Control system for a heating system and method for operating a heating system

Patent metadata

Field	Value
Publication number	US-11433735-B2
Application number	US-202016823495-A
Country	US
Kind code	B2
Filing date	Mar 19, 2020
Priority date	Mar 20, 2019
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

A control system and method for a heating system of an electric vehicle or hybrid vehicle is embodied such that when there is a heating request for a high-voltage accumulator, an HVA heating mode is activated in which the high-voltage accumulator which is connected to an HVA circuit of the heating system is heated by an HVA heating source which is activated for this purpose so that heat is generated in the HVA circuit or transferred into the circuit. When there is a heating request for a passenger compartment of the vehicle, an air-conditioning heating mode is activated in which the passenger compartment is heated by a heating circuit, with heat which is generated in the heating circuit with an auxiliary heater or is transferred into the heating circuit with a heat pump, or both. When the air-conditioning heating mode is activated, it is determined whether or not there is a heating deficit which indicates whether the heating request can be completely satisfied with the auxiliary heater or with the heat pump or with both. If there is a heating deficit, an auxiliary heating mode is activated in which heat of the HVA heating source is transferred from the HVA circuit into the heating circuit by the heat pump in order to compensate the heating deficit.

First claim

What is claimed is:

1. A system for a heating system of an electric vehicle or hybrid vehicle, comprising:
a control system configured to execute a process such that:
when there is a heating request for a high-voltage accumulator (HVA), an HVA heating mode is activated in which the high-voltage accumulator, which is connected to an HVA circuit of the heating system, is heated by an HVA heating source which is activated for said purpose so that heat is generated in the HVA circuit or transferred into said HVA circuit,
when there is a heating request for a passenger compartment of the vehicle, an air-conditioning heating mode is activated in which the passenger compartment is heated, by a heating circuit, with heat which is generated with an auxiliary heater in the heating circuit or is transferred into the heating circuit with a heat pump, or both,
when an air-conditioning heating mode is activated, determining whether there is a heating deficit which indicates whether or not the heating request can be satisfied completely with the auxiliary heater or with the heat pump or with both,
if there is a heating deficit, an auxiliary heating mode is activated in which heat of the HVA heating source is transferred from the HVA circuit into the heating circuit by the heat pump in order to compensate the heating deficit.

2. The system according to claim 1 , wherein the control system is further configured such that:
it is determined that there is a heating deficit if a difference between a heating circuit actual temperature in the heating circuit and a heating circuit set point temperature exceeds a maximum difference.

3. The system according to claim 1 , wherein the control system is further configured such that:
it is determined that there is a heating deficit if a difference between a set point heating capacity and a potential heating capacity exceeds a maximum difference, wherein the set point heating capacity is determined on the basis of the heating request, and the potential heating capacity is determined on the basis of a respective maximum heating capacity of the auxiliary heater and of the heat pump.

4. The system according to claim 1 , wherein the control system is further configured such that:
the auxiliary heating mode is activated in a delayed fashion, wherein when there is a heating deficit the auxiliary heating mode is not activated until a waiting time has elapsed.

5. The system according to claim 1 , wherein the control system is further configured such that:
the capacity of a refrigeration circuit of the heating system is closed-loop controlled with a compressor closed-loop controller which uses as a manipulated variable a compressor rotational speed of a compressor in the refrigeration circuit and to which a heating circuit actual temperature of the coolant in the heating circuit is fed as a closed-loop control variable and a heating circuit set point temperature is fed as a guide variable,
and the compressor closed-loop controller is used irrespective of whether or not the auxiliary heating mode is activated in the air-conditioning heating mode.

6. The system according to claim 5 , wherein the control system is further configured such that:
the compressor closed-loop controller is limited in the auxiliary heating mode in that the compressor rotational speed of the compressor is limited in accordance with a coolant actual temperature in the HVA circuit downstream of the chiller so that the refrigeration capacity of the chiller is limited.

7. The system according to claim 1 , wherein the control system is further configured such that:
an expansion valve is closed-loop controlled with a valve closed-loop controller which uses as a manipulated variable an opening of the expansion valve upstream of a chiller of the heat pump in a refrigeration circuit of the heat system and to which an actual overheating value in the refrigeration circuit is fed as a closed-loop control variable, and a set point overheating value is fed as a guide variable, and that the valve closed-loop controller is used irrespective of whether or not the auxiliary heating mode is activated in the air-conditioning heating mode.

8. The system according to claim 7 , wherein the control system is further configured such that:
the refrigeration capacity of the chiller is limited in the auxiliary heating mode in that the set point overheating value is extracted from a characteristic diagram in accordance with a coolant actual temperature in the HVA circuit downstream of the chiller.

9. The system according to claim 7 , wherein the control system is further configured such that:
the refrigeration capacity of the chiller is limited in the auxiliary heating mode in that the opening of the expansion valve is reduced as the coolant actual temperature in the HVA circuit downstream of the chiller rises.

10. The system according to claim 1 , wherein the control system is further configured such that:
when the auxiliary heating mode and the HVA heating mode are activated simultaneously, the heat pump is actuated in such a way that its efficiency is set in such a way that the extraction of heat from the HVA circuit is limited and the heating deficit is nevertheless compensated.

11. The system according to claim 1 , wherein the control system is further configured such that:
the HVA heating source is activated if the auxiliary heating mode or the HVA heating mode is active or both are active, and is closed-loop controlled with a heating closed-loop controller to which a heating capacity of the HVA heating source is fed as a manipulated variable and to which a coolant actual temperature in the HVA circuit upstream of the high-voltage accumulator is fed as a closed-loop control variable, and a coolant set point temperature is fed as a guide variable.

12. The system according to claim 1 , wherein the control system is further configured such that:
in the air-conditioning heating mode and when the auxiliary heating mode is inactive, the heat pump is activated in order to heat the passenger compartment, and residual heat is extracted from the coolant in the HVA circuit, wherein the residual heat occurs as excess heat in the HVA circuit as a result of the fact that the coolant actual temperature upstream of the high-voltage accumulator is higher than a cell temperature of the high-voltage accumulator.

13. The system according to claim 1 , wherein
the HVA heating source is an HVA auxiliary heater which is connected to the HVA circuit downstream of the heat pump.

14. The system according to claim 13 , wherein the HVA auxiliary heater is an electric continuous flow heater.

15. The system according to claim 1 , wherein
the HVA heating source is a trimmed electric machine of the vehicle.

16. A method for operating a heating system of an electric vehicle or hybrid vehicle via a control system, the method comprising:
when there is a heating request for a high-voltage accumulator (HVA), activating an HVA heating mode in which the high-voltage accumulator which is connected to an HVA circuit of the heating system is heated by an HVA heating source which is activated for this purpose so that heat is generated in the HVA circuit or is transferred into said circuit,
when there is a heating request for a passenger compartment of the vehicle, activating an air-conditioning heating mode in which the passenger compartment is heated by a heating circuit, with heat which is generated with an auxiliary heater in the heating circuit, or is transferred into the heating circuit with a heat pump, or both,
when the air-conditioning heating m

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Allgaeuer Christian
• Christ Paul
• Horn Oliver
• Moser Dominik
• Oswald Patrick
• Siuka Andreas

Classifications

• B60H1/00278

  for the battery · CPC title

• B60H2001/00307

  Component temperature regulation using a liquid flow · CPC title

• B60H1/00385 Primary

  for vehicles having an electrical drive, e.g. hybrid or fuel cell · CPC title

• B60H2001/00949

  comprising additional heating/cooling sources, e.g. second evaporator · CPC title

• B60H1/00007

  Combined heating, ventilating, or cooling devices (control systems or mechanisms B60H1/00642) · CPC title