solar_sat.py

import datetime
import math

# Constants
SOLAR_CONSTANT = 1361  # Solar irradiance in W/m^2
BATTERY_CAPACITY = 10000  # Battery capacity in Watt-hours (Wh)
SOLAR_ARRAY_EFFICIENCY = 0.3  # Efficiency of solar panels
TRANSMISSION_EFFICIENCY = 0.9  # Efficiency of power transmission

# Global state
battery_charge = 4000  # Initial battery charge in Wh
consumption_log = []  # Log of power consumption (Wh)

def calculate_solar_power(solar_array_area, sunlight_hours, angle_to_sun):
    """Calculate solar power generated, accounting for angle to the sun."""
    effective_irradiance = SOLAR_CONSTANT * math.cos(math.radians(angle_to_sun))
    effective_irradiance = max(effective_irradiance, 0)  # No negative irradiance
    generated_power = (
        effective_irradiance * solar_array_area *
        SOLAR_ARRAY_EFFICIENCY * sunlight_hours * TRANSMISSION_EFFICIENCY
    )
    return generated_power  # Wh

def log_consumption(subsystem, power, duration):
    """Log power consumption for a subsystem."""
    global battery_charge
    consumed_energy = power * duration  # Wh
    consumption_log.append({
        'subsystem': subsystem,
        'power': power,  # W
        'duration': duration,  # hours
        'energy': consumed_energy,  # Wh
        'timestamp': datetime.datetime.now()
    })
    battery_charge -= consumed_energy

def balance_energy(solar_array_area, sunlight_hours, angle_to_sun):
    """Balance energy generated and consumed."""
    global battery_charge
    generated_power = calculate_solar_power(solar_array_area, sunlight_hours, angle_to_sun)
    battery_charge += generated_power

    # Ensure battery charge stays within valid range
    battery_charge = max(0, min(battery_charge, BATTERY_CAPACITY))

    return generated_power

def report_status():
    """Report current power system status."""
    print(f"Battery charge: {battery_charge:.2f} Wh")
    print("Recent Consumption Log:")
    for log in consumption_log[-5:]:  # Last 5 logs
        print(f"- {log['subsystem']} consumed {log['energy']:.2f} Wh ({log['duration']} hours)")

# Example Usage
if __name__ == "__main__":
    solar_array_area = 2  # m^2 for CubeSat
    sunlight_hours = 5  # Example: 5 hours of sunlight
    angle_to_sun = 30  # Angle between solar panel normal and sunlight in degrees

    # Calculate energy generation
    generated_power = balance_energy(solar_array_area, sunlight_hours, angle_to_sun)
    print(f"Solar power generated: {generated_power:.2f} Wh")

    # Log power consumption
    log_consumption("Communications", power=150, duration=3)  # 150 W for 3 hours
    log_consumption("Payload Operations", power=200, duration=2)  # 200 W for 2 hours
    log_consumption("Thermal Control", power=50, duration=5)  # 50 W for 5 hours

    # Report current status
    report_status()

    # Simulate eclipse period (no sunlight)
    eclipse_hours = 2
    generated_power = balance_energy(solar_array_area, eclipse_hours, angle_to_sun=90)  # Sun blocked
    print(f"Solar power generated during eclipse: {generated_power:.2f} Wh")

    # Report final status
    report_status()