Electric power has become increasingly important in the defense industry. Almost everything in the military is now powered by electricity. As such, both the quality and quantity of electric power needed have gone up.
Power supplies have become crucial to defense operations. They ensure that the power delivered to devices has constant power characteristics, which avoids problematic issues like overvoltage and overvoltage. Uninterruptible power supplies ensure that even when there are power outages or other problems, mission-critical systems continue to be powered.
Electrical systems in defense applications have to be highly reliable, durable, and efficient. Power supplies used in the military have to go for long without maintenance. At the same time, failure is not an option in some cases as it can result in significant consequences like a defense system being rendered useless.
In addition, electrical systems in the military are exposed to harsh conditions, usually for prolonged periods. These include extreme temperatures, heavy vibration and shock, corrosive sea environments, and dust.
For the reasons above, power supplies used in defense have to be specially made. Normal power supplies don’t have the high performance, reliability, and durability for military applications.
Defense power supplies have to be ruggedized to endure harsh weather and other extreme conditions. They also have to conform to the MIL-STD family of military standards.
A power supply that is ruggedized and that conforms to the relevant military standards is called a MIL power supply.
Such supplies are made by companies that specialize in military power equipment like generators, power converters, and uninterruptible power supplies. An example of such companies is Titan Power Systems.
Types of Defense Power Supplies
Given the task of supplying power solutions, defense contractors have two main options. They can opt for Commercial Off-The-Shelf (COTS) products or for custom-made products.
To know which option to go for, there are a number of factors to consider. These include budgetary constraints and the presence of unique requirements.
Commercial Off-The-Shelf
Usually, due to budgetary constraints, most contractors opt for COTS military power supplies. These are off-the-shelf products that are designed to meet military standards and that are ruggedized for military use. They are suitable but have some disadvantages when compared to customized products.
In addition, in some scenarios, available COTS options may not fit the particular application that is being implemented. This can happen for a variety of reasons. It can be that the power characteristics required for a certain load can’t be reliably achieved. It can also be a problem with form factors, for example size or packaging.
Custom-Made
Whatever the case, the contractor has to approach a company that makes custom military power supplies – such as Titan Power Systems – and place an order for a custom-made MIL power supply product.
If a client opts to go for custom-made solutions, there are a couple of options to choose from.
The power supplies can be slightly modified. This happens when there’s only a small change to be made.
They can also be fully customized. This happens when there are a number of changes to be made, touching on both form factors and function.
Procuring custom-made power supplies is expensive and it can take a long time before the products are delivered. However, the customization can help achieve high performance and ensure the product is perfectly suited for its application.
The time-to-market problem is usually mitigated by assembling building blocks to produce the custom power supplies faster.
Military Standards That Defense Power Supplies Must Conform To
There are a range of military standards that power supplies have to conform to if they are to be used in the military.
These cover different use-cases. For example, there is a set of standards specified for ship-board electronics and another specified for ground-vehicle electronics.
However, there are some standards that apply across groups. For example, there is a set of standards that specifies the testing procedures that all military equipment should go through.
Below are examples of military standards.
MIL-STD-1275
This standard defines immunity requirements and test conditions to be satisfied when dealing with spikes, operating voltages, ripple, and surges. The requirements ensure that military electrical devices remain reliable despite the above-mentioned power events.
It defines operating limits for different ground vehicle modes, including normal operating mode, generator-only mode, and starting mode.
Compliance with this standard is usually left to the user to determine. For example, if a surge causes a device to fail, then the device could be rendered unfit. Conversely, if the surge results in a higher level of ripple during the susceptibility test, then the device could be considered fit.
MIL-STD-704
This standard specifies the acceptable power delivered to electrical equipment used in aircraft military applications. It defines the requirements for the operation, compatibility, power usage and testing for both single-phase and three-phase grounded neutral systems.
The considerations that should be made to ensure compliance with this standard include maximum distortion, standard voltage limits, undervoltage conditions, and input transient handling.
