Pump Control Unit (PCU) for adaptive, flow-mechanically optimized control of circulation pumps in heating and heat pump systems

Abstract

Pump control system for heating systems with heat pump, comprising at least one primary circuit pump and at least one secondary circuit pump, characterized in that a central Pump Control Unit (PCU): • detects the volume flows reported by the pumps via wired or wireless bus interfaces, • regulates the volume flow of the secondary circuit pump so that it does not exceed the volume flow of the primary circuit pump, • and avoids both return flow mixing in the heating circuit and flow of supply water into the generator return in the primary circuit.

Description

1. Technical field The invention relates to the control and coordination of circulation pumps in heating systems, particularly in systems with heat pumps and one or more heating circuits. It relates to a central control unit (“Pump Control Unit”, PCU) that evaluates the flow rates of modern circulation pumps, balances them, and thereby prevents return flow mixing in the heating circuit and overflow in the primary circuit. The PCU can communicate with pumps, sensors, and system controllers both via wired and wireless connections. 2. State of the art In modern heating systems with heat pumps, primary and secondary pumps often operate independently. Modern circulation pumps can determine their flow rate internally and report it via bus interfaces. Nevertheless, typical problems arise: • Return flow mixing in the heating circuit when the secondary flow rate is greater than the primary flow rate, leading to a reduction in the flow temperature. • Overflow in the primary circuit when heating circuit water is forced into the generator return, reducing the efficiency of the heat pump. • Lack of coordination between primary and secondary pumps. • Destruction of the hydraulic balancing when pumps regulate independently. • Lack of system intelligence to collectively evaluate the flow rates of multiple pumps. • Lack of integration into system controllers or building automation. The current state of the art does not include a central unit that records and coordinates the flow rates of multiple pumps via wired or wireless bus systems while simultaneously preventing backflow mixing and overflow. 3. Object of the invention The object of the invention is to provide a system that: • detects the volume flows of all pumps involved, • prevents return flow mixing in the heating circuit, • avoids overflow in the primary circuit, • maintains hydraulic balancing, • communicates with pumps, sensors and system controllers both wired and wirelessly, • in particular supports LIN bus, • can process analog signals such as 0-10 V or PWM, • and optionally uses learning optimization methods. 4. Solution to the task The task is solved by a Pump Control Unit (PCU) with the following features: 1. Communication interfaces that support both wired bus systems (in particular LIN bus, CAN bus, Modbus) and wireless communication protocols. 2. Measurement of the flow rates of all connected pumps, whereby the pumps determine their flow rate internally and report it via the interfaces. 3. Control of the secondary flow rate so that it does not exceed the primary flow rate. 4. Prevention of return flow mixing in the heating circuit by limiting the secondary flow rate. 5. Prevention of overflow in the primary circuit by limiting the secondary flow rate or adjusting the primary pump output. 6. Implementation of Δp or ΔT control in the heating circuit within the limits defined by the primary flow rate. 7. Coordination of multiple parallel secondary pumps, whereby the sum of the flow rates is limited. 8.Communication with a system controller to receive operating states, temperature values, or setpoints, or to send status information back. 9. Processing of analog signals, especially 0-10 V or PWM, for integrating older pumps or external sensors. 10. Optional learning optimization unit that evaluates historical operating data and adaptively adjusts control parameters. 5. Examples of Implementation 5.1 Communication The PCU communicates with pumps, sensors and system controllers via: • LIN bus, • CAN bus, • Modbus, • wireless communication protocols, • analog signals such as 0-10 V or PWM. The PCU absolutely requires the reported flow rates of the pumps. 5.2 Avoidance of return flow mixing The PCU monitors the secondary volume flow and limits it so that it does not exceed the primary volume flow. 5.3 Prevention of overflows The PCU detects overflows in the primary circuit based on the volume flow ratios and limits the secondary volume flow or requests an adjustment of the primary pump output. 5.4 Hydraulic balancing Within the volume flow limits, the PCU regulates Δp or ΔT in the heating circuit. 5.5 Learning Optimization (optional) The PCU can: • recognize patterns in the volume flow curves, • adaptively adjust control parameters, • proactively select operating modes. 6. Advantages of the invention • Prevents backflow mixing and overflow • Maintains hydraulic balancing • Utilizes modern pumps with flow rate monitoring • Operates wired and wirelessly • Supports LIN bus • Can process analog signals • Reduces installation errors • Increases efficiency and operational reliability • Optionally adaptive and self-optimizing Reference symbol list 1 Heat generator (heat pump / boiler) 2 Primary circuit pump (internal / external) 3 Buffer tank / hydraulic separator 4 Secondary circuit pump (external) 5 Heating circuit (underfloor heating / radiators) 6 Heating system control 7 Pump control PCU (internal or external) 8 Storage tank temperature sensors 9 Flow rate sensor (internal / external)

Claims

Pump control system for heating systems with heat pump, comprising at least one primary circuit pump and at least one secondary circuit pump, characterized in that a central Pump Control Unit (PCU): • detects the volume flows reported by the pumps via wired or wireless bus interfaces, • regulates the volume flow of the secondary circuit pump so that it does not exceed the volume flow of the primary circuit pump, • and avoids both return flow mixing in the heating circuit and flow of supply water into the generator return in the primary circuit. PCU according to claim 1, characterized in that the PCU uses the primary volume flow rate as a control variable. PCU according to one of the preceding claims, characterized in that the PCU communicates with pumps and sensors via LIN bus, CAN bus, Modbus or wireless communication protocols. PCU according to one of the preceding claims, characterized in that the PCU exclusively considers pumps that determine and report their volume flow internally. PCU according to one of the preceding claims, characterized in that the PCU detects return flow mixing in the heating circuit and prevents it by limiting the secondary volume flow. PCU according to one of the preceding claims, characterized in that the PCU detects overflows in the primary circuit and prevents them by adjusting the pump power. PCU according to one of the preceding claims, characterized in that the PCU performs Δp or ΔT control in the heating circuit. PCU according to one of the preceding claims, characterized in that the PCU coordinates several parallel secondary pumps. PCU according to one of the preceding claims, characterized in that the PCU takes into account special operating conditions of the heat pump and allows temporary deviations. PCU according to one of the preceding claims, characterized in that the PCU communicates with a system controller and receives operating states, temperature values ​​or setpoints or sends back status information. PCU according to one of the preceding claims, characterized in that the PCU can process analog input signals, in particular 0-10 V or PWM signals. PCU according to one of the preceding claims, characterized in that the PCU comprises a learning optimization unit that automatically adjusts control parameters based on historical operating data or recognized patterns. PCU according to one of the preceding claims, characterized in that the PCU selects predictive control strategies to anticipate load peaks, defrosting processes or user behavior. PCU according to one of the preceding claims, characterized in that the PCU implements hysteresis or deadband control to avoid oscillation.

Images