Overvoltage protection system and method

A method of operating an electrical system of an engine having an alternator system that is configured to supply alternating current (AC) power to a remainder of the electrical system, the method comprising:

• rectifying the AC power supplied by the alternator system and communicating the rectified AC power to a terminal at which are coupled both of a battery and a load, wherein the electrical system includes a silicon-controlled rectifier employed for performing the rectifying, and wherein the electrical system additionally includes a transistor device that at least indirectly influences operation of the silicon-controlled rectifier;
• experiencing an overvoltage event at which a first voltage exceeds a threshold, wherein the first voltage is either a terminal voltage at the terminal or an other voltage based at least indirectly upon the terminal voltage;
• causing the communicating of the rectified AC power to the terminal to cease, at least partly in response to the experiencing of the overvoltage event, wherein the electrical system is configured so that, when the first voltage exceeding the threshold is provided from the alternator system or from one or more other external sources connected to the electrical system, the electrical system operates to protect one or more electrical components on a system power line by isolating the alternator system;
• charging a capacitor at least in part as a result of energy received due to the overvoltage event;
• and
• delaying a reestablishment of the communicating of the rectified AC power to the terminal until at least a predetermined time period has elapsed since the overvoltage event, wherein the predetermined time period is based at least in part upon a resistance of a resistor and a capacitance of the capacitor that discharges through the resistor following a conclusion of the overvoltage event, wherein the reestablishment of the communicating of the rectified AC power occurs upon the capacitor being sufficiently discharged so as to result in a switching of a status of the transistor device, and
• wherein, prior to the overvoltage event, the communicating of the rectified AC power additionally ceases during a time period in response to a second voltage exceeding a battery charge set point and subsequently is reestablished.

An electrical system for use with an alternator system that supplies electrical power, the electrical system comprising:

• a first circuit portion configured to govern whether the electrical power is communicated from the alternator system to a terminal associated with both of a battery and a load;
• a second circuit portion configured to determine whether a voltage is elevated above a predetermined threshold and to provide a first signal upon determining that the voltage is elevated above the predetermined threshold such that an overvoltage condition has occurred, wherein the voltage is either a first voltage at the terminal or a second voltage based at least indirectly upon the first voltage;
• and
• a third circuit portion coupled at least indirectly to each of the first and second circuit portions, wherein the third circuit portion includes at least one comparator circuit portion configured to make a determination as to whether an additional voltage is below or equal to a charge set point,
• wherein the third circuit portion is configured to provide a second signal for receipt by the first circuit portion upon receiving the first signal from the second circuit portion,
• wherein the third circuit portion also is configured to provide the second signal for receipt by the first circuit portion upon the determination being made by the at least one comparator circuit portion that the additional voltage is not below or equal to the charge set point,
• wherein the second signal is additionally configured to cause the first circuit portion to cease allowing communication of the electrical power to the terminal, and
• wherein the electrical system is configured so that, when the voltage that is elevated above the predetermined threshold is provided from the alternator system or from one or more other external sources connected to the electrical system, the electrical system operates to protect one or more electrical components on a system power line by isolating the alternator system.