | PV Power                   |      |      | 250  | W    |
-| V<sub>Out</sub>  | Output Voltage             | 0    |      | 28   | V    |
-| I<sub>Out</sub>  | Output Current             |      |      | 12.5 | A    |
-| OVP              | Overvoltage Protection     |      |      | 45   | V    |
-| OTP              | Overtemperature Protection |      | 125  |      | °C   |
-| MPP<sub>Eff</sub>| MPP Efficiency             |      | 98.5 |      | %    |
-| PM<sub>Eff</sub> | Panel-Mode Efficiency      |      | 99.5 |      | %    |
+==== PV Input ====
-### Input
+^                   Symbol                    ^         Parameter          ^  Min   ^  Typ  ^  Max  ^  Unit   ^
+|  V<html><sub></html>MPP<html></sub></html>  |       PV MPP Voltage       |  11.5  |  18   |  36   |    V    |
+|  V<html><sub></html>OC<html></sub></html>   |  PV Open-Circuit Voltage   |        |       |  45   |    V    |
+|  I<html><sub></html>SC<html></sub></html>   |  PV Short-Circuit Current  |        |       |  15   |    A    |
+|  P<html><sub></html>MPP<html></sub></html>  |        PV MPP Power        |        |       |  250  |    W    |
+|                      -                      |  Panel/Cell Configuration  |   18   |  36   |  72   |  Cells  |
-| Parameter            | Value    | Unit  |
+==== Battery ====
-|:--------------------:|:--------:|:-----:|
-| Input Configuration  | 36 or 72 | Cells |
-| Max. Input Voltage   | 45       | V     |
-| Max. Input Current   | 20       | A     |
-| Cont. Input Current  | 10       | A     |
-### Battery Output
+^                      Symbol                      ^      Parameter      ^  Min  ^  Typ   ^  Max  ^  Unit  ^
+|    V<html><sub></html>Bat<html></sub></html>     |   Charge Voltage    |   5   |  13.4  |  45   |   V    |
+|    I<html><sub></html>Bat<html></sub></html>     |   Charge Current    |       |        |  15   |   A    |
+|  Ripple<html><sub></html>rms<html></sub></html>  |  Output Ripple RMS  |       |   15   |       |   mV   |
+|  Ripple<html><sub></html>p-p<html></sub></html>  |  Output Ripple P-P  |       |   40   |       |   mV   |
-| Parameter            | Value    | Unit  |
+NinjaSCC will by default fall into a 12V system. Any other check, charge,
-|:--------------------:|:--------:|:-----:|
+equalize and float setpoints can easily be overriden in software to leave
-| Output Configuration | 12-24    | V     |
+more headroom for all kinds of use-cases and many battery types like lead-acid,
-| Max. Input Current   | 20       | A     |
+gel,agm and lithium battery packs in the 12V to 36V range.
-| Cont. Input Current  | 10       | A     |
-### Load Output
+Output Current/Voltage ripple and RF noise need to be kept at a minimum, to
+increase battery lifetime and allow RF sensitive devices, like remote
+SDRs, to be powered by NinjaSCC as well.
-| Parameter            | Value    | Unit  |
+==== Load ====
-|:--------------------:|:--------:|:-----:
-| Cont. Output Current | 10       | A     |
-## Environment
+^                    Symbol                    ^       Parameter        ^  Min  ^  Typ  ^  Max  ^  Unit  ^
+|  V<html><sub></html>Load<html></sub></html>  |     Output Voltage     |   5   |       |  45   |   V    |
+|  I<html><sub></html>Load<html></sub></html>  |  Cont. Output Current  |       |       |  15   |   A    |
-| Parameter            | Value    | Unit  |
+==== Efficiency ====
-|:--------------------:|:--------:|:-----:|
-| Min. Temperature     | -40      | °C    |
-| Max. Temperature     | +85      | °C    |
-## PCB
+^                      Symbol                       ^          Parameter          ^  Min  ^  Typ   ^  Max  ^  Unit  ^
+|  BK-MPP<html><sub></html>Eff<html></sub></html>   |  Buck-Mode MPP Efficiency   |       |  98.5  |       |   %    |
+|  BST-MPP<html><sub></html>Eff<html></sub></html>  |  Boost-Mode MPP Efficiency  |       |  98.5  |       |   %    |
+|    TR<html><sub></html>Eff<html></sub></html>     |     Transit Efficiency      |       |  99.5  |       |   %    |
-| Parameter            | Value    | Unit  |
+==== ADC ====
-|:--------------------:|:--------:|:-----:|
-| Material             |  FIXME   |  -    |
-| Layers               |  2       |  -    |
-| PCB Thickness        |  2       |  mm   |
-| Copper               |  70      |  µm   |
-| Silkscreen           |  White   |  -    |
-| Soldermask           |  Black   |  -    |
+-bit ARef 5V (Arduino)
+-bit ARef 5V (4 channel external ADC via I2C)
-When the optimal operating condition falls into a narrow window
+===== Environment =====
-that Vin and Vout are within about ±2% of each other, the panel mode is engaged to take the advantage
-of the almost lossless energy harvest feature. In panel mode as shown in Figure 6, Q5A/B remains ON
-while the DC/DC converter shuts down, establishing a direct link between the PV panel output and the
-string.
-When the panel mode is not the optimal operating condition, the MPPT/PM controller will turn-off PM
+^  Symbol  ^          Parameter           ^  Min  ^  Typ  ^  Max  ^  Unit  ^
-switches and engage the DC/DC converter for maximum power tracking. In a conventional Buck-and-
+|   Temp   |    Operating Temperature     |  -40  |  25   |  85   |   °C   |
-Boost converter, switching of the diagonal switches is synchronized. Namely Q1 and Q3 are turned on
+|   OTP    |  Overtemperature Protection  |       |  +85  |       |   °C   |
-and off at the same time. So are Q2 and Q4.
+|   OVP    |    Overvoltage Protection    |       |       |  45   |   V    |
-NinjaSCC has four operating modes:
+===== PCB =====
-  * Buck-Only (BK)
+^   Parameter    ^   Value   ^
-  * Boost-Only (BST)
+|     Layers     |     2     |
-  * Buck-Boost-Interleaved (BB)
+|   Thickness    |   2 mm    |
-  * Bypass (BP)
+|     Copper     |   70 µm   |
+|   Silkscreen   |   White   |
+|   Soldermask   |   Black   |
+|  Substrate HQ  |  P96/P26  |
+|  Substrate MQ  |   IS410   |
+|  Substrate LQ  |    FR4    |
+===== Protection =====
+==== Electrical ====
+  * Short-Circuit [HW]
+  * Over-Voltage [HW+SW]
+  * Over-Current [HW+SW]
+  * Adjustable Current Limiter [HW+SW]
+  * LVD (Low-Voltage Disconnect of Load) [SW]
+  * UVLO (Under-Voltage Lock-Out) [HW]
+  * Uncontrolled Back-Channel DC GND return (High-Side Load Switch) [HW]
+  * Electromagnetic and Lightning induced extraneous Voltage Transients [HW]
+  * Local ESD [HW]
+==== Environmental ====
+  * Battery Temperature Monitoring (via external 100k thermistor)
+  * PV Panel Temperature Monitoring (optional)
+  * PCB Temperature Monitoring
+  * Over-Temperature controlled Shutdown
+  * Fan-Control
+  * Assembly PU-Coating
+===== Modes of Operation =====
 Based on real-time assessment of the operating conditions, NinjaSCC dynamically
@@ Line 85: / Line 101: @@
 of the PV panel, keeping overall conversion efficiency close to 99%.
+  * MPP Tracking Buck-Only (BK)
+  * MPP Tracking Boost-Only (BST)
+  * MPP Tracking Buck-Boost-Interleaved (BB)
+  * Transit (TR)
+===== Controller =====
+Since Arduinos have been around for a while and have a very broad
+spectrum of documentation, HOWTOs and open-source code to learn from, the
+AVR ATMega32U4 8-Bit Microcontroller (with built-in USB support so that
+we can [[https://hackaday.com/tag/ftdigate/|give FTDI the finger]]) was
+chosen as the main controller in a fully Arduino-Micro compatible
+configuration, while adding a couple of protective features to it.
+This way, NinjaSCC can be used and flashed over USB like any other
+Arduino-Micro board.
+===== Dedicated USB Charging Port (DCP) =====
+As other USB power sources, like most wall warts and auto adapters,
+NinjSCC does not enumerate the USB output port. Charging can begin
+immediately, without any digital communication/negotiation, as defined
+in the supplementary USB Battery Charging Specification, Rev 1.1,
+/15/2009 (BC1.1).
+  * Supply 5V up to 1.5A
+  * DCP mode identified by a short between D+ to D-
+  * Short-Circuit, Over-Voltage, Over-Current, Over-Temperature protected
+  * Shares EN pin with Load Switch to maintain LVD ability by default,
+but can be selected with a solder bridge/0R
+===== Monitoring & Metrics =====
+Constantly monitor and collect all relevant system metrics and operating
+parameters and deliver a high-resolution, real-time metrics stream
+over USB to be live-viewed and/or shipped into a metrics storage engine
+like [[https://github.com/influxdata/influxdb|influxdb]] to achieve full
+real-time, remote system awareness, gather long-term data to optimize
+the system even further and have a means to analyze/identify sub-optimal
+operating conditions which might lead to failure like: Battery temperatures
+that are consistently above ambient may indicate high ripple, overcharging
+or internal cell shorting.
-Generally, when the PV panel’s Vmpp is lower than about 98% of Vout defined in Equation 2, the
+===== Remote Control =====
-controller will run the converter in the BK mode. Figure 7a shows the equivalent circuit of BK mode, where
-only Q1 and Q2 are switching, while Q3 remains OFF and Q4 stays ON.
-When the PV panel’s Vmpp is greater than about 102% of the output voltage defined in Equation 2, the
-controller will run the converter in the BST mode. Figure 7b shows the equivalent circuit of BST mode.
-Only Q3 and Q4 are switching, while Q2 remains OFF and Q1 stays ON.
+Any DC/DC regulation parameter can be overriden in software by remote
+controlling NinjaSCC over USB, so playing and experimenting on a live,
+working converter with instant metric feedback will be a great opportunity
+to study its behaviour while changing parameters and operating modes
+manually. And of course, a fun and hands-on learning assistance while
+teaching buck/boost technology to others.
+===== Resilience =====
-## Protection
+Designed in a built-to-last approach, almost all components have been
+selected in a range between automotive qualified and up to
+aerospace/military grade quality. A non-profit approach is the key here,
+because this way the focus gets back where it should belong: On the
+product and the component quality it is made of. With attention to detail
+and without undue compromise.
-### ESD
+To further decrease the chance of total system failure, most important
+system blocks and components have been set up n+1 redundant, wherever
+possible and reasonable.
-Input/Output lines can be subjected to extraneous voltage induced or directly connected - such as Electrostatic discharge (ESD). The circuitry itself should be designed to withstand the voltage. Special components
+NinjaSCC must withstand gale force sub-arctic winds at -40°C while still
-are available to do this and it is also possible to supplement the protection with Spark Gaps which can also be fabricated cheaply, as a trace pattern on a PCB.
+providing power to the camera you’ve put out there for over a year,
+to make a movie about glacier calving or you are in a remote desert at
++55°C ambient temperature and need power to operate your water pump.
+When you’re truely off-grid, this is the device that must not fail
+(or at last reasonably max out the chance that it does), because murphy
+dictates: it usually does so at the worst possible point in time.
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