A very important aspect of any home renewable energy system is the charge controller. Charge controllers are connected into a wind turbine system between the source of power generation (such as a wind turbine or a solar panel) and the electricity storage system, usually a chemical battery such as lithium ion batteries. The charge controller monitors and controls voltage levels of the electricity flowing to the battery to ensure the battery is not overloaded. In the event that excess electricity is generated, the charge is dissipated through a dump component such as a heating element or an electrical resistor. All in all this device ensures that the electricity generated is managed effectively, efficiently and safely and prevents your wind turbines from damaging your battery storage systems.
Types of Charge Controllers
There are a few different types of charge controllers commonly used in domestic settings, each have their own benefits and drawbacks:
Shunt Controller: This is the most basic type of controller. The controller is switched on when batteries can be charged and switched off when the batteries are full. The simplicity of this device makes it the cheapest option but at the cost of the system being very inefficient.
Series Regulator: These devices are similar in concept to the Shunt Controllers. Series Regulator controllers divert power through different pathways to achieve different electrical results depending on the state of the batteries. This is most commonly used in large solar arrays as it is a cheap method of controlling battery voltage with better efficiency than Shunt Controllers.
Pulse Width Modulation: Pulse Width Modulation charge controllers constantly monitor the power levels of the batteries in the system and allow the required charge through, with different modes depending on how full the batteries are. These systems are generally quite efficient and relatively cheap so are a popular option for homeowners installing a small solar array on their property.
Maximum Power Point Tracking: This charge controller type manages the voltage and the current of the electrical flow to ensure the power generation and storage is optimised. By optimising the power, this charge controller can potentially significantly increase solar panel productivity. As with the other above types, this kind of charge controller is best suited to solar panels due to their smooth voltage DC power production.
Diversion Load: This type of charge controller diverts excess power into an electrical dissipating component such as a resistor to prevent the power from overcharging and damaging the batteries. This type of charge controller is popular in wind turbine charge controllers due to the suprratic nature of the voltage generated by wind turbines as a result of inconsistent wind speeds. For this reason, TESUP chooses to use a Diversion Load system to produce its charge controllers.
Solar and wind Charge Controllers
Certain charge controller types are better suited to either solar or wind power generators. Solar panels generate a smooth DC voltage which can be managed efficiently by a charge controller calibrated to operate within a small range as the power generation from solar panels is predictable. Wind turbines spin when wind pushes them and as a result can generate power in a wide range of voltages depending on weather conditions. Wind turbine charge controllers therefore must be able to operate over a large range of voltages to incorporate peak voltages resulting from strong gusts of wind.
Wind turbine charge controllers also require a safety braking system to stop the wind turbine from spinning too quickly and causing damage to itself and its surroundings. This is achieved in TESUP turbines through the Diversion Load system and adds an extra layer of safety to the turbine. The most efficient option for choosing a charge controller for a domestic power generation system with multiple renewable sources such as wind and solar is generally to use individual charge controllers for each renewable energy generator. It is inefficient for a single charge controller to handle both inputs as the different generators produce power in different ranges of voltage.
Updates on TESUP Charge Controller
It is a top priority of TESUP’s to develop safe and effective charge controllers, committing to the constant innovation and development of TESUP products. In striving for this kind of innovation, a TESUP engineer spotted a potential improvement to the existing charge controllers. The previously mentioned electrical component responsible for the ‘dump’ load could be
improved! The existing component relied on a wire based resistor to dissipate the electricity: a coil of wire through which electrical current is passed, heating up the wire and dissipating the electricity.
Unfortunately, when the wire heated up significantly under continuous dumping of electricity the wire had the potential to lose its structural integrity and start to sag and deform. As the wire was live with electricity, any contact with other metallic components could cause a safety hazard. The sagging could cause the wires to contact other ‘dump’ resistors or potentially the case of the charge controller, causing electricity to flow into the wrong areas and developing a safety hazard. This is understandably an issue that could be resolved to make TESUP charge controllers even better and more effective!
To improve the charge controller system, instead of the wire resistor, a ceramic core resistor has been implemented. Ceramic materials have the benefit of having a very good strength under hot conditions. This means under high temperature conditions the material will not deform or move. Implementing a core of ceramic material with the resistor wire wrapped around the core creates a ceramic resistor and allows for safer operation. With the ceramic core in place the wire can no longer sag or deform so the wire stays exactly where it s expected to.
Protection of the overall electrical system from overcharging is one of the most important features a charge controller provides. This is another area in which TESUP engineers have placed their focus to ensure the most safety conscious system is used. Highly developed Printed Circuit Boards or ‘PCBs’ are used in TESUP charge controllers to ensure efficient and safe operation. These PCBs provide clearly defined electrical pathways which allows the proper transmission of electricity through the system. With each iteration of the TESUP charge controller the newest technology in PCB systems is integrated ensuring a safe and efficient device.
Have a look at the ever developing TESUP charge controller production line to see some of the inner workings of a TESUP charge controller and see some of the PCBs that could be going into a charge controller coming to you!
You can really see the dedication of TESUP to innovation and improvement through their actions rather than just words. TESUP looks to continue to improve its products every day to make a safer and more efficient world.