Jon Freeman / Mbed 2 deprecated Alternator2020_06

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Dependencies:   mbed BufferedSerial Servo2 PCT2075 I2CEeprom FastPWM

field.h@5:6ca3e7ffc553, 2020-12-05 (annotated)

Committer:
JonFreeman
Date:
Sat Dec 05 12:40:17 2020 +0000
Revision:
5:6ca3e7ffc553
Parent:
3:43cb067ecd00 
Code for 'Smart Regulator' to August 2020, published as is. Basic low-level functions all thoroughly tested and debugged, top level algorithms have scope for further development - over to you! For help contact jon @ jons-workshop[.com

Who changed what in which revision?

UserRevisionLine numberNew contents of line
JonFreeman 3:43cb067ecd00 1 #include "mbed.h"
JonFreeman 3:43cb067ecd00 2 /**
JonFreeman 3:43cb067ecd00 3 Functions to control alternator field
JonFreeman 3:43cb067ecd00 4 */
JonFreeman 3:43cb067ecd00 5
JonFreeman 3:43cb067ecd00 6
JonFreeman 3:43cb067ecd00 7 /**void set_pwm (double d) { Range 0.0 to 1.0
JonFreeman 3:43cb067ecd00 8 This PWM used to limit max duty ratio of alternator field energisation.
JonFreeman 3:43cb067ecd00 9 With R25=33k and C4=100n controlling ramp input to CS pin of MCP1630 (not MCP1630V),
JonFreeman 3:43cb067ecd00 10 ramp terminates fet 'on' pulse after a max of approx 980 us.
JonFreeman 3:43cb067ecd00 11 With const int PWM_PERIOD_US = 2000 , duty ratio is thus limited to approx 50% max.
JonFreeman 3:43cb067ecd00 12 This is about right when using 12V alternator on 24V systems
JonFreeman 3:43cb067ecd00 13 A 1.225V reference (U7) is fed to the MCP1630 error amp which compares this to fed-back proportion of system voltage.
JonFreeman 3:43cb067ecd00 14 This adjusts final PWM down to zero % as needed to maintain alternator output voltage.
JonFreeman 3:43cb067ecd00 15 */
JonFreeman 3:43cb067ecd00 16
JonFreeman 3:43cb067ecd00 17 class FieldControl {
JonFreeman 3:43cb067ecd00 18 uint8_t privatemadetab[440];
JonFreeman 3:43cb067ecd00 19 uint64_t t_on, t_off, measured_pw_us, measured_period, rise_count, fall_count;
JonFreeman 3:43cb067ecd00 20 uint32_t old_percent;
JonFreeman 3:43cb067ecd00 21 PwmOut pwm_osc_in; // Controller PWM driving MCP1630
JonFreeman 3:43cb067ecd00 22 InterruptIn V_ext; // Connected to MCP1630 output to MOSFET
JonFreeman 3:43cb067ecd00 23 void VextRise (); // Handles - MCP1630 has just turned mosfet on
JonFreeman 3:43cb067ecd00 24 void VextFall (); // Handles - MCP1630 has just turned mosfet off
JonFreeman 3:43cb067ecd00 25 public:
JonFreeman 3:43cb067ecd00 26 FieldControl (PinName pwmoscin, PinName vext) ; // Constructor
JonFreeman 3:43cb067ecd00 27 void set_pwm (double); // What it says, 0.0 to 1.0 but inverts to suit MCP1630
JonFreeman 3:43cb067ecd00 28 void maketable ();
JonFreeman 3:43cb067ecd00 29 uint32_t set_for_speed (uint32_t rpm);
JonFreeman 3:43cb067ecd00 30 double get_duty_ratio () ;
JonFreeman 3:43cb067ecd00 31 } ;
JonFreeman 3:43cb067ecd00 32