Pump control device

Patent metadata

Field	Value
Publication number	US-2018262148-A1
Application number	US-201815915636-A
Country	US
Kind code	A1
Filing date	Mar 8, 2018
Priority date	Mar 9, 2017
Publication date	Sep 13, 2018
Grant date	—

Abstract

A pump control device includes: a current detection unit detecting a current value of current flowing through a coil of a motor driving an electric pump; a determination unit determining whether a determination condition in which the detected current value is equal to or larger than a preset value and the current value equal to or larger than the preset value continues for a preset time or more is satisfied; an inverter including three arm units having high-side and low-side switching elements connected to each other in series between first and second power supply lines; and an energization control unit driving the high-side and low-side switching elements by PWM control, and perform the PWM control by lowering a carrier frequency of a PWM signal by a predetermined frequency when the determination condition is satisfied.

First claim

What is claimed is:

1 . A pump control device comprising:
a current detection unit configured to detect a current value of current flowing through a coil of a motor, which drives an electric pump; a determination unit configured to determine whether or not a determination condition in which the detected current value is equal to or larger than a preset value and the current value equal to or larger than the preset value continues for a preset time or more is satisfied; an inverter including three sets of arm units each having a high-side switching element and a low-side switching element, which are connected to each other in series between a first power supply line and a second power supply line, which is connected to a potential lower than a potential of the first power supply line, the inverter controlling the current flowing through the coil; and an energization control unit configured to drive the high-side switching element and the low-side switching element by PWM control, and perform the PWM control by lowering a carrier frequency of a PWM signal used for the PWM control from a current frequency by a predetermined frequency when it is determined by the determination unit that the determination condition is satisfied.

2 . The pump control device according to claim 1 ,
wherein the energization control unit lowers the carrier frequency according to a difference between the current value detected by the current detection unit and the preset value.

3 . The pump control device according to claim 1 , further comprising:
a temperature information acquisition unit configured to acquire temperature information indicating a temperature of a board on which a component, which is an overheating protection target, is mounted; a calculation unit configured to calculate a cumulative value of a product of the temperature and a time during which the corresponding temperature is maintained; and a processing unit configured to perform a preset processing when the cumulative value exceeds a preset threshold.

4 . The pump control device according to claim 3 ,
wherein the preset threshold is a first threshold, and the energization control unit stops the PWM control when the cumulative value exceeds a second threshold smaller than the first threshold, and resumes the PWM control when the temperature falls below a preset temperature threshold during stop of the PWM control.

Assignees

• Aisin Seiki

Inventors

• Endo Kazutaka

Classifications

• F04B2203/0204

  Frequency of the electric current · CPC title

• F04B49/065

  and making use of computers · CPC title

• F04B49/06

  Control using electricity (regulating by means of floats actuating electric switches F04B49/04) · CPC title

• H02P27/085 Primary

  wherein the PWM mode is adapted on the running conditions of the motor, e.g. the switching frequency · CPC title

• H02P27/08 Primary

  with pulse width modulation · CPC title