Title:
VOLTAGE LIMITING CIRCUIT
Document Type and Number:
WIPO Patent Application WO/2021/031766
Kind Code:
A1
Abstract:
A voltage limiting circuit, comprising: a voltage-control-type switch (6), a resistor (7), a positive temperature coefficient thermistor (5) and a varistor (4), wherein the voltage-control-type switch (6) and the resistor (7) are connected in series and are then connected to the positive temperature coefficient thermistor (5) in parallel to form a series-parallel branch; one end of the series-parallel branch is an input electrode terminal (1) of the voltage limiting circuit, and the other end thereof is an output electrode terminal (2) of the voltage limiting circuit; the other end of the series-parallel branch is also connected to the varistor (4) in series; one end of the varistor (4) is connected to the series-parallel branch, and the other end thereof is a common electrode terminal (3) of the voltage limiting circuit; and the positive temperature coefficient thermistor (5) is thermally coupled to the varistor (4). The power output capability of the voltage limiting circuit is improved by means of the dynamic conduction of a voltage dividing circuit of the resistor (7), thereby making it possible to adapt to the power requirements of an electric energy meter in different operating states; and a voltage output to a switching power source of the electric energy meter can be stabilized between 110 and 330 V during power switching (during a jumping process), thereby guaranteeing the normal operation of the switching power source of the electric energy meter.
Inventors:
SHI XIAOLONG (CN)
ZHANG ZHICHENG (CN)
ZHANG JUN (CN)
LI KE (CN)
ZHANG XU (CN)
ZHANG ZHICHENG (CN)
ZHANG JUN (CN)
LI KE (CN)
ZHANG XU (CN)
Application Number:
PCT/CN2020/103038
Publication Date:
February 25, 2021
Filing Date:
July 20, 2020
Export Citation:
Assignee:
CHENGDU TIEDA ELECTRONIC CO LTD (CN)
International Classes:
H02H9/04
Foreign References:
| CN110336264A | 2019-10-15 | |||
| CN201111299Y | 2008-09-03 | |||
| CN108808648A | 2018-11-13 | |||
| CN103311914A | 2013-09-18 | |||
| CN103346547A | 2013-10-09 | |||
| US5781394A | 1998-07-14 |
Attorney, Agent or Firm:
SICHUAN LIJIU LAW FIRM (CN)
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