Apparatus and method for on-line resistance measurement
A technology for measuring resistance and measuring circuit, which is applied in the field of online measurement of resistance value, can solve the problems of large measurement error, high price, unfavorable promotion and use, etc., and achieve the effect of small measurement error and simple implementation
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Publication Date
- 2011-01-12
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
Figure 1 Figure 2 Figure 3
Abstract
Description
technical field
[0001] The invention relates to an on-line measurement technology of resistance resistance, in particular to a device and method for quickly and accurately on-line measurement of resistance resistance using a phase method under the condition that resistance and inductance are connected in parallel (RL circuit). Background technique
[0002] In the process of online measurement of resistance value by phase method, the accuracy of phase angle (phase difference) is the key point of the whole measurement process. At present, there are two commonly used methods for measuring the phase angle:
[0003] One is the phase measurement method using the filling counting method. Generally, the zero-crossing phase detection method is used to obtain the phase value between two signals of the same frequency; the principle of the zero-crossing phase detection method is as follows: two measured signals of the same frequency are shaped into two square wave signals, and the lead...
Examples
Embodiment Construction
[0028] Please refer to figure 1 As shown, the measuring device in this embodiment includes: a measuring circuit 110 and a resistance calculation unit 120 . Wherein, the measurement circuit 110 includes: a power supply of AC constant voltage, whose effective voltage value is U; a variable reference resistor R connected in series x and inductance L. And the resistance R to be measured is connected in parallel with the inductance L. Moreover, the reference resistor is suitable for measuring various resistance values, which at least include 1 ohm, 10 ohm, 100 ohm, 1K ohm, 10K ohm, 100K ohm and 1M ohm to be selected.
[0029] For ease of understanding, how the present invention converts the directly measured phase difference into an indirectly measured phase difference will be further described in detail below.
[0030] In the measurement circuit 110 , the resistance R to be measured and the inductance L are connected in parallel to form an RL circuit. In the RL circuit, in ord...