Apparatus comprising an inverter

Patent metadata

Field	Value
Publication number	US-12583335-B2
Application number	US-202418419701-A
Country	US
Kind code	B2
Filing date	Jan 23, 2024
Priority date	Feb 28, 2023
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

The present disclosure relates to an apparatus comprising a controller, an inverter, a load and a DC link. The DC link is coupled to the load and couplable to a power source. The load comprises an AC electrical component. The inverter is configured to provide an output voltage and an output current to the AC electrical component, the output voltage having an output frequency. The controller is configured to: evaluate a component startup criterion relating to whether the AC electrical component is performing a startup process; in response to a determination that the component startup criterion has been met, operate the inverter in a protected startup mode; and when operating the inverter in the protected startup mode, control the output frequency such that the output frequency increases with time until the output frequency reaches a predefined operating frequency.

First claim

The invention claimed is:

1 . An apparatus comprising:
a controller, an inverter, a load and a DC link, wherein: the DC link is:
coupled to the inverter, and
couplable to a power source;
the load comprises an AC electrical component; the inverter is configured to provide an output voltage and an output current to the AC electrical component, the output voltage having an output frequency; the controller is configured to:
evaluate a component startup criterion relating to whether the AC electrical component is performing a startup process,
in response to a determination that the component startup criterion has been met, operate the inverter in a protected startup mode, and
when operating the inverter in the protected startup mode, control the output frequency such that the output frequency increases with time until the output frequency reaches a predefined operating frequency,
wherein, when operating the inverter in the protected startup mode, the controller is operative to:
record a time elapsed since the component startup criterion was determined to have been met; and
control the output frequency according to a predetermined startup scheme which defines a relationship between:
the output voltage and the recorded time elapsed, and
the output frequency and the recorded time elapsed.

2 . The apparatus of claim 1 , wherein
the controller is configured to:
in response to a determination that the component startup criterion has not been met, operate the inverter in a non-startup mode; and
when operating the inverter in the non-startup mode, control the output frequency such that the output frequency is equal to a non-startup frequency, wherein the non-startup frequency is equal to the predefined operating frequency.

3 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output voltage such that the output voltage increases with time until the output frequency reaches the predefined operating frequency.

4 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output voltage based on the output frequency.

5 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
control the output frequency based on the monitored output current.

6 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
control the output frequency to maintain the monitored output current at or below an upper output current threshold.

7 . The apparatus of claim 6 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output frequency to maintain the monitored output current at or below the upper output current threshold and within a target output current range of the upper output current threshold.

8 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
calculate an output power based on the output voltage and the monitored output current; and
control the output frequency to maintain the calculated output power at or below an upper output power threshold.

9 . The apparatus of claim 8 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output frequency to maintain the calculated output power at or below the upper output power threshold and within a target output power range of the upper output power threshold.

10 . The apparatus of claim 2 ,
wherein the relationship between:
the output voltage and the recorded time elapsed defined by the predetermined startup scheme is such that the output voltage increases as the time elapsed increases; and
the output frequency and the recorded time elapsed defined by the predetermined startup scheme is such that the output frequency increases as the time elapsed increases.

11 . The apparatus of claim 1 , wherein
the controller is configured to:
monitor the output current of the inverter;
compare the monitored output current to a startup output current threshold; and
determine that the component startup criterion has been met if the monitored output current exceeds the startup output current threshold.

12 . The apparatus of claim 1 , wherein
the controller is configured to:
monitor the output current of the inverter;
calculate a rate of change of the monitored output current;
compare the calculated rate of change of the monitored output current to a startup output current rate of change threshold; and
determine that the component startup criterion has been met if the calculated rate of change of the monitored output current exceeds the startup output current rate of change threshold.

13 . The apparatus of claim 1 , wherein
the controller is configured to:
receive a startup signal; and
determine whether the component startup criterion has been met based on the startup signal.

14 . A transport refrigeration system comprising the apparatus of claim 1 , wherein the AC electrical component is configured to drive a compressor of the transport refrigeration system.

15 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
control the output frequency and the output voltage, based on the monitored output current.

16 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
control the output frequency and the output voltage to maintain the monitored output current at or below an upper output current threshold.

17 . The apparatus of claim 16 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output frequency and the output voltage to maintain the monitored output current at or below the upper output current threshold and within a target output current range of the upper output current threshold.

18 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
monitor the output current of the inverter;
calculate an output power based on the output voltage and the monitored output current; and
control the output frequency and the output voltage to maintain the calculated output power at or below an upper output power threshold.

19 . The apparatus of claim 18 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
control the output frequency and the output voltage to maintain the calculated output power at or below the upper output power threshold and within a target output power range of the upper output power threshold.

20 . The apparatus of claim 1 , wherein
when operating the inverter in the protected startup mode, the controller is operative to:
record a time elapsed since the component startup criterion was determined to have been met; and
control the output frequency and the output voltage according to a predetermined sta

Assignees

• Thermo King Llc

Inventors

• Gorski Matthias

Classifications

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J3/36

  Arrangements for transfer of electric power between AC networks via high-voltage DC [HVDC] links; Arrangements for transfer of electric power between generators and networks via HVDC links · CPC title

• B60L2210/42

  Voltage source inverters · CPC title

• H02J3/322

  the battery being on-board an electric or hybrid vehicle, e.g. vehicle to grid arrangements [V2G], power aggregation, use of the battery for network load balancing, coordinated or cooperative battery charging · CPC title

• H02P1/30

  by progressive increase of frequency of supply to primary circuit of motor · CPC title