High efficiency hydronic circulator with sensors
A highly efficient circulator system is provided, useful for hydronic systems, including both heating and cooling systems. The stand-alone circulator motor is controllable by input from certain sensors, preferably thermal sensors, which provide data enabling the controller of the brushless pump motor to vary its flow output to meet changes in systems loads. The circulator has a ceramic permanent magnet rotor, such as a ferrite, with an electronically, preferably sinusoidally, commutated, electro-magnetic stator controlling the input of electrical power.
1. A fully enclosed, stand-alone, wet rotor circulator system for a recirculating hydronic fluid system designed to be located within a space to be heated or cooled, wherein the wet rotor circulator system is designed to move hydronic fluid through the recirculating hydronic fluid system, the wet rotor circulator system comprising:
a wet rotor circulator, comprising:
a centrifugal impeller,
an electrically powered, variable frequency DC motor, the variable frequency DC motor being operationally connected to the centrifugal impeller to drive the centrifugal impeller;
the electrically powered, variable frequency DC motor comprising a permanent magnet rotor formed of at least one ferrite ceramic magnet, and a system of stator coils configured to be powered by a sinusoidally variable DC current;
an electronic control system electrically connected to the system of stator coils of the variable frequency DC motor, the electronic control system comprising:
a printed circuit board comprising:
a rectifier configured to rectify an AC line current to a non-stepped down, rectified DC current, the AC line current providing an AC line voltage in the range of from about 110 Volts to about 250 Volts, the non-stepped down, rectified DC current, being provided at a non-stepped down DC voltage of from about 160 Volts to about 350 Volts, dependent upon the voltage of the AC line current,
circuitry for receiving electrical thermal data signal from at least one thermal sensor, and
an electrical circuit connection on the rectifier to connect the rectifier to a source of AC current at the AC line voltage;
an electronic commutation system designed to form a sinusoidally variable frequency DC current output and having an electrical connection to the rectifier to receive the non-stepped down DC current output from the rectifier; and
an electronic, variable frequency drive (“VFD”) including:
an electrical connection to the electronic commutation system to receive the sinusoidally variable frequency DC current output,
an electrical connection to the system of stator coils of the variable frequency DC motor, and
an electronic connection for receiving the electrical thermal data signal from the at least one thermal sensor via the printed circuit board,
wherein the VFD comprises a microcontroller configured to interpret the electrical thermal data signal received from the at least one thermal sensor; and
wherein the VFD is configured to provide power to the system of stator coils and the microcontroller is configured to control, via the VFD, a motor speed of the variable frequency DC motor by varying the frequency of the sinusoidally variable, non-stepped-down DC current powering the system of stator coils of the variable frequency DC motor in response to the electrical thermal data signal received from the at least one thermal sensor, thereby controlling the flow of the hydronic fluid through the recirculating hydronic fluid system to maintain a predetermined temperature within the space to be heated or cooled.
2. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 1 , wherein the permanent magnet rotor is formed of a plurality of ferrite ceramic magnets.
3. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 2 , wherein each of the plurality of ferrite ceramic magnets is an anisotropic ferrite ceramic magnet.
4. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 3 , wherein the plurality of anisotropic ferrite ceramic magnets are formed into a Halbach array.
5. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 1 , wherein the recirculating hydronic fluid system is configured to be located within a residential building which defines the space to be heated or cooled.
6. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 5 , wherein the VFD is configured to maintain a designated temperature within the residential building by responding to the electrical thermal data signal from the at least one thermal sensor.
7. The stand-alone, wet rotor circulator system for the recirculating hydronic fluid system of claim 5 , wherein the recirculating hydronic fluid system is configured to work with a boiler located within the residential building, and wherein the VFD is configured to prevent the hydronic fluid from returning to the boiler below a predetermined temperature.
8. The stand-alone, wet rotor circulator for the hydronic system of claim 1 , wherein the recirculating hydronic fluid system is connected to a cooling system comprising liquid flow ducts for chilled liquid, wherein air is blown past the liquid flow ducts in the recirculating hydronic fluid system containing chilled liquid, and further comprising an air supply heat sensor monitoring the temperature of the air that has blown past the ducts in the recirculating hydronic fluid system containing the chilled liquid.