Table of Contents

Power: Source

Description

A power source class is a component that can provide power to a network. It can be a fixed amount or dynamic, such as a solar panel or an external power source connected to an external connector. The power source can be connected to the power bus in series or parallel networks, providing voltage and current to the network based on the configured power. Power sources can also function in isolation, simply calculating the power based on the controlled functionality.

Example Use Cases

  • Providing Power: Powering a circuit with voltage and current that can change over time.
  • Charging Batteries: Being able to charge a battery with a constant or variable inflow of current.

Module Implementation

A power source is a component that inherits from the Physical Object class and can produce power to a power network. It contains a Nominal Voltage, which is the specified voltage that the source will be producing, provided that the power is non-zero. This is defaulted to 12 volts. Additionally, along with Power that can be configured, in watts, the Is Active flag can specify if the power is provided to the network.

Internal Components

The power source functionality consists of three components; an internal resistor, a voltage source and a current source (if providing and controlling the current). The resistance is a fixed value, usually defaulted to 1 Ohm of power. However, if the source is Forward-Biased, then the resistance will be set to a maximum value, essentially acting as a diode. This will prevent the power source from drawing current and voltage from the power network when not providing power. If the power source should not include a diode functionality, then this Boolean can be disabled on the power source.

The voltage source provides a DC voltage equal to the Nominal Voltage unless the calculated power is zero, in which case the DC voltage will be set to 0.

The current source sets the DC current equal to the power law, where:

\[ I_\mathrm{DC} = {P \over V_\mathrm{nominal}} \]

If the Control Current Boolean is disabled, then the power source will not add an internal current source and will rely on the power bus's network to control and determine the current of the power source.

Assumptions/Limitations

  • Unless connected to a power bus, a power source will not automatically power other components or charge a battery on a spacecraft.
  • The power source will act with a diode functionality unless specified otherwise. This will prevent the current or voltage from being drawn by a source when the power is zero.