Method for dynamically reducing peak electromagnetic interference from a group of switching devices connected on a communications bus

A system for reducing a peak electromagnetic interference produced by each switching device of a group of switching devices connected to a communications bus, the system comprising:

• a controller having a microprocessor and a non-transitory memory associated with the microprocessor, the non-transitory memory storing an algorithm for implementation by the microprocessor and characteristics of the switching devices and/or loads controlled by the switching devices;
• a fixed range of frequencies, the fixed range of frequencies including frequencies emitted by each switching device in the group of switching devices during normal operation;
• a subrange of frequencies associated with each switching device in the group of switching devices, each subrange of frequencies being dynamically determined by the characteristics of its associated switching device and/or the load control led by its associated switching device, the characteristics being indicated by a weight, which can be a binary value or a numeric value associated with one or both of a static characteristic of the switching device and/or the load controlled by the switching device or a dynamic characteristic of the switching device and/or the load controlled by the switching device, the microprocessor configured by the algorithm to continuously update the characteristics of each switching device and/or load, and further configured by the algorithm to dynamically adjust the frequency of the subrange of frequencies associated with each switching device based on the weights of the updated characteristics;
• and
• a timer associated with each switching device, the timer configured to use a maximum and a minimum frequency of the subrange of frequencies associated with its associated switching device to spread the peak frequency of that associated switching device over its associated subrange of frequencies.

A method for dynamically reducing a peak electromagnetic interference produced by a group of switching devices connected to a common communications bus, the method comprising:

• determining a fixed range of frequencies, the fixed range of frequencies including frequencies emitted by each switching device in the group of switching devices during normal operation;
• determining, by a microprocessor, a subrange of frequencies associated with each switching device in the group of switching devices, each subrange of frequencies being dynamically determined by one or more characteristics of its associated switching device and/or a load controlled by its associated switching device, the characteristics being indicated by a weight, which can be a binary value or a numeric value associated with one or both of a static characteristic of the switching device and/or the load controlled by the switching device or a dynamic characteristic of the switching device and/or the load controlled by the switching device;
• and
• spreading a peak frequency of each switching device over its associated subrange of frequencies by a timer associated with the switching device and using a maximum and a minimum frequency of the associated subrange of frequencies;
• and
• repeating continuously, by the microprocessor, determining the subrange of frequencies associated with each switching device in the group of switching devices and spreading, by the timer, the peak frequency of each switching device over its associated subrange of frequencies.