MycilaPulseAnalyzer

License: MIT Continuous Integration PlatformIO Registry

ESP32 / Arduino Library to analyze pulses from a Zero-Cross Detection circuit and manage the Zero-Cross pulse.

Features

This library is used in YasSolr Solar Router to detect Zero-Cross pulse and control the Thyristor / TRIAC with many supported ZCD modules.

Supported ZCD Circuits

More hardware are supported, as long as they fall into one of these categories above.

 

Usage

Mycila::PulseAnalyzer pulseAnalyzer;

static void ARDUINO_ISR_ATTR onEdge(Mycila::PulseAnalyzer::Event e, void* arg) {
  if (e == Mycila::PulseAnalyzer::Event::SIGNAL_RISING || e == Mycila::PulseAnalyzer::Event::SIGNAL_FALLING) {
    digitalWrite(PIN_OUTPUT, HIGH);
    delayMicroseconds(OUTPUT_WIDTH_US);
    digitalWrite(PIN_OUTPUT, LOW);
  }
}

static void ARDUINO_ISR_ATTR onZeroCross(void* arg) {
  digitalWrite(PIN_OUTPUT, HIGH);
  delayMicroseconds(OUTPUT_WIDTH_US);
  digitalWrite(PIN_OUTPUT, LOW);
}

void setup() {
  Serial.begin(115200);
  while (!Serial)
    continue;

  pinMode(PIN_OUTPUT, OUTPUT);

  pulseAnalyzer.onEdge(onEdge);
  pulseAnalyzer.onZeroCross(onZeroCross);

  pulseAnalyzer.begin(35);
}

Output:

{"state":0,"period":9994,"period_min":9975,"period_max":10014,"frequency":100.0600357,"width":1168,"width_min":1154,"width_max":1182}
{"state":0,"period":9993,"period_min":9976,"period_max":10018,"frequency":100.0700455,"width":1166,"width_min":1154,"width_max":1180}

IRAM Safety

You can run the app with:

-D CONFIG_ARDUINO_ISR_IRAM=1
-D CONFIG_GPTIMER_ISR_HANDLER_IN_IRAM=1
-D CONFIG_GPTIMER_CTRL_FUNC_IN_IRAM=1
-D CONFIG_GPTIMER_ISR_IRAM_SAFE=1
-D CONFIG_GPIO_CTRL_FUNC_IN_IRAM=1

This will improve interrupt reliability (they will continue working even during flash operation).

MycilaPulse makes use of inline function of HAL layer and ARDUINO_ISR_ATTR to ensure that the interrupt handlers are in IRAM.

You can look at teh examples in the project to see how to use this library with IRAM safety.

Zero-Cross event shift

Compile flag -D MYCILA_PULSE_ZC_SHIFT_US is used to control the shift of the Zero-Cross event.

By default, the value is set to -150 us, which means that the Zero-Cross event is shifted by - 150 us from the middle of the pulse (or start of the front edge in the case of the BM1Z102FJ chip).

The shift can also be configured with:

For the JSY-MK-194

MYCILA_JSY_194_SIGNAL_SHIFT_US is used to compensate the signal shift of the JSY-MK-194, because the JSY will detect the Zero-Cross event ~ 100 us after the actual zero. The JSY-MK-194T detection happens after 1000 us.

You can also use the getters and setters:

pulseAnalyzer.setJSY194SignalShift(100); // For JSY-MK-194G
pulseAnalyzer.setJSY194SignalShift(1000); // For JSY-MK-194T

Oscilloscope Views

Here are below some oscilloscope views of 2 ZCD behaviors with a pulse sent from an ESP32 pin to display the received events.

Robodyn

Here are some views of the Robodyn ZC pulse, when adding a 1 us pulse on each event: rising and falling, and a 1us pulse on the ZC event, with -D MYCILA_PULSE_ZC_SHIFT_US=0.

Here is the same view, but after applying a shift of about 100 us to the ZC event:

Zero-Cross Detector from Daniel S

Here are some views of the ZC pulse, when adding a 1 us pulse on each event: rising and falling, and a 1us pulse on the ZC event with -D MYCILA_PULSE_ZC_SHIFT_US=0.

Here is the same view, but after applying a shift of about 100 us to the ZC event:

BM1Z102FJ chip based ZCD

Oscilloscope view of the BM1Z102FJ chip based ZCD where each pulse match the positive component of the AC voltage.

Oscilloscope view with edge detection activated

Oscilloscope view with default Zero-Cross event with -D MYCILA_PULSE_ZC_SHIFT_US=-100 (shifted by -100 us), which is teh default.

Oscilloscope view with default Zero-Cross event (shifted by -200 us)

Oscilloscope view with default Zero-Cross event (shifted by 200 us)

JSY-MK-194

This library also supports the Zx pin of the JSY-MK-194G (JSY-MK-194T and other JSy boards probably supported, but untested), which is a ZC pulse of 20 ms.

View of the JSY-MK-194G Zero-Cross pulse on a 5 ms / div oscilloscope. The pulse width is 20 ms on a 50 Hz AC voltage.

View of the JSY-MK-194G Zero-Cross pulse on a 100 us / div oscilloscope. The blue lines represent the edge detection and the Zero-Cross event (shifted 100-150 us before zero).

You can also have a look at MycilaJSY to control the JSY-MK-194G.

Use-Case: Thyristor TRIAC Control

You can look at the example in the project how to use this library to control a Thyristor / TRIAC with a zero-cross detection circuit.

Use-Case: Know when the AC voltage is positive or negative

The BM1Z102FJ has a positive pulse when the AC voltage is positive, and a negative pulse when the AC voltage is negative.

Thanks to MycilaPulseAnalyzer, you can know when the AC voltage is positive or negative by using the onEdge callback and check if it is a rising or falling edge.

Readings

Here is a blog post explaining how to use this library, with some oscilloscope screenshots:

https://yasolr.carbou.me/blog/2024-07-31_zero-cross_pulse_detection.