Scattered bypass and concentration of modular UPS bypass scheme comparison and analysis
Scattered bypass and concentration of modular UPS bypass solution analysis of modular UPS, as the name implies, is the high-power UPS system, separated into many sub modules in parallel, through the optimization of system control, realizes the system expansion and online upgrade, maintenance, and greatly improve the system reliability, availability, and energy saving effect, reduce the maintenance cost of customers in recent years has gradually become the mainstream of choice for customers.
Separate bypass architecture bypass architecture, that is, each power module contains rectifier and inverter and battery, and other parts, also contains equal static bypass capacity and power module, can be thought of as a UPS without LCD monitor.
Multiple modules of parallel system in the cabinet, interrelationship between module is similar to traditional weaver UPS system.
Switch to bypass the power supply system, the load by all scattered bypass to parallel power supply in the power module.
Bypass architecture centralization bypass architecture, that is, only one system and the system capacity is equal to the concentration of the bypass module, power module contains only within the rectifier and inverter and battery conversion circuit, by an independent controller in every part, the parallel between modules is no longer the traditional UPS weaver system, but contains complex inverter, bypass flow control and monitoring logic.
Scattered bypass scheme has the advantage of simple control, development difficulty is small, only to the original UPS weaver system transplant and optimize the monitoring part;
Rack the cost is low;
Bypass device for small capacity, costs are relatively low;
How much static bypass road redundancy.
Bypass solution concentration is developed after scattered bypass technical route, compared with the traditional weaver UPS system, from logic control flow, system coordination, fault tolerant ability to do the very big change.
1, the difference of the performance of the two plans under steady-state conditions, the bypass power supply, bypass solution concentration is only offer a bypass all current, maximum capacity to bypass capacity according to the system design, has nothing to do with the number module configuration.
Scattered bypass solution is made up of multiple small power static bypass to bear the load, due to the bypass circuit is low resistance circuit, multi loop method of flow there is no way to use the software to control, flow between modules depends entirely on the following factors: (1) the differences between individual components, mainly conducting the difference of pressure drop, the dispersion of device manufacturer is inevitable;
(2) the loop impedance differences, mainly is the cable length of each circuit cannot be guaranteed, and the cable connection point impedance due to grasp the process control, etc.
2, scattered bypass system reliability analysis can be claimed is the bypass redundancy, the advantages of centralized bypass is considered there is a single point of failure, please see the following analysis.
From the Angle of the device on the analysis from the Angle of the device, the reliability of a single large power SCR is far higher than the system composed of numerous small devices, concentrated bypass module function is simple, only need to consider the effect of devices and a small amount of peripheral driving circuit, and scattered bypass for distribution within the power module, at the same time affected by modules within a multitude of devices.
From the perspective of system capacity on analysis from the Angle of system capacity, concentrated bypass capacity according to the cabinet design, has nothing to do with the number of module configuration.
And scattered bypass static bypass capacity is determined by module capacity, when the module failure, system will lose the corresponding static bypass capacity.
A more extreme example, when two power module rack configuration, if the load rate is about 55%, when a module fault, remaining a module will be at 110% overload condition, the end result is the system off the electricity.
Same condition for concentrated bypass, completely is not a problem.
Concentrated bypass module for device capacity advantage, and even some manufacturers offer 125% long-term overload ability, it has absolute security for system reliability.
From a centralized bypass the reliability design of the reliability design and analysis of centralized bypass, many mainstream manufacturers are also put forward a lot of improve the reliability of the program, such as the redundancy backup scheme of control circuit, communication bus redundancy scheme, power module and the bypass module control decoupling scheme, power module in the bypass control scheme, the solution of each manufacturer have distinguishing feature each, after years of market validation, can greatly improve the system availability, add the bypass module is hot plug design, easy upgrades maintenance and power module.