There are 3 mutual methods of charging a battery; constant voltage, constant electrical flow as well as a combination of constant voltage/constant electrical flow amongst or without a smart charging circuit.
Constant voltage allows the total electrical flow of the charger to period of time into the battery until the ability provide reaches its pre-set voltage. The electrical flow volition as well as hence taper downward to a minimum value 1 time that voltage score is reached. The battery tin terminate hold upward left connected to the charger until ready for occupation as well as volition stay at that “float voltage”, trickle charging to compensate for normal battery self-discharge. A typical instance would a depression toll automobile battery charger for habitation occupation or basic dorsum upward ability systems. This method enables fast charging rates as well as is suitable for Pb acid types, but non for Nickel Metal Hydride (Ni-MH) or Lithium-Ion (Li-ion) types.
Constant current is a elementary cast of charging batteries, amongst the electrical flow score laid at around 10% of the maximum battery rating. Charge times are relatively long amongst the disadvantage that the battery may overheat if it is over-charged, leading to premature battery replacement. This method is suitable for Ni-MH type of batteries. The battery must hold upward disconnected or a timer business office used 1 time charged.
Constant voltage / constant current (CVCC) is a combination of the higher upward ii methods. The charger limits the amount of electrical flow to a pre-set score until the battery reaches a pre-set voltage level. The electrical flow as well as hence reduces equally the battery becomes fully charged. This organisation allows fast charging without the risk of over-charging as well as is suitable for Li-ion as well as other battery types.
Smart charging involves the occupation of a micro-controller to compensate for temperature ascent as well as conform the accuse electrical flow as well as accuse fourth dimension accordingly to the battery specifications. This extends battery life as well as is used amongst Li-ion battery types. This battery administration circuit or unit of measurement tin terminate hold upward fitted externally to the charger. A expose of the ability semiconductor manufacturers offering command circuits to perform this function.
An instance of a CVCC charger is the TDK-Lambda EVS series. The output voltage as well as the accuse electrical flow tin terminate hold upward laid yesteryear ii potentiometers as well as the output characteristics are shown below. The transition betwixt constant voltage as well as constant electrical flow is automatic.
As an example, catch a 24V battery organisation (with a maximum float voltage of 28V) as well as discharged downward to 15V.
When the discharged battery (at 15V) is connected to the ability supply, the battery volition get-go to accuse at the pre-set constant electrical flow level. The electrical flow volition stay constant until the voltage rises to 28V. At this indicate the ability provide volition transition to constant voltage means as well as the electrical flow volition decay to nix when the battery is fully charged.
The accuse electrical flow is controlled to avoid overheating as well as the float voltage express to avoid over-charging.
A typical application for the EVS existence used amongst a battery administration unit of measurement is shown below.
Under normal conditions, when air conditioning is present, the electronic switch would hold upward unopen as well as air conditioning would hold upward connected straight to the terminate equipment. The EVS ability provide volition accuse the battery via the battery administration unit of measurement as well as transition to constant voltage means when complete. In the resultant of an air conditioning ability interruption, the switch would connect the battery as well as DC/AC inverter to the terminate equipment. If the ability time out was extensive as well as the battery was to approach a fully discharged condition, the switch would isolate the battery to avoid a damaging deep discharge.
The EVS ability provide tin terminate hold upward used amongst the EVS-RP module to avoid the battery discharging into the ability provide when the air conditioning provide is non present, or nether a error condition.
EVS300, EVS600 as well as EVS-RP Module
No comments:
Post a Comment